Merge branch 'esp8266-native-build-surgery' into esp8266-native-toolchain-plumbing

tests/component_tests/modbus_controller/test_custom_pdu.py

@@ -1,19 +1,27 @@
-"""Schema-level config validation for custom_pdu and the deprecated custom_command alias.
+"""Config validation for custom_pdu and the deprecated custom_command alias.
 
 custom_command took a raw frame with a leading device address byte; custom_pdu takes the PDU only.
-The old key is still accepted at the schema level and auto-migrated later in final validate (which a
-bare-schema test can't reach), so these tests only cover what the schema itself enforces: the two keys
-are mutually exclusive, and custom_pdu takes byte-sized values.
+Most of these tests cover what the schema itself enforces (the two keys are mutually exclusive, and
+custom_pdu takes byte-sized values). The last two reach the final-validate step that a bare-schema
+test cannot: a write-coded custom_pdu polled continuously is rejected there.
 """
 
 import pytest
 from voluptuous import Invalid, MultipleInvalid
 
-from esphome.components.modbus_controller import ModbusItemBaseSchema
+from esphome.components.modbus_controller import (
+    ModbusItemBaseSchema,
+    validate_custom_pdu_item,
+)
 from esphome.components.modbus_controller.const import (
     CONF_CUSTOM_COMMAND,
     CONF_CUSTOM_PDU,
+    CONF_MODBUS_CONTROLLER_ID,
 )
+from esphome.config import Config
+from esphome.const import CONF_ADDRESS, CONF_CONTINUOUS, CONF_ID
+from esphome.core import ID
+import esphome.final_validate as fv
 
 
 def test_custom_command_accepted_at_schema_level() -> None:
@@ -45,3 +53,48 @@ def test_custom_pdu_rejects_non_byte_values() -> None:
     """PDU entries are bytes; a word-sized value is a sign the old raw format is being used."""
     with pytest.raises((Invalid, MultipleInvalid)):
         ModbusItemBaseSchema({CONF_CUSTOM_PDU: [0x0103, 0x002A]})
+
+
+def _controller_full_config(*, continuous: bool) -> Config:
+    """A minimal full-config graph with one modbus_controller declaring id 'ctl', enough for the
+    final-validate to resolve the controller (and its continuous flag) from an item's
+    modbus_controller_id."""
+    ctl_id = ID("ctl", is_declaration=True)
+    config = Config()
+    config["modbus_controller"] = [
+        {CONF_ID: ctl_id, CONF_ADDRESS: 1, CONF_CONTINUOUS: continuous}
+    ]
+    config.declare_ids.append((ctl_id, ["modbus_controller", 0, CONF_ID]))
+    return config
+
+
+@pytest.fixture
+def reset_full_config():
+    token = fv.full_config.set(Config())
+    yield
+    fv.full_config.reset(token)
+
+
+def test_continuous_write_custom_pdu_rejected(reset_full_config) -> None:
+    """A write-coded custom_pdu (0x17 = read/write-multiple) under a continuous controller is
+    rejected at final validate: the hub would strip continuous from the mutating code and warn on
+    every update."""
+    fv.full_config.set(_controller_full_config(continuous=True))
+    with pytest.raises(Invalid, match="can't be polled continuously"):
+        validate_custom_pdu_item(
+            {
+                CONF_MODBUS_CONTROLLER_ID: ID("ctl"),
+                CONF_CUSTOM_PDU: [0x17, 0x00, 0x03, 0x00, 0x01],
+            }
+        )
+
+
+def test_continuous_read_custom_pdu_allowed(reset_full_config) -> None:
+    """A read-coded custom_pdu (0x03) under a continuous controller is fine - only writes stream."""
+    fv.full_config.set(_controller_full_config(continuous=True))
+    validate_custom_pdu_item(
+        {
+            CONF_MODBUS_CONTROLLER_ID: ID("ctl"),
+            CONF_CUSTOM_PDU: [0x03, 0x00, 0x2A, 0x00, 0x01],
+        }
+    )

