Merge remote-tracking branch 'origin/dev' into web-server-offline-hint

tests/component_tests/esp32_ble_server/config/improv_only.yaml

@@ -0,0 +1,13 @@
+esphome:
+  name: test
+
+esp32:
+  variant: esp32
+
+wifi:
+  ssid: MySSID
+  password: password1
+
+# esp32_ble_server is only auto-loaded here, so it has no services of its own.
+esp32_improv:
+  authorizer: none

tests/component_tests/esp32_ble_server/config/manufacturer_data_only.yaml

@@ -0,0 +1,9 @@
+esphome:
+  name: test
+
+esp32:
+  variant: esp32
+
+esp32_ble_server:
+  id: ble_server
+  manufacturer_data: [0x72, 0x04, 0x00, 0x23]

tests/component_tests/esp32_ble_server/config/own_service.yaml

@@ -0,0 +1,14 @@
+esphome:
+  name: test
+
+esp32:
+  variant: esp32
+
+esp32_ble_server:
+  id: ble_server
+  services:
+    - uuid: 2a24b789-7aab-4535-af3e-ee76a35cc12d
+      characteristics:
+        - uuid: cad48e28-7fbe-41cf-bae9-d77a6c233423
+          read: true
+          value: [1, 2, 3, 4]

tests/component_tests/esp32_ble_server/test_esp32_ble_server.py

@@ -1,5 +1,10 @@
 """Tests for esp32_ble_server configuration helpers."""
 
+from __future__ import annotations
+
+from collections.abc import Callable
+from pathlib import Path
+
 import pytest
 
 from esphome.components.esp32_ble_server import (
@@ -45,3 +50,26 @@ def test_uuid_is_matches_descriptor_short_strings(uuid16) -> None:
     assert uuid_is(uuid16, uuid16)
     assert uuid_is(f"{uuid16:04X}", uuid16)
     assert uuid_is(f"{uuid16:08X}", uuid16)
+
+
+@pytest.mark.parametrize(
+    ("config_file", "required"),
+    [
+        # Auto-loaded by esp32_improv only: nothing to find until Improv asks for it
+        ("improv_only.yaml", False),
+        # The configuration defines a service clients are meant to connect to
+        ("own_service.yaml", True),
+        # Manufacturer data is only useful if it is actually broadcast
+        ("manufacturer_data_only.yaml", True),
+    ],
+)
+def test_advertising_required(
+    generate_main: Callable[[str | Path], str],
+    component_config_path: Callable[[str], Path],
+    config_file: str,
+    required: bool,
+) -> None:
+    """The server only requests advertising when the configuration needs it."""
+    main_cpp = generate_main(component_config_path(config_file))
+
+    assert f"set_advertising_required({str(required).lower()})" in main_cpp

tests/component_tests/lvgl/config/keyboard_no_label.yaml

@@ -0,0 +1,32 @@
+esphome:
+  name: test-keyboard-no-label
+
+esp32:
+  board: esp32dev
+  framework:
+    type: esp-idf
+
+spi:
+  - id: spi_bus
+    clk_pin: GPIO18
+    mosi_pin: GPIO23
+
+display:
+  - platform: mipi_spi
+    spi_id: spi_bus
+    model: st7789v
+    id: tft_display
+    dimensions:
+      width: 240
+      height: 320
+    cs_pin: GPIO22
+    dc_pin: GPIO21
+    auto_clear_enabled: false
+    invert_colors: false
+    update_interval: never
+
+lvgl:
+  displays: tft_display
+  widgets:
+    - keyboard:
+        id: keyboard_widget

tests/component_tests/lvgl/config/qrcode_no_label.yaml

@@ -0,0 +1,34 @@
+esphome:
+  name: test-qrcode-no-label
+
+esp32:
+  board: esp32dev
+  framework:
+    type: esp-idf
+
+spi:
+  - id: spi_bus
+    clk_pin: GPIO18
+    mosi_pin: GPIO23
+
+display:
+  - platform: mipi_spi
+    spi_id: spi_bus
+    model: st7789v
+    id: tft_display
+    dimensions:
+      width: 240
+      height: 320
+    cs_pin: GPIO22
+    dc_pin: GPIO21
+    auto_clear_enabled: false
+    invert_colors: false
+    update_interval: never
+
+lvgl:
+  displays: tft_display
+  widgets:
+    - qrcode:
+        id: qr_widget
+        size: 100
+        text: "esphome.io"

tests/component_tests/lvgl/config/tabview_no_label.yaml

@@ -0,0 +1,35 @@
+esphome:
+  name: test-tabview-no-label
+
+esp32:
+  board: esp32dev
+  framework:
+    type: esp-idf
+
+spi:
+  - id: spi_bus
+    clk_pin: GPIO18
+    mosi_pin: GPIO23
+
+display:
+  - platform: mipi_spi
+    spi_id: spi_bus
+    model: st7789v
+    id: tft_display
+    dimensions:
+      width: 240
+      height: 320
+    cs_pin: GPIO22
+    dc_pin: GPIO21
+    auto_clear_enabled: false
+    invert_colors: false
+    update_interval: never
+
+lvgl:
+  displays: tft_display
+  widgets:
+    - tabview:
+        id: tabview_widget
+        tabs:
+          - name: "Tab 1"
+            id: tab_1

tests/component_tests/lvgl/test_widget_label_dependency.py

@@ -0,0 +1,32 @@
+"""Widgets whose LVGL C implementation creates or references labels
+internally (tab titles, key legends, the QR canvas fallback) must declare
+the label dependency in ``get_uses()``. Otherwise a config that contains
+no ``label`` widget of its own compiles LVGL without ``LV_USE_LABEL`` and
+fails at C compile time with undefined ``lv_label_*`` symbols.
+"""
+
+from __future__ import annotations
+
+from collections.abc import Callable
+from pathlib import Path
+
+import pytest
+
+from esphome.components.lvgl import defines as df
+
+
+@pytest.mark.parametrize(
+    "yaml_file",
+    [
+        "qrcode_no_label.yaml",
+        "keyboard_no_label.yaml",
+        "tabview_no_label.yaml",
+    ],
+)
+def test_label_less_config_enables_lv_use_label(
+    generate_main: Callable[[str | Path], str],
+    component_config_path: Callable[[str], Path],
+    yaml_file: str,
+) -> None:
+    generate_main(component_config_path(yaml_file))
+    assert "LV_USE_LABEL" in df.get_defines()

tests/component_tests/noise/test_encryption_key.py

@@ -5,11 +5,7 @@ from __future__ import annotations
 import pytest
 
 from esphome import config_validation as cv
-from esphome.components.noise import (
-    decode_encryption_key,
-    is_reserved_key,
-    validate_encryption_key,
-)
+from esphome.components.noise import decode_encryption_key, validate_encryption_key
 
 KEY = "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8="
 
@@ -41,6 +37,8 @@ def test_decode_encryption_key_rejects_short_decode() -> None:
         decode_encryption_key("AAECAw==")
 
 
-def test_is_reserved_key() -> None:
-    assert is_reserved_key("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=")
-    assert not is_reserved_key(KEY)
+def test_validate_encryption_key_rejects_all_zeros() -> None:
+    """The all-zeros key is the provisioning sentinel the device treats as no
+    key, so it never reaches a build."""
+    with pytest.raises(cv.Invalid, match="all-zeros key is reserved"):
+        validate_encryption_key("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=")

tests/component_tests/ota/test_esphome_ota.py

@@ -2,6 +2,7 @@
 
 from __future__ import annotations
 
+from collections.abc import Callable
 import logging
 from typing import Any
 
@@ -14,6 +15,7 @@ from esphome.components.esphome.ota import (
     _validate_no_password_with_encryption,
     ota_esphome_final_validate,
 )
+from esphome.components.noise import static_encryption_key
 from esphome.const import (
     CONF_API,
     CONF_ENCRYPTION,
@@ -115,7 +117,6 @@ def test_non_esphome_ota_unaffected() -> None:
 
 API_KEY = "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8="
 OTHER_KEY = "AQIDBAUGBwgJCgsMDQ4PEBESExQVFhcYGRobHB0eHyA="
-ZEROS_KEY = "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA="
 
 
 def test_encryption_key_inherited_from_api() -> None:
@@ -197,36 +198,6 @@ def test_encryption_without_any_key_rejected() -> None:
         fv.full_config.reset(token)
 
 
-def test_encryption_explicit_all_zeros_key_rejected() -> None:
-    """The all-zeros key is the provisioning sentinel; the device would treat
-    it as no PSK and accept plaintext, so it must fail validation."""
-    full_conf = {
-        CONF_OTA: [
-            _make_ota_config(port=3232, **{CONF_ENCRYPTION: {CONF_KEY: ZEROS_KEY}})
-        ],
-    }
-    token = fv.full_config.set(full_conf)
-    try:
-        with pytest.raises(cv.Invalid, match="all-zeros key is reserved"):
-            ota_esphome_final_validate({})
-    finally:
-        fv.full_config.reset(token)
-
-
-def test_encryption_inherited_all_zeros_key_rejected() -> None:
-    """An all-zeros api key must not silently disable ota encryption either."""
-    full_conf = {
-        CONF_API: {CONF_ENCRYPTION: {CONF_KEY: ZEROS_KEY}},
-        CONF_OTA: [_make_ota_config(port=3232, **{CONF_ENCRYPTION: {}})],
-    }
-    token = fv.full_config.set(full_conf)
-    try:
-        with pytest.raises(cv.Invalid, match="all-zeros key is reserved"):
-            ota_esphome_final_validate({})
-    finally:
-        fv.full_config.reset(token)
-
-
 def test_encryption_key_mismatch_between_merged_configs_rejected() -> None:
     """Same-port configs with different encryption keys raise."""
     full_conf = {
@@ -295,13 +266,14 @@ def test_encryption_explicit_key_with_runtime_provisioned_api_accepted() -> None
         fv.full_config.reset(token)
 
 
+@pytest.mark.parametrize("component", ["web_server", "prometheus"])
 def test_encryption_with_web_server_ota_warns(
-    caplog: pytest.LogCaptureFixture,
+    caplog: pytest.LogCaptureFixture, component: str
 ) -> None:
-    """With the web_server component the plaintext /update endpoint is always
-    on; the combination validates with a warning."""
+    """web_server and prometheus keep the shared listener up, so the
+    plaintext /update endpoint is always on and the combination warns."""
     full_conf = {
-        "web_server": {},
+        component: {},
         CONF_OTA: [
             _make_ota_config(port=3232, **{CONF_ENCRYPTION: {CONF_KEY: OTHER_KEY}}),
             {CONF_PLATFORM: "web_server", CONF_ID: ID("ota_ws", is_manual=False)},
@@ -316,12 +288,12 @@ def test_encryption_with_web_server_ota_warns(
         fv.full_config.reset(token)
 
 
-def test_encryption_with_captive_portal_web_server_ota_warns(
+def test_encryption_with_captive_portal_does_not_warn(
     caplog: pytest.LogCaptureFixture,
 ) -> None:
     """captive_portal auto-loads the web_server ota platform without the
-    web_server component; encryption stays usable and only warns, so the
-    fallback AP recovery path is not lost."""
+    web_server component; its endpoint only exists while the fallback AP is
+    active and is the intended recovery path, so there is no warning."""
     full_conf = {
         "captive_portal": {},
         CONF_OTA: [
@@ -333,7 +305,10 @@ def test_encryption_with_captive_portal_web_server_ota_warns(
     try:
         with caplog.at_level(logging.WARNING):
             ota_esphome_final_validate({})
-        assert any("captive_portal" in record.message for record in caplog.records)
+        assert not any(
+            "OTA encryption does not cover" in record.message
+            for record in caplog.records
+        )
         esphome_conf = next(
             conf
             for conf in fv.full_config.get()[CONF_OTA]
@@ -344,6 +319,100 @@ def test_encryption_with_captive_portal_web_server_ota_warns(
         fv.full_config.reset(token)
 
 
+def test_password_with_api_key_warns(caplog: pytest.LogCaptureFixture) -> None:
+    """A static api key makes the device offer encryption and the CLI take
+    it, so the password is dead weight; the config validates with a warning."""
+    full_conf = {
+        CONF_API: {CONF_ENCRYPTION: {CONF_KEY: API_KEY}},
+        CONF_OTA: [_make_ota_config(port=3232, **{CONF_PASSWORD: "pw"})],
+    }
+    token = fv.full_config.set(full_conf)
+    try:
+        with caplog.at_level(logging.WARNING):
+            ota_esphome_final_validate({})
+        assert any("wastes significant flash" in r.message for r in caplog.records)
+    finally:
+        fv.full_config.reset(token)
+
+
+def test_password_with_runtime_api_key_warns_differently(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """The CLI still needs the password, but the provisioned key also
+    authenticates uploads; the warning says so without the flash advice."""
+    full_conf = {
+        CONF_API: {CONF_ENCRYPTION: {}},
+        CONF_OTA: [_make_ota_config(port=3232, **{CONF_PASSWORD: "pw"})],
+    }
+    token = fv.full_config.set(full_conf)
+    try:
+        with caplog.at_level(logging.WARNING):
+            ota_esphome_final_validate({})
+        messages = [r.message for r in caplog.records]
+        assert any("provisioned at runtime also authenticates" in m for m in messages)
+        assert not any("wastes significant flash" in m for m in messages)
+    finally:
+        fv.full_config.reset(token)
+
+
+def test_password_without_api_key_no_warning(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """Without an api key there is no offer, so nothing to warn about."""
+    full_conf = {
+        CONF_API: {},
+        CONF_OTA: [_make_ota_config(port=3232, **{CONF_PASSWORD: "pw"})],
+    }
+    token = fv.full_config.set(full_conf)
+    try:
+        with caplog.at_level(logging.WARNING):
+            ota_esphome_final_validate({})
+        assert not any("authenticates" in r.message for r in caplog.records)
+    finally:
+        fv.full_config.reset(token)
+
+
+def test_web_server_component_without_ota_platform_does_not_warn(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """The web_server component alone has no /update endpoint."""
+    full_conf = {
+        "web_server": {},
+        CONF_OTA: [
+            _make_ota_config(port=3232, **{CONF_ENCRYPTION: {CONF_KEY: OTHER_KEY}})
+        ],
+    }
+    token = fv.full_config.set(full_conf)
+    try:
+        with caplog.at_level(logging.WARNING):
+            ota_esphome_final_validate({})
+        assert not any(
+            "OTA encryption does not cover" in r.message for r in caplog.records
+        )
+    finally:
+        fv.full_config.reset(token)
+
+
+def test_web_server_ota_platform_alone_does_not_warn(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """Only the web_server component starts the shared listener, so the ota
+    platform on its own never exposes /update."""
+    full_conf = {
+        CONF_OTA: [
+            _make_ota_config(port=3232, **{CONF_ENCRYPTION: {CONF_KEY: OTHER_KEY}}),
+            {CONF_PLATFORM: "web_server", CONF_ID: ID("ota_ws", is_manual=False)},
+        ],
+    }
+    token = fv.full_config.set(full_conf)
+    try:
+        with caplog.at_level(logging.WARNING):
+            ota_esphome_final_validate({})
+        assert not any("plaintext /update" in r.message for r in caplog.records)
+    finally:
+        fv.full_config.reset(token)
+
+
 def test_web_server_ota_without_encryption_unaffected() -> None:
     """web_server ota stays valid alongside an unencrypted esphome entry."""
     full_conf = {
@@ -370,20 +439,87 @@ def test_auto_load_pulls_noise_only_for_encryption() -> None:
     assert "noise" in AUTO_LOAD({})
 
 
-def test_filter_source_files_excludes_noise_without_encryption() -> None:
-    """The noise transport source compiles only for encrypted builds."""
-    old_config = CORE.config
-    try:
-        CORE.config = {CONF_OTA: [_make_ota_config(port=3232)]}
-        assert FILTER_SOURCE_FILES() == ["ota_esphome_noise.cpp"]
-        CORE.config = {
-            CONF_OTA: [
-                _make_ota_config(port=3232, **{CONF_ENCRYPTION: {CONF_KEY: API_KEY}})
-            ]
-        }
-        assert FILTER_SOURCE_FILES() == []
-    finally:
-        CORE.config = old_config
+def test_static_encryption_key() -> None:
+    """Only a build-time key counts; a runtime provisioned one does not."""
+    assert static_encryption_key({}) is None
+    assert static_encryption_key({CONF_ENCRYPTION: {}}) is None
+    assert static_encryption_key({CONF_ENCRYPTION: {CONF_KEY: API_KEY}}) == API_KEY
+
+
+@pytest.mark.parametrize(
+    ("yaml_name", "defines_present", "defines_absent"),
+    [
+        # An api key alone compiles the transport in without requiring it;
+        # the device uses the api server's key, not a copy
+        (
+            "api_key_offer",
+            {"USE_OTA_ENCRYPTION", "USE_OTA_ENCRYPTION_FROM_API"},
+            {"USE_OTA_ENCRYPTION_REQUIRED", "USE_OTA_ENCRYPTION_PROVISIONED"},
+        ),
+        # A password still guards plaintext uploads on an offering device
+        (
+            "api_key_offer_password",
+            {"USE_OTA_ENCRYPTION", "USE_OTA_ENCRYPTION_FROM_API", "USE_OTA_PASSWORD"},
+            {"USE_OTA_ENCRYPTION_REQUIRED", "USE_OTA_ENCRYPTION_PROVISIONED"},
+        ),
+        # The ota encryption block is what makes the device refuse plaintext
+        (
+            "encryption_required",
+            {
+                "USE_OTA_ENCRYPTION",
+                "USE_OTA_ENCRYPTION_REQUIRED",
+                "USE_OTA_ENCRYPTION_FROM_API",
+            },
+            {"USE_OTA_ENCRYPTION_PROVISIONED"},
+        ),
+        # Without api encryption the ota key is the device's own
+        (
+            "own_key",
+            {"USE_OTA_ENCRYPTION", "USE_OTA_ENCRYPTION_REQUIRED"},
+            {"USE_OTA_ENCRYPTION_FROM_API", "USE_OTA_ENCRYPTION_PROVISIONED"},
+        ),
+        # A key provisioned at runtime lives in the api server; the device
+        # offers with it once provisioned and never requires it
+        (
+            "runtime_api_key",
+            {
+                "USE_OTA_ENCRYPTION",
+                "USE_OTA_ENCRYPTION_FROM_API",
+                "USE_OTA_ENCRYPTION_PROVISIONED",
+            },
+            {"USE_OTA_ENCRYPTION_REQUIRED"},
+        ),
+        # No api encryption at all keeps the noise glue out of the build
+        (
+            "plain",
+            set(),
+            {
+                "USE_OTA_ENCRYPTION",
+                "USE_OTA_ENCRYPTION_REQUIRED",
+                "USE_OTA_ENCRYPTION_FROM_API",
+                "USE_OTA_ENCRYPTION_PROVISIONED",
+            },
+        ),
+    ],
+)
+def test_encryption_offer_codegen(
+    generate_main: Callable[[str], str],
+    yaml_name: str,
+    defines_present: set[str],
+    defines_absent: set[str],
+) -> None:
+    main_cpp = generate_main(
+        f"tests/component_tests/ota/test_esphome_ota_{yaml_name}.yaml"
+    )
+    defines = {define.name for define in CORE.defines}
+    assert defines_present <= defines
+    assert not (defines_absent & defines)
+    encrypted = "USE_OTA_ENCRYPTION" in defines_present
+    own_key = encrypted and "USE_OTA_ENCRYPTION_FROM_API" not in defines_present
+    assert ("esphome_esphomeotacomponent_id->set_noise_psk(" in main_cpp) is own_key
+    assert ("set_auth_password(" in main_cpp) is ("USE_OTA_PASSWORD" in defines_present)
+    # The noise transport source compiles only when the define is set
+    assert FILTER_SOURCE_FILES() == ([] if encrypted else ["ota_esphome_noise.cpp"])
 
 
 def test_password_with_encryption_rejected() -> None:

tests/component_tests/ota/test_esphome_ota_api_key_offer.yaml

@@ -0,0 +1,11 @@
+esphome:
+  name: ota-offer
+
+host:
+
+api:
+  encryption:
+    key: "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8="
+
+ota:
+  - platform: esphome

tests/component_tests/ota/test_esphome_ota_api_key_offer_password.yaml

@@ -0,0 +1,12 @@
+esphome:
+  name: ota-offer-password
+
+host:
+
+api:
+  encryption:
+    key: "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8="
+
+ota:
+  - platform: esphome
+    password: "superlongpasswordthatnoonewillknow"

tests/component_tests/ota/test_esphome_ota_encryption_required.yaml

@@ -0,0 +1,12 @@
+esphome:
+  name: ota-encryption-required
+
+host:
+
+api:
+  encryption:
+    key: "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8="
+
+ota:
+  - platform: esphome
+    encryption:

tests/component_tests/ota/test_esphome_ota_own_key.yaml

@@ -0,0 +1,11 @@
+esphome:
+  name: ota-own-key
+
+host:
+
+api:
+
+ota:
+  - platform: esphome
+    encryption:
+      key: "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8="

tests/component_tests/ota/test_esphome_ota_plain.yaml

@@ -0,0 +1,9 @@
+esphome:
+  name: ota-plain
+
+host:
+
+api:
+
+ota:
+  - platform: esphome

tests/component_tests/ota/test_esphome_ota_runtime_api_key.yaml

@@ -0,0 +1,10 @@
+esphome:
+  name: ota-runtime-key
+
+host:
+
+api:
+  encryption:
+
+ota:
+  - platform: esphome

tests/component_tests/remote_transmitter/test_non_blocking_gate.py

@@ -26,7 +26,7 @@ from ..types import SetCoreConfigCallable
         (PlatformFramework.ESP32_IDF, None, True),
         (PlatformFramework.RTL87XX_ARDUINO, FAMILY_RTL8720C, True),
         (PlatformFramework.RTL87XX_ARDUINO, FAMILY_RTL8710B, False),
-        (PlatformFramework.BK72XX_ARDUINO, FAMILY_BK7231N, True),
+        (PlatformFramework.BK72XX_ARDUINO, FAMILY_BK7231N, False),
         (PlatformFramework.BK72XX_ARDUINO, FAMILY_BK7238, True),
         (PlatformFramework.BK72XX_ARDUINO, FAMILY_BK7231T, False),
         (PlatformFramework.ESP8266_ARDUINO, None, False),

tests/component_tests/sdl/test_sdl.py

@@ -0,0 +1,101 @@
+"""Tests for the sdl display schema, in particular the headless option."""
+
+from __future__ import annotations
+
+import pytest
+
+from esphome import config_validation as cv
+from esphome.components.sdl.display import (
+    CONF_SDL_ID,
+    CONFIG_SCHEMA,
+    headless_final_validate,
+)
+from esphome.config import Config
+from esphome.const import PlatformFramework
+from esphome.core import ID
+from esphome.final_validate import full_config
+from esphome.types import ConfigType
+from tests.component_tests.types import SetCoreConfigCallable
+
+
+@pytest.fixture(autouse=True)
+def _host_platform(set_core_config: SetCoreConfigCallable) -> None:
+    set_core_config(PlatformFramework.HOST_NATIVE)
+
+
+def _config(**extra: object) -> ConfigType:
+    config: ConfigType = {
+        "dimensions": {"width": 320, "height": 240},
+        # sdl2-config is not necessarily installed in the test environment
+        "sdl_options": "-lSDL2",
+    }
+    config.update(extra)
+    return config
+
+
+def test_defaults_to_windowed() -> None:
+    """A display without the option is not headless."""
+    assert CONFIG_SCHEMA(_config())["headless"] is False
+
+
+def test_headless_accepted() -> None:
+    """A headless display needs nothing beyond the dimensions."""
+    assert CONFIG_SCHEMA(_config(headless=True))["headless"] is True
+
+
+def test_headless_rejects_window_options() -> None:
+    """Window options are meaningless without a window."""
+    with pytest.raises(cv.Invalid, match="has no effect"):
+        CONFIG_SCHEMA(
+            _config(headless=True, window_options={"position": {"x": 0, "y": 0}})
+        )
+
+
+def test_headless_rejects_snapshot_key() -> None:
+    """A headless display has no keyboard, so the action is the only way in."""
+    with pytest.raises(cv.Invalid, match="snapshot.take"):
+        CONFIG_SCHEMA(_config(headless=True, snapshot_key="SDLK_F12"))
+
+
+def test_snapshot_key_accepted_when_windowed() -> None:
+    """The key is only valid alongside a window."""
+    config = CONFIG_SCHEMA(_config(snapshot_key="SDLK_F12"))
+    assert str(config["snapshot_key"]) == "SDLK_F12"
+
+
+def _declare_sdl_display(headless: bool) -> ID:
+    """Register a full_config with a single sdl display declaration and return a reference to it.
+
+    Mirrors what the real config pipeline leaves behind: a "display" domain entry plus a
+    declare_ids record id_declaration_match_schema uses to find it again.
+    """
+    declared_id = ID("my_sdl", is_declaration=True)
+    fc = Config()
+    fc["display"] = [
+        {
+            "platform": "sdl",
+            "id": declared_id,
+            "headless": headless,
+            "dimensions": {"width": 320, "height": 240},
+        }
+    ]
+    fc.declare_ids.append((declared_id, ["display", 0, "id"]))
+    full_config.set(fc)
+    return ID("my_sdl")
+
+
+@pytest.mark.parametrize("platform", ["binary_sensor", "touchscreen"])
+def test_headless_final_validate_rejects_headless_display(platform: str) -> None:
+    """binary_sensor and touchscreen both need a window, so a headless display is rejected."""
+    sdl_ref = _declare_sdl_display(headless=True)
+    schema = headless_final_validate(platform)
+    with pytest.raises(cv.Invalid, match="needs a window"):
+        schema({CONF_SDL_ID: sdl_ref})
+
+
+@pytest.mark.parametrize("platform", ["binary_sensor", "touchscreen"])
+def test_headless_final_validate_accepts_windowed_display(platform: str) -> None:
+    """The same platforms are accepted once the display has a window."""
+    sdl_ref = _declare_sdl_display(headless=False)
+    schema = headless_final_validate(platform)
+    schema({CONF_SDL_ID: sdl_ref})  # Should not raise.

