Dispatch esptool flashing via the backend hook, share the native trigger files, gate the probe, cache the closure

esphome/__main__.py

@@ -978,20 +978,15 @@ def upload_using_esptool(
 
     if file is not None:
         flash_images = [FlashImage(path=file, offset="0x0")]
-    elif CORE.using_toolchain_esp_idf:
-        from esphome.espidf import toolchain
-
-        flash_images = [
-            FlashImage(path=toolchain.get_factory_firmware_path(), offset="0x0")
-        ]
-    elif CORE.using_native_toolchain:
-        # The native backend writes PlatformIO-compatible output paths, so the
-        # shared property already points at the right file.
-        if not CORE.firmware_bin.is_file():
+    elif (native := _native_toolchain_module()) is not None:
+        # Every native backend supplies its own 0x0 flash image (bootloader
+        # and partitions included where the target needs them)
+        image = native.get_factory_firmware_path()
+        if not image.is_file():
             raise EsphomeError(
-                f"{CORE.firmware_bin} does not exist; compile the configuration first"
+                f"{image} does not exist; compile the configuration first"
             )
-        flash_images = [FlashImage(path=CORE.firmware_bin, offset="0x0")]
+        flash_images = [FlashImage(path=image, offset="0x0")]
     else:
         from esphome.platformio import toolchain
 

esphome/arduino8266/toolchain.py

@@ -61,6 +61,12 @@ def _toolchain_tool(name: str) -> Path:
     return framework.toolchain_tool(framework.get_toolchain_path(), name)
 
 
+def get_factory_firmware_path() -> Path:
+    """The image to serial-flash at 0x0 (same bytes as firmware.bin: the
+    8266 factory copy exists for artifact-contract parity, not content)."""
+    return get_build_dir() / "firmware.factory.bin"
+
+
 def get_addr2line_path() -> Path:
     return _toolchain_tool("addr2line")
 
@@ -98,22 +104,27 @@ def run_compile(config: ConfigType, verbose: bool) -> int:
         cmd += ["-j", str(jobs)]
 
     # A dry-run probe keeps a no-op rebuild quiet: ninja would only print
-    # "no work to do". cwd instead of -C also drops the "Entering
-    # directory" banner on real builds.
-    probe = subprocess.run(
-        [str(paths.ninja), "-n"],
-        cwd=build_dir,
-        env=env,
-        capture_output=True,
-        text=True,
-        check=False,
-        close_fds=False,
-    )
-    if probe.stderr.strip():
-        # A load-time diagnostic (e.g. "multiple rules generate X") flags a
-        # generator bug; the skip branch would otherwise swallow it forever
-        _LOGGER.warning("ninja: %s", probe.stderr.strip())
-    if probe.returncode == 0 and "no work to do" in probe.stdout:
+    # "no work to do". A freshly rewritten manifest all but guarantees work,
+    # so skip the probe (and its full stat pass) on that path. cwd instead
+    # of -C also drops the "Entering directory" banner on real builds.
+    skip_build = False
+    if not ninja_changed:
+        probe = subprocess.run(
+            [str(paths.ninja), "-n"],
+            cwd=build_dir,
+            env=env,
+            capture_output=True,
+            text=True,
+            check=False,
+            close_fds=False,
+        )
+        if probe.stderr.strip():
+            # A load-time diagnostic (e.g. "multiple rules generate X")
+            # flags a generator bug; the skip branch would otherwise
+            # swallow it forever
+            _LOGGER.warning