tests/components/audio_http/common.yaml

@@ -4,4 +4,5 @@ media_source:
   - platform: audio_http
     id: audio_http_source
     buffer_size: 100000
+    persistent_ring_buffer: true
     task_stack_in_psram: true

tests/components/mitsubishi_cn105/climate/mitsubishi_cn105_climate_tests.cpp

@@ -15,11 +15,10 @@ struct MitsubishiCN105ClimateTestContext {
 
 TEST(MitsubishiCN105ClimateTests, CelsiusTemperatureMappingAndTraitsMatchExpectedValues) {
   MitsubishiCN105ClimateTestContext context;
-  const auto mapping = TemperatureMapping();
 
   for (int temperature = 16; temperature <= 31; ++temperature) {
-    EXPECT_EQ(mapping.to_mitsubishi(temperature), temperature);
-    EXPECT_EQ(mapping.from_mitsubishi(temperature), temperature);
+    EXPECT_EQ(context.component.get_temperature_mapping().to_mitsubishi(temperature), temperature);
+    EXPECT_EQ(context.component.get_temperature_mapping().from_mitsubishi(temperature), temperature);
   }
 
   const auto traits = context.sut.traits();
@@ -32,8 +31,6 @@ TEST(MitsubishiCN105ClimateTests, CelsiusTemperatureMappingAndTraitsMatchExpecte
 
 TEST(MitsubishiCN105ClimateTests, FahrenheitTemperatureMappingAndTraitsMatchExpectedValues) {
   MitsubishiCN105ClimateTestContext context;
-  auto mapping = TemperatureMapping();
-  mapping.set_use_fahrenheit(true);
   context.component.set_use_fahrenheit(true);
 
   const std::array cases{
@@ -46,8 +43,8 @@ TEST(MitsubishiCN105ClimateTests, FahrenheitTemperatureMappingAndTraitsMatchExpe
   };
 
   for (const auto &[fahrenheit, mitsubishi_celsius] : cases) {
-    EXPECT_FLOAT_EQ(mapping.to_mitsubishi(fahrenheit), mitsubishi_celsius);
-    EXPECT_FLOAT_EQ(mapping.from_mitsubishi(mitsubishi_celsius), fahrenheit);
+    EXPECT_FLOAT_EQ(context.component.get_temperature_mapping().to_mitsubishi(fahrenheit), mitsubishi_celsius);
+    EXPECT_FLOAT_EQ(context.component.get_temperature_mapping().from_mitsubishi(mitsubishi_celsius), fahrenheit);
   }
   const auto traits = context.sut.traits();
   EXPECT_EQ(traits.get_temperature_unit(), TemperatureUnit::FAHRENHEIT);

tests/components/mitsubishi_cn105/climate/mitsubishi_cn105_tests.cpp

@@ -42,11 +42,17 @@ TEST(MitsubishiCN105Tests, ConnectAndUpdateStatus) {
 
   // All bytes from UART should be consumed
   EXPECT_TRUE(ctx.uart.rx.empty());
-  // After successful connect we request status, first settings (0x02)
+  // Defer the first settings request (0x02) until the next update.
+  EXPECT_EQ(ctx.sut.state_, TestableMitsubishiCN105::State::DEFERRED_STATUS_REQUEST);
+  EXPECT_TRUE(ctx.uart.tx.empty());
+
+  ctx.sut.set_current_time(201);
+  ASSERT_FALSE(ctx.sut.update());
+
   EXPECT_EQ(ctx.sut.state_, TestableMitsubishiCN105::State::UPDATING_STATUS);
   EXPECT_THAT(ctx.uart.tx, ::testing::ElementsAre(0xFC, 0x42, 0x01, 0x30, 0x10, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00,
                                                   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x7B));
-  EXPECT_EQ(ctx.sut.operation_start_ms_, 200);
+  EXPECT_EQ(ctx.sut.operation_start_ms_, 201);
 