tests/component_tests/template/test_template_climate.py

@@ -0,0 +1,145 @@
+"""Tests for template climate config validation."""
+
+import pytest
+
+from esphome import config_validation as cv
+from esphome.components.template.climate import (
+    CONF_SET_TARGET_HUMIDITY_ACTION,
+    CONF_SET_TARGET_TEMPERATURE_ACTION,
+    CONF_SET_TARGET_TEMPERATURE_HIGH_ACTION,
+    CONF_SET_TARGET_TEMPERATURE_LOW_ACTION,
+    CONF_SUPPORTS_CURRENT_HUMIDITY,
+    CONF_SUPPORTS_CURRENT_TEMPERATURE,
+    CONF_SUPPORTS_TARGET_HUMIDITY,
+    CONF_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE,
+    CONF_TARGET_HUMIDITY,
+    _resolve_supports,
+    _validate_initial_state,
+    _validate_set_actions,
+)
+from esphome.const import (
+    CONF_HUMIDITY_SENSOR,
+    CONF_INITIAL_STATE,
+    CONF_SENSOR,
+    CONF_TARGET_TEMPERATURE,
+    CONF_TARGET_TEMPERATURE_HIGH,
+    CONF_TARGET_TEMPERATURE_LOW,
+)
+from esphome.types import ConfigType
+
+
+def test_supports_current_temperature_derived_from_sensor() -> None:
+    config: ConfigType = {CONF_SENSOR: "some_sensor"}
+    assert _resolve_supports(config)[CONF_SUPPORTS_CURRENT_TEMPERATURE] is True
+
+
+def test_supports_current_temperature_false_without_sensor() -> None:
+    assert _resolve_supports({})[CONF_SUPPORTS_CURRENT_TEMPERATURE] is False
+
+
+def test_supports_current_temperature_explicit_true_without_sensor_allowed() -> None:
+    # The value can still be reported with climate.template.publish.
+    config: ConfigType = {CONF_SUPPORTS_CURRENT_TEMPERATURE: True}
+    assert _resolve_supports(config)[CONF_SUPPORTS_CURRENT_TEMPERATURE] is True
+
+
+def test_supports_current_temperature_false_with_sensor_rejected() -> None:
+    config: ConfigType = {
+        CONF_SENSOR: "some_sensor",
+        CONF_SUPPORTS_CURRENT_TEMPERATURE: False,
+    }
+    with pytest.raises(cv.Invalid, match="cannot be false"):
+        _resolve_supports(config)
+
+
+def test_supports_current_humidity_false_with_sensor_rejected() -> None:
+    config: ConfigType = {
+        CONF_HUMIDITY_SENSOR: "some_sensor",
+        CONF_SUPPORTS_CURRENT_HUMIDITY: False,
+    }
+    with pytest.raises(cv.Invalid, match="cannot be false"):
+        _resolve_supports(config)
+
+
+def test_two_point_derived_from_set_actions() -> None:
+    config: ConfigType = {
+        CONF_SET_TARGET_TEMPERATURE_LOW_ACTION: [{}],
+        CONF_SET_TARGET_TEMPERATURE_HIGH_ACTION: [{}],
+    }
+    assert _resolve_supports(config)[CONF_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE] is True
+
+
+def test_two_point_false_with_set_action_rejected() -> None:
+    config: ConfigType = {
+        CONF_SET_TARGET_TEMPERATURE_LOW_ACTION: [{}],
+        CONF_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE: False,
+    }
+    with pytest.raises(cv.Invalid, match="cannot be false"):
+        _resolve_supports(config)
+
+
+def test_target_humidity_derived_from_set_action() -> None:
+    config: ConfigType = {CONF_SET_TARGET_HUMIDITY_ACTION: [{}]}
+    assert _resolve_supports(config)[CONF_SUPPORTS_TARGET_HUMIDITY] is True
+
+
+def test_set_target_temperature_low_requires_high() -> None:
+    config: ConfigType = {CONF_SET_TARGET_TEMPERATURE_LOW_ACTION: [{}]}
+    with pytest.raises(cv.Invalid, match="must be used together"):
+        _validate_set_actions(config)
+
+
+def test_set_target_temperature_conflicts_with_two_point_actions() -> None:
+    config: ConfigType = {
+        CONF_SET_TARGET_TEMPERATURE_ACTION: [{}],
+        CONF_SET_TARGET_TEMPERATURE_LOW_ACTION: [{}],
+        CONF_SET_TARGET_TEMPERATURE_HIGH_ACTION: [{}],
+    }
+    with pytest.raises(cv.Invalid, match="cannot be used together"):
+        _validate_set_actions(config)
+
+
+def test_initial_state_target_temperature_rejected_with_two_point() -> None:
+    config: ConfigType = {
+        CONF_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE: True,
+        CONF_SUPPORTS_TARGET_HUMIDITY: False,
+        CONF_INITIAL_STATE: {CONF_TARGET_TEMPERATURE: 21.0},
+    }
+    with pytest.raises(cv.Invalid, match="is not available"):
+        _validate_initial_state(config)
+
+
+def test_initial_state_two_point_values_rejected_without_two_point() -> None:
+    config: ConfigType = {
+        CONF_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE: False,
+        CONF_SUPPORTS_TARGET_HUMIDITY: False,
+        CONF_INITIAL_STATE: {
+            CONF_TARGET_TEMPERATURE_LOW: 18.0,
+            CONF_TARGET_TEMPERATURE_HIGH: 24.0,
+        },
+    }
+    with pytest.raises(cv.Invalid, match="requires"):
+        _validate_initial_state(config)
+
+
+def test_initial_state_target_humidity_rejected_without_support() -> None:
+    config: ConfigType = {
+        CONF_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE: False,
+        CONF_SUPPORTS_TARGET_HUMIDITY: False,
+        CONF_INITIAL_STATE: {CONF_TARGET_HUMIDITY: 50},
+    }
+    with pytest.raises(cv.Invalid, match="requires"):
+        _validate_initial_state(config)
+
+
+def test_initial_state_matching_two_point_accepted() -> None:
+    config: ConfigType = {
+        CONF_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE: True,
+        CONF_SUPPORTS_TARGET_HUMIDITY: True,
+        CONF_INITIAL_STATE: {
+            CONF_TARGET_TEMPERATURE_LOW: 18.0,
+            CONF_TARGET_TEMPERATURE_HIGH: 24.0,
+            CONF_TARGET_HUMIDITY: 50,
+        },
+    }
+    assert _validate_initial_state(config) is config

tests/components/atm90e32/__init__.py

@@ -0,0 +1,5 @@
+from tests.testing_helpers import ComponentManifestOverride
+
+
+def override_manifest(manifest: ComponentManifestOverride) -> None:
+    manifest.dependencies = manifest.dependencies + ["sensor", "spi"]

tests/components/atm90e32/offset_register_verification_test.cpp

@@ -0,0 +1,62 @@
+#include <gtest/gtest.h>
+
+#include "esphome/components/atm90e32/atm90e32.h"
+
+namespace esphome::atm90e32::testing {
+
+TEST(ATM90E32OffsetRegisterVerification, AcceptsExactSignedReadback) {
+  EXPECT_TRUE(offset_register_value_matches(0x007B, 123));
+  EXPECT_TRUE(offset_register_value_matches(0xFF85, -123));
+}
+
+TEST(ATM90E32OffsetRegisterVerification, RejectsMismatchedReadback) {
+  EXPECT_FALSE(offset_register_value_matches(0x007C, 123));
+  EXPECT_FALSE(offset_register_value_matches(0xFF84, -123));
+}
+
+TEST(ATM90E32OffsetRestoreState, ReportsVerifiedStoredValuesAsRestored) {
+  const auto state = resolve_offset_restore_state(true, true, false);
+
+  EXPECT_TRUE(state.restored);
+  EXPECT_TRUE(state.values_verified);
+}
+
+TEST(ATM90E32OffsetRestoreState, ReportsVerifiedConfigFallbackAsNotRestored) {
+  const auto state = resolve_offset_restore_state(true, false, true);
+
+  EXPECT_FALSE(state.restored);
+  EXPECT_TRUE(state.values_verified);
+}
+
+TEST(ATM90E32OffsetRestoreState, ReportsFailedConfigFallbackAsUnverified) {
+  const auto state = resolve_offset_restore_state(true, false, false);
+
+  EXPECT_FALSE(state.restored);
+  EXPECT_FALSE(state.values_verified);
+}
+
+TEST(ATM90E32OffsetRestoreState, ReportsConfigWithoutStoredValuesAsNotRestored) {
+  const auto state = resolve_offset_restore_state(false, true, false);
+
+  EXPECT_FALSE(state.restored);
+  EXPECT_TRUE(state.values_verified);
+}
+
+TEST(ATM90E32OffsetPersistence, RollsBackStoredValuesOrZeroSentinel) {
+  const OffsetCalibration previous[3]{{1, -1}, {2, -2}, {3, -3}};
+  OffsetCalibration rollback[3]{};
+
+  prepare_offset_rollback(previous, true, rollback);
+  for (uint8_t phase = 0; phase < 3; phase++) {
+    EXPECT_EQ(rollback[phase].first_offset, previous[phase].first_offset);
+    EXPECT_EQ(rollback[phase].second_offset, previous[phase].second_offset);
+  }
+
+  prepare_offset_rollback(previous, false, rollback);
+  for (const auto &phase : rollback) {
+    EXPECT_EQ(phase.first_offset, 0);
+    EXPECT_EQ(phase.second_offset, 0);
+  }
+}
+
+}  // namespace esphome::atm90e32::testing

tests/components/climate/common.yaml

@@ -30,8 +30,7 @@ climate:
       - switch.turn_on: climate_heater_switch
       - switch.turn_off: climate_cooler_switch
   # Thermostat-based climate so climate.control: action variants get build
-  # coverage (bang_bang doesn't support fan modes, presets, etc.). Climate
-  # has no template platform, so thermostat is the right vehicle.
+  # coverage (bang_bang doesn't support fan modes, presets, etc.).
   - platform: thermostat
     id: climate_test_thermostat
     name: Test Thermostat

tests/components/cse7761/test.esp32-idf.yaml

@@ -3,6 +3,6 @@ substitutions:
   rx_pin: GPIO14
 
 packages:
-  uart_38400: !include ../../test_build_components/common/uart_38400/esp32-idf.yaml
+  uart_38400_even: !include ../../test_build_components/common/uart_38400_even/esp32-idf.yaml
 
 <<: !include common.yaml

tests/components/cse7761/test.esp8266-ard.yaml

@@ -3,6 +3,6 @@ substitutions:
   rx_pin: GPIO3
 
 packages:
-  uart_38400: !include ../../test_build_components/common/uart_38400/esp8266-ard.yaml
+  uart_38400_even: !include ../../test_build_components/common/uart_38400_even/esp8266-ard.yaml
 
 <<: !include common.yaml

tests/components/cse7761/test.rp2040-ard.yaml

@@ -3,6 +3,6 @@ substitutions:
   rx_pin: GPIO5
 
 packages:
-  uart_38400: !include ../../test_build_components/common/uart_38400/rp2040-ard.yaml
+  uart_38400_even: !include ../../test_build_components/common/uart_38400_even/rp2040-ard.yaml
 
 <<: !include common.yaml

tests/components/esp32_hosted/test-espnow.esp32-p4-idf.yaml

@@ -0,0 +1,5 @@
+# Exercises the ESP-NOW-over-hosted shim: on the ESP32-P4 host, esp32_hosted
+# supplies the esp_now_* symbols that the espnow component links against.
+packages:
+  esp32_hosted: !include common.yaml
+  espnow: !include ../espnow/common.yaml

tests/components/kamstrup_kmp/test.esp32-idf.yaml

@@ -1,4 +1,4 @@
 packages:
-  uart_1200: !include ../../test_build_components/common/uart_1200/esp32-idf.yaml
+  uart_1200_none_2stopbits: !include ../../test_build_components/common/uart_1200_none_2stopbits/esp32-idf.yaml
 
 <<: !include common.yaml

tests/components/kamstrup_kmp/test.esp8266-ard.yaml

@@ -3,6 +3,6 @@ substitutions:
   uart_rx_pin: GPIO3
 
 packages:
-  uart_1200: !include ../../test_build_components/common/uart_1200/esp8266-ard.yaml
+  uart_1200_none_2stopbits: !include ../../test_build_components/common/uart_1200_none_2stopbits/esp8266-ard.yaml
 
 <<: !include common.yaml

tests/components/noise/test_noise_handshake.cpp

@@ -68,6 +68,14 @@ class Initiator {
 
 static const uint8_t PROLOGUE[] = {'t', 'e', 's', 't', 'p', 'r', 'o', 'l', 'o', 'g', 'u', 'e'};
 
+// The context only points at the key and init() copies it before returning,
+// so a temporary context over a temporary key is safe within one call
+static NoiseContext ctx_for(const psk_t &psk) {
+  NoiseContext ctx;
+  ctx.set_psk(psk.data());
+  return ctx;
+}
+
 static psk_t make_psk(uint8_t seed) {
   psk_t psk;
   for (size_t i = 0; i < psk.size(); i++) {
@@ -102,7 +110,7 @@ TEST(NoiseResponderHandshakeTest, MessageMethodsErrorBeforeInit) {
 TEST(NoiseResponderHandshakeTest, FullHandshakeAndTransportRoundTrip) {
   const psk_t psk = make_psk(7);
   NoiseResponderHandshake responder;
-  ASSERT_EQ(responder.init(psk, PROLOGUE, sizeof(PROLOGUE)), 0);
+  ASSERT_EQ(responder.init(ctx_for(psk), PROLOGUE, sizeof(PROLOGUE)), 0);
   EXPECT_EQ(responder.action(), Action::ACTION_READ);
 
   Initiator initiator(psk, PROLOGUE, sizeof(PROLOGUE));
@@ -155,8 +163,8 @@ TEST(NoiseResponderHandshakeTest, ReInitRestartsHandshake) {
   // proves the restart took effect; the old state surviving would fail the
   // MAC here.
   NoiseResponderHandshake responder;
-  ASSERT_EQ(responder.init(make_psk(7), PROLOGUE, sizeof(PROLOGUE)), 0);
-  ASSERT_EQ(responder.init(make_psk(9), PROLOGUE, sizeof(PROLOGUE)), 0);
+  ASSERT_EQ(responder.init(ctx_for(make_psk(7)), PROLOGUE, sizeof(PROLOGUE)), 0);
+  ASSERT_EQ(responder.init(ctx_for(make_psk(9)), PROLOGUE, sizeof(PROLOGUE)), 0);
   EXPECT_EQ(responder.action(), Action::ACTION_READ);
 
   Initiator initiator(make_psk(9), PROLOGUE, sizeof(PROLOGUE));
@@ -168,7 +176,7 @@ TEST(NoiseResponderHandshakeTest, ReInitRestartsHandshake) {
 
 TEST(NoiseResponderHandshakeTest, WrongPskFailsWithMacFailure) {
   NoiseResponderHandshake responder;
-  ASSERT_EQ(responder.init(make_psk(7), PROLOGUE, sizeof(PROLOGUE)), 0);
+  ASSERT_EQ(responder.init(ctx_for(make_psk(7)), PROLOGUE, sizeof(PROLOGUE)), 0);
 
   Initiator initiator(make_psk(200), PROLOGUE, sizeof(PROLOGUE));
   uint8_t msg[MAX_HANDSHAKE_SIZE];
@@ -185,7 +193,7 @@ TEST(NoiseResponderHandshakeTest, MismatchedPrologueFailsWithMacFailure) {
   // tampered preamble must fail even with the right key.
   const psk_t psk = make_psk(7);
   NoiseResponderHandshake responder;
-  ASSERT_EQ(responder.init(psk, PROLOGUE, sizeof(PROLOGUE)), 0);
+  ASSERT_EQ(responder.init(ctx_for(psk), PROLOGUE, sizeof(PROLOGUE)), 0);
 
   static const uint8_t TAMPERED[] = {'x'};
   Initiator initiator(psk, TAMPERED, sizeof(TAMPERED));

tests/components/noise/test_noise_primitives.cpp

@@ -17,12 +17,17 @@ TEST(NoiseContextTest, AllZerosPskIsReserved) {
   EXPECT_FALSE(NoiseContext::is_all_zeros(psk));
 
   NoiseContext ctx;
+  psk_t loaded;
   EXPECT_FALSE(ctx.has_psk());
-  ctx.set_psk(zeros);
-  EXPECT_FALSE(ctx.has_psk());
-  ctx.set_psk(psk);
+  ctx.load_psk(loaded);
+  EXPECT_EQ(loaded, zeros);
+  ctx.set_psk(psk.data());
   EXPECT_TRUE(ctx.has_psk());
-  EXPECT_EQ(ctx.get_psk(), psk);
+  ctx.load_psk(loaded);
+  EXPECT_EQ(loaded, psk);
+  // Callers map the reserved key to nullptr; the context just stores what it is given
+  ctx.set_psk(nullptr);
+  EXPECT_FALSE(ctx.has_psk());
 }
 
 TEST(WireFormatTest, FrameHeaderIsIndicatorPlusBigEndianLength) {

tests/components/ota/api_key_offer.yaml

@@ -0,0 +1,12 @@
+wifi:
+  ssid: MySSID
+  password: password1
+
+api:
+  encryption:
+    key: "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8="
+
+ota:
+  - platform: esphome
+    port: 3290
+    password: "superlongpasswordthatnoonewillknow"

tests/components/ota/api_runtime_key.yaml

@@ -0,0 +1,10 @@
+wifi:
+  ssid: MySSID
+  password: password1
+
+api:
+  encryption:
+
+ota:
+  - platform: esphome
+    port: 3291

tests/components/ota/test-api_key_offer.esp32-idf.yaml

@@ -0,0 +1,2 @@
+packages:
+  ota: !include api_key_offer.yaml

tests/components/ota/test-api_key_offer.esp8266-ard.yaml

@@ -0,0 +1,2 @@
+packages:
+  ota: !include api_key_offer.yaml

tests/components/ota/test-api_runtime_key.esp32-idf.yaml

@@ -0,0 +1,2 @@
+packages:
+  ota: !include api_runtime_key.yaml

tests/components/ota/test-api_runtime_key.esp8266-ard.yaml

@@ -0,0 +1,2 @@
+packages:
+  ota: !include api_runtime_key.yaml

tests/components/pylontech/test.esp32-idf.yaml

@@ -3,6 +3,6 @@ substitutions:
   rx_pin: GPIO5
 
 packages:
-  uart: !include ../../test_build_components/common/uart/esp32-idf.yaml
+  uart_115200: !include ../../test_build_components/common/uart_115200/esp32-idf.yaml
 
 <<: !include common.yaml

tests/components/pylontech/test.esp8266-ard.yaml

@@ -3,6 +3,6 @@ substitutions:
   rx_pin: GPIO2
 
 packages:
-  uart: !include ../../test_build_components/common/uart/esp8266-ard.yaml
+  uart_115200: !include ../../test_build_components/common/uart_115200/esp8266-ard.yaml
 
 <<: !include common.yaml

tests/components/pylontech/test.rp2040-ard.yaml

@@ -3,6 +3,6 @@ substitutions:
   rx_pin: GPIO5
 
 packages:
-  uart: !include ../../test_build_components/common/uart/rp2040-ard.yaml
+  uart_115200: !include ../../test_build_components/common/uart_115200/rp2040-ard.yaml
 
 <<: !include common.yaml

tests/components/remote_transmitter/test.bk72xx-ard.yaml

@@ -2,7 +2,7 @@ remote_transmitter:
   id: xmitr
   pin: GPIO26
   carrier_duty_percent: 50%
-  # non_blocking is bk7231n/bk7238-only; the CI board is a BK7252
+  # non_blocking is bk7238-only; the CI board is a BK7252, so this builds the bit-bang path
 
 packages:
   buttons: !include common-buttons.yaml

tests/components/sdl/common.yaml

@@ -14,6 +14,15 @@ display:
       position:
         x: 100
         y: 100
+    snapshot_key: SDLK_F12
+
+  - platform: sdl
+    id: headless_display
+    headless: true
+    show_test_card: true
+    dimensions:
+      width: 320
+      height: 240
 
   - platform: sdl
     id: second_display
@@ -46,3 +55,21 @@ binary_sensor:
     sdl_id: sdl_sdl_display
     id: key_enter
     key: SDLK_RETURN
+
+esphome:
+  # A name of your own is only good for one snapshot - a second one under the same name fails
+  # rather than writing over the first - so these run once rather than on a repeating interval.
+  on_boot:
+    - delay: 2s
+    - snapshot.take:
+        id: headless_display
+        filename: test_card.bmp
+    - snapshot.take:
+        id: headless_display
+        filename: !lambda 'return "shot.bmp";'
+
+interval:
+  # A generated name has the time in it, so this one can repeat.
+  - interval: 10s
+    then:
+      - snapshot.take: sdl_sdl_display

tests/components/sdl/validate.host.yaml

@@ -0,0 +1,29 @@
+# Config-only test for the headless and screenshot options. The combinations that must be
+# rejected are covered by tests/component_tests/sdl/test_sdl.py; this file checks that the
+# accepted forms validate together.
+host:
+  mac_address: "62:23:45:AF:B3:DD"
+
+display:
+  - platform: sdl
+    id: headless_display
+    headless: true
+    dimensions: 320x240
+
+  - platform: sdl
+    id: windowed_display
+    dimensions: 320x240
+    snapshot_key: SDLK_F12
+
+binary_sensor:
+  - platform: sdl
+    sdl_id: windowed_display
+    id: key_up
+    key: SDLK_UP
+
+interval:
+  - interval: 10s
+    then:
+      - snapshot.take:
+          id: headless_display
+          filename: periodic.bmp

tests/components/snapshot/common.yaml

@@ -0,0 +1,34 @@
+display:
+  - platform: snapshot
+    id: snapshot_display
+    update_interval: 1s
+    show_test_card: true
+    # An odd width exercises the row padding in the BMP writer
+    dimensions:
+      width: 101
+      height: 64
+
+  - platform: snapshot
+    id: snapshot_rotated
+    rotation: 90
+    dimensions: 320x240
+    lambda: |-
+      it.filled_rectangle(0, 0, 40, 20, Color(0xFF, 0x80, 0x00));
+
+esphome:
+  # A name of your own is only good for one snapshot - a second one under the same name fails
+  # rather than writing over the first - so these run once rather than on a repeating interval.
+  on_boot:
+    - delay: 2s
+    - snapshot.take:
+        id: snapshot_display
+        filename: test_card.bmp
+    - snapshot.take:
+        id: snapshot_rotated
+        filename: !lambda 'return "rotated.bmp";'
+
+interval:
+  # A generated name has the time in it, so this one can repeat.
+  - interval: 10s
+    then:
+      - snapshot.take: snapshot_display

tests/components/snapshot/test.host.yaml

@@ -0,0 +1,5 @@
+host:
+  mac_address: "62:23:45:AF:B3:DE"
+
+packages:
+  snapshot: !include common.yaml

tests/components/teleinfo/test.esp32-idf.yaml

@@ -3,6 +3,6 @@ substitutions:
   rx_pin: GPIO5
 
 packages:
-  uart: !include ../../test_build_components/common/uart/esp32-idf.yaml
+  uart_1200_even_7bits: !include ../../test_build_components/common/uart_1200_even_7bits/esp32-idf.yaml
 
 <<: !include common.yaml

tests/components/teleinfo/test.esp8266-ard.yaml

@@ -3,6 +3,6 @@ substitutions:
   rx_pin: GPIO2
 
 packages:
-  uart: !include ../../test_build_components/common/uart/esp8266-ard.yaml
+  uart_1200_even_7bits: !include ../../test_build_components/common/uart_1200_even_7bits/esp8266-ard.yaml
 
 <<: !include common.yaml

tests/components/teleinfo/test.rp2040-ard.yaml

@@ -3,6 +3,6 @@ substitutions:
   rx_pin: GPIO5
 
 packages:
-  uart: !include ../../test_build_components/common/uart/rp2040-ard.yaml
+  uart_1200_even_7bits: !include ../../test_build_components/common/uart_1200_even_7bits/rp2040-ard.yaml
 
 <<: !include common.yaml

tests/components/teleinfo/validate-standard.esp32-idf.yaml

@@ -0,0 +1,14 @@
+packages:
+  uart_9600_even_7bits: !include ../../test_build_components/common/uart_9600_even_7bits/esp32-idf.yaml
+
+teleinfo:
+  id: test_teleinfo_standard
+  historical_mode: false
+  update_interval: 60s
+
+sensor:
+  - platform: teleinfo
+    name: sinsts
+    tag_name: SINSTS
+    teleinfo_id: test_teleinfo_standard
+    unit_of_measurement: VA

tests/components/template/common-base.yaml

@@ -25,6 +25,27 @@ esphome:
         away: !lambda "return true;"
         is_on: !lambda "return false;"
 
+    - climate.template.publish:
+        id: template_climate
+        current_temperature: 21.0
+        mode: HEAT
+        fan_mode: AUTO
+        swing_mode: "OFF"
+        preset: NONE
+        target_temperature: 22.0
+
+    # Templated
+    - climate.template.publish:
+        id: template_climate
+        current_temperature: !lambda "return 21.5f;"
+        mode: !lambda "return climate::CLIMATE_MODE_COOL;"
+        target_temperature: !lambda "return 23.0f;"
+
+    - climate.template.publish:
+        id: template_climate_custom_modes
+        custom_fan_mode: "turbo"
+        custom_preset: "eco_plus"
+
     # Test C++ API: set_template() with stateless lambda (no captures)
     # NOTE: set_template() is not intended to be a public API, but we test it to ensure it doesn't break.
     - lambda: |-
@@ -513,6 +534,98 @@ alarm_control_panel:
     codes:
       - "1234"
 