   // Clear TX bytes.
   ctx.uart.tx.clear();
@@ -75,15 +81,24 @@ TEST(MitsubishiCN105Tests, ConnectAndUpdateStatus) {
   EXPECT_EQ(ctx.sut.status().vane_mode, MitsubishiCN105::VaneMode::POSITION_4);
   EXPECT_EQ(ctx.sut.status().wide_vane_mode, MitsubishiCN105::WideVaneMode::SWING);
 
-  // Now fetch telemetry (0x03)
+  // Defer the telemetry request (0x03) until the next update.
+  EXPECT_EQ(ctx.sut.state_, TestableMitsubishiCN105::State::DEFERRED_STATUS_REQUEST);
+  EXPECT_TRUE(ctx.uart.tx.empty());
+
+  ctx.sut.set_current_time(301);
+  ASSERT_FALSE(ctx.sut.update());
+
   EXPECT_EQ(ctx.sut.state_, TestableMitsubishiCN105::State::UPDATING_STATUS);
   EXPECT_THAT(ctx.uart.tx, ::testing::ElementsAre(0xFC, 0x42, 0x01, 0x30, 0x10, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00,
                                                   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x7A));
-  EXPECT_EQ(ctx.sut.operation_start_ms_, 300);
+  EXPECT_EQ(ctx.sut.operation_start_ms_, 301);
 
   // Clear TX bytes.
   ctx.uart.tx.clear();
 
+  // Queue a setting while waiting for telemetry.
+  ctx.sut.set_power(true);
+
   // Telemetry response
   ctx.uart.push_rx({0xFC, 0x62, 0x01, 0x30, 0x10, 0x03, 0x00, 0x00, 0x0B, 0x00, 0x00,
                     0xAA, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xA5});
@@ -103,6 +118,13 @@ TEST(MitsubishiCN105Tests, ConnectAndUpdateStatus) {
   EXPECT_TRUE(ctx.uart.tx.empty());
   EXPECT_EQ(ctx.sut.state_, TestableMitsubishiCN105::State::WAITING_FOR_SCHEDULED_STATUS_UPDATE);
   EXPECT_EQ(ctx.sut.operation_start_ms_, 400);
+
+  // Apply the pending setting on the next update, outside RX processing.
+  ctx.sut.set_current_time(401);
+  ASSERT_FALSE(ctx.sut.update());
+  EXPECT_EQ(ctx.sut.state_, TestableMitsubishiCN105::State::APPLYING_SETTINGS);
+  EXPECT_FALSE(ctx.uart.tx.empty());
+  EXPECT_EQ(ctx.sut.operation_start_ms_, 401);
 }
 
 TEST(MitsubishiCN105Tests, NoResponseTriggersReconnect) {
@@ -469,6 +491,36 @@ TEST(MitsubishiCN105Tests, WriteInterruptsWaitingForNextStatusUpdate) {
   EXPECT_EQ(ctx.sut.status_update_wait_credit_ms_, 0);
 }
 
+TEST(MitsubishiCN105Tests, PendingSettingsTakePriorityOverDueTelemetry) {
+  MitsubishiCN105TestsContext ctx;
+
+  ctx.sut.status_.target_temperature = 24.0f;
+  ctx.sut.status_.room_temperature = 21.0f;
+  ASSERT_TRUE(ctx.sut.is_status_initialized());
+
+  ctx.sut.state_ = TestableMitsubishiCN105::State::STATUS_UPDATED;
+  ctx.sut.set_state(TestableMitsubishiCN105::State::SCHEDULE_NEXT_STATUS_UPDATE);
+  ctx.sut.set_current_time(1000);
+  ASSERT_FALSE(ctx.sut.update());
+  ASSERT_EQ(ctx.sut.state_, TestableMitsubishiCN105::State::UPDATING_STATUS);
+  ctx.uart.tx.clear();
+
+  ctx.sut.set_power(true);
+  ctx.uart.push_rx({0xFC, 0x62, 0x01, 0x30, 0x10, 0x02, 0x00, 0x00, 0x00, 0x08, 0x07,
+                    0x00, 0x04, 0x00, 0x00, 0x0C, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3C});
+
+  ctx.sut.set_current_time(1001);
+  ASSERT_TRUE(ctx.sut.update());
+  EXPECT_TRUE(ctx.uart.tx.empty());
+  EXPECT_EQ(ctx.sut.state_, TestableMitsubishiCN105::State::WAITING_FOR_SCHEDULED_STATUS_UPDATE);
+
+  ctx.sut.set_current_time(1002);
+  ASSERT_FALSE(ctx.sut.update());
+  EXPECT_EQ(ctx.sut.state_, TestableMitsubishiCN105::State::APPLYING_SETTINGS);
+  EXPECT_THAT(ctx.uart.tx, ::testing::ElementsAre(0xFC, 0x41, 0x01, 0x30, 0x10, 0x01, 0x01, 0x00, 0x01, 0x00, 0x00,
+                                                  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x7B));
+}
+
 TEST(MitsubishiCN105Tests, SetAndClearRemoteRoomTemp) {
   MitsubishiCN105TestsContext ctx;
 

tests/components/modbus_controller/common.yaml

@@ -2,6 +2,7 @@ modbus_controller:
   - id: modbus_controller1
     address: 0x2
     modbus_id: modbus_bus
+    continuous: true
     on_online:
       then:
         logger.log: "Module Online"

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

@@ -1,2 +1,9 @@
 preferences:
+  id: prefs_syncer
   flash_write_interval: 20s
+
+esphome:
+  on_boot:
+    then:
+      - component.suspend: prefs_syncer
+      - component.resume: prefs_syncer

tests/integration/fixtures/host_preferences_suspend_resume.yaml

@@ -0,0 +1,41 @@
+esphome:
+  name: test_suspend_resume_device
+
+host:
+
+logger:
+  level: DEBUG
+
+api:
+
+preferences:
+  id: prefs_syncer
+  flash_write_interval: 1s
+
+button:
+  - platform: template
+    name: "Save Preference"
+    on_press:
+      - lambda: |-
+          // save() only updates the in-memory map; only sync() persists it to disk.
+          ESPPreferenceObject pref = global_preferences->make_preference<uint32_t>(0xBEEF);
+          uint32_t value = 123;
+          if (pref.save(&value)) {
+            ESP_LOGI("test", "Preference saved in memory");
+          } else {
+            ESP_LOGE("test", "Preference save failed");
+          }
+
+  - platform: template
+    name: "Suspend Syncer"
+    on_press:
+      - component.suspend: prefs_syncer
+      - lambda: |-
+          ESP_LOGI("test", "Syncer suspended");
+
+  - platform: template
+    name: "Resume Syncer"
+    on_press:
+      - component.resume: prefs_syncer
+      - lambda: |-
+          ESP_LOGI("test", "Syncer resumed");