+climate:
+  - platform: template
+    id: template_climate
+    name: "Template Climate"
+    optimistic: true
+    sensor: template_template_sens
+    supports_action: true
+    supports_current_humidity: true
+    restore_mode: NO_RESTORE
+    initial_state:
+      mode: HEAT
+      target_temperature: 21.0
+      fan_mode: LOW
+    supported_modes:
+      - "OFF"
+      - HEAT
+      - COOL
+    supported_fan_modes:
+      - AUTO
+      - LOW
+      - HIGH
+    supported_swing_modes:
+      - "OFF"
+      - VERTICAL
+    supported_presets:
+      - NONE
+      - ECO
+    visual:
+      min_temperature: 16.0
+      max_temperature: 30.0
+      temperature_step: 0.5
+    set_mode_action:
+      - logger.log:
+          format: "set_mode_action %d"
+          args: ["(int) x"]
+    set_target_temperature_action:
+      - logger.log:
+          format: "set_target_temperature_action %.1f"
+          args: ["x"]
+    set_target_humidity_action:
+      - logger.log:
+          format: "set_target_humidity_action %.1f"
+          args: ["x"]
+    set_fan_mode_action:
+      - logger.log:
+          format: "set_fan_mode_action %d"
+          args: ["(int) x"]
+    set_swing_mode_action:
+      - logger.log:
+          format: "set_swing_mode_action %d"
+          args: ["(int) x"]
+    set_preset_action:
+      - logger.log:
+          format: "set_preset_action %d"
+          args: ["(int) x"]
+    on_control:
+      - logger.log: "on_control fired"
+    on_state:
+      - logger.log: "on_state fired"
+
+  - platform: template
+    id: template_climate_custom_modes
+    name: "Template Climate Custom Modes"
+    optimistic: true
+    sensor: template_template_sens
+    supported_modes:
+      - "OFF"
+      - HEAT
+    custom_fan_modes:
+      - turbo
+      - silent
+      - eco
+    custom_presets:
+      - eco_plus
+      - power_save
+      - max
+    set_custom_fan_mode_action:
+      - logger.log:
+          format: "set_custom_fan_mode_action %s"
+          args: ["x.c_str()"]
+    set_custom_preset_action:
+      - logger.log:
+          format: "set_custom_preset_action %s"
+          args: ["x.c_str()"]
+    initial_state:
+      custom_fan_mode: eco
+      custom_preset: max
+    visual:
+      min_temperature: 16.0
+      max_temperature: 30.0
+      temperature_step: 0.5
+
 water_heater:
   - platform: template
     id: template_water_heater

tests/components/tuya/test-no-network.bk72xx-ard.yaml

@@ -0,0 +1,29 @@
+# Tuya without any network component (no wifi/ethernet/api), as used on
+# serial-only or BLE-only Tuya MCU boards. Regression test for
+# https://github.com/esphome/esphome/issues/18942
+substitutions:
+  status_pin: P6
+
+packages:
+  uart: !include ../../test_build_components/common/uart/bk72xx-ard.yaml
+
+tuya:
+  status_pin: ${status_pin}
+
+binary_sensor:
+  - platform: tuya
+    id: tuya_presence
+    sensor_datapoint: 101
+
+sensor:
+  - platform: tuya
+    id: tuya_light_intensity
+    sensor_datapoint: 103
+
+number:
+  - platform: tuya
+    id: tuya_far_detection
+    number_datapoint: 109
+    min_value: 0
+    max_value: 600
+    step: 1

tests/components/wifi/common.yaml

@@ -14,6 +14,7 @@ esphome:
           condition: wifi.ap_active
           then:
             - logger.log: "WiFi AP is active!"
+      - wifi.roam
 
 wifi:
   networks:

tests/integration/README.md

@@ -21,6 +21,13 @@ The `yaml_config` fixture automatically loads YAML configurations based on the t
 - The fixture file must exist or the test will fail with a clear error message
 - The fixture automatically injects a dynamic port number into the API configuration
 
+Tests marked `@pytest.mark.shared_yaml("name")` load `fixtures/name.yaml` instead
+of the test-named file and compile it in a shared, hash-keyed build directory, so
+the whole group pays one full compile and each test only a relink. The marker
+argument must be a single-line string literal (CI test selection maps fixtures to
+test files by scanning for it), and marked tests must hand the `yaml_config`
+content to `run_compiled` unmodified.
+
 ### Key Fixtures
 
 - `run_compiled` - Combines write, compile, and run operations into a single context manager

tests/integration/artifact_utils.py

@@ -0,0 +1,26 @@
+"""Shared utilities for ESPHome integration tests - keeping output from failing tests."""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+#: Where a failing test leaves output for someone to look at afterwards. pytest's own
+#: temporary folder is no use on a CI runner, which throws the whole workspace away when
+#: the job ends; the workflow uploads this folder instead when a job fails.
+ARTIFACT_DIR = Path(__file__).resolve().parents[2] / "test_artifacts"
+
+
+def keep_artifact(name: str, data: bytes) -> Path:
+    """Write ``data`` where it can still be read after the run, and return the path.
+
+    Args:
+        name: File name to write under the artifact folder.
+        data: Contents to write.
+
+    Returns:
+        The full path written.
+    """
+    ARTIFACT_DIR.mkdir(parents=True, exist_ok=True)
+    path = ARTIFACT_DIR / name
+    path.write_bytes(data)
+    return path

tests/integration/bmp_utils.py

@@ -0,0 +1,161 @@
+"""Shared utilities for ESPHome integration tests - reading BMP snapshots."""
+
+from __future__ import annotations
+
+import asyncio
+from collections.abc import Awaitable, Callable
+from dataclasses import dataclass
+from pathlib import Path
+import struct
+
+# Size of the smallest BMP header pair (file header plus BITMAPINFOHEADER).
+_MIN_HEADER_SIZE = 54
+
+# How long capture_when_drawn() keeps asking for a picture with something on it.
+DRAW_TIMEOUT = 15.0
+
+
+@dataclass(frozen=True)
+class Bmp:
+    """A decoded BMP image."""
+
+    width: int
+    height: int
+    bits: int
+    #: Pixel data with the per row padding stripped, so it depends only on the image itself.
+    pixels: bytes
+
+
+class NotABmpError(Exception):
+    """The data is not a BMP at all, as opposed to a BMP that is still being written."""
+
+
+def parse_bmp(data: bytes) -> Bmp | None:
+    """Decode a BMP, or return None if the data is not a complete image yet.
+
+    Raises:
+        NotABmpError: If the data cannot become a valid BMP however much more is appended.
+    """
+    # Writes go to the file in order, so a short read is always a prefix of what will be there.
+    # Anything wrong in a prefix we have already read is wrong for good, and worth saying now
+    # rather than reporting as a timeout later.
+    if len(data) >= 2 and data[:2] != b"BM":
+        raise NotABmpError(f"expected a BMP, got {data[:2]!r}")
+    if len(data) < _MIN_HEADER_SIZE:
+        return None
+    file_size = struct.unpack_from("<I", data, 2)[0]
+    offset = struct.unpack_from("<I", data, 10)[0]
+    width, height = struct.unpack_from("<ii", data, 18)
+    bits = struct.unpack_from("<H", data, 28)[0]
+    rows = abs(height)
+    row_size = ((width * bits + 31) // 32) * 4
+    if width <= 0 or rows == 0 or bits == 0 or offset < _MIN_HEADER_SIZE:
+        raise NotABmpError(
+            f"BMP header makes no sense: {width}x{height}, {bits} bits, "
+            f"pixels at offset {offset}"
+        )
+    if file_size < offset + row_size * rows:
+        raise NotABmpError(
+            f"BMP header claims {file_size} bytes, too few for {width}x{rows} "
+            f"at {bits} bits"
+        )
+    if len(data) < file_size:
+        return None
+    used = width * bits // 8
+    pixels = b"".join(
+        data[offset + row * row_size : offset + row * row_size + used]
+        for row in range(rows)
+    )
+    return Bmp(width=width, height=rows, bits=bits, pixels=pixels)
+
+
+async def wait_for_bmp(path: Path, timeout: float = 5.0) -> Bmp:
+    """Wait for a complete BMP file to appear at ``path`` and return it.
+
+    The file is created before any of its contents are written, so waiting for it to exist is
+    not enough - a read that wins the race sees a truncated image. Keep reading until the
+    headers say the whole image is there.
+
+    Args:
+        path: The file to wait for.
+        timeout: Maximum time to wait in seconds.
+
+    Returns:
+        The decoded image.
+
+    Raises:
+        AssertionError: If no complete image is readable within ``timeout``.
+        NotABmpError: If what was written is not a BMP. This is reported as soon as it is
+            seen, so a device that writes the wrong thing is named for what it did rather
+            than waiting out the timeout.
+    """
+    loop = asyncio.get_running_loop()
+    deadline = loop.time() + timeout
+    while True:
+        try:
+            data = path.read_bytes()
+        except FileNotFoundError:
+            data = b""
+        if (image := parse_bmp(data)) is not None:
+            return image
+        if loop.time() >= deadline:
+            break
+        await asyncio.sleep(0.05)
+    if not data:
+        raise AssertionError(f"no snapshot appeared at {path} within {timeout}s")
+    raise AssertionError(
+        f"{path} was still incomplete after {timeout}s ({len(data)} bytes)"
+    )
+
+
+def is_blank(image: Bmp) -> bool:
+    """True if every pixel of the image is the same colour.
+
+    Whole pixels are counted rather than byte values: a plain background is usually made of more
+    than one distinct byte, so counting bytes would find several of them in a blank screen.
+    """
+    return len({image.pixels[i : i + 3] for i in range(0, len(image.pixels), 3)}) <= 1
+
+
+async def capture_when_drawn(
+    take: Callable[[str], Awaitable[None]],
+    directory: Path,
+    prefix: str = "drawn",
+    timeout: float = DRAW_TIMEOUT,
+) -> tuple[Bmp, Path]:
+    """Ask for snapshots until one has something drawn on it, and return it and where it went.
+
+    A display holds one flat colour until it first draws, which is one update interval after it
+    starts - long enough that a test connecting over the API can easily get in first. Capturing
+    once and hoping would compare a blank screen against whatever the test expects, reporting a
+    drawing fault where the real trouble was timing.
+
+    Args:
+        take: Asks the device for a snapshot under the name it is given.
+        directory: Where the device writes them.
+        prefix: Start of the names asked for. Each attempt needs its own, because a snapshot never
+            writes over a file that is already there.
+        timeout: How long to keep asking.
+
+    Returns:
+        The first image that is not one flat colour, and the path it was read from.
+
+    Raises:
+        AssertionError: If nothing had been drawn within ``timeout``.
+    """
+    loop = asyncio.get_running_loop()
+    deadline = loop.time() + timeout
+    attempt = 0
+    while True:
+        attempt += 1
+        path = directory / f"{prefix}-{attempt}.bmp"
+        await take(path.name)
+        image = await wait_for_bmp(path)
+        if not is_blank(image):
+            return image, path
+        if loop.time() >= deadline:
+            raise AssertionError(
+                f"the screen was still a single flat colour after {timeout}s and "
+                f"{attempt} captures - nothing was drawn"
+            )
+        await asyncio.sleep(0.5)

tests/integration/conftest.py

@@ -4,17 +4,22 @@ from __future__ import annotations
 
 import asyncio
 from collections.abc import AsyncGenerator, Callable, Generator
-from contextlib import AbstractAsyncContextManager, asynccontextmanager
+from contextlib import AbstractAsyncContextManager, asynccontextmanager, suppress
 import fcntl
+from functools import cache
+import hashlib
 import logging
 import os
 from pathlib import Path
 import platform
+import re
+import shutil
 import signal
 import socket
 import subprocess
 import sys
 import tempfile
+import time
 from typing import TextIO
 
 from aioesphomeapi import APIClient, APIConnectionError, LogParser, ReconnectLogic
@@ -23,7 +28,13 @@ import pytest_asyncio
 
 import esphome.config
 from esphome.core import CORE
-from esphome.helpers import get_usable_cpu_count
+from esphome.helpers import (
+    get_usable_cpu_count,
+    read_file,
+    rmtree,
+    write_file,
+    write_file_if_changed,
+)
 from esphome.platformio.toolchain import get_idedata
 
 from .const import (
@@ -56,6 +67,21 @@ import pty  # not available on Windows
 pytest.register_assert_rewrite("tests.integration.entity_utils")
 
 
+def pytest_configure(config: pytest.Config) -> None:
+    config.addinivalue_line(
+        "markers",
+        "shared_yaml(name): load fixtures/<name>.yaml and compile it in a shared, "
+        "hash-keyed incremental build directory",
+    )
+
+
+FIXTURES_DIR = Path(__file__).parent / "fixtures"
+REPO_ROOT = Path(__file__).resolve().parent.parent.parent
+
+# CI caches parts of this path; keep in sync with ci.yml integration-tests.
+INTEGRATION_TESTS_ROOT = Path.home() / ".esphome-integration-tests"
+
+
 def _get_platformio_env(cache_dir: Path) -> dict[str, str]:
     """Get environment variables for PlatformIO with shared cache."""
     env = os.environ.copy()
@@ -78,7 +104,7 @@ def _get_platformio_env(cache_dir: Path) -> dict[str, str]:
         )
     # Compile with THIS tree's esphome sources, not wherever the venv's editable
     # install points (which may be a different git worktree or checkout).
-    repo_root = str(Path(__file__).resolve().parent.parent.parent)
+    repo_root = str(REPO_ROOT)
     existing = env.get("PYTHONPATH")
     env["PYTHONPATH"] = f"{repo_root}{os.pathsep}{existing}" if existing else repo_root
     return env
@@ -88,8 +114,7 @@ def _get_platformio_env(cache_dir: Path) -> dict[str, str]:
 def shared_platformio_cache() -> Generator[Path]:
     """Initialize a shared PlatformIO cache for all integration tests."""
     # Use a dedicated directory for integration tests to avoid conflicts.
-    # CI caches parts of this path; keep in sync with ci.yml integration-tests.
-    test_cache_dir = Path.home() / ".esphome-integration-tests"
+    test_cache_dir = INTEGRATION_TESTS_ROOT
     cache_dir = test_cache_dir / "platformio"
 
     # Use a lock file in the home directory to ensure only one process initializes the cache
@@ -112,7 +137,9 @@ def shared_platformio_cache() -> Generator[Path]:
                 init_dir = Path(tmpdir)
                 fixture_path = Path(__file__).parent / "fixtures" / "cache_init.yaml"
                 config_path = init_dir / "cache_init.yaml"
-                config_path.write_text(fixture_path.read_text())
+                config_path.write_text(
+                    fixture_path.read_text(encoding="utf-8"), encoding="utf-8"
+                )
 
                 # Run compilation to populate the cache
                 # We must succeed here to avoid race conditions where multiple
@@ -181,21 +208,29 @@ def unused_tcp_port(reserved_tcp_port: tuple[int, socket.socket]) -> int:
     return reserved_tcp_port[0]
 
 
+@pytest.fixture(autouse=True)
+def isolated_preferences(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> Path:
+    """Give every test its own host prefs dir; prefs are keyed only by device
+    name, which tests sharing a fixture also share."""
+    prefdir = tmp_path / "prefs"
+    monkeypatch.setenv("ESPHOME_PREFDIR", str(prefdir))
+    return prefdir
+
+
 @pytest_asyncio.fixture
 async def yaml_config(request: pytest.FixtureRequest, unused_tcp_port: int) -> str:
     """Load YAML configuration based on test name."""
-    # Get the test function name
-    test_name: str = request.node.name
-    # Extract the base test name (remove test_ prefix and any parametrization)
-    base_name = test_name.replace("test_", "").partition("[")[0]
+    shared_name = _shared_yaml_name(request)
+    # Base test name: test_ prefix and any parametrization stripped
+    base_name = shared_name or request.node.name.replace("test_", "").partition("[")[0]
 
     # Load the fixture file
-    fixture_path = Path(__file__).parent / "fixtures" / f"{base_name}.yaml"
+    fixture_path = FIXTURES_DIR / f"{base_name}.yaml"
     if not fixture_path.exists():
         raise FileNotFoundError(f"Fixture file not found: {fixture_path}")
 
     loop = asyncio.get_running_loop()
-    content = await loop.run_in_executor(None, fixture_path.read_text)
+    content = await loop.run_in_executor(None, read_file, fixture_path)
 
     # Replace the port in the config if it contains api section
     if "api:" in content:
@@ -219,11 +254,13 @@ async def yaml_config(request: pytest.FixtureRequest, unused_tcp_port: int) -> s
 
     # Replace external component path placeholder if present
     if "EXTERNAL_COMPONENT_PATH" in content:
-        external_components_path = str(
-            Path(__file__).parent / "fixtures" / "external_components"
-        )
+        external_components_path = str(FIXTURES_DIR / "external_components")
         content = content.replace("EXTERNAL_COMPONENT_PATH", external_components_path)
 
+    if shared_name is not None:
+        # _compile verifies the marked test compiles this content unmodified
+        request.node._shared_yaml_content = content
+
     return content
 
 
@@ -233,24 +270,218 @@ async def write_yaml_config(
 ) -> AsyncGenerator[ConfigWriter]:
     """Write YAML configuration to a file."""
     # Get the test name for default filename
-    test_name = request.node.name
-    base_name = test_name.replace("test_", "").split("[")[0]
+    base_name = request.node.name.replace("test_", "").partition("[")[0]
 
     async def _write_config(content: str, filename: str | None = None) -> Path:
         if filename is None:
             filename = f"{base_name}.yaml"
         config_path = integration_test_dir / filename
         loop = asyncio.get_running_loop()
-        await loop.run_in_executor(None, config_path.write_text, content)
+        await loop.run_in_executor(None, write_file, config_path, content)
         return config_path
 
     yield _write_config
 
 
+# Deliberately not CI-cached (ci.yml caches only platformio/ subpaths); stale
+# dirs for a fixture are pruned when its content hash changes.
+SHARED_BUILDS_ROOT = INTEGRATION_TESTS_ROOT / "builds"
+
+# In the dir name (not just the hash) so pruning stays inside this checkout
+_REPO_KEY = hashlib.sha256(str(REPO_ROOT).encode()).hexdigest()[:8]
+
+# Give a contended shared build lock time for a full cold compile ahead of us
+_SHARED_LOCK_TIMEOUT_S = 900
+_SHARED_LOCK_POLL_S = 0.1
+_SHARED_LOCK_REPORT_S = 30
+
+# Reclaims dirs orphaned by fixture renames or deleted checkouts
+_STALE_BUILD_MAX_AGE_S = 30 * 24 * 3600
+
+# ELF path per shared build dir; constant once compiled, so resolve it only once
+_shared_elf_paths: dict[Path, Path] = {}
+
+# Dirs this process already swept; pruning is session-scoped work
+_pruned_dirs: set[Path] = set()
+
+
+def _shared_yaml_name(request: pytest.FixtureRequest) -> str | None:
+    """Name passed to the shared_yaml marker, or None when unmarked."""
+    marker = request.node.get_closest_marker("shared_yaml")
+    if marker is None:
+        return None
+    # Exactly one \w+ positional arg: the name doubles as a build dir
+    # component, and CI test selection (script/helpers.py) parses the same shape
+    if (
+        len(marker.args) != 1
+        or marker.kwargs
+        or not re.fullmatch(r"\w+", str(marker.args[0]))
+    ):
+        raise ValueError(
+            "shared_yaml marker requires exactly one \\w+ fixture name literal"
+        )
+    return marker.args[0]
+
+
+def _shared_build_prefix(name: str) -> str:
+    return f"{name}-{_REPO_KEY}-"
+
+
+@cache
+def _shared_build_dir(name: str) -> Path:
+    """Dir keyed by checkout and fixture source, before per-test injections."""
+    key = hashlib.sha256((FIXTURES_DIR / f"{name}.yaml").read_bytes()).hexdigest()[:16]
+    return SHARED_BUILDS_ROOT / (_shared_build_prefix(name) + key)
+
+
+def _read_stamp(stamp: Path, shared_dir: Path) -> Path | None:
+    """ELF path recorded by the last completed compile, or None."""
+    try:
+        text = stamp.read_text(encoding="utf-8").strip()
+    except FileNotFoundError:
+        return None
+    except OSError as err:
+        print(f"Cannot read {stamp}: {err}")
+        return None
+    if not text:
+        print(f"Ignoring empty stamp {stamp}")
+        return None
+    built = Path(text)
+    # Never trust a stamp pointing outside its own build dir as an unlink target
+    if shared_dir.resolve() in built.resolve().parents:
+        return built
+    print(f"Ignoring stamp {stamp} pointing outside {shared_dir}")
+    return None
+
+
+def _unused_since(stale: Path, cutoff: float) -> bool:
+    """Whether a build dir looks untouched since cutoff; unknown counts as used."""
+    # Newest of the .built stamp (rewritten by every completed compile) and the
+    # dir itself (freshened by a worker claiming the dir before locking)
+    newest: float | None = None
+    for probe in (stale / ".built", stale):
+        try:
+            mtime = probe.stat().st_mtime
+        except FileNotFoundError:
+            continue
+        except NotADirectoryError:
+            return True  # a stray file where a dir should be; reclaimable
+        except OSError as err:
+            print(f"Cannot age-probe {stale}: {err}")
+            return False  # unknown never authorizes deletion
+        newest = mtime if newest is None else max(newest, mtime)
+    return newest is not None and newest < cutoff
+
+
+def _prune_stale_builds(name: str, keep: Path) -> None:
+    """Remove outdated build dirs (blocking, run in executor): this checkout's
+    other dirs for the fixture, plus anything untouched for 30 days. Tolerates
+    other workers pruning the same dirs concurrently."""
+    cutoff = time.time() - _STALE_BUILD_MAX_AGE_S
+    prefix = _shared_build_prefix(name)
+    for stale in SHARED_BUILDS_ROOT.iterdir():
+        if stale == keep:
+            continue
+        same_fixture = stale.name.startswith(prefix)
+        if not same_fixture and not _unused_since(stale, cutoff):
+            continue
+        # Creating .lock bumps the dir mtime, so remember whether the re-probe
+        # under the lock can trust it
+        lock_preexisting = (stale / ".lock").exists()
+        try:
+            lock_file = (stale / ".lock").open("w")
+        except FileNotFoundError:
+            continue  # pruned by another worker meanwhile
+        except NotADirectoryError:
+            print(f"Removing stray file {stale}")
+            stale.unlink(missing_ok=True)
+            continue
+        except OSError as err:
+            print(f"Cannot prune {stale}: {err}")
+            continue
+        with lock_file:
+            try:
+                fcntl.flock(lock_file.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
+            except BlockingIOError:
+                continue  # still in use by another run
+            # Re-probe under the lock: a worker freshens its dir before
+            # locking, so a just-claimed dir no longer looks unused. A dir
+            # whose .lock we just created cannot be held by anyone, and our
+            # own open bumped its mtime, so its pre-open probe stands
+            if (
+                lock_preexisting
+                and not same_fixture
+                and not _unused_since(stale, cutoff)
+            ):
+                continue
+            # rmtree tolerates races; a leftover partial tree only costs a
+            # rebuild, since the ELF is deleted before every compile
+            try:
+                rmtree(stale)
+            except OSError as err:
+                print(f"Failed to prune {stale}: {err}")
+
+
+async def _run_esphome_compile(
+    config_path: Path, cwd: Path, env: dict[str, str]
+) -> None:
+    """Run `esphome compile`, retrying up to 3 times on a segfault."""
+    max_retries = 3
+    for attempt in range(max_retries):
+        # Compile using subprocess, inheriting stdout/stderr to show progress
+        proc = await asyncio.create_subprocess_exec(
+            sys.executable,
+            "-m",
+            "esphome",
+            "compile",
+            str(config_path),
+            cwd=cwd,
+            stdout=None,  # Inherit stdout
+            stderr=None,  # Inherit stderr
+            stdin=asyncio.subprocess.DEVNULL,
+            # Start in a new process group to isolate signal handling
+            start_new_session=True,
+            env=env,
+            close_fds=False,
+        )
+        await proc.wait()
+
+        if proc.returncode == 0:
+            break
+        if proc.returncode == -11 and attempt < max_retries - 1:
+            # Segfault (-11 = SIGSEGV), retry
+            print(
+                f"Compilation segfaulted (attempt {attempt + 1}/{max_retries}), retrying..."
+            )
+            await asyncio.sleep(1)  # Brief pause before retry
+            continue
+        raise RuntimeError(
+            f"Failed to compile {config_path}, return code: {proc.returncode}. "
+            f"Run with 'pytest -s' to see compilation output."
+        )
+
+
+def _resolve_compiled_binary(config_path: Path) -> Path:
+    """Load the config to learn the compiled ELF path (blocking, run in executor)."""
+    CORE.reset()  # Reset CORE state between test runs
+    CORE.config_path = config_path
+    config = esphome.config.read_config(
+        {"command": "compile", "config": str(config_path)}
+    )
+    if config is None:
+        raise RuntimeError(f"Failed to read config from {config_path}")
+    idedata = get_idedata(config)
+    binary_path = Path(idedata.firmware_elf_path)
+    if not binary_path.exists():
+        raise RuntimeError(f"Compiled binary not found at {binary_path}")
+    return binary_path
+
+
 @pytest_asyncio.fixture
 async def compile_esphome(
     integration_test_dir: Path,
     shared_platformio_cache: Path,
+    request: pytest.FixtureRequest,
 ) -> AsyncGenerator[CompileFunction]:
     """Compile an ESPHome configuration and return the binary path."""
 
@@ -258,66 +489,96 @@ async def compile_esphome(
         # Use the shared PlatformIO cache for faster compilation
         # This avoids re-downloading dependencies for each test
         env = _get_platformio_env(shared_platformio_cache)
-
-        # Retry compilation up to 3 times if we get a segfault
-        max_retries = 3
-        for attempt in range(max_retries):
-            # Compile using subprocess, inheriting stdout/stderr to show progress
-            proc = await asyncio.create_subprocess_exec(
-                sys.executable,
-                "-m",
-                "esphome",
-                "compile",
-                str(config_path),
-                cwd=integration_test_dir,
-                stdout=None,  # Inherit stdout
-                stderr=None,  # Inherit stderr
-                stdin=asyncio.subprocess.DEVNULL,
-                # Start in a new process group to isolate signal handling
-                start_new_session=True,
-                env=env,
-                close_fds=False,
-            )
-            await proc.wait()
-
-            if proc.returncode == 0:
-                # Success!
-                break
-            if proc.returncode == -11 and attempt < max_retries - 1:
-                # Segfault (-11 = SIGSEGV), retry
-                print(
-                    f"Compilation segfaulted (attempt {attempt + 1}/{max_retries}), retrying..."
-                )
-                await asyncio.sleep(1)  # Brief pause before retry
-                continue
-            # Other error or final retry
-            raise RuntimeError(
-                f"Failed to compile {config_path}, return code: {proc.returncode}. "
-                f"Run with 'pytest -s' to see compilation output."
-            )
-
-        # Load the config to get idedata (blocking call, must use executor)
         loop = asyncio.get_running_loop()
 
-        def _read_config_and_get_binary():
-            CORE.reset()  # Reset CORE state between test runs
-            CORE.config_path = config_path
-            config = esphome.config.read_config(
-                {"command": "compile", "config": str(config_path)}
+        name = _shared_yaml_name(request)
+        if name is None:
+            await _run_esphome_compile(config_path, integration_test_dir, env)
+            return await loop.run_in_executor(
+                None, _resolve_compiled_binary, config_path
             )
-            if config is None:
-                raise RuntimeError(f"Failed to read config from {config_path}")
 
-            # Get the compiled binary path
-            idedata = get_idedata(config)
-            return Path(idedata.firmware_elf_path)
-
-        binary_path = await loop.run_in_executor(None, _read_config_and_get_binary)
-
-        if not binary_path.exists():
-            raise RuntimeError(f"Compiled binary not found at {binary_path}")
-
-        return binary_path
+        # Shared fixture: build in a hash-keyed dir so tests sharing a config
+        # pay one full compile and later only a main.cpp (port) rebuild + relink
+        shared_dir = _shared_build_dir(name)
+        shared_dir.mkdir(parents=True, exist_ok=True)
+        # Freshen the dir before locking so a concurrent age sweep, which
+        # re-probes under the lock, never reaps a dir a worker just claimed;
+        # if a peer reaped it already, the guarded lock open recreates it
+        with suppress(FileNotFoundError):
+            os.utime(shared_dir)
+        if shared_dir not in _pruned_dirs:
+            _pruned_dirs.add(shared_dir)
+            await loop.run_in_executor(None, _prune_stale_builds, name, shared_dir)
+        shared_config = shared_dir / f"{name}.yaml"
+        private_binary = integration_test_dir / f"{name}.elf"
+        content = await loop.run_in_executor(None, read_file, config_path)
+        if content != getattr(request.node, "_shared_yaml_content", None):
+            # The dir is keyed by the fixture source; a mutated config would be
+            # cached under a hash that does not describe it
+            raise RuntimeError(
+                "shared_yaml tests must compile the yaml_config content unmodified"
+            )
+        # flock serializes concurrent xdist workers; closing the fd releases it.
+        # Hand-rolled rather than filelock.FileLock: non-blocking retries keep
+        # the wait cancellable, while a blocking acquire in an executor thread
+        # would survive test cancellation holding the fd
+        try:
+            lock_file = (shared_dir / ".lock").open("w")
+        except FileNotFoundError:
+            # A peer run pruning divergent hashes reaped the dir between our
+            # mkdir and this open; recreate it and pay a full rebuild
+            shared_dir.mkdir(parents=True, exist_ok=True)
+            lock_file = (shared_dir / ".lock").open("w")
+        with lock_file:
+            start = time.monotonic()
+            last_report = start
+            while True:
+                try:
+                    fcntl.flock(lock_file.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
+                    break
+                except BlockingIOError:
+                    now = time.monotonic()
+                    if now - start > _SHARED_LOCK_TIMEOUT_S:
+                        raise RuntimeError(
+                            f"Timed out waiting for the {shared_dir} lock"
+                        ) from None
+                    if now - last_report >= _SHARED_LOCK_REPORT_S:
+                        last_report = now
+                        print(
+                            f"Waited {now - start:.0f}s for another worker's "
+                            f"build of {shared_dir.name}"
+                        )
+                    await asyncio.sleep(_SHARED_LOCK_POLL_S)
+            # .built carries the ELF path of the last completed compile, so
+            # later workers skip the config re-read in _resolve_compiled_binary
+            stamp = shared_dir / ".built"
+            if (built := _shared_elf_paths.get(shared_dir)) is None:
+                built = await loop.run_in_executor(None, _read_stamp, stamp, shared_dir)
+            # Delete the ELF before compiling: whatever exists afterwards is
+            # this compile's output, so no staleness check is ever needed.
+            # With no usable stamp, sweep any leftover at the known layout
+            if built is not None:
+                built.unlink(missing_ok=True)
+            else:
+                # Layout-agnostic: ESPHOME_BUILD_PATH can move the build tree
+                for leftover in shared_dir.rglob("program"):
+                    if leftover.is_file():
+                        leftover.unlink()
+            await loop.run_in_executor(
+                None, write_file_if_changed, shared_config, content
+            )
+            await _run_esphome_compile(shared_config, shared_dir, env)
+            if built is None or not built.exists():
+                built = await loop.run_in_executor(
+                    None, _resolve_compiled_binary, shared_config
+                )
+            _shared_elf_paths[shared_dir] = built
+            await loop.run_in_executor(None, write_file, stamp, str(built))
+            # Copy out before unlocking: another worker may relink firmware.elf
+            # while this test is still running its private copy
+            await loop.run_in_executor(None, shutil.copy2, built, private_binary)
+        return private_binary
 
     yield _compile
 

tests/integration/const.py

@@ -9,6 +9,13 @@ API_CONNECTION_TIMEOUT = 30.0  # seconds
 PORT_WAIT_TIMEOUT = 30.0  # seconds
 PORT_POLL_INTERVAL = 0.1  # seconds
 
+# The well-known all-zeros provisioning PSK, a key to provision over it, and
+# the time the device takes to activate a newly saved key (100 ms timer plus
+# margin)
+ZERO_PSK = "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA="
+PROVISIONING_PSK = b"bm5ubm5ubm5ubm5ubm5ubm5ubm5ubm5ubm5ubm5ubm4="
+KEY_ACTIVATION_DELAY = 0.5  # seconds
+
 # Process shutdown timeouts
 SIGINT_TIMEOUT = 5.0  # seconds
 SIGTERM_TIMEOUT = 2.0  # seconds

tests/integration/fixtures/host_ota_api_key_offer_with_password.yaml

@@ -0,0 +1,12 @@
+esphome:
+  name: host-ota-test
+host:
+api:
+  encryption:
+    key: "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8="
+ota:
+  - platform: esphome
+    port: __OTA_PORT__
+    password: "hunter2"
+logger:
+  level: DEBUG

tests/integration/fixtures/host_ota_provisioned_api_key.yaml

@@ -0,0 +1,10 @@
+esphome:
+  name: host-ota-test
+host:
+api:
+  encryption:
+ota:
+  - platform: esphome
+    port: __OTA_PORT__
+logger:
+  level: DEBUG

tests/integration/fixtures/lvgl_headless_render.yaml

@@ -0,0 +1,53 @@
+esphome:
+  name: lvgl-headless-render-test
+host:
+
+api:
+  actions:
+    # The name comes from the test so it can capture more than once: a snapshot never writes over
+    # a file that is already there, so a fixed name could only ever be captured once.
+    - action: take_screenshot
+      variables:
+        name: string
+      then:
+        - snapshot.take:
+            id: lvgl_display
+            filename: !lambda return name;
+
+logger:
+  level: DEBUG
+
+display:
+  # A display with no screen, so what LVGL draws depends on LVGL alone - nothing about the machine
+  # running the test, and no graphics library outside this repository, can move the result.
+  - platform: snapshot
+    id: lvgl_display
+    auto_clear_enabled: false
+    dimensions:
+      width: 300
+      height: 300
+
+# The widgets are spelled out here rather than left to the built in "Hello World" screen, which
+# LVGL builds when nothing is configured: that screen contains a spinner, and an animation cannot
+# produce the same picture twice.
+#
+# Everything that affects the rendered pixels is set explicitly, so the expected hash in the test
+# depends only on the drawing code and the built in font. In particular the background comes from a
+# full screen object rather than from the theme, so adjusting a theme default does not break this.
+lvgl:
+  displays: lvgl_display
+  default_font: montserrat_14
+  widgets:
+    - obj:
+        width: 100%
+        height: 100%
+        bg_color: 0x000080
+        bg_opa: cover
+        border_width: 0
+        radius: 0
+        pad_all: 0
+        widgets:
+          - label:
+              align: center
+              text: "Hello World!"
+              text_color: 0xFFFFFF

tests/integration/fixtures/sdl_headless_screenshot.yaml

@@ -0,0 +1,29 @@
+esphome:
+  name: sdl-headless-screenshot-test
+host:
+
+api:
+  actions:
+    # The name comes from the test so it can capture more than once while it waits for the first
+    # frame: a snapshot never writes over a file that is already there.
+    - action: take_screenshot
+      variables:
+        name: string
+      then:
+        - snapshot.take:
+            id: sdl_display
+            filename: !lambda return name;
+
+logger:
+  level: DEBUG
+
+display:
+  - platform: sdl
+    id: sdl_display
+    headless: true
+    show_test_card: true
+    update_interval: 100ms
+    # An odd width exercises the row padding in the BMP writer
+    dimensions:
+      width: 101
+      height: 64

tests/integration/fixtures/sensor_filters_batch_window.yaml

@@ -1,58 +0,0 @@
-esphome:
-  name: test-batch-window-filters
-
-host:
-api:
-  batch_delay: 0ms  # Disable batching to receive all state updates
-logger:
-  level: DEBUG
-
-# Template sensor that we'll use to publish values
-sensor:
-  - platform: template
-    name: "Source Sensor"
-    id: source_sensor
-    accuracy_decimals: 2
-
-  # Batch window filters (window_size == send_every) - use streaming filters
-  - platform: copy
-    source_id: source_sensor
-    name: "Min Sensor"
-    id: min_sensor
-    filters:
-      - min:
-          window_size: 5
-          send_every: 5
-          send_first_at: 1
-
-  - platform: copy
-    source_id: source_sensor
-    name: "Max Sensor"
-    id: max_sensor
-    filters:
-      - max:
-          window_size: 5
-          send_every: 5
-          send_first_at: 1
-
-  - platform: copy
-    source_id: source_sensor
-    name: "Moving Avg Sensor"
-    id: moving_avg_sensor
-    filters:
-      - sliding_window_moving_average:
-          window_size: 5
-          send_every: 5
-          send_first_at: 1
-
-# Button to trigger publishing test values
-button:
-  - platform: template
-    name: "Publish Values Button"
-    id: publish_button
-    on_press:
-      - lambda: |-
-          // Publish 10 values: 1.0, 2.0, ..., 10.0
-          for (int i = 1; i <= 10; i++) {
-            id(source_sensor).publish_state(float(i));
-          }

tests/integration/fixtures/snapshot_display.yaml

@@ -0,0 +1,28 @@
+esphome:
+  name: snapshot-display-test
+host:
+
+api:
+  actions:
+    # The name comes from the test so it can ask for several in a row and check what each one
+    # does with it.
+    - action: take_snapshot
+      variables:
+        name: string
+      then:
+        - snapshot.take:
+            id: snapshot_display
+            filename: !lambda return name;
+
+logger:
+  level: DEBUG
+
+display:
+  - platform: snapshot
+    id: snapshot_display
+    show_test_card: true
+    update_interval: 100ms
+    # An odd width exercises the row padding in the BMP writer
+    dimensions:
+      width: 101
+      height: 64

tests/integration/fixtures/template_climate_basic.yaml

@@ -0,0 +1,72 @@
+esphome:
+  name: tmpl-clim-basic
+  on_boot:
+    - climate.template.publish:
+        id: test_climate
+        action: IDLE
+host:
+api:
+logger:
+
+climate:
+  - platform: template
+    id: test_climate
+    name: Test Basic Climate
+    optimistic: true
+    sensor: test_climate_current_temperature
+    humidity_sensor: test_climate_current_humidity
+    supports_action: true
+    supported_modes:
+      - "OFF"
+      - HEAT
+      - COOL
+    supported_fan_modes:
+      - AUTO
+      - LOW
+      - HIGH
+    supported_swing_modes:
+      - "OFF"
+      - VERTICAL
+    supported_presets:
+      - NONE
+      - ECO
+    visual:
+      min_temperature: 16.0
+      max_temperature: 30.0
+      temperature_step: 0.5
+    on_control:
+      - lambda: |-
+          if (x.get_mode().has_value())
+            ESP_LOGD("test", "on_control mode=%d", (int) *x.get_mode());
+          if (x.get_target_temperature().has_value())
+            ESP_LOGD("test", "on_control target_temperature=%.1f", *x.get_target_temperature());
+          if (x.get_fan_mode().has_value())
+            ESP_LOGD("test", "on_control fan_mode=%d", (int) *x.get_fan_mode());
+          if (x.get_swing_mode().has_value())
+            ESP_LOGD("test", "on_control swing_mode=%d", (int) *x.get_swing_mode());
+          if (x.get_preset().has_value())
+            ESP_LOGD("test", "on_control preset=%d", (int) *x.get_preset());
+
+sensor:
+  - platform: template
+    id: test_climate_current_temperature
+    name: Test Climate Current Temperature
+    lambda: "return 22.5f;"
+    update_interval: 10ms
+  - platform: template
+    id: test_climate_current_humidity
+    name: Test Climate Current Humidity
+    lambda: "return 55.0f;"
+    update_interval: 10ms
+
+button:
+  - platform: template
+    id: simulate_device_report
+    name: Simulate Device Report
+    on_press:
+      - climate.template.publish:
+          id: test_climate
+          mode: "OFF"
+          fan_mode: AUTO
+          swing_mode: "OFF"
+          preset: NONE

tests/integration/fixtures/template_climate_custom_modes.yaml

@@ -0,0 +1,47 @@
+esphome:
+  name: tmpl-clim-custom
+host:
+api:
+logger:
+
+climate:
+  - platform: template
+    id: test_climate
+    name: Test Custom Mode Climate
+    optimistic: true
+    sensor: test_climate_current_temperature
+    supported_modes:
+      - "OFF"
+      - HEAT
+      - COOL
+    custom_fan_modes:
+      - turbo
+      - silent
+      - eco
+    custom_presets:
+      - eco_plus
+      - power_save
+      - max
+    on_control:
+      - lambda: |-
+          if (x.has_custom_fan_mode())
+            ESP_LOGD("test", "on_control custom_fan_mode=%s", x.get_custom_fan_mode().c_str());
+          if (x.has_custom_preset())
+            ESP_LOGD("test", "on_control custom_preset=%s", x.get_custom_preset().c_str());
+
+sensor:
+  - platform: template
+    id: test_climate_current_temperature
+    name: Test Climate Current Temperature
+    lambda: "return 22.5f;"
+    update_interval: 10ms
+
+button:
+  - platform: template
+    id: simulate_device_report
+    name: Simulate Device Report
+    on_press:
+      - climate.template.publish:
+          id: test_climate
+          custom_fan_mode: "eco"
+          custom_preset: "max"

tests/integration/fixtures/template_climate_nonoptimistic.yaml

@@ -0,0 +1,56 @@
+esphome:
+  name: tmpl-clim-nonopt
+host:
+api:
+logger:
+
+climate:
+  - platform: template
+    id: test_climate
+    name: Test Template Climate Nonoptimistic
+    optimistic: false
+    supported_modes:
+      - "OFF"
+      - HEAT
+      - COOL
+      - FAN_ONLY
+    supported_fan_modes:
+      - AUTO
+      - LOW
+      - HIGH
+    supported_swing_modes:
+      - "OFF"
+      - VERTICAL
+    supported_presets:
+      - NONE
+      - ECO
+      - AWAY
+    visual:
+      min_temperature: 16.0
+      max_temperature: 30.0
+      temperature_step: 0.5
+    on_control:
+      - lambda: |-
+          if (x.get_mode().has_value())
+            ESP_LOGD("test", "on_control mode=%d", (int) *x.get_mode());
+          if (x.get_target_temperature().has_value())
+            ESP_LOGD("test", "on_control target_temperature=%.1f", *x.get_target_temperature());
+          if (x.get_fan_mode().has_value())
+            ESP_LOGD("test", "on_control fan_mode=%d", (int) *x.get_fan_mode());
+          if (x.get_swing_mode().has_value())
+            ESP_LOGD("test", "on_control swing_mode=%d", (int) *x.get_swing_mode());
+          if (x.get_preset().has_value())
+            ESP_LOGD("test", "on_control preset=%d", (int) *x.get_preset());
+
+button:
+  - platform: template
+    id: simulate_device_confirmation
+    name: Simulate Device Confirmation
+    on_press:
+      - climate.template.publish:
+          id: test_climate
+          mode: HEAT
+          target_temperature: 22.5
+          fan_mode: HIGH
+          swing_mode: VERTICAL
+          preset: AWAY

tests/integration/fixtures/template_climate_on_control_ordering.yaml

@@ -0,0 +1,26 @@
+esphome:
+  name: tmpl-clim-oc-order
+host:
+api:
+logger:
+
+# on_control fires with the full ClimateCall (arg `x`) from the base Climate component's
+# ClimateCall::perform(), before validate_()/control() run -- so when the lambda action below
+# runs, the entity's own .mode is still the OLD value, even though x.get_mode() already reports
+# the NEW requested value. on_state fires afterward, once control() has applied it.
+climate:
+  - platform: template
+    id: test_climate
+    name: Test On Control Ordering
+    optimistic: true
+    supported_modes:
+      - "OFF"
+      - HEAT
+    on_control:
+      - lambda: |-
+          ESP_LOGD("test", "on_control requested_mode=%d current_mode_before_apply=%d",
+                   x.get_mode().has_value() ? (int) *x.get_mode() : -1,
+                   (int) id(test_climate).mode);
+    on_state:
+      - lambda: |-
+          ESP_LOGD("test", "on_state mode=%d", (int) x.mode);

tests/integration/fixtures/template_climate_publish_all_fields.yaml

@@ -0,0 +1,63 @@
+esphome:
+  name: tmpl-clim-publish-all
+host:
+api:
+logger:
+
+climate:
+  - platform: template
+    id: test_climate
+    name: Test Publish All Fields
+    optimistic: true
+    # current_temperature/current_humidity/action are only sent over the API at all if their
+    # trait is advertised: current_temperature/current_humidity because a sensor/humidity_sensor
+    # is referenced below, action because supports_action is set. The sensors' fixed readings
+    # match what climate.template.publish pushes, so the sensor callback (guarded to only publish
+    # on an actual change) doesn't produce an extra, unexpected state update of its own.
+    sensor: test_climate_current_temperature
+    humidity_sensor: test_climate_current_humidity
+    supports_action: true
+    supported_modes:
+      - "OFF"
+      - HEAT
+    supported_fan_modes:
+      - AUTO
+      - HIGH
+    supported_swing_modes:
+      - "OFF"
+      - VERTICAL
+    supported_presets:
+      - NONE
+      - ECO
+    on_control:
+      # Should never fire in this test: climate.template.publish is a pure bypass and must not
+      # re-trigger on_control as if the entity were freshly commanded.
+      - logger.log: "on_control fired"
+
+sensor:
+  - platform: template
+    id: test_climate_current_temperature
+    name: Test Climate Current Temperature
+    lambda: "return 20.0f;"
+    update_interval: 10ms
+  - platform: template
+    id: test_climate_current_humidity
+    name: Test Climate Current Humidity
+    lambda: "return 60.0f;"
+    update_interval: 10ms
+
+button:
+  - platform: template
+    id: publish_all
+    name: Publish All
+    on_press:
+      - climate.template.publish:
+          id: test_climate
+          current_temperature: 20.0
+          current_humidity: 60.0
+          target_temperature: 23.0
+          mode: HEAT
+          action: HEATING
+          fan_mode: HIGH
+          swing_mode: VERTICAL
+          preset: ECO

tests/integration/fixtures/template_climate_sensor_push.yaml

@@ -0,0 +1,49 @@
+esphome:
+  name: tmpl-clim-sensor-push
+host:
+api:
+logger:
+
+# No lambda/update_interval: these sensors only ever report a value when a button below
+# publishes one (standing in for e.g. a BLE scan callback in a real config).
+sensor:
+  - platform: template
+    id: room_temperature
+    name: Room Temperature
+  - platform: template
+    id: room_humidity
+    name: Room Humidity
+
+climate:
+  - platform: template
+    id: test_climate
+    name: Test Sensor Push Climate
+    optimistic: true
+    sensor: room_temperature
+    humidity_sensor: room_humidity
+    supported_modes:
+      - "OFF"
+      - HEAT
+
+button:
+  - platform: template
+    id: publish_temperature
+    name: Publish Temperature
+    on_press:
+      - sensor.template.publish:
+          id: room_temperature
+          state: 24.0
+  - platform: template
+    id: publish_temperature_same
+    name: Publish Temperature Same Value
+    on_press:
+      - sensor.template.publish:
+          id: room_temperature
+          state: 24.0
+  - platform: template
+    id: publish_humidity
+    name: Publish Humidity
+    on_press:
+      - sensor.template.publish:
+          id: room_humidity
+          state: 65.0

tests/integration/fixtures/template_climate_set_actions.yaml

@@ -0,0 +1,89 @@
+esphome:
+  name: tmpl-clim-set-act
+host:
+api:
+logger:
+
+# Every settable field forwards its requested value to a set_*_action. supports_two_point and
+# supports_target_humidity are not declared here: they are derived from the low/high and humidity
+# set actions being present.
+climate:
+  - platform: template
+    id: test_climate
+    name: Test Set Actions
+    optimistic: false
+    restore_mode: NO_RESTORE
+    supported_modes:
+      - "OFF"
+      - HEAT
+      - COOL
+    supported_fan_modes:
+      - AUTO
+      - LOW
+    supported_swing_modes:
+      - "OFF"
+      - VERTICAL
+    supported_presets:
+      - NONE
+      - ECO
+    custom_fan_modes:
+      - turbo
+    custom_presets:
+      - eco_plus
+    visual:
+      min_temperature: 16.0
+      max_temperature: 30.0
+      temperature_step: 0.5
+    set_mode_action:
+      - logger.log:
+          format: "set_mode_action %d"
+          args: ["(int) x"]
+    set_target_temperature_low_action:
+      - logger.log:
+          format: "set_target_temperature_low_action %.1f"
+          args: ["x"]
+    set_target_temperature_high_action:
+      - logger.log:
+          format: "set_target_temperature_high_action %.1f"
+          args: ["x"]
+    set_target_humidity_action:
+      - logger.log:
+          format: "set_target_humidity_action %.0f"
+          args: ["x"]
+    set_fan_mode_action:
+      - logger.log:
+          format: "set_fan_mode_action %d"
+          args: ["(int) x"]
+    set_custom_fan_mode_action:
+      - logger.log:
+          format: "set_custom_fan_mode_action %s"
+          args: ["x.c_str()"]
+    set_swing_mode_action:
+      - logger.log:
+          format: "set_swing_mode_action %d"
+          args: ["(int) x"]
+    set_preset_action:
+      - logger.log:
+          format: "set_preset_action %d"
+          args: ["(int) x"]
+    set_custom_preset_action:
+      - logger.log:
+          format: "set_custom_preset_action %s"
+          args: ["x.c_str()"]
+
+button:
+  - platform: template
+    id: report_device_state
+    name: Report Device State
+    on_press:
+      - climate.template.publish:
+          id: test_climate
+          mode: HEAT
+
+  - platform: template
+    id: report_unsupported_mode
+    name: Report Unsupported Mode
+    on_press:
+      - climate.template.publish:
+          id: test_climate
+          mode: DRY

tests/integration/fixtures/template_climate_two_point_temperature.yaml

@@ -0,0 +1,52 @@
+esphome:
+  name: tmpl-clim-two-point
+host:
+api:
+logger:
+
+climate:
+  - platform: template
+    id: test_climate
+    name: Test Two-Point Heatpump
+    optimistic: true
+    sensor: test_climate_current_temperature
+    supports_two_point_target_temperature: true
+    supports_target_humidity: true
+    supported_modes:
+      - "OFF"
+      - HEAT_COOL
+      - HEAT
+      - COOL
+    visual:
+      min_temperature: 16.0
+      max_temperature: 30.0
+      temperature_step: 0.5
+    on_control:
+      - lambda: |-
+          if (x.get_mode().has_value())
+            ESP_LOGD("test", "on_control mode=%d", (int) *x.get_mode());
+          if (x.get_target_temperature_low().has_value())
+            ESP_LOGD("test", "on_control target_temperature_low=%.1f", *x.get_target_temperature_low());
+          if (x.get_target_temperature_high().has_value())
+            ESP_LOGD("test", "on_control target_temperature_high=%.1f", *x.get_target_temperature_high());
+          if (x.get_target_humidity().has_value())
+            ESP_LOGD("test", "on_control target_humidity=%.1f", *x.get_target_humidity());
+
+sensor:
+  - platform: template
+    id: test_climate_current_temperature
+    name: Test Climate Current Temperature
+    lambda: "return 21.0f;"
+    update_interval: 10ms
+
+button:
+  - platform: template
+    id: simulate_device_report
+    name: Simulate Device Report
+    on_press:
+      - climate.template.publish:
+          id: test_climate
+          mode: HEAT_COOL
+          target_temperature_low: 18.0
+          target_temperature_high: 24.0
+          target_humidity: 50.0