tests/integration/fixtures/uart_mock_modbus_continuous.yaml

@@ -0,0 +1,115 @@
+esphome:
+  name: uart-mock-modbus-continuous
+
+host:
+api:
+logger:
+  level: VERBOSE
+
+# When set, the mock server stops forwarding its replies to the controller, so the controller sees
+# timeouts - used by the recovery test to drive a live continuous poll offline and back.
+globals:
+  - id: silence_server
+    type: bool
+    initial_value: "false"
+
+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:
+          - if:
+              condition:
+                lambda: "return !id(silence_server);"
+              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
+    # Short timeout so the recovery test drives the poll offline quickly; when the server answers,
+    # replies arrive within turnaround_time, so this does not slow the streaming path.
+    send_wait_time: 100ms
+
+modbus_controller:
+  - address: 1
+    modbus_id: virtual_modbus_controller
+    id: modbus_controller_1
+    # A long update_interval means that without continuous polling only the boot poll would run in the
+    # test window. continuous: true re-queues the read after each success, so it streams as fast as the
+    # bus allows.
+    update_interval: 30s
+    continuous: true
+    # One retry so a silenced device trips offline fast (initial send + 1 retry, each 100ms).
+    max_cmd_retries: 1
+
+modbus_server:
+  - address: 1
+    modbus_id: virtual_modbus_server
+    id: modbus_server_1
+    registers:
+      # Each read returns the next counter value, so every poll publishes a distinct state the test can
+      # count (proving the read actually ran, not just that the state changed once).
+      - address: 0x01
+        value_type: U_WORD
+        read_lambda: |-
+          static uint16_t counter = 0;
+          return counter++;
+
+sensor:
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "continuous_reg"
+    address: 0x01
+    register_type: holding
+    value_type: U_WORD
+
+button:
+  - platform: template
+    name: "Start Scenario"
+    id: start_scenario_btn
+    # Trigger the first poll deterministically. PollingComponent's first update() would otherwise land
+    # somewhere in the 30s update_interval; once this one read completes, continuous re-queuing takes over.
+    on_press:
+      - lambda: "id(modbus_controller_1)->update();"
+
+switch:
+  # Toggles whether the mock server forwards its replies. On = silence (controller sees timeouts);
+  # off = answer again. The recovery test uses it to drive a live continuous poll offline and back.
+  - platform: template
+    name: "Silence Server"
+    id: silence_server_switch
+    optimistic: true
+    turn_on_action:
+      - lambda: "id(silence_server) = true;"
+    turn_off_action:
+      - lambda: "id(silence_server) = false;"

tests/integration/test_host_preferences_suspend_resume.py

@@ -0,0 +1,137 @@
+"""Test that suspending/resuming the preferences IntervalSyncer actually stops/starts flash writes."""
+
+from __future__ import annotations
+
+import asyncio
+from collections.abc import Awaitable
+from pathlib import Path
+import re
+from typing import Any
+
+from aioesphomeapi import ButtonInfo, EntityInfo
+import pytest
+
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+DEVICE_NAME = "test_suspend_resume_device"
+
+
+def find_entity_by_name(
+    entities: list[EntityInfo], entity_type: type, name: str
+) -> Any:
+    """Helper to find an entity by type and name."""
+    return next(
+        (e for e in entities if isinstance(e, entity_type) and e.name == name), None
+    )
+
+
+async def _wait_for(
+    awaitable: Awaitable[Any], message: str, timeout: float = 5.0
+) -> None:
+    """Await a future or coroutine, failing the test with a clear message on timeout."""
+    try:
+        await asyncio.wait_for(awaitable, timeout=timeout)
+    except TimeoutError:
+        pytest.fail(message)
+
+
+async def _poll_until_exists(path: Path) -> None:
+    """Poll for a file to appear, rather than guessing a sleep duration."""
+    while not path.exists():
+        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,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+    isolated_preferences: Path,
+) -> None:
+    """Test that a running syncer flushes, a suspended one doesn't, and resume restores flushing."""
+    pref_file = isolated_preferences
+
+    loop = asyncio.get_running_loop()
+    saved_in_memory = loop.create_future()
+    syncer_suspended = loop.create_future()
+    syncer_resumed = loop.create_future()
+
+    save_pattern = re.compile(r"Preference saved in memory")
+    suspend_pattern = re.compile(r"Syncer suspended")
+    resume_pattern = re.compile(r"Syncer resumed")
+
+    def check_output(line: str) -> None:
+        if save_pattern.search(line) and not saved_in_memory.done():
+            saved_in_memory.set_result(True)
+        if suspend_pattern.search(line) and not syncer_suspended.done():
+            syncer_suspended.set_result(True)
+        if resume_pattern.search(line) and not syncer_resumed.done():
+            syncer_resumed.set_result(True)
+
+    async with (
+        run_compiled(yaml_config, line_callback=check_output),
+        api_client_connected() as client,
+    ):
+        entities, _ = await client.list_entities_services()
+
+        save_button = find_entity_by_name(entities, ButtonInfo, "Save Preference")
+        suspend_button = find_entity_by_name(entities, ButtonInfo, "Suspend Syncer")
+        resume_button = find_entity_by_name(entities, ButtonInfo, "Resume Syncer")
+        assert save_button is not None, "Save Preference button not found"
+        assert suspend_button is not None, "Suspend Syncer button not found"
+        assert resume_button is not None, "Resume Syncer button not found"
+
+        # --- Positive control: a running syncer flushes to disk. Without this,
+        # the suspend assertion below could pass for the wrong reason (e.g. wrong prefs path). ---
+        client.button_command(save_button.key)
+        await _wait_for(
+            saved_in_memory, "Preference was not saved to memory within timeout"
+        )
+        await _wait_for(
+            _poll_until_exists(pref_file),
+            "Running syncer never flushed to disk; positive control failed",
+            timeout=10.0,
+        )
+        saved_in_memory = loop.create_future()
+
+        # --- Suspend: a suspended syncer must not flush. ---
+        client.button_command(suspend_button.key)
+        await _wait_for(
+            syncer_suspended, "Syncer suspend command was not processed within timeout"
+        )
+        # Delete only after suspend is confirmed: the poller is now stopped, so
+        # nothing can recreate the file before the negative assertion below.
+        pref_file.unlink()
+
+        client.button_command(save_button.key)
+        await _wait_for(
+            saved_in_memory, "Preference was not saved to memory within timeout"
+        )
+
+        # Wait well past flash_write_interval (1s): a running syncer would
+        # have flushed to disk by now, a suspended one must not have. This is a
+        # negative assertion (proving absence), so a fixed sleep is unavoidable here.
+        await asyncio.sleep(1.5)
+        assert not pref_file.exists(), (
+            "Suspended syncer flushed to disk; component.suspend did not stop the poller"
+        )
+
+        # --- Resume: flushing must restart. ---
+        client.button_command(resume_button.key)
+        await _wait_for(
+            syncer_resumed, "Syncer resume command was not processed within timeout"
+        )
+        await _wait_for(
+            _poll_until_exists(pref_file),
+            "Resumed syncer never flushed to disk; component.resume did not restart the poller",
+            timeout=10.0,
+        )