tests/integration/fixtures/uart_mock_modbus_client_read_write.yaml

@@ -1,111 +0,0 @@
-esphome:
-  name: uart-mock-modbus-cli-rw
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-# Two virtual buses looped back to each other: the client's transmissions reach the server and the
-# server's replies reach the client. auto_start so forwarding is active before the button fires.
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_client
-              data: !lambda return data;
-  - id: virtual_uart_client
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-globals:
-  - id: stored_1
-    type: uint16_t
-    initial_value: "0"
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_client
-    id: virtual_modbus_client
-    role: client
-    turnaround_time: 10ms
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    registers:
-      # Writable + readable register: the read publishes what it returns, so the test can confirm the
-      # write half of the 0x17 ran before the read half (Modbus 6.17).
-      - address: 0x01
-        value_type: U_WORD
-        read_lambda: |-
-          id(srv_read_1).publish_state(id(stored_1));
-          return id(stored_1);
-        write_lambda: |-
-          id(stored_1) = x;
-          id(srv_write_1).publish_state(x);
-          return true;
-      # Read-only register, returned together with 0x01 by the 2-register read half.
-      - address: 0x02
-        value_type: U_WORD
-        read_lambda: return 0x00AA;
-
-sensor:
-  # Server-side observations.
-  - platform: template
-    name: "srv_write_1"
-    id: srv_write_1
-  - platform: template
-    name: "srv_read_1"
-    id: srv_read_1
-  # Client-side read-back: the values the client's on_response received.
-  - platform: template
-    name: "client_read_0"
-    id: client_read_0
-  - platform: template
-    name: "client_read_1"
-    id: client_read_1
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    on_press:
-      # FC 0x17: write reg 0x0001 = 0x1234, then read regs 0x0001..0x0002 back in the same transaction.
-      - modbus_client.read_write_multiple_registers:
-          address: 0x01
-          read_address: 0x0001
-          read_count: 2
-          write_address: 0x0001
-          values: [0x1234]
-          on_response:
-            then:
-              - lambda: |-
-                  // values is the read-back block: reg 0x0001 (must be the just-written 0x1234) and reg 0x0002.
-                  if (values.size() >= 2) {
-                    id(client_read_0).publish_state(values[0]);
-                    id(client_read_1).publish_state(values[1]);
-                  }

tests/integration/fixtures/uart_mock_modbus_custom_pdu.yaml

@@ -1,88 +0,0 @@
-esphome:
-  name: uart-mock-modbus-custom-pdu
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_controller
-    id: modbus_controller_1
-    update_interval: 1s
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    id: modbus_server_1
-    registers:
-      - address: 0x01
-        value_type: U_WORD
-        read_lambda: return 259;
-
-sensor:
-  # Plain read to confirm the controller <-> server link is up.
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "plain_read"
-    address: 0x01
-    register_type: holding
-    value_type: U_WORD
-  # Custom PDU: read holding register 0x0001, count 1. The PDU is
-  # {function code, address hi, address lo, count hi, count lo}; the device
-  # address and CRC are added by the hub. The lambda parses the response payload
-  # (the register value, big-endian).
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "custom_read"
-    custom_pdu: [0x03, 0x00, 0x01, 0x00, 0x01]
-    lambda: |-
-      if (data.size() < 2) return {};
-      return (float) ((data[0] << 8) | data[1]);
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)

tests/integration/fixtures/uart_mock_modbus_deprecated_write_buffer.yaml

@@ -1,106 +0,0 @@
-esphome:
-  name: uart-mock-modbus-dep-buffer
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-globals:
-  - id: reg10
-    type: uint16_t
-    initial_value: "0"
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_controller
-    id: modbus_controller_1
-    update_interval: 1s
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    id: modbus_server_1
-    registers:
-      - address: 0x10
-        value_type: U_WORD
-        read_lambda: return id(reg10);
-        write_lambda: |-
-          id(reg10) = x;
-          return true;
-
-# A number whose write_lambda uses the DEPRECATED buffer parameter (fills `payload` with a legacy raw
-# frame as words: device address + function code + data) instead of the new item->write_* API. The write
-# must still land with its legacy semantics, and the one-time deprecation warning must fire only once per
-# entity no matter how many writes happen.
-number:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "buf_number"
-    id: buf_number
-    address: 0x10
-    register_type: holding
-    value_type: U_WORD
-    min_value: 0
-    max_value: 1000
-    step: 1
-    write_lambda: |-
-      // Legacy raw frame as words: [addr 0x01 | fc 0x06], register 0x0010, value.
-      payload.push_back(0x0106);
-      payload.push_back(0x0010);
-      payload.push_back((uint16_t) x);
-      return {};
-
-# Reports the server-side register so the test can observe that the deprecated buffer write landed.
-sensor:
-  - platform: template
-    name: "written_value"
-    id: written_value
-    update_interval: 0.5s
-    lambda: "return id(reg10);"
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # The test drives the writes via number_command; the mock is autostart.

tests/integration/fixtures/uart_mock_modbus_lambda_invert.yaml

@@ -1,95 +0,0 @@
-esphome:
-  name: uart-mock-modbus-lambda-invert
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-globals:
-  - id: reg40
-    type: uint16_t
-    initial_value: "5"
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_controller
-    id: modbus_controller_1
-    update_interval: 1s
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    id: modbus_server_1
-    registers:
-      - address: 0x40
-        value_type: U_WORD
-        read_lambda: return id(reg40);
-        write_lambda: id(reg40) = x; return true;
-
-# An active-low holding switch: the write_lambda inverts the wire value, but the entity must still
-# report the REQUESTED state. assumed_state keeps the register unpolled, so the published state comes
-# only from write_state() - turning ON writes 0x0000 yet the switch shows ON.
-switch:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "invert_switch"
-    register_type: holding
-    address: 0x40
-    assumed_state: true
-    write_lambda: |-
-      return !x;
-
-sensor:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_40"
-    address: 0x40
-    register_type: holding
-    value_type: U_WORD
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)

tests/integration/fixtures/uart_mock_modbus_lambda_write.yaml

@@ -1,97 +0,0 @@
-esphome:
-  name: uart-mock-modbus-lambda-write
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-globals:
-  - id: reg30
-    type: uint16_t
-    initial_value: "0"
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_controller
-    id: modbus_controller_1
-    update_interval: 1s
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    id: modbus_server_1
-    registers:
-      - address: 0x30
-        value_type: U_WORD
-        read_lambda: return id(reg30);
-        write_lambda: id(reg30) = x; return true;
-
-# A COIL-type switch (assumed_state, write-only) whose write_lambda ignores its own coil type and instead
-# drives a HOLDING-REGISTER write on the mock server through the entity itself: `item` IS the command, so
-# item->write_single_register() sends a register write from a coil entity (cross-type). Returning nothing
-# (an empty optional) tells the write path the lambda already dispatched the frame - no default coil write.
-switch:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "cross_switch"
-    register_type: coil
-    address: 0x00
-    assumed_state: true
-    write_lambda: |-
-      item->write_single_register(0x30, x ? 1234 : 0);
-      return {};
-
-sensor:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_30"
-    address: 0x30
-    register_type: holding
-    value_type: U_WORD
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)

tests/integration/fixtures/uart_mock_modbus_loopback.yaml

@@ -0,0 +1,233 @@
+esphome:
+  name: uart-mock-modbus-loopback
+
+host:
+api:
+logger:
+  level: VERBOSE
+
+external_components:
+  - source:
+      type: local
+      path: EXTERNAL_COMPONENT_PATH
+
+# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
+# The actual UART bus used is the uart_mock component below
+uart:
+  baud_rate: 115200
+  port: /dev/null
+
+# Shared loopback fixture (see the shared_yaml markers in the test file);
+# register spaces are disjoint so each test only observes its own entities.
+uart_mock:
+  - id: virtual_uart_server
+    baud_rate: 9600
+    auto_start: true
+    debug:
+    on_tx:
+      - then:
+          - uart_mock.inject_rx:
+              id: virtual_uart_controller
+              data: !lambda return data;
+  - id: virtual_uart_controller
+    baud_rate: 9600
+    auto_start: true
+    debug:
+    on_tx:
+      - then:
+          - uart_mock.inject_rx:
+              id: virtual_uart_server
+              data: !lambda return data;
+
+globals:
+  - id: reg10
+    type: uint16_t
+    initial_value: "100"
+  - id: reg11
+    type: uint16_t
+    initial_value: "200"
+  - id: reg12
+    type: uint16_t
+    initial_value: "300"
+  - id: reg13
+    type: uint16_t
+    initial_value: "0xABCD"
+  - id: reg30
+    type: uint16_t
+    initial_value: "0"
+  - id: reg40
+    type: uint16_t
+    initial_value: "5"
+  - id: reg50
+    type: uint16_t
+    initial_value: "0"
+
+modbus:
+  - uart_id: virtual_uart_server
+    id: virtual_modbus_server
+    role: server
+  - uart_id: virtual_uart_controller
+    id: virtual_modbus_controller
+    role: client
+    turnaround_time: 10ms
+
+modbus_controller:
+  - address: 1
+    modbus_id: virtual_modbus_controller
+    id: modbus_controller_1
+    update_interval: 1s
+
+modbus_server:
+  - address: 1
+    modbus_id: virtual_modbus_server
+    registers:
+      - address: 0x01
+        value_type: U_WORD
+        read_lambda: return 259;
+      - address: 0x10
+        value_type: U_WORD
+        read_lambda: return id(reg10);
+        write_lambda: id(reg10) = x; return true;
+      - address: 0x11
+        value_type: U_WORD
+        read_lambda: return id(reg11);
+        write_lambda: id(reg11) = x; return true;
+      - address: 0x12
+        value_type: U_WORD
+        read_lambda: return id(reg12);
+        write_lambda: id(reg12) = x; return true;
+      - address: 0x13
+        value_type: U_WORD
+        read_lambda: return id(reg13);
+      - address: 0x30
+        value_type: U_WORD
+        read_lambda: return id(reg30);
+        write_lambda: id(reg30) = x; return true;
+      - address: 0x40
+        value_type: U_WORD
+        read_lambda: return id(reg40);
+        write_lambda: id(reg40) = x; return true;
+      - address: 0x50
+        value_type: U_WORD
+        read_lambda: return id(reg50);
+        write_lambda: id(reg50) = x; return true;
+
+# Byte-based offset: 2 bytes -> register 0x11 (the old code folded it in as a
+# register count, hitting 0x12). assumed_state keeps the switch write-only.
+switch:
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "offset_switch"
+    register_type: holding
+    address: 0x10
+    offset: 2
+    assumed_state: true
+  # Reading switch, byte offset 6 -> register 0x13; the pre-fix resolution (0x16)
+  # would draw ILLEGAL_DATA_ADDRESS and never publish.
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "read_offset_switch"
+    register_type: holding
+    address: 0x10
+    offset: 6
+    bitmask: 0x1
+  # Coil switch whose write_lambda dispatches a holding-register write via `item`;
+  # returning an empty optional suppresses the default coil write.
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "cross_switch"
+    register_type: coil
+    address: 0x00
+    assumed_state: true
+    write_lambda: |-
+      item->write_single_register(0x30, x ? 1234 : 0);
+      return {};
+  # Active-low: the write_lambda inverts the wire value but the entity must still
+  # report the requested state (assumed_state keeps the register unpolled).
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "invert_switch"
+    register_type: holding
+    address: 0x40
+    assumed_state: true
+    write_lambda: |-
+      return !x;
+
+# Uses the deprecated buffer parameter (legacy raw frame as words); the write
+# must land and the deprecation warning must fire only once per entity.
+number:
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "buf_number"
+    id: buf_number
+    address: 0x50
+    register_type: holding
+    value_type: U_WORD
+    min_value: 0
+    max_value: 1000
+    step: 1
+    write_lambda: |-
+      // Legacy raw frame as words: [addr 0x01 | fc 0x06], register 0x0050, value.
+      payload.push_back(0x0106);
+      payload.push_back(0x0050);
+      payload.push_back((uint16_t) x);
+      return {};
+
+sensor:
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "plain_read"
+    address: 0x01
+    register_type: holding
+    value_type: U_WORD
+  # Custom PDU: read holding register 0x0001; device address and CRC are added
+  # by the hub. The lambda parses the big-endian register value.
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "custom_read"
+    custom_pdu: [0x03, 0x00, 0x01, 0x00, 0x01]
+    lambda: |-
+      if (data.size() < 2) return {};
+      return (float) ((data[0] << 8) | data[1]);
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "reg_10"
+    address: 0x10
+    register_type: holding
+    value_type: U_WORD
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "reg_11"
+    address: 0x11
+    register_type: holding
+    value_type: U_WORD
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "reg_12"
+    address: 0x12
+    register_type: holding
+    value_type: U_WORD
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "reg_30"
+    address: 0x30
+    register_type: holding
+    value_type: U_WORD
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "reg_40"
+    address: 0x40
+    register_type: holding
+    value_type: U_WORD
+  # Reports the server-side register so the test can observe that the deprecated buffer write landed.
+  - platform: template
+    name: "written_value"
+    id: written_value
+    update_interval: 0.5s
+    lambda: "return id(reg50);"
+
+button:
+  - platform: template
+    name: "Start Scenario"
+    id: start_scenario_btn
+    # Nothing to start (mock is autostart); tests drive entities directly

tests/integration/fixtures/uart_mock_modbus_mesh.yaml

@@ -1,5 +1,5 @@
 esphome:
-  name: uart-mock-modbus-server-contro
+  name: uart-mock-modbus-mesh
 
 host:
 api:
@@ -17,13 +17,14 @@ uart:
   baud_rate: 115200
   port: /dev/null
 
+# Shared 3-bus mesh (see the shared_yaml markers): addr 1 = typed read-only
+# registers, addr 5 = the read/write 0x17 target, addr 2/3 on the second
+# server hub. auto_start everywhere: the controller polls at boot, so the
+# forwarding must already be live or early requests generate warnings.
+# Every test presses Start Scenario, so all merged actions fire in every test.
 uart_mock:
   - id: virtual_uart_server
     baud_rate: 9600
-    # auto_start must be true for loopback fixtures: the modbus controller
-    # polls on its update_interval immediately at boot, so the uart_mock
-    # forwarding must already be active or early requests are lost and
-    # generate modbus warnings.
     auto_start: true
     debug:
     on_tx:
@@ -31,35 +32,68 @@ uart_mock:
           - uart_mock.inject_rx:
               id: virtual_uart_controller
               data: !lambda return data;
-  - id: virtual_uart_controller
+          - uart_mock.inject_rx:
+              id: virtual_uart_server_2
+              data: !lambda return data;
+  - id: virtual_uart_server_2
     baud_rate: 9600
-    auto_start: true # See comment on virtual_uart_server above
+    auto_start: true
     debug:
     on_tx:
       - then:
           - uart_mock.inject_rx:
               id: virtual_uart_server
               data: !lambda return data;
+          - uart_mock.inject_rx:
+              id: virtual_uart_controller
+              data: !lambda return data;
+  - id: virtual_uart_controller
+    baud_rate: 9600
+    auto_start: true
+    debug:
+    on_tx:
+      - then:
+          - uart_mock.inject_rx:
+              id: virtual_uart_server
+              data: !lambda return data;
+          - uart_mock.inject_rx:
+              id: virtual_uart_server_2
+              data: !lambda return data;
+
+globals:
+  - id: stored_1
+    type: uint16_t
+    initial_value: "0"
 
 modbus:
   - uart_id: virtual_uart_server
     id: virtual_modbus_server
     role: server
+  - uart_id: virtual_uart_server_2
+    id: virtual_modbus_server_2
+    role: server
   - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
+    id: virtual_modbus_client
     role: client
     turnaround_time: 10ms
 
 modbus_controller:
   - address: 1
-    modbus_id: virtual_modbus_controller
+    modbus_id: virtual_modbus_client
     id: modbus_controller_1
     update_interval: 1s
+  - address: 2
+    modbus_id: virtual_modbus_client
+    id: modbus_controller_2
+    update_interval: 1s
+  - address: 3
+    modbus_id: virtual_modbus_client
+    id: modbus_controller_3
+    update_interval: 1s
 
 modbus_server:
   - address: 1
     modbus_id: virtual_modbus_server
-    id: modbus_server_1
     registers:
       - address: 0x01
         value_type: U_WORD
@@ -103,6 +137,34 @@ modbus_server:
       - address: 0x28
         value_type: FP32_R
         read_lambda: return 3.14;
+  - address: 5
+    modbus_id: virtual_modbus_server
+    registers:
+      # Writable + readable register: srv_write_1 plus the client's read-back
+      # confirm the write half of the 0x17 ran before the read half (Modbus 6.17).
+      - address: 0x01
+        value_type: U_WORD
+        read_lambda: return id(stored_1);
+        write_lambda: |-
+          id(stored_1) = x;
+          id(srv_write_1).publish_state(x);
+          return true;
+      # Read-only register, returned together with 0x01 by the 2-register read half.
+      - address: 0x02
+        value_type: U_WORD
+        read_lambda: return 0x00AA;
+  - address: 2
+    modbus_id: virtual_modbus_server_2
+    registers:
+      - address: 0x01
+        value_type: U_WORD
+        read_lambda: return 919;
+  - address: 3
+    modbus_id: virtual_modbus_server_2
+    registers:
+      - address: 0x01
+        value_type: U_WORD
+        read_lambda: return 929;
 
 sensor:
   - platform: modbus_controller
@@ -195,9 +257,46 @@ sensor:
     address: 0x28
     register_type: holding
     value_type: FP32_R
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_2
+    name: "multi_reg_a"
+    address: 0x01
+    register_type: holding
+    value_type: U_WORD
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_3
+    name: "multi_reg_b"
+    address: 0x01
+    register_type: holding
+    value_type: U_WORD
+  # client_read_write observations, server- and client-side.
+  - platform: template
+    name: "srv_write_1"
+    id: srv_write_1
+  - platform: template
+    name: "client_read_0"
+    id: client_read_0
+  - platform: template
+    name: "client_read_1"
+    id: client_read_1
 
 button:
   - platform: template
     name: "Start Scenario"
     id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)
+    on_press:
+      # FC 0x17: write reg 0x0001 = 0x1234, then read regs 0x0001..0x0002 back in the same transaction.
+      - modbus_client.read_write_multiple_registers:
+          address: 5
+          read_address: 0x0001
+          read_count: 2
+          write_address: 0x0001
+          values: [0x1234]
+          on_response:
+            then:
+              - lambda: |-
+                  // values is the read-back block: reg 0x0001 (must be the just-written 0x1234) and reg 0x0002.
+                  if (values.size() >= 2) {
+                    id(client_read_0).publish_state(values[0]);
+                    id(client_read_1).publish_state(values[1]);
+                  }

tests/integration/fixtures/uart_mock_modbus_register_offset.yaml

@@ -1,138 +0,0 @@
-esphome:
-  name: uart-mock-modbus-reg-offset
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-globals:
-  - id: reg10
-    type: uint16_t
-    initial_value: "100"
-  - id: reg11
-    type: uint16_t
-    initial_value: "200"
-  - id: reg12
-    type: uint16_t
-    initial_value: "300"
-  - id: reg13
-    type: uint16_t
-    initial_value: "0xABCD"
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_controller
-    id: modbus_controller_1
-    update_interval: 1s
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    id: modbus_server_1
-    registers:
-      - address: 0x10
-        value_type: U_WORD
-        read_lambda: return id(reg10);
-        write_lambda: id(reg10) = x; return true;
-      - address: 0x11
-        value_type: U_WORD
-        read_lambda: return id(reg11);
-        write_lambda: id(reg11) = x; return true;
-      - address: 0x12
-        value_type: U_WORD
-        read_lambda: return id(reg12);
-        write_lambda: id(reg12) = x; return true;
-      - address: 0x13
-        value_type: U_WORD
-        read_lambda: return id(reg13);
-        write_lambda: id(reg13) = x; return true;
-
-# A holding-register switch at 0x10 with a 2-BYTE offset. offset is byte-based, so the write must target
-# register 0x10 + 2/2 = 0x11. The old (pre-fix) behavior folded offset into the address as a register
-# count, hitting 0x12 instead. assumed_state keeps the switch write-only so it does not read any register.
-switch:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "offset_switch"
-    register_type: holding
-    address: 0x10
-    offset: 2
-    assumed_state: true
-  # A holding-register switch that READS its state. Byte offset 6 -> register 0x10 + 6/2 = 0x13. Post-fix
-  # the switch itself resolves to 0x13 (the even byte offset folds into the address as whole registers) and
-  # joins the 0x10..0x13 range, so no separate 0x13 sensor is needed. Pre-fix the whole byte offset folds
-  # into the address (0x16), where the server answers ILLEGAL_DATA_ADDRESS and the switch never publishes.
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "read_offset_switch"
-    register_type: holding
-    address: 0x10
-    offset: 6
-    bitmask: 0x1
-
-sensor:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_10"
-    address: 0x10
-    register_type: holding
-    value_type: U_WORD
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_11"
-    address: 0x11
-    register_type: holding
-    value_type: U_WORD
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_12"
-    address: 0x12
-    register_type: holding
-    value_type: U_WORD
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)

tests/integration/fixtures/uart_mock_modbus_server.yaml

@@ -1,124 +0,0 @@
-esphome:
-  name: uart-mock-modbus-server-test
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_dev
-    baud_rate: 9600
-    rx_full_threshold: 120
-    rx_timeout: 2
-    auto_start: false
-    debug:
-    injections:
-      - delay: 100ms
-        inject_rx: [0x01, 0x03, 0x00, 0x03, 0x00, 0x01, 0x74, 0x0A] #  Read holding register 3 on device 1 (basic_read)
-      - delay: 100ms
-        #  Read holding register 7 on device 2
-        #  Reply from device 2
-        #  Read holding register 5 on device 1 (read_after_peer_response)
-        inject_rx:
-          [
-            0x02,
-            0x03,
-            0x00,
-            0x07,
-            0x00,
-            0x01,
-            0x35,
-            0xF8,
-            0x02,
-            0x03,
-            0x02,
-            0x00,
-            0xF0,
-            0xFC,
-            0x00,
-            0x01,
-            0x03,
-            0x00,
-            0x05,
-            0x00,
-            0x01,
-            0x94,
-            0x0B,
-          ]
-      - delay: 100ms
-        inject_rx: [0x02, 0x03, 0x00, 0x07, 0x00, 0x01, 0x35, 0xF8] #  Read holding register 7 on device 2, with no response
-      - delay: 100ms
-        #  Read holding register 7 on device 2, with no response
-        #  Read holding register A on device 1 (read_after_peer_timeout)
-        inject_rx:
-          [
-            0x02,
-            0x03,
-            0x00,
-            0x07,
-            0x00,
-            0x01,
-            0x35,
-            0xF8,
-            0x01,
-            0x03,
-            0x00,
-            0x0A,
-            0x00,
-            0x01,
-            0xA4,
-            0x08,
-          ]
-
-modbus:
-  uart_id: virtual_uart_dev
-  role: server
-
-modbus_server:
-  - address: 1
-    registers:
-      - address: 0x03
-        value_type: U_WORD
-        read_lambda: |-
-          id(basic_read).publish_state(1);
-          return 1;
-      - address: 0x05
-        value_type: U_WORD
-        read_lambda: |-
-          id(read_after_peer_response).publish_state(1);
-          return 1;
-      - address: 0x0A
-        value_type: U_WORD
-        read_lambda: |-
-          id(read_after_peer_timeout).publish_state(1);
-          return 1;
-
-sensor:
-  - platform: template
-    name: "basic_read"
-    id: basic_read
-  - platform: template
-    name: "read_after_peer_response"
-    id: read_after_peer_response
-  - platform: template
-    name: "read_after_peer_timeout"
-    id: read_after_peer_timeout
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    on_press:
-      - lambda: "id(virtual_uart_dev).start_scenario();"

tests/integration/fixtures/uart_mock_modbus_server_controller_multiple.yaml

@@ -1,116 +0,0 @@
-esphome:
-  name: uart-mock-modbus-server-mult
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    # auto_start must be true for loopback fixtures: the modbus controller
-    # polls on its update_interval immediately at boot, so the uart_mock
-    # forwarding must already be active or early requests are lost and
-    # generate modbus warnings.
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-          - uart_mock.inject_rx:
-              id: virtual_uart_server_2
-              data: !lambda return data;
-  - id: virtual_uart_server_2
-    baud_rate: 9600
-    auto_start: true # See comment on virtual_uart_server above
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true # See comment on virtual_uart_server above
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-          - uart_mock.inject_rx:
-              id: virtual_uart_server_2
-              data: !lambda return data;
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_server_2
-    id: virtual_modbus_server_2
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_client
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_client
-    update_interval: 1s
-    id: modbus_controller_1
-  - address: 2
-    modbus_id: virtual_modbus_client
-    update_interval: 1s
-    id: modbus_controller_2
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    registers:
-      - address: 0x01
-        value_type: U_WORD
-        read_lambda: return 919;
-  - address: 2
-    modbus_id: virtual_modbus_server_2
-    registers:
-      - address: 0x01
-        value_type: U_WORD
-        read_lambda: return 929;
-
-sensor:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_u_word"
-    address: 0x01
-    register_type: holding
-    value_type: U_WORD
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_2
-    name: "reg_u_word_2"
-    address: 0x01
-    register_type: holding
-    value_type: U_WORD
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)

tests/integration/fixtures/uart_mock_modbus_server_injected.yaml

@@ -1,5 +1,5 @@
 esphome:
-  name: uart-mock-modbus-srv-rw
+  name: uart-mock-modbus-srv-injected
 
 host:
 api:
@@ -17,6 +17,8 @@ uart:
   baud_rate: 115200
   port: /dev/null
 
+# Shared server-role fixture (see the shared_yaml markers in the test file);
+# the injections concatenate and each test waits only on its own sensors.
 uart_mock:
   - id: virtual_uart_dev
     baud_rate: 9600
@@ -25,18 +27,31 @@ uart_mock:
     auto_start: false
     debug:
     injections:
-      # FC 0x17 Read/Write Multiple Registers on device 1:
-      #   write reg 0x0001 = 0x1234 (qty 1), then read regs 0x0001..0x0002 (qty 2).
-      # Per Modbus 6.17 the write is performed before the read, so reg 0x0001 must
-      # read back the just-written 0x1234 in the same request.
+      - delay: 100ms
+        inject_rx: [0x01, 0x03, 0x00, 0x03, 0x00, 0x01, 0x74, 0x0A] #  Read holding register 3 on device 1 (basic_read)
+      - delay: 100ms
+        #  Read holding register 7 on device 2, its reply, then read holding
+        #  register 5 on device 1 (read_after_peer_response)
+        inject_rx: [0x02, 0x03, 0x00, 0x07, 0x00, 0x01, 0x35, 0xF8,
+                    0x02, 0x03, 0x02, 0x00, 0xF0, 0xFC,
+                    0x00, 0x01, 0x03, 0x00, 0x05, 0x00, 0x01, 0x94, 0x0B]
+      - delay: 100ms
+        inject_rx: [0x02, 0x03, 0x00, 0x07, 0x00, 0x01, 0x35, 0xF8] #  Read holding register 7 on device 2, with no response
+      - delay: 100ms
+        #  Read holding register 7 on device 2 with no response, then read
+        #  holding register A on device 1 (read_after_peer_timeout)
+        inject_rx: [0x02, 0x03, 0x00, 0x07, 0x00, 0x01, 0x35, 0xF8,
+                    0x01, 0x03, 0x00, 0x0A, 0x00, 0x01, 0xA4, 0x08]
+      # FC 0x17 on device 1: write reg 0x0001 = 0x1234 then read 0x0001..0x0002;
+      # per Modbus 6.17 the write runs first, so 0x0001 must read back 0x1234.
       - delay: 100ms
         inject_rx:
           [0x01, 0x17, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x01, 0x02, 0x12, 0x34, 0x49, 0xD8]
-      # FC 0x17: write reg 0x0003 = 0x5678 (qty 1), then read reg 0x0003 (qty 1) -
+      # FC 0x17: write reg 0x0006 = 0x5678 (qty 1), then read reg 0x0006 (qty 1) -
       # a write and read targeting a different register block.
       - delay: 100ms
         inject_rx:
-          [0x01, 0x17, 0x00, 0x03, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x02, 0x56, 0x78, 0x9B, 0x10]
+          [0x01, 0x17, 0x00, 0x06, 0x00, 0x01, 0x00, 0x06, 0x00, 0x01, 0x02, 0x56, 0x78, 0x8B, 0x55]
 
 globals:
   - id: stored_1
@@ -70,8 +85,18 @@ modbus_server:
         read_lambda: |-
           id(rw_read_2).publish_state(0x00AA);
           return 0x00AA;
-      # Second writable + readable register, targeted by the second request.
       - address: 0x03
+        value_type: U_WORD
+        read_lambda: |-
+          id(basic_read).publish_state(1);
+          return 1;
+      - address: 0x05
+        value_type: U_WORD
+        read_lambda: |-
+          id(read_after_peer_response).publish_state(1);
+          return 1;
+      # Second writable + readable register, targeted by the second FC 0x17 request.
+      - address: 0x06
         value_type: U_WORD
         read_lambda: |-
           id(rw_read_3).publish_state(id(stored_3));
@@ -80,8 +105,22 @@ modbus_server:
           id(stored_3) = x;
           id(rw_write_3).publish_state(x);
           return true;
+      - address: 0x0A
+        value_type: U_WORD
+        read_lambda: |-
+          id(read_after_peer_timeout).publish_state(1);
+          return 1;
 
 sensor:
+  - platform: template
+    name: "basic_read"
+    id: basic_read
+  - platform: template
+    name: "read_after_peer_response"
+    id: read_after_peer_response
+  - platform: template
+    name: "read_after_peer_timeout"
+    id: read_after_peer_timeout
   - platform: template
     name: "rw_write_1"
     id: rw_write_1

tests/integration/host_prefs.py

@@ -1,7 +1,7 @@
 """Helpers for manipulating the host platform's preferences file.
 
 ESPHome's host platform stores preferences in
-``~/.esphome/prefs/<app_name>.prefs`` using a simple binary layout that
+``$ESPHOME_PREFDIR/<app_name>.prefs`` using a simple binary layout that
 mirrors ``HostPreferences::sync()``:
 ``[uint32_t key][uint8_t len][uint8_t data[len]]`` per entry.
 
@@ -11,13 +11,21 @@ boot (e.g. forcing safe mode) or to clear stale state between runs.
 
 from __future__ import annotations
 
+import os
 from pathlib import Path
 import struct
 
 
 def host_prefs_path(device_name: str) -> Path:
-    """Return the on-disk prefs file path for a host-platform device."""
-    return Path.home() / ".esphome" / "prefs" / f"{device_name}.prefs"
+    """Return the on-disk prefs file path for a host-platform device.
+
+    Requires ESPHOME_PREFDIR, which the autouse isolated_preferences fixture
+    sets; refusing the ~/.esphome/prefs fallback keeps tests off real user
+    data if the fixture is ever bypassed."""
+    prefdir = os.environ.get("ESPHOME_PREFDIR")
+    if not prefdir:
+        raise RuntimeError("ESPHOME_PREFDIR is not set; refusing the real prefs dir")
+    return Path(prefdir) / f"{device_name}.prefs"
 
 
 def clear_host_prefs(device_name: str) -> None:

tests/integration/test_api_zero_psk_provisioning.py

@@ -10,34 +10,39 @@ from __future__ import annotations
 
 import asyncio
 import base64
+import socket
 
 from aioesphomeapi import InvalidEncryptionKeyAPIError, RequiresEncryptionAPIError
 import pytest
 
-from .types import APIClientConnectedFactory, RunCompiledFunction
+from .conftest import run_binary_and_wait_for_port
+from .const import KEY_ACTIVATION_DELAY, LOCALHOST, PROVISIONING_PSK, ZERO_PSK
+from .types import (
+    APIClientConnectedFactory,
+    CompileFunction,
+    ConfigWriter,
+    RunCompiledFunction,
+)
 
-# The well-known provisioning PSK: base64 of 32 zero bytes
-ZERO_PSK = base64.b64encode(bytes(32)).decode()
-# A real key to provision
-NEW_KEY = base64.b64encode(b"n" * 32)
-# Time for the device to activate a newly saved key (100ms timer plus margin)
-KEY_ACTIVATION_DELAY = 0.5
-
-
-@pytest.fixture(autouse=True)
-def isolated_preferences(monkeypatch: pytest.MonkeyPatch, tmp_path) -> None:
-    """Keep host preferences per-test so every run starts unprovisioned."""
-    monkeypatch.setenv("ESPHOME_PREFDIR", str(tmp_path / "prefs"))
+NEW_KEY = PROVISIONING_PSK
 
 
 @pytest.mark.asyncio
 async def test_api_zero_psk_provisioning(
     yaml_config: str,
-    run_compiled: RunCompiledFunction,
+    write_yaml_config: ConfigWriter,
+    compile_esphome: CompileFunction,
+    reserved_tcp_port: tuple[int, socket.socket],
     api_client_connected: APIClientConnectedFactory,
 ) -> None:
-    """Exercise the reject paths, then provision a key over the zero-PSK channel."""
-    async with run_compiled(yaml_config):
+    """Exercise the reject paths, provision a key over the zero-PSK channel,
+    and check the key comes back from preferences on the next boot."""
+    port, port_socket = reserved_tcp_port
+    config_path = await write_yaml_config(yaml_config)
+    binary_path = await compile_esphome(config_path)
+    port_socket.close()
+
+    async with run_binary_and_wait_for_port(binary_path, LOCALHOST, port):
         # --- Pre-provisioning reject paths (device state is unchanged) ---
 
         # A wrong (non-zero) PSK fails against the zero provisioning PSK
@@ -97,6 +102,19 @@ async def test_api_zero_psk_provisioning(
             async with api_client_connected(timeout=5) as client:
                 await client.device_info()
 
+    # The key is loaded from preferences on the next boot
+    lines: list[str] = []
+    async with run_binary_and_wait_for_port(
+        binary_path, LOCALHOST, port, line_callback=lines.append
+    ):
+        async with api_client_connected(noise_psk=NEW_KEY.decode()) as client:
+            device_info = await client.device_info()
+            assert device_info.api_encryption_provisionable is False
+        with pytest.raises(InvalidEncryptionKeyAPIError):
+            async with api_client_connected(noise_psk=ZERO_PSK, timeout=5) as client:
+                await client.device_info()
+    assert any("Loaded saved Noise PSK" in line for line in lines)
+
 
 @pytest.mark.asyncio
 async def test_api_zero_psk_provisioning_plaintext(

tests/integration/test_host_ota.py

@@ -8,9 +8,12 @@ instance covers the FD_CLOEXEC path.
 from __future__ import annotations
 
 import asyncio
+import base64
 from collections.abc import Generator
 from contextlib import contextmanager
+from dataclasses import dataclass
 import functools
+from pathlib import Path
 import socket
 
 import pytest
@@ -18,10 +21,18 @@ import pytest
 from esphome import espota2
 
 from .conftest import run_binary, wait_and_connect_api_client
-from .const import LOCALHOST, PORT_POLL_INTERVAL, PORT_WAIT_TIMEOUT
-from .types import CompileFunction, ConfigWriter
+from .const import (
+    KEY_ACTIVATION_DELAY,
+    LOCALHOST,
+    PORT_POLL_INTERVAL,
+    PORT_WAIT_TIMEOUT,
+    PROVISIONING_PSK,
+    ZERO_PSK,
+)
+from .types import APIClientConnectedFactory, CompileFunction, ConfigWriter
 
 DEVICE_NAME = "host-ota-test"
+API_KEY = "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8="
 
 
 @contextmanager
@@ -35,6 +46,14 @@ def _reserve_port() -> Generator[tuple[int, socket.socket]]:
         s.close()
 
 
+async def _wait_for_line(lines: list[str], needle: str, timeout: float = 5.0) -> None:
+    """The config dump prints after every setup, a little after the api port
+    opens, so wait for it rather than assert on the lines seen so far."""
+    async with asyncio.timeout(timeout):
+        while not any(needle in line for line in lines):
+            await asyncio.sleep(PORT_POLL_INTERVAL)
+
+
 async def _wait_for_port(host: str, port: int, timeout: float) -> None:
     """Poll until a TCP port accepts connections, or raise TimeoutError."""
     loop = asyncio.get_running_loop()
@@ -51,6 +70,102 @@ async def _wait_for_port(host: str, port: int, timeout: float) -> None:
     raise TimeoutError(f"Port {port} on {host} did not open within {timeout}s")
 
 
+async def _build(
+    yaml_config: str,
+    write_yaml_config: ConfigWriter,
+    compile_esphome: CompileFunction,
+    reserved_tcp_port: tuple[int, socket.socket],
+) -> tuple[int, int, Path]:
+    """Reserve an OTA port, compile the fixture with it, and release both
+    ports right before the binary is started."""
+    api_port, api_socket = reserved_tcp_port
+    with _reserve_port() as (ota_port, ota_socket):
+        config_path = await write_yaml_config(
+            yaml_config.replace("__OTA_PORT__", str(ota_port))
+        )
+        binary_path = await compile_esphome(config_path)
+        api_socket.close()
+        ota_socket.close()
+    return api_port, ota_port, binary_path
+
+
+async def _run_ota(
+    ota_port: int,
+    password: str | None,
+    binary_path: Path,
+    noise_psk: str | None,
+    plaintext_fallback: bool = False,
+) -> int:
+    """espota2 is blocking; run it in the executor and return its exit code."""
+    rc, _ = await asyncio.get_running_loop().run_in_executor(
+        None,
+        functools.partial(
+            espota2.run_ota,
+            LOCALHOST,
+            ota_port,
+            password,
+            binary_path,
+            noise_psk=noise_psk,
+            plaintext_fallback=plaintext_fallback,
+        ),
+    )
+    return rc
+
+
+@dataclass
+class _Device:
+    """A running host binary and the checks every successful OTA repeats:
+    a safe reboot, the api port back up, and the pid preserved by execv."""
+
+    api_port: int
+    ota_port: int
+    binary_path: Path
+    proc: asyncio.subprocess.Process | None = None
+    reboots: int = 0
+
+    def __post_init__(self) -> None:
+        self._rebooted = asyncio.Event()
+
+    def on_log(self, line: str) -> None:
+        if "Rebooting safely" in line:
+            self.reboots += 1
+            self._rebooted.set()
+
+    async def wait_reboot(self, count: int, timeout: float = 10.0) -> None:
+        async with asyncio.timeout(timeout):
+            while self.reboots < count:
+                self._rebooted.clear()
+                await self._rebooted.wait()
+
+    async def ota(
+        self,
+        password: str | None,
+        noise_psk: str | None,
+        msg: str,
+        plaintext_fallback: bool = False,
+    ) -> None:
+        """Upload, then expect the re-exec with the pid preserved."""
+        pid_before = self.proc.pid
+        expected_reboots = self.reboots + 1
+        rc = await _run_ota(
+            self.ota_port, password, self.binary_path, noise_psk, plaintext_fallback
+        )
+        assert rc == 0, msg
+        await self.wait_reboot(expected_reboots)
+        await _wait_for_port(LOCALHOST, self.api_port, PORT_WAIT_TIMEOUT)
+        assert self.proc.returncode is None, "process exited instead of execing"
+        assert self.proc.pid == pid_before
+
+    async def refused_ota(
+        self, password: str | None, noise_psk: str | None, msg: str
+    ) -> None:
+        """Upload must fail and the device must keep running."""
+        rc = await _run_ota(self.ota_port, password, self.binary_path, noise_psk)
+        assert rc == 1, msg
+        await asyncio.sleep(0.5)
+        assert self.proc.returncode is None, "process died on rejected OTA"
+
+
 @pytest.mark.asyncio
 async def test_host_ota_self_update(
     yaml_config: str,
@@ -59,57 +174,34 @@ async def test_host_ota_self_update(
     reserved_tcp_port: tuple[int, socket.socket],
 ) -> None:
     """Self-OTA: upload the running binary back to itself, expect re-exec."""
-    api_port, api_socket = reserved_tcp_port
-    with _reserve_port() as (ota_port, ota_socket):
-        yaml_config = yaml_config.replace("__OTA_PORT__", str(ota_port))
-        config_path = await write_yaml_config(yaml_config)
-        binary_path = await compile_esphome(config_path)
-        api_socket.close()
-        ota_socket.close()
+    dev = _Device(
+        *await _build(
+            yaml_config, write_yaml_config, compile_esphome, reserved_tcp_port
+        )
+    )
+    staged = asyncio.Event()
 
-        loop = asyncio.get_running_loop()
-        ota_staged = loop.create_future()
-        rebooted = loop.create_future()
+    def on_log(line: str) -> None:
+        if "OTA staged at" in line:
+            staged.set()
+        dev.on_log(line)
 
-        def on_log(line: str) -> None:
-            if not ota_staged.done() and "OTA staged at" in line:
-                ota_staged.set_result(True)
-            if not rebooted.done() and "Rebooting safely" in line:
-                rebooted.set_result(True)
+    async with run_binary(dev.binary_path, line_callback=on_log) as (proc, _lines):
+        dev.proc = proc
+        await _wait_for_port(LOCALHOST, dev.api_port, PORT_WAIT_TIMEOUT)
+        async with wait_and_connect_api_client(port=dev.api_port) as client:
+            info_before = await client.device_info()
+            assert info_before.name == DEVICE_NAME
 
-        async with run_binary(binary_path, line_callback=on_log) as (proc, _lines):
-            await _wait_for_port(LOCALHOST, api_port, PORT_WAIT_TIMEOUT)
-            pid_before = proc.pid
-            async with wait_and_connect_api_client(port=api_port) as client:
-                info_before = await client.device_info()
-                assert info_before.name == DEVICE_NAME
+        await dev.ota(None, None, "espota2 reported failure")
+        assert staged.is_set()
 
-            # espota2 is blocking; run in executor.
-            rc, _ = await loop.run_in_executor(
-                None, espota2.run_ota, LOCALHOST, ota_port, None, binary_path
-            )
-            assert rc == 0, "espota2 reported failure"
+        async with wait_and_connect_api_client(port=dev.api_port) as client:
+            info_after = await client.device_info()
+            assert info_after.name == info_before.name
 
-            await asyncio.wait_for(ota_staged, timeout=10.0)
-            await asyncio.wait_for(rebooted, timeout=10.0)
-            await _wait_for_port(LOCALHOST, api_port, PORT_WAIT_TIMEOUT)
-
-            # execv preserves pid; mismatch means external respawn.
-            assert proc.returncode is None, "process exited instead of execing"
-            assert proc.pid == pid_before
-
-            async with wait_and_connect_api_client(port=api_port) as client:
-                info_after = await client.device_info()
-                assert info_after.name == DEVICE_NAME
-                assert info_after.name == info_before.name
-
-            # Second OTA: catches FD_CLOEXEC regressions (EADDRINUSE on rebind).
-            rc, _ = await loop.run_in_executor(
-                None, espota2.run_ota, LOCALHOST, ota_port, None, binary_path
-            )
-            assert rc == 0, "second OTA failed -- listener leaked across execv"
-            await _wait_for_port(LOCALHOST, api_port, PORT_WAIT_TIMEOUT)
-            assert proc.pid == pid_before
+        # Second OTA: catches FD_CLOEXEC regressions (EADDRINUSE on rebind).
+        await dev.ota(None, None, "second OTA failed -- listener leaked across execv")
 
 
 @pytest.mark.asyncio
@@ -121,51 +213,110 @@ async def test_host_ota_encrypted(
 ) -> None:
     """Encrypted self-OTA succeeds; a plaintext upload to the same device fails."""
     pytest.importorskip("aioesphomeapi.noise")
-    noise_psk = "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8="
-    api_port, api_socket = reserved_tcp_port
-    with _reserve_port() as (ota_port, ota_socket):
-        yaml_config = yaml_config.replace("__OTA_PORT__", str(ota_port))
-        config_path = await write_yaml_config(yaml_config)
-        binary_path = await compile_esphome(config_path)
-        api_socket.close()
-        ota_socket.close()
+    dev = _Device(
+        *await _build(
+            yaml_config, write_yaml_config, compile_esphome, reserved_tcp_port
+        )
+    )
+    async with run_binary(dev.binary_path, line_callback=dev.on_log) as (proc, _lines):
+        dev.proc = proc
+        await _wait_for_port(LOCALHOST, dev.api_port, PORT_WAIT_TIMEOUT)
+        await dev.refused_ota(
+            None, None, "plaintext upload to an encrypted device must fail"
+        )
+        await dev.ota(None, API_KEY, "encrypted OTA reported failure")
 
-        loop = asyncio.get_running_loop()
-        rebooted = loop.create_future()
 
-        def on_log(line: str) -> None:
-            if not rebooted.done() and "Rebooting safely" in line:
-                rebooted.set_result(True)
+@pytest.mark.asyncio
+async def test_host_ota_api_key_offer_with_password(
+    yaml_config: str,
+    write_yaml_config: ConfigWriter,
+    compile_esphome: CompileFunction,
+    reserved_tcp_port: tuple[int, socket.socket],
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """With only an api key the device offers encryption without requiring
+    it: the password still guards plaintext uploads, the key alone
+    authenticates an encrypted one, and until 2027.3.0 a failed encrypted
+    attempt falls back to plaintext."""
+    pytest.importorskip("aioesphomeapi.noise")
+    wrong_key = base64.b64encode(b"w" * 32).decode()
+    dev = _Device(
+        *await _build(
+            yaml_config, write_yaml_config, compile_esphome, reserved_tcp_port
+        )
+    )
+    async with run_binary(dev.binary_path, line_callback=dev.on_log) as (proc, lines):
+        dev.proc = proc
+        await _wait_for_port(LOCALHOST, dev.api_port, PORT_WAIT_TIMEOUT)
+        await _wait_for_line(lines, "Encryption: offered")
 
-        async with run_binary(binary_path, line_callback=on_log) as (proc, _lines):
-            await _wait_for_port(LOCALHOST, api_port, PORT_WAIT_TIMEOUT)
-            pid_before = proc.pid
+        await dev.refused_ota(
+            None, None, "plaintext upload without the password must fail"
+        )
+        await dev.ota(
+            "hunter2", None, "plaintext upload with the password must succeed"
+        )
+        await dev.ota(None, API_KEY, "encrypted upload with the api key must succeed")
 
-            # A plaintext upload must be refused with the device unharmed
-            rc, _ = await loop.run_in_executor(
-                None, espota2.run_ota, LOCALHOST, ota_port, None, binary_path
+        # Remove before 2027.3.0: a wrong key falls back to plaintext, which
+        # the password still guards
+        with caplog.at_level("WARNING", logger="esphome.espota2"):
+            await dev.ota(
+                "hunter2",
+                wrong_key,
+                "the plaintext retry with the password must succeed",
+                plaintext_fallback=True,
             )
-            assert rc == 1, "plaintext upload to an encrypted device must fail"
-            await asyncio.sleep(0.5)
-            assert proc.returncode is None, "process died on rejected plaintext OTA"
+        assert any("Retrying in plaintext" in r.message for r in caplog.records)
+        await dev.ota(
+            None,
+            API_KEY,
+            "the right api key encrypts without touching the fallback",
+            plaintext_fallback=True,
+        )
 
-            # The encrypted upload goes through and the device re-execs
-            rc, _ = await loop.run_in_executor(
-                None,
-                functools.partial(
-                    espota2.run_ota,
-                    LOCALHOST,
-                    ota_port,
-                    None,
-                    binary_path,
-                    noise_psk=noise_psk,
-                ),
-            )
-            assert rc == 0, "encrypted OTA reported failure"
-            await asyncio.wait_for(rebooted, timeout=10.0)
-            await _wait_for_port(LOCALHOST, api_port, PORT_WAIT_TIMEOUT)
-            assert proc.returncode is None, "process exited instead of execing"
-            assert proc.pid == pid_before
+
+@pytest.mark.asyncio
+@pytest.mark.usefixtures("isolated_preferences")
+async def test_host_ota_provisioned_api_key(
+    yaml_config: str,
+    write_yaml_config: ConfigWriter,
+    compile_esphome: CompileFunction,
+    reserved_tcp_port: tuple[int, socket.socket],
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """A key provisioned over the api feeds the OTA offer: plaintext works
+    while unprovisioned, the provisioned key encrypts, the key loaded from
+    preferences on the next boot keeps encrypting, and plaintext stays
+    accepted because only the ota block requires encryption."""
+    pytest.importorskip("aioesphomeapi.noise")
+    dev = _Device(
+        *await _build(
+            yaml_config, write_yaml_config, compile_esphome, reserved_tcp_port
+        )
+    )
+    async with run_binary(dev.binary_path, line_callback=dev.on_log) as (proc, lines):
+        dev.proc = proc
+        await _wait_for_port(LOCALHOST, dev.api_port, PORT_WAIT_TIMEOUT)
+        await _wait_for_line(lines, "once the api key is provisioned")
+
+        await dev.ota(
+            None, None, "plaintext upload to an unprovisioned device must succeed"
+        )
+
+        async with api_client_connected(
+            port=dev.api_port, noise_psk=ZERO_PSK
+        ) as client:
+            assert await client.noise_encryption_set_key(PROVISIONING_PSK) is True
+        await asyncio.sleep(KEY_ACTIVATION_DELAY)
+
+        key = PROVISIONING_PSK.decode()
+        await dev.ota(
+            None, key, "encrypted upload with the provisioned key must succeed"
+        )
+        await dev.ota(None, key, "the key loaded at boot must feed the OTA offer")
+        await dev.ota(None, None, "plaintext must stay accepted on an offering device")
 
 
 @pytest.mark.asyncio
@@ -177,33 +328,25 @@ async def test_host_ota_rejects_garbage(
     integration_test_dir,
 ) -> None:
     """Bogus payload is rejected and the device keeps running."""
-    api_port, api_socket = reserved_tcp_port
-    with _reserve_port() as (ota_port, ota_socket):
-        yaml_config = yaml_config.replace("__OTA_PORT__", str(ota_port))
-        config_path = await write_yaml_config(yaml_config)
-        binary_path = await compile_esphome(config_path)
+    dev = _Device(
+        *await _build(
+            yaml_config, write_yaml_config, compile_esphome, reserved_tcp_port
+        )
+    )
+    # 192 bytes that are neither ELF nor Mach-O.
+    bogus_path = integration_test_dir / "bogus.bin"
+    bogus_path.write_bytes(b"NOT-AN-EXECUTABLE-AT-ALL" * 8)
 
-        # 192 bytes that are neither ELF nor Mach-O.
-        bogus_path = integration_test_dir / "bogus.bin"
-        bogus_path.write_bytes(b"NOT-AN-EXECUTABLE-AT-ALL" * 8)
+    async with run_binary(dev.binary_path) as (proc, _lines):
+        dev.proc = proc
+        await _wait_for_port(LOCALHOST, dev.api_port, PORT_WAIT_TIMEOUT)
+        pid_before = proc.pid
+        rc = await _run_ota(dev.ota_port, None, bogus_path, None)
+        assert rc == 1
+        await asyncio.sleep(0.5)
+        assert proc.returncode is None, "process died on rejected OTA"
+        assert proc.pid == pid_before
 