tests/integration/test_uart_mock_modbus.py

@@ -736,6 +736,68 @@ async def test_uart_mock_modbus_custom_pdu(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.asyncio
+async def test_uart_mock_modbus_continuous(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test that `continuous: true` polls faster than the update_interval.
+
+    The controller's update_interval is 30s, so without continuous polling only the boot poll would
+    run during the short test window. With continuous the read is re-queued after each success, filling
+    idle bus time, so many reads arrive. The server returns an incrementing counter, so every read is a
+    distinct published state the tracker can count. (Bus warnings are not asserted here: continuous
+    polling deliberately saturates the bus, so the occasional timing hiccup is expected and off-topic;
+    the other tests cover clean operation at normal poll rates.)
+    """
+
+    tracker = SensorTracker(["continuous_reg"])
+
+    async with (
+        run_compiled(yaml_config),
+        api_client_connected() as client,
+    ):
+        # setup_and_start_scenario presses the Start Scenario button, whose on_press triggers the
+        # controller's first update(). With continuous that one read re-queues and streams; without it
+        # the next poll would not run until the 30s update_interval elapses.
+        entities = await tracker.setup_and_start_scenario(client)
+        # Count reads over a window far shorter than the update_interval. Absent continuous polling we
+        # would see ~1 (the triggered poll); continuous re-queues, so the bus fills with reads.
+        await asyncio.sleep(3.0)
+        reads = len(tracker.sensor_states["continuous_reg"])
+        assert reads >= 5, (
+            "expected many continuous reads within the window (update_interval is 30s, so absent "
+            f"continuous polling we would see ~1), got {reads}"
+        )
+
+        # Recovery path: a live continuous poll that starts failing goes offline, and the next update()
+        # re-arms it once the device answers again. Silence the server so the poll's reads time out; with
+        # max_cmd_retries=1 and send_wait_time=100ms the device trips offline quickly and streaming stops.
+        silence = find_entity(entities, "silence_server", SwitchInfo)
+        assert silence is not None, "Silence Server switch not found"
+        start = find_entity(entities, "start_scenario", ButtonInfo)
+        assert start is not None, "Start Scenario button not found"
+
+        client.switch_command(silence.key, True)
+        await asyncio.sleep(1.0)  # let the poll fail and the device trip offline
+        plateau = len(tracker.sensor_states["continuous_reg"])
+        await asyncio.sleep(1.0)  # offline: no polls should land
+        assert len(tracker.sensor_states["continuous_reg"]) == plateau, (
+            "reads kept arriving after the server was silenced - the failed continuous poll did not stop"
+        )
+
+        # Answer again and trigger update(): the offline probe recovers the device and the continuous
+        # poll re-arms, so streaming resumes.
+        client.switch_command(silence.key, False)
+        client.button_command(start.key)
+        await asyncio.sleep(3.0)
+        resumed = len(tracker.sensor_states["continuous_reg"]) - plateau
+        assert resumed >= 5, (
+            f"continuous polling did not resume after the device recovered (got {resumed} new reads)"
+        )
+
+
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_offline(
     yaml_config: str,