-        api_socket.close()
-        ota_socket.close()
-
-        async with run_binary(binary_path) as (proc, _lines):
-            await _wait_for_port(LOCALHOST, api_port, PORT_WAIT_TIMEOUT)
-            pid_before = proc.pid
-
-            loop = asyncio.get_running_loop()
-            rc, _ = await loop.run_in_executor(
-                None, espota2.run_ota, LOCALHOST, ota_port, None, bogus_path
-            )
-            assert rc == 1
-
-            await asyncio.sleep(0.5)
-            assert proc.returncode is None, "process died on rejected OTA"
-            assert proc.pid == pid_before
-
-            async with wait_and_connect_api_client(port=api_port) as client:
-                info = await client.device_info()
-                assert info.name == DEVICE_NAME
+        async with wait_and_connect_api_client(port=dev.api_port) as client:
+            info = await client.device_info()
+            assert info.name == DEVICE_NAME

tests/integration/test_host_preferences_suspend_resume.py

@@ -41,15 +41,6 @@ async def _poll_until_exists(path: Path) -> None:
         await asyncio.sleep(0.05)
 
 
-@pytest.fixture(autouse=True)
-def isolated_preferences(monkeypatch: pytest.MonkeyPatch, tmp_path) -> Path:
-    """Keep host preferences per-test so this test never touches the real
-    ~/.esphome/prefs and never races other tests over ESPHOME_PREFDIR."""
-    prefdir = tmp_path / "prefs"
-    monkeypatch.setenv("ESPHOME_PREFDIR", str(prefdir))
-    return prefdir / f"{DEVICE_NAME}.prefs"
-
-
 @pytest.mark.asyncio
 async def test_host_preferences_suspend_resume(
     yaml_config: str,
@@ -58,7 +49,7 @@ async def test_host_preferences_suspend_resume(
     isolated_preferences: Path,
 ) -> None:
     """Test that a running syncer flushes, a suspended one doesn't, and resume restores flushing."""
-    pref_file = isolated_preferences
+    pref_file = isolated_preferences / f"{DEVICE_NAME}.prefs"
 
     loop = asyncio.get_running_loop()
     saved_in_memory = loop.create_future()

tests/integration/test_light_initial_state.py

@@ -11,14 +11,6 @@ from .state_utils import InitialStateHelper, require_entity
 from .types import APIClientConnectedFactory, RunCompiledFunction
 
 
-@pytest.fixture(autouse=True)
-def isolated_preferences(monkeypatch: pytest.MonkeyPatch, tmp_path) -> None:
-    """Keep host preferences per-test so RESTORE_AND_ON never loads a stale value left
-    behind by a previous run (host preferences otherwise persist to ~/.esphome/prefs,
-    keyed only by device name)."""
-    monkeypatch.setenv("ESPHOME_PREFDIR", str(tmp_path / "prefs"))
-
-
 @pytest.mark.asyncio
 async def test_light_initial_state(
     yaml_config: str,

tests/integration/test_lvgl_headless_render.py

@@ -0,0 +1,83 @@
+"""Integration test that checks what LVGL actually draws, using a display with no screen.
+
+The rendered screen is compared against a hash rather than a checked in reference image, so the
+repository does not have to carry a binary file. If a change to the drawing code or to the bundled
+LVGL alters the output, this test fails and prints the hash it saw; update EXPECTED_SHA256 once the
+new image has been looked at and found to be correct.
+
+The picture is drawn and encoded entirely by code in this repository, so nothing installed on the
+machine running the test takes part in the result.
+"""
+
+from __future__ import annotations
+
+import hashlib
+from pathlib import Path
+
+import pytest
+
+from .artifact_utils import keep_artifact
+from .bmp_utils import capture_when_drawn
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+WIDTH = 300
+HEIGHT = 300
+
+# sha256 of the pixel data of a 300x300 screen showing "Hello World!" centred in white on a dark
+# blue background, drawn with the built in montserrat_14 font. To regenerate, run this test and
+# take the hash it reports.
+EXPECTED_SHA256 = "a995b002dd1d183c47514da15ab9a60a3e7d788c2e24386a02fddd48655092ed"
+# Bundled LVGL version (esphome/components/lvgl/__init__.py, LVGL_VERSION) the hash above was
+# generated against. A version bump can shift anti-aliasing enough to change the hash even though
+# nothing is actually wrong -- if this test fails, check that first before regenerating the hash.
+EXPECTED_LVGL_VERSION = "9.5.0"
+
+
+@pytest.mark.asyncio
+async def test_lvgl_headless_render(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """LVGL draws the expected screen on a 300x300 display with no screen behind it."""
+    snapshot_dir = tmp_path / "snapshots"
+    monkeypatch.setenv("ESPHOME_SNAPSHOT_DIR", str(snapshot_dir))
+
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        _, services = await client.list_entities_services()
+        service = next(s for s in services if s.name == "take_screenshot")
+
+        async def take(name: str) -> None:
+            await client.execute_service(service, {"name": name})
+
+        # The background is not the whole picture: LVGL must have drawn on it. Waiting for that
+        # rather than for a fixed time keeps a slow first frame from being reported as a hash
+        # mismatch, which would look like a drawing regression.
+        image, capture = await capture_when_drawn(take, snapshot_dir, prefix="render")
+        assert (image.width, image.height, image.bits) == (WIDTH, HEIGHT, 24)
+
+        digest = hashlib.sha256(image.pixels).hexdigest()
+        if digest != EXPECTED_SHA256:
+            # Kept outside the temporary folder so CI can upload it; see artifact_utils.
+            kept = keep_artifact(
+                "lvgl_headless_render_actual.bmp", capture.read_bytes()
+            )
+
+            from esphome.components.lvgl import LVGL_VERSION
+
+            version_hint = ""
+            if LVGL_VERSION != EXPECTED_LVGL_VERSION:
+                version_hint = (
+                    f"the bundled LVGL version changed ({EXPECTED_LVGL_VERSION} -> "
+                    f"{LVGL_VERSION}), which is the likely cause\n"
+                )
+            pytest.fail(
+                f"rendered screen does not match the expected hash\n"
+                f"{version_hint}"
+                f"  expected: {EXPECTED_SHA256}\n"
+                f"  actual:   {digest}\n"
+                f"the image that was rendered has been kept at {kept}\n"
+                f"on CI it is in the integration-test-artifacts upload for this job"
+            )

tests/integration/test_sdl_headless_screenshot.py

@@ -0,0 +1,49 @@
+"""Integration test for headless SDL rendering and snapshot capture.
+
+How a file is named and written is the same for every display that can take a snapshot and is
+covered by test_snapshot_display; what is tested here is that SDL renders and can be read back
+with no display server present.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+
+from .bmp_utils import capture_when_drawn
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+WIDTH = 101
+HEIGHT = 64
+
+
+@pytest.mark.asyncio
+async def test_sdl_headless_screenshot(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """A headless SDL display renders with no display server and can be captured."""
+    snapshot_dir = tmp_path / "snapshots"
+    # The device reads this when it writes a file; the subprocess inherits our environment, so it
+    # must be set before the binary is launched.
+    monkeypatch.setenv("ESPHOME_SNAPSHOT_DIR", str(snapshot_dir))
+    # Make sure the run really is headless even when the test machine has a display.
+    monkeypatch.delenv("DISPLAY", raising=False)
+    monkeypatch.delenv("WAYLAND_DISPLAY", raising=False)
+
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        _, services = await client.list_entities_services()
+        service = next(s for s in services if s.name == "take_screenshot")
+
+        async def take(name: str) -> None:
+            await client.execute_service(service, {"name": name})
+
+        # The test card is drawn in several colours, so once it is on the screen the picture is
+        # not one flat shade. Capturing until that is true waits out the first update rather than
+        # racing it.
+        image, _ = await capture_when_drawn(take, snapshot_dir)
+        assert (image.width, image.height, image.bits) == (WIDTH, HEIGHT, 24)

tests/integration/test_snapshot_display.py

@@ -0,0 +1,78 @@
+"""Integration test for the snapshot display and the file writing shared with other displays."""
+
+from __future__ import annotations
+
+import asyncio
+from pathlib import Path
+
+from aioesphomeapi import LogLevel
+import pytest
+
+from .bmp_utils import capture_when_drawn, wait_for_bmp
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+WIDTH = 101
+HEIGHT = 64
+
+# Part of the message the writer logs when it will not write over a file that is already there.
+REFUSAL_MESSAGE = b"not overwriting"
+
+
+@pytest.mark.asyncio
+async def test_snapshot_display(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """A display with no screen draws into memory and writes what it drew to a file."""
+    snapshot_dir = tmp_path / "snapshots"
+    # The device reads this when it writes a file; the subprocess inherits our environment, so it
+    # must be set before the binary is launched.
+    monkeypatch.setenv("ESPHOME_SNAPSHOT_DIR", str(snapshot_dir))
+
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        _, services = await client.list_entities_services()
+        service = next(s for s in services if s.name == "take_snapshot")
+
+        async def take(name: str) -> None:
+            await client.execute_service(service, {"name": name})
+
+        # The test card is drawn in several colours, so once it is on the screen the picture is
+        # not one flat shade. Capturing until that is true waits out the first update rather than
+        # racing it.
+        image, capture = await capture_when_drawn(take, snapshot_dir)
+        assert (image.width, image.height, image.bits) == (WIDTH, HEIGHT, 24)
+
+        # An extension is only added when there is not one already, whatever its case.
+        await take("UPPER.BMP")
+        await wait_for_bmp(snapshot_dir / "UPPER.BMP")
+
+        # A name that tries to lead somewhere else is cut back to one harmless name in the
+        # snapshot directory.
+        await take("../escape")
+        await wait_for_bmp(snapshot_dir / ".._escape.bmp")
+
+        # A second capture under a name already used must fail rather than write over the first.
+        # Wait for the device to report the refusal: on its own, an unchanged file cannot tell a
+        # refusal apart from a request the device has not got to yet, so a regression that wrote
+        # over the file could still pass on a busy machine.
+        refused = asyncio.Event()
+
+        def on_log(msg) -> None:
+            if REFUSAL_MESSAGE in msg.message:
+                refused.set()
+
+        client.subscribe_logs(on_log, log_level=LogLevel.LOG_LEVEL_DEBUG)
+
+        before = capture.read_bytes()
+        await take(capture.name)
+        await asyncio.wait_for(refused.wait(), timeout=10.0)
+        assert capture.read_bytes() == before
+        # Nothing beyond what was asked for, leaving out however many captures it took to wait
+        # for the first frame.
+        written = sorted(
+            p.name for p in snapshot_dir.iterdir() if not p.name.startswith("drawn-")
+        )
+        assert written == [".._escape.bmp", "UPPER.BMP"]

tests/integration/test_template_climate_basic.py

@@ -0,0 +1,146 @@
+"""Integration test for template climate: sensor-pushed measured values, on_control + publish
+for the settable ones.
+
+current_temperature/current_humidity are pushed by a referenced sensor/humidity_sensor (no
+polling); action is set once at boot via climate.template.publish, since it has no sensor
+equivalent. mode/target_temperature/fan_mode/swing_mode/preset are plain internal state:
+on_control fires exactly once per command (never before the first one), and
+climate.template.publish simulates the device reporting its own state independent of any prior
+command -- that report is authoritative, overriding whatever was optimistically applied earlier.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import aioesphomeapi
+from aioesphomeapi import (
+    ButtonInfo,
+    ClimateAction,
+    ClimateFanMode,
+    ClimateInfo,
+    ClimateMode,
+    ClimatePreset,
+    ClimateSwingMode,
+)
+import pytest
+
+from .host_prefs import clear_host_prefs
+from .state_utils import InitialStateHelper, require_entity, wait_for_state
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+DEVICE_NAME = "tmpl-clim-basic"
+
+
+@pytest.mark.asyncio
+async def test_template_climate_basic(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Sensor-pushed measured values, on_control + publish for settable ones."""
+    clear_host_prefs(DEVICE_NAME)
+
+    log_lines: list[str] = []
+
+    def on_log_line(line: str) -> None:
+        if "on_control " in line:
+            log_lines.append(line)
+
+    async with (
+        run_compiled(yaml_config, line_callback=on_log_line),
+        api_client_connected() as client,
+    ):
+
+        async def wait_for_climate_state(
+            timeout: float = 5.0,
+        ) -> aioesphomeapi.ClimateState:
+            return await wait_for_state(
+                client, lambda s: isinstance(s, aioesphomeapi.ClimateState), timeout
+            )
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        climate_infos = [e for e in entities if isinstance(e, ClimateInfo)]
+        assert len(climate_infos) == 1, "Expected exactly 1 climate entity"
+        test_climate = climate_infos[0]
+
+        # Advertised capabilities come straight from the supported_*/custom_* config lists.
+        assert ClimateMode.OFF in test_climate.supported_modes
+        assert ClimateMode.HEAT in test_climate.supported_modes
+        assert ClimateMode.COOL in test_climate.supported_modes
+
+        assert ClimateFanMode.AUTO in test_climate.supported_fan_modes
+        assert ClimateFanMode.LOW in test_climate.supported_fan_modes
+        assert ClimateFanMode.HIGH in test_climate.supported_fan_modes
+
+        assert ClimateSwingMode.OFF in test_climate.supported_swing_modes
+        assert ClimateSwingMode.VERTICAL in test_climate.supported_swing_modes
+
+        assert ClimatePreset.NONE in test_climate.supported_presets
+        assert ClimatePreset.ECO in test_climate.supported_presets
+
+        report_button = require_entity(entities, "simulate_device_report", ButtonInfo)
+
+        client.subscribe_states(
+            initial_state_helper.on_state_wrapper(lambda state: None)
+        )
+        try:
+            await initial_state_helper.wait_for_initial_states()
+        except TimeoutError:
+            pytest.fail("Timeout waiting for initial states")
+
+        initial = initial_state_helper.initial_states.get(test_climate.key)
+        assert initial is not None, "No initial climate state received"
+        assert isinstance(initial, aioesphomeapi.ClimateState)
+        assert initial.current_temperature == pytest.approx(22.5, abs=0.1)
+        assert initial.current_humidity == pytest.approx(55.0, abs=0.1)
+        assert initial.action == ClimateAction.IDLE
+        assert initial.mode == ClimateMode.OFF
+        # Nothing was commanded yet: on_control must not have fired.
+        assert not log_lines
+
+        # Commands apply optimistically and on_control fires with the same values.
+        client.climate_command(test_climate.key, mode=ClimateMode.HEAT)
+        state = await wait_for_climate_state()
+        assert state.mode == ClimateMode.HEAT
+
+        client.climate_command(test_climate.key, target_temperature=22.5)
+        state = await wait_for_climate_state()
+        assert state.target_temperature == pytest.approx(22.5, abs=0.1)
+
+        client.climate_command(test_climate.key, fan_mode=ClimateFanMode.HIGH)
+        state = await wait_for_climate_state()
+        assert state.fan_mode == ClimateFanMode.HIGH
+
+        client.climate_command(test_climate.key, swing_mode=ClimateSwingMode.VERTICAL)
+        state = await wait_for_climate_state()
+        assert state.swing_mode == ClimateSwingMode.VERTICAL
+
+        client.climate_command(test_climate.key, preset=ClimatePreset.ECO)
+        state = await wait_for_climate_state()
+        assert state.preset == ClimatePreset.ECO
+
+        await asyncio.sleep(0.2)
+        assert any(
+            "on_control mode=3" in line for line in log_lines
+        )  # CLIMATE_MODE_HEAT
+        assert any("on_control target_temperature=22.5" in line for line in log_lines)
+        assert any("on_control fan_mode=" in line for line in log_lines)
+        assert any("on_control swing_mode=" in line for line in log_lines)
+        assert any("on_control preset=" in line for line in log_lines)
+        # Exactly one on_control log line per command, none extra (e.g. from a stray republish).
+        assert len(log_lines) == 5
+
+        # measured values are untouched by any of the above (no set action exists for them).
+        assert state.current_temperature == pytest.approx(22.5, abs=0.1)
+        assert state.current_humidity == pytest.approx(55.0, abs=0.1)
+        assert state.action == ClimateAction.IDLE
+
+        # The device's report is authoritative and overrides everything commanded above.
+        client.button_command(report_button.key)
+        state = await wait_for_climate_state()
+        assert state.mode == ClimateMode.OFF
+        assert state.fan_mode == ClimateFanMode.AUTO
+        assert state.swing_mode == ClimateSwingMode.OFF
+        assert state.preset == ClimatePreset.NONE

tests/integration/test_template_climate_custom_modes.py

@@ -0,0 +1,98 @@
+"""Integration test for template climate: custom fan modes and presets.
+
+Same on_control (forward) + climate.template.publish (device report, authoritative) pattern as
+the enum-based mode/preset fields, but for the custom string variants.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import aioesphomeapi
+from aioesphomeapi import ButtonInfo, ClimateInfo
+import pytest
+
+from .host_prefs import clear_host_prefs
+from .state_utils import InitialStateHelper, require_entity, wait_for_state
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+DEVICE_NAME = "tmpl-clim-custom"
+
+
+@pytest.mark.asyncio
+async def test_template_climate_custom_modes(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Custom fan mode/preset: traits, on_control forwarding, and publish precedence."""
+    clear_host_prefs(DEVICE_NAME)
+
+    log_lines: list[str] = []
+
+    def on_log_line(line: str) -> None:
+        if "on_control " in line:
+            log_lines.append(line)
+
+    async with (
+        run_compiled(yaml_config, line_callback=on_log_line),
+        api_client_connected() as client,
+    ):
+
+        async def wait_for_climate_state(
+            timeout: float = 5.0,
+        ) -> aioesphomeapi.ClimateState:
+            return await wait_for_state(
+                client, lambda s: isinstance(s, aioesphomeapi.ClimateState), timeout
+            )
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        climate_infos = [e for e in entities if isinstance(e, ClimateInfo)]
+        assert len(climate_infos) == 1, "Expected exactly 1 climate entity"
+        test_climate = climate_infos[0]
+
+        assert set(test_climate.supported_custom_fan_modes) == {
+            "turbo",
+            "silent",
+            "eco",
+        }
+        assert set(test_climate.supported_custom_presets) == {
+            "eco_plus",
+            "power_save",
+            "max",
+        }
+
+        report_button = require_entity(entities, "simulate_device_report", ButtonInfo)
+
+        client.subscribe_states(
+            initial_state_helper.on_state_wrapper(lambda state: None)
+        )
+        try:
+            await initial_state_helper.wait_for_initial_states()
+        except TimeoutError:
+            pytest.fail("Timeout waiting for initial states")
+
+        initial = initial_state_helper.initial_states.get(test_climate.key)
+        assert initial is not None, "No initial climate state received"
+        assert isinstance(initial, aioesphomeapi.ClimateState)
+        assert initial.custom_fan_mode == ""
+        assert initial.custom_preset == ""
+
+        client.climate_command(test_climate.key, custom_fan_mode="turbo")
+        state = await wait_for_climate_state()
+        assert state.custom_fan_mode == "turbo"
+
+        client.climate_command(test_climate.key, custom_preset="power_save")
+        state = await wait_for_climate_state()
+        assert state.custom_preset == "power_save"
+
+        await asyncio.sleep(0.2)
+        assert any("on_control custom_fan_mode=turbo" in line for line in log_lines)
+        assert any("on_control custom_preset=power_save" in line for line in log_lines)
+
+        # The device's report is authoritative and overrides what was commanded above.
+        client.button_command(report_button.key)
+        state = await wait_for_climate_state()
+        assert state.custom_fan_mode == "eco"
+        assert state.custom_preset == "max"

tests/integration/test_template_climate_nonoptimistic.py

@@ -0,0 +1,107 @@
+"""Integration test for template climate: optimistic: false.
+
+A command still fires on_control (so a real device-backed config can forward it out), but must
+NOT change the entity's own state -- only an explicit climate.template.publish call (standing in
+for the device confirming the command actually took effect) does that.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import aioesphomeapi
+from aioesphomeapi import (
+    ButtonInfo,
+    ClimateFanMode,
+    ClimateInfo,
+    ClimateMode,
+    ClimatePreset,
+    ClimateSwingMode,
+)
+import pytest
+
+from .host_prefs import clear_host_prefs
+from .state_utils import InitialStateHelper, require_entity, wait_for_state
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+DEVICE_NAME = "tmpl-clim-nonopt"
+
+
+@pytest.mark.asyncio
+async def test_template_climate_nonoptimistic(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Nonoptimistic: a command doesn't change state until explicitly published."""
+    clear_host_prefs(DEVICE_NAME)
+
+    log_lines: list[str] = []
+    state_updates: list[aioesphomeapi.ClimateState] = []
+
+    def on_log_line(line: str) -> None:
+        if "on_control " in line:
+            log_lines.append(line)
+
+    async with (
+        run_compiled(yaml_config, line_callback=on_log_line),
+        api_client_connected() as client,
+    ):
+
+        def on_state(state: aioesphomeapi.EntityState) -> None:
+            if isinstance(state, aioesphomeapi.ClimateState):
+                state_updates.append(state)
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        climate_infos = [e for e in entities if isinstance(e, ClimateInfo)]
+        assert len(climate_infos) == 1, "Expected exactly 1 climate entity"
+        test_climate = climate_infos[0]
+
+        confirm_button = require_entity(
+            entities, "simulate_device_confirmation", ButtonInfo
+        )
+
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+        try:
+            await initial_state_helper.wait_for_initial_states()
+        except TimeoutError:
+            pytest.fail("Timeout waiting for initial states")
+
+        initial = initial_state_helper.initial_states.get(test_climate.key)
+        assert initial is not None, "No initial climate state received"
+        assert isinstance(initial, aioesphomeapi.ClimateState)
+        assert initial.mode == ClimateMode.OFF
+
+        # Send every settable field in one command. on_control must fire with all of them, but
+        # nothing may be applied to the entity's own state -- no ClimateState update at all.
+        client.climate_command(
+            test_climate.key,
+            mode=ClimateMode.HEAT,
+            target_temperature=22.5,
+            fan_mode=ClimateFanMode.HIGH,
+            swing_mode=ClimateSwingMode.VERTICAL,
+            preset=ClimatePreset.AWAY,
+        )
+        await asyncio.sleep(0.3)
+        assert any(
+            "on_control mode=3" in line for line in log_lines
+        )  # CLIMATE_MODE_HEAT
+        assert any("on_control target_temperature=22.5" in line for line in log_lines)
+        assert any("on_control fan_mode=" in line for line in log_lines)
+        assert any("on_control swing_mode=" in line for line in log_lines)
+        assert any("on_control preset=" in line for line in log_lines)
+        assert not state_updates, (
+            "optimistic: false must not publish a state until climate.template.publish reports it"
+        )
+
+        # The device confirms the command actually took effect.
+        client.button_command(confirm_button.key)
+        state = await wait_for_state(
+            client, lambda s: isinstance(s, aioesphomeapi.ClimateState)
+        )
+        assert state.mode == ClimateMode.HEAT
+        assert state.target_temperature == pytest.approx(22.5, abs=0.1)
+        assert state.fan_mode == ClimateFanMode.HIGH
+        assert state.swing_mode == ClimateSwingMode.VERTICAL
+        assert state.preset == ClimatePreset.AWAY

tests/integration/test_template_climate_on_control_ordering.py

@@ -0,0 +1,83 @@
+"""Integration test: on_control fires before control()/on_state, with the full ClimateCall.
+
+on_control's lambda argument exposes get_mode()/etc. on the *requested* ClimateCall, while the
+entity's own .mode field still reflects the state *before* control() applies the change --
+proving the firing order is on_control, then control(), then on_state.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import aioesphomeapi
+from aioesphomeapi import ClimateInfo, ClimateMode
+import pytest
+
+from .host_prefs import clear_host_prefs
+from .state_utils import InitialStateHelper, wait_for_state
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+DEVICE_NAME = "tmpl-clim-oc-order"
+
+
+@pytest.mark.asyncio
+async def test_template_climate_on_control_ordering(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """on_control sees the requested value while the entity's own state is still the old one."""
+    clear_host_prefs(DEVICE_NAME)
+
+    log_lines: list[str] = []
+
+    def on_log_line(line: str) -> None:
+        if "on_control " in line or "on_state " in line:
+            log_lines.append(line)
+
+    async with (
+        run_compiled(yaml_config, line_callback=on_log_line),
+        api_client_connected() as client,
+    ):
+
+        async def wait_for_climate_state(
+            timeout: float = 5.0,
+        ) -> aioesphomeapi.ClimateState:
+            return await wait_for_state(
+                client, lambda s: isinstance(s, aioesphomeapi.ClimateState), timeout
+            )
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        climate_infos = [e for e in entities if isinstance(e, ClimateInfo)]
+        assert len(climate_infos) == 1, "Expected exactly 1 climate entity"
+        test_climate = climate_infos[0]
+
+        client.subscribe_states(
+            initial_state_helper.on_state_wrapper(lambda state: None)
+        )
+        try:
+            await initial_state_helper.wait_for_initial_states()
+        except TimeoutError:
+            pytest.fail("Timeout waiting for initial states")
+
+        client.climate_command(test_climate.key, mode=ClimateMode.HEAT)
+        state = await wait_for_climate_state()
+        assert state.mode == ClimateMode.HEAT
+
+        await asyncio.sleep(0.2)
+
+        # on_control saw the new requested mode (3 == CLIMATE_MODE_HEAT) while the entity's own
+        # state was still the old one (0 == CLIMATE_MODE_OFF) -- proving it fired before control().
+        assert any(
+            "on_control requested_mode=3 current_mode_before_apply=0" in line
+            for line in log_lines
+        )
+        # on_state fired afterward, reporting the now-applied mode.
+        assert any("on_state mode=3" in line for line in log_lines)
+
+        control_index = next(
+            i for i, line in enumerate(log_lines) if "on_control " in line
+        )
+        state_index = next(i for i, line in enumerate(log_lines) if "on_state " in line)
+        assert control_index < state_index, "on_control must fire before on_state"