tests/script/test_determine_jobs.py

@@ -1214,6 +1214,56 @@ def test_count_changed_cpp_files_with_branch() -> None:
         mock_changed.assert_called_once_with("release")
 
 
+@pytest.mark.parametrize(
+    ("changed_files", "expected"),
+    [
+        # Core C++ change runs everything
+        (["esphome/core/helpers.cpp"], (True, [])),
+        # Core Python change runs everything too
+        (["esphome/core/config.py"], (True, [])),
+        # Component C++ change: component plus dependents with C++ tests
+        (["esphome/components/time/posix_tz.cpp"], (False, ["sntp", "time"])),
+        # Component Python change shapes the host build (defines, source
+        # filters), so it must trigger the same tests as a C++ change
+        (["esphome/components/time/__init__.py"], (False, ["sntp", "time"])),
+        # Nothing to build when no selected component has C++ tests
+        (["esphome/components/homeassistant/__init__.py"], (False, [])),
+        # Test manifest override changes only that component
+        (["tests/components/time/__init__.py"], (False, ["time"])),
+        # Test source change only that component
+        (["tests/components/time/posix_tz.cpp"], (False, ["time"])),
+        # pytest files and YAML build tests do not affect the test binary
+        (["tests/components/socket/conftest.py"], (False, [])),
+        (["tests/components/time/test.esp32-idf.yaml"], (False, [])),
+        (["README.md", "script/helpers.py"], (False, [])),
+        ([], (False, [])),
+    ],
+)
+def test_determine_cpp_unit_tests(
+    changed_files: list[str],
+    expected: tuple[bool, list[str]],
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """Test which C++ unit tests a set of changed files selects."""
+    tests_dir = tmp_path / "tests" / "components"
+    for component in ("time", "sntp"):
+        (tests_dir / component).mkdir(parents=True)
+        (tests_dir / component / f"{component}.cpp").write_text("")
+    (tests_dir / "homeassistant").mkdir()
+    (tests_dir / "socket").mkdir()
+    monkeypatch.setattr(helpers, "root_path", str(tmp_path))
+    with (
+        patch.object(determine_jobs, "changed_files", return_value=changed_files),
+        patch.object(
+            helpers,
+            "create_components_graph",
+            return_value={"time": ["homeassistant", "sntp"]},
+        ),
+    ):
+        assert determine_jobs.determine_cpp_unit_tests() == expected
+
+
 def test_main_filters_components_without_tests(
     mock_determine_integration_tests: Mock,
     mock_should_run_clang_tidy: Mock,

tests/script/test_helpers.py

@@ -2031,3 +2031,92 @@ def test_get_changed_files_from_command_gh_failure_keeps_stderr() -> None:
         pytest.raises(Exception, match="maximum number of changed files"),
     ):
         _get_changed_files_from_command(["gh", "pr", "diff", "123", "--name-only"])
+
+
+@pytest.mark.parametrize(
+    ("file_path", "expected"),
+    [
+        ("esphome/components/time/posix_tz.cpp", True),
+        ("esphome/components/time/posix_tz.h", True),
+        ("esphome/components/time/__init__.py", True),
+        ("esphome/components/sntp/time.py", True),
+        ("tests/components/time/posix_tz.cpp", True),
+        ("tests/components/time/__init__.py", True),
+        # Platform override: tests/components/<component>/<domain>/__init__.py
+        ("tests/components/template/sensor/__init__.py", True),
+        # pytest-only files do not shape the C++ test binary
+        ("tests/components/socket/conftest.py", False),
+        ("tests/components/socket/test_socket.py", False),
+        ("tests/components/time/test.esp32-idf.yaml", False),
+        ("esphome/core/time.cpp", False),
+        ("esphome/config.py", False),
+        ("script/helpers.py", False),
+        ("README.md", False),
+    ],
+)
+def test_filter_cpp_unit_test_files(file_path: str, expected: bool) -> None:
+    """Test which changed files can affect a component's C++ unit test build."""
+    assert helpers.filter_cpp_unit_test_files(file_path) is expected
+
+
+@pytest.fixture
+def cpp_unit_test_tree(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> Path:
+    """Fake repo root where time, sntp and api have C++ unit tests.
+
+    homeassistant depends on time but has no C++ tests, so it must be
+    dropped from the selection; socket has only pytest files.
+    """
+    tests_dir = tmp_path / "tests" / "components"
+    for component in ("time", "sntp", "api"):
+        (tests_dir / component).mkdir(parents=True)
+        (tests_dir / component / f"{component}.cpp").write_text("")
+    (tests_dir / "homeassistant").mkdir()
+    (tests_dir / "homeassistant" / "__init__.py").write_text("")
+    (tests_dir / "socket").mkdir()
+    (tests_dir / "socket" / "conftest.py").write_text("")
+    monkeypatch.setattr(helpers, "root_path", str(tmp_path))
+    monkeypatch.setattr(
+        helpers,
+        "create_components_graph",
+        lambda: {"time": ["homeassistant", "sntp"]},
+    )
+    return tmp_path
+
+
+@pytest.mark.parametrize(
+    ("files", "expected"),
+    [
+        # Component changes expand to dependents with C++ tests
+        (["esphome/components/time/posix_tz.cpp"], ["sntp", "time"]),
+        (["esphome/components/time/__init__.py"], ["sntp", "time"]),
+        # Dependent without C++ tests is dropped
+        (["esphome/components/homeassistant/__init__.py"], []),
+        # Test changes select only that component
+        (["tests/components/time/posix_tz.cpp"], ["time"]),
+        (["tests/components/time/__init__.py"], ["time"]),
+        (["tests/components/homeassistant/__init__.py"], []),
+        (["tests/components/socket/conftest.py"], []),
+        (["tests/components/time/test.esp32-idf.yaml"], []),
+        (
+            ["esphome/components/time/__init__.py", "tests/components/api/api.cpp"],
+            ["api", "sntp", "time"],
+        ),
+        ([], []),
+    ],
+)
+@pytest.mark.usefixtures("cpp_unit_test_tree")
+def test_get_cpp_changed_components(files: list[str], expected: list[str]) -> None:
+    """Test that C++ and Python component changes select the right unit tests."""
+    assert helpers.get_cpp_changed_components(files) == expected
+
+
+def test_get_cpp_changed_components_independent_of_cwd(
+    cpp_unit_test_tree: Path,
+    tmp_path_factory: pytest.TempPathFactory,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """Test directories resolve against root_path, not the current directory."""
+    monkeypatch.chdir(tmp_path_factory.mktemp("elsewhere"))
+    assert helpers.get_cpp_changed_components(
+        ["tests/components/time/__init__.py"]
+    ) == ["time"]