tests/integration/test_template_climate_publish_all_fields.py

@@ -0,0 +1,96 @@
+"""Integration test for template climate: climate.template.publish covering every field at once.
+
+A single climate.template.publish call resolves into exactly one ClimateState update, and never
+triggers on_control (which would misrepresent a device state report as a fresh command). This also
+exercises that a sensor/humidity_sensor whose reading matches what's about to be published doesn't
+sneak in an extra state update of its own (the sensor callback only re-publishes on an actual
+change).
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import aioesphomeapi
+from aioesphomeapi import (
+    ButtonInfo,
+    ClimateAction,
+    ClimateFanMode,
+    ClimateInfo,
+    ClimateMode,
+    ClimatePreset,
+    ClimateSwingMode,
+)
+import pytest
+
+from .host_prefs import clear_host_prefs
+from .state_utils import InitialStateHelper, require_entity, wait_for_state
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+DEVICE_NAME = "tmpl-clim-publish-all"
+
+
+@pytest.mark.asyncio
+async def test_template_climate_publish_all_fields(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """One climate.template.publish call setting every field resolves to one state update."""
+    clear_host_prefs(DEVICE_NAME)
+
+    state_updates: list[aioesphomeapi.ClimateState] = []
+    on_control_count = 0
+
+    def on_log_line(line: str) -> None:
+        nonlocal on_control_count
+        if "on_control fired" in line:
+            on_control_count += 1
+
+    async with (
+        run_compiled(yaml_config, line_callback=on_log_line),
+        api_client_connected() as client,
+    ):
+
+        def on_state(state: aioesphomeapi.EntityState) -> None:
+            if isinstance(state, aioesphomeapi.ClimateState):
+                state_updates.append(state)
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        climate_infos = [e for e in entities if isinstance(e, ClimateInfo)]
+        assert len(climate_infos) == 1, "Expected exactly 1 climate entity"
+
+        publish_button = require_entity(entities, "publish_all", ButtonInfo)
+
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+        try:
+            await initial_state_helper.wait_for_initial_states()
+        except TimeoutError:
+            pytest.fail("Timeout waiting for initial states")
+
+        client.button_command(publish_button.key)
+        try:
+            state = await wait_for_state(
+                client, lambda s: isinstance(s, aioesphomeapi.ClimateState)
+            )
+        except TimeoutError:
+            pytest.fail("Timeout waiting for the published climate state")
+
+        assert state.current_temperature == pytest.approx(20.0, abs=0.1)
+        assert state.current_humidity == pytest.approx(60.0, abs=0.1)
+        assert state.target_temperature == pytest.approx(23.0, abs=0.1)
+        assert state.mode == ClimateMode.HEAT
+        assert state.action == ClimateAction.HEATING
+        assert state.fan_mode == ClimateFanMode.HIGH
+        assert state.swing_mode == ClimateSwingMode.VERTICAL
+        assert state.preset == ClimatePreset.ECO
+
+        # Give any stray extra update (there shouldn't be one) a moment to arrive.
+        await asyncio.sleep(0.2)
+        assert len(state_updates) == 1, (
+            f"Expected exactly one ClimateState update, got {len(state_updates)}"
+        )
+        assert on_control_count == 0, (
+            "climate.template.publish must not trigger on_control"
+        )

tests/integration/test_template_climate_sensor_push.py

@@ -0,0 +1,88 @@
+"""Integration test for template climate: current_temperature/current_humidity live sensor push.
+
+A *later* change to a backing sensor's value -- not just its initial reading at boot -- propagates
+into a new climate state via add_on_state_callback. Re-publishing the same sensor value again must
+not cause a redundant climate state update.
+"""
+
+from __future__ import annotations
+
+import asyncio
+import math
+
+import aioesphomeapi
+from aioesphomeapi import ButtonInfo, ClimateInfo
+import pytest
+
+from .host_prefs import clear_host_prefs
+from .state_utils import InitialStateHelper, require_entity, wait_for_state
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+DEVICE_NAME = "tmpl-clim-sensor-push"
+
+
+@pytest.mark.asyncio
+async def test_template_climate_sensor_push(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """A later change to the backing sensor pushes a new climate state; an unchanged republish does not."""
+    clear_host_prefs(DEVICE_NAME)
+
+    state_updates: list[aioesphomeapi.ClimateState] = []
+
+    async with (
+        run_compiled(yaml_config),
+        api_client_connected() as client,
+    ):
+
+        def on_state(state: aioesphomeapi.EntityState) -> None:
+            if isinstance(state, aioesphomeapi.ClimateState):
+                state_updates.append(state)
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        climate_infos = [e for e in entities if isinstance(e, ClimateInfo)]
+        assert len(climate_infos) == 1, "Expected exactly 1 climate entity"
+        test_climate = climate_infos[0]
+
+        publish_temp = require_entity(entities, "publish_temperature", ButtonInfo)
+        publish_temp_same = require_entity(
+            entities, "publish_temperature_same", ButtonInfo
+        )
+        publish_humidity = require_entity(entities, "publish_humidity", ButtonInfo)
+
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+        try:
+            await initial_state_helper.wait_for_initial_states()
+        except TimeoutError:
+            pytest.fail("Timeout waiting for initial states")
+
+        initial = initial_state_helper.initial_states.get(test_climate.key)
+        assert initial is not None, "No initial climate state received"
+        assert isinstance(initial, aioesphomeapi.ClimateState)
+        # Neither backing sensor has published anything yet.
+        assert math.isnan(initial.current_temperature)
+        assert math.isnan(initial.current_humidity)
+
+        # A later sensor reading -- not the initial one -- pushes a new climate state.
+        client.button_command(publish_temp.key)
+        state = await wait_for_state(
+            client, lambda s: isinstance(s, aioesphomeapi.ClimateState)
+        )
+        assert state.current_temperature == pytest.approx(24.0, abs=0.1)
+
+        client.button_command(publish_humidity.key)
+        state = await wait_for_state(
+            client, lambda s: isinstance(s, aioesphomeapi.ClimateState)
+        )
+        assert state.current_humidity == pytest.approx(65.0, abs=0.1)
+
+        # Re-publishing the same temperature must not cause a redundant climate state update.
+        updates_before = len(state_updates)
+        client.button_command(publish_temp_same.key)
+        await asyncio.sleep(0.3)
+        assert len(state_updates) == updates_before, (
+            "Re-publishing an unchanged sensor reading must not republish the climate state"
+        )

tests/integration/test_template_climate_set_actions.py

@@ -0,0 +1,114 @@
+"""Integration test: each settable field forwards its value to the matching set_*_action.
+
+With optimistic: false the entity state stays put until climate.template.publish reports the
+device's actual state back, so the actions are the only thing that reacts to a command.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import aioesphomeapi
+from aioesphomeapi import (
+    ButtonInfo,
+    ClimateFanMode,
+    ClimateInfo,
+    ClimateMode,
+    ClimatePreset,
+    ClimateSwingMode,
+)
+import pytest
+
+from .host_prefs import clear_host_prefs
+from .state_utils import InitialStateHelper, require_entity, wait_for_state
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+DEVICE_NAME = "tmpl-clim-set-act"
+
+
+@pytest.mark.asyncio
+async def test_template_climate_set_actions(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Every set_*_action fires with the requested value; state waits for a publish."""
+    clear_host_prefs(DEVICE_NAME)
+
+    log_lines: list[str] = []
+
+    def on_log_line(line: str) -> None:
+        if "_action " in line or "Unsupported" in line:
+            log_lines.append(line)
+
+    def logged(fragment: str) -> bool:
+        return any(fragment in line for line in log_lines)
+
+    async with (
+        run_compiled(yaml_config, line_callback=on_log_line),
+        api_client_connected() as client,
+    ):
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        climate_infos = [e for e in entities if isinstance(e, ClimateInfo)]
+        assert len(climate_infos) == 1, "Expected exactly 1 climate entity"
+        test_climate = climate_infos[0]
+
+        report_button = require_entity(entities, "report_device_state", ButtonInfo)
+        unsupported_button = require_entity(
+            entities, "report_unsupported_mode", ButtonInfo
+        )
+
+        client.subscribe_states(
+            initial_state_helper.on_state_wrapper(lambda state: None)
+        )
+        try:
+            await initial_state_helper.wait_for_initial_states()
+        except TimeoutError:
+            pytest.fail("Timeout waiting for initial states")
+
+        # Both traits are derived from the low/high and humidity set actions, not declared.
+        assert test_climate.supports_two_point_target_temperature
+        assert test_climate.supports_target_humidity
+
+        client.climate_command(test_climate.key, mode=ClimateMode.HEAT)
+        client.climate_command(
+            test_climate.key, target_temperature_low=18.0, target_temperature_high=24.0
+        )
+        client.climate_command(test_climate.key, target_humidity=55)
+        client.climate_command(test_climate.key, fan_mode=ClimateFanMode.LOW)
+        client.climate_command(test_climate.key, custom_fan_mode="turbo")
+        client.climate_command(test_climate.key, swing_mode=ClimateSwingMode.VERTICAL)
+        client.climate_command(test_climate.key, preset=ClimatePreset.ECO)
+        client.climate_command(test_climate.key, custom_preset="eco_plus")
+
+        for _ in range(50):
+            await asyncio.sleep(0.1)
+            if logged("set_custom_preset_action eco_plus"):
+                break
+
+        assert logged("set_mode_action 3")  # CLIMATE_MODE_HEAT
+        assert logged("set_target_temperature_low_action 18.0")
+        assert logged("set_target_temperature_high_action 24.0")
+        assert logged("set_target_humidity_action 55")
+        assert logged("set_fan_mode_action 3")  # CLIMATE_FAN_LOW
+        assert logged("set_custom_fan_mode_action turbo")
+        assert logged("set_swing_mode_action 2")  # CLIMATE_SWING_VERTICAL
+        assert logged("set_preset_action 5")  # CLIMATE_PRESET_ECO
+        assert logged("set_custom_preset_action eco_plus")
+
+        # optimistic: false, so none of the commands above touched the entity's own state --
+        # a device report is what actually moves it.
+        client.button_command(report_button.key)
+        state = await wait_for_state(
+            client, lambda s: isinstance(s, aioesphomeapi.ClimateState)
+        )
+        assert state.mode == ClimateMode.HEAT
+
+        # A publish naming a mode outside supported_modes warns instead of publishing it.
+        client.button_command(unsupported_button.key)
+        for _ in range(50):
+            await asyncio.sleep(0.1)
+            if logged("Unsupported mode"):
+                break
+        assert logged("Unsupported mode")

tests/integration/test_template_climate_two_point_temperature.py

@@ -0,0 +1,118 @@
+"""Integration tests for template climate: two-point target temperature + humidity.
+
+Covers the supports_two_point_target_temperature/supports_target_humidity boolean flags plus
+on_control (forwarding commands out) and climate.template.publish (the device reporting its own
+authoritative state, independent of any prior command -- e.g. a device that owns its own setpoint,
+changed via a physical remote).
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import aioesphomeapi
+from aioesphomeapi import ButtonInfo, ClimateInfo, ClimateMode
+import pytest
+
+from .host_prefs import clear_host_prefs
+from .state_utils import InitialStateHelper, require_entity, wait_for_state
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+DEVICE_NAME = "tmpl-clim-two-point"
+
+
+@pytest.mark.asyncio
+async def test_template_climate_two_point_temperature(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Two-point target temperature + humidity: booleans, on_control, and publish precedence."""
+    clear_host_prefs(DEVICE_NAME)
+
+    log_lines: list[str] = []
+
+    def on_log_line(line: str) -> None:
+        if "on_control " in line:
+            log_lines.append(line)
+
+    async with (
+        run_compiled(yaml_config, line_callback=on_log_line),
+        api_client_connected() as client,
+    ):
+
+        async def wait_for_climate_state(
+            timeout: float = 5.0,
+        ) -> aioesphomeapi.ClimateState:
+            return await wait_for_state(
+                client, lambda s: isinstance(s, aioesphomeapi.ClimateState), timeout
+            )
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        climate_infos = [e for e in entities if isinstance(e, ClimateInfo)]
+        assert len(climate_infos) == 1, "Expected exactly 1 climate entity"
+
+        test_climate = climate_infos[0]
+        assert test_climate.name == "Test Two-Point Heatpump"
+        assert test_climate.supports_two_point_target_temperature
+        assert test_climate.supports_target_humidity
+
+        report_button = require_entity(entities, "simulate_device_report", ButtonInfo)
+
+        client.subscribe_states(
+            initial_state_helper.on_state_wrapper(lambda state: None)
+        )
+
+        try:
+            await initial_state_helper.wait_for_initial_states()
+        except TimeoutError:
+            pytest.fail("Timeout waiting for initial states")
+
+        initial = initial_state_helper.initial_states.get(test_climate.key)
+        assert initial is not None, "No initial climate state received"
+        assert isinstance(initial, aioesphomeapi.ClimateState)
+        # Nothing has been published yet: settable fields have no sensor to seed them from, so
+        # the entity starts at ESPHome's plain defaults. current_temperature is pushed by the
+        # referenced sensor, which has already settled by the time we get here.
+        assert initial.mode == ClimateMode.OFF
+        assert initial.current_temperature == pytest.approx(21.0, abs=0.1)
+
+        # The device reports its actual state for the first time.
+        client.button_command(report_button.key)
+        state = await wait_for_climate_state()
+        assert state.mode == ClimateMode.HEAT_COOL
+        assert state.target_temperature_low == pytest.approx(18.0, abs=0.1)
+        assert state.target_temperature_high == pytest.approx(24.0, abs=0.1)
+        assert state.target_humidity == pytest.approx(50.0, abs=0.1)
+
+        # Commands apply optimistically (settable fields are plain internal state), and on_control
+        # fires with the same values so a real config could forward them to the device.
+        client.climate_command(
+            test_climate.key, target_temperature_low=19.0, target_temperature_high=25.0
+        )
+        state = await wait_for_climate_state()
+        assert state.target_temperature_low == pytest.approx(19.0, abs=0.1)
+        assert state.target_temperature_high == pytest.approx(25.0, abs=0.1)
+        await asyncio.sleep(0.2)
+        assert any(
+            "on_control target_temperature_low=19.0" in line for line in log_lines
+        )
+        assert any(
+            "on_control target_temperature_high=25.0" in line for line in log_lines
+        )
+
+        client.climate_command(test_climate.key, target_humidity=45.0)
+        state = await wait_for_climate_state()
+        assert state.target_humidity == pytest.approx(45.0, abs=0.1)
+        await asyncio.sleep(0.2)
+        assert any("on_control target_humidity=45.0" in line for line in log_lines)
+
+        # The device's next report is authoritative and overrides whatever was optimistically
+        # applied above -- this is the whole point of climate.template.publish: a device that owns
+        # its own state (e.g. changed by a physical remote) always wins.
+        client.button_command(report_button.key)
+        state = await wait_for_climate_state()
+        assert state.target_temperature_low == pytest.approx(18.0, abs=0.1)
+        assert state.target_temperature_high == pytest.approx(24.0, abs=0.1)
+        assert state.target_humidity == pytest.approx(50.0, abs=0.1)

tests/integration/test_uart_mock_modbus.py

@@ -173,6 +173,7 @@ async def test_uart_mock_modbus_no_threshold(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_server_injected")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_server(
     yaml_config: str,
@@ -203,6 +204,7 @@ async def test_uart_mock_modbus_server(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_server_injected")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_server_read_write(
     yaml_config: str,
@@ -231,8 +233,8 @@ async def test_uart_mock_modbus_server_read_write(
             "rw_write_1": 4660,  # 0x1234 written to reg 0x0001
             "rw_read_1": 4660,  # reg 0x0001 reads back the just-written value
             "rw_read_2": 170,  # 0x00AA read from reg 0x0002 in the same request
-            "rw_write_3": 22136,  # 0x5678 written to reg 0x0003
-            "rw_read_3": 22136,  # reg 0x0003 reads back the just-written value
+            "rw_write_3": 22136,  # 0x5678 written to reg 0x0006
+            "rw_read_3": 22136,  # reg 0x0006 reads back the just-written value
         }
     )
 
@@ -241,7 +243,8 @@ async def test_uart_mock_modbus_server_read_write(
         api_client_connected() as client,
     ):
         await tracker.setup_and_start_scenario(client)
-        await tracker.await_all(futures)
+        # The FC 0x17 injections fire last, behind four earlier 100ms delays
+        await tracker.await_all(futures, timeout=4.0)
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
@@ -296,6 +299,7 @@ async def test_uart_mock_modbus_server_read_write_invalid(
     )
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_mesh")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_server_controller(
     yaml_config: str,
@@ -485,6 +489,7 @@ async def test_uart_mock_modbus_server_controller_bits(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_mesh")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_server_controller_multiple(
     yaml_config: str,
@@ -495,7 +500,7 @@ async def test_uart_mock_modbus_server_controller_multiple(
 
     line_callback, error_log_lines, warning_log_lines = _make_modbus_line_callback()
 
-    expected_values = {"reg_u_word": 919, "reg_u_word_2": 929}
+    expected_values = {"multi_reg_a": 919, "multi_reg_b": 929}
     tracker = SensorTracker(list(expected_values.keys()))
     futures = tracker.expect_all(expected_values)
 
@@ -706,6 +711,7 @@ async def test_uart_mock_modbus_shared_address(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_loopback")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_custom_pdu(
     yaml_config: str,
@@ -932,6 +938,7 @@ async def test_uart_mock_modbus_broadcast_write(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_mesh")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_client_read_write(
     yaml_config: str,
@@ -947,9 +954,7 @@ async def test_uart_mock_modbus_client_read_write(
     """
     line_callback, error_log_lines, warning_log_lines = _make_modbus_line_callback()
 
-    tracker = SensorTracker(
-        ["srv_write_1", "srv_read_1", "client_read_0", "client_read_1"]
-    )
+    tracker = SensorTracker(["srv_write_1", "client_read_0", "client_read_1"])
     futures = tracker.expect_all(
         {
             "srv_write_1": 4660,  # server wrote 0x1234 to reg 0x0001
@@ -967,6 +972,7 @@ async def test_uart_mock_modbus_client_read_write(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_loopback")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_register_offset(
     yaml_config: str,
@@ -1022,6 +1028,7 @@ async def test_uart_mock_modbus_register_offset(
         )
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_loopback")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_lambda_write(
     yaml_config: str,
@@ -1058,6 +1065,7 @@ async def test_uart_mock_modbus_lambda_write(
         await tracker.await_change(wrote_30, "reg_30", timeout=4.0)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_loopback")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_lambda_invert(
     yaml_config: str,
@@ -1113,6 +1121,7 @@ async def test_uart_mock_modbus_lambda_invert(
         )
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_loopback")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_deprecated_write_buffer(
     yaml_config: str,

tests/script/test_helpers.py

@@ -2122,6 +2122,34 @@ def test_get_cpp_changed_components_independent_of_cwd(
     ) == ["time"]
 
 
+def test_fixture_map_includes_shared_yaml_markers() -> None:
+    """Fixtures named only by shared_yaml markers must map to their test file."""
+    helpers.get_fixture_to_test_files.cache_clear()
+    mapping = helpers.get_fixture_to_test_files()
+    for fixture in (
+        "uart_mock_modbus_loopback",
+        "uart_mock_modbus_mesh",
+        "uart_mock_modbus_server_injected",
+    ):
+        assert mapping[fixture] == frozenset(
+            {"tests/integration/test_uart_mock_modbus.py"}
+        )
+
+
+def test_no_orphan_integration_fixtures() -> None:
+    """Every fixture must reach CI test selection; an orphan selects nothing."""
+    helpers.get_fixture_to_test_files.cache_clear()
+    mapping = helpers.get_fixture_to_test_files()
+    fixtures_dir = (Path(__file__).parent.parent / "integration" / "fixtures").resolve()
+    fixtures = list(fixtures_dir.glob("*.yaml"))
+    assert fixtures, f"no fixtures found under {fixtures_dir}"
+    # cache_init is covered via INTEGRATION_TESTS_TRIGGER_FILES instead
+    orphans = [
+        f.stem for f in fixtures if f.stem != "cache_init" and f.stem not in mapping
+    ]
+    assert not orphans, f"fixtures invisible to CI test selection: {orphans}"
+
+
 def test_lpt_partition_balances_skewed_weights() -> None:
     """Heavy items spread across groups instead of clustering."""
     items = [f"i{n}" for n in range(6)]

tests/script/test_platformio_install_deps.py

@@ -35,8 +35,8 @@ def _load_script():
 def test_spec_key_collapses_destinations() -> None:
     """Two specs delivering one package share a directory and one key."""
     mod = _load_script()
-    assert mod.spec_key("esphome/noise-c @ 0.1.21") == "noise-c"
-    assert mod.spec_key("esphome/noise-c@0.1.21") == "noise-c"
+    assert mod.spec_key("esphome/noise-c @ 0.1.24") == "noise-c"
+    assert mod.spec_key("esphome/noise-c@0.1.24") == "noise-c"
     assert mod.spec_key("ESP32Async/AsyncTCP @ ^3.4.10") == mod.spec_key(
         "esp32async/asynctcp @ 3.5.0"
     )
@@ -54,23 +54,23 @@ def test_parse_specs_and_cli_args(tmp_path: Path) -> None:
         "[env:a]\n"
         "platform = fake/platform@1\n"
         "lib_deps =\n"
-        "    esphome/noise-c @ 0.1.21\n"
+        "    esphome/noise-c @ 0.1.24\n"
         "    ${common.lib_deps}\n"
         "    internal_lib\n"
         "[env:b]\n"
         "lib_deps =\n"
-        "    esphome/noise-c @ 0.1.21\n"
+        "    esphome/noise-c @ 0.1.24\n"
     )
     mod = _load_script()
     args = Namespace(libraries=True, platforms=True, tools=False)
     libs, platforms, tools = mod.parse_specs(str(ini), args)
     # exact-string duplicates collapse; distinct version pins survive
-    assert libs == ["esphome/noise-c @ 0.1.21"]
+    assert libs == ["esphome/noise-c @ 0.1.24"]
     assert platforms == ["fake/platform@1"]
     assert tools == []
     assert mod.build_cli_args(libs, platforms, tools) == [
         "-l",
-        "esphome/noise-c @ 0.1.21",
+        "esphome/noise-c @ 0.1.24",
         "-p",
         "fake/platform@1",
     ]
@@ -162,13 +162,13 @@ def test_parallel_install_behavior(tmp_path: Path) -> None:
     mod.parallel_install(
         cls,
         [
-            "esphome/noise-c @ 0.1.21",
-            "esphome/noise-c @ 0.1.21",
+            "esphome/noise-c @ 0.1.24",
+            "esphome/noise-c @ 0.1.24",
             "esphome/already @ 1.0",
             "https://x/framework.tar.xz",
         ],
     )
-    assert cls.calls == ["esphome/noise-c @ 0.1.21"]
+    assert cls.calls == ["esphome/noise-c @ 0.1.24"]
     assert cls.lock_events == ["lock", "unlock"]
 
 
@@ -205,7 +205,7 @@ def test_parallel_install_runs_dependency_waves(tmp_path: Path) -> None:
     mod = _load_script()
     cls = _reset_fake(str(tmp_path))
     cls.deps = {
-        "esphome/noise-c @ 0.1.21": [
+        "esphome/noise-c @ 0.1.24": [
             {"owner": "esphome", "name": "libsodium", "version": "^1.0"},
             {"name": "SPI"},
         ],
@@ -213,12 +213,12 @@ def test_parallel_install_runs_dependency_waves(tmp_path: Path) -> None:
             {"owner": "esphome", "name": "libsodium", "version": "^1.0"},
         ],
     }
-    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.21", "esphome/wg @ 1.0"])
+    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.24", "esphome/wg @ 1.0"])
     assert len(cls.calls) == 3  # the shared dep installs exactly once
     assert {mod.spec_key(c) for c in cls.calls} == {"noise-c", "wg", "libsodium"}
     # Wave-1 strings carry no compatibility; the dependency wave does
     compats = dict(cls.compat_calls)
-    assert compats["esphome/noise-c @ 0.1.21"] is None
+    assert compats["esphome/noise-c @ 0.1.24"] is None
     dep_compat = next(v for k, v in cls.compat_calls if "libsodium" in k)
     assert dep_compat is not None  # mirrors pio's install_dependency
 
@@ -229,11 +229,11 @@ def test_dependency_wave_excludes_url_specs(tmp_path: Path) -> None:
     mod = _load_script()
     cls = _reset_fake(str(tmp_path))
     cls.deps = {
-        "esphome/noise-c @ 0.1.21": [
+        "esphome/noise-c @ 0.1.24": [
             {"name": "vendored", "version": "https://github.com/x/y.git"},
         ],
     }
-    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.21"])
+    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.24"])
     assert {mod.spec_key(c) for c in cls.calls} == {"noise-c"}
 
 
@@ -348,13 +348,13 @@ def test_warm_store_still_walks_dependencies(tmp_path: Path) -> None:
     """Already-installed top-level packages still feed the dependency
     wave; a warm store can be missing a transitive dep."""
     mod = _load_script()
-    cls = _reset_fake(str(tmp_path), installed={"esphome/noise-c @ 0.1.21"})
+    cls = _reset_fake(str(tmp_path), installed={"esphome/noise-c @ 0.1.24"})
     cls.deps = {
-        "esphome/noise-c @ 0.1.21": [
+        "esphome/noise-c @ 0.1.24": [
             {"owner": "esphome", "name": "libsodium", "version": "^1.0"},
         ],
     }
-    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.21"])
+    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.24"])
     assert [mod.spec_key(c) for c in cls.calls] == ["libsodium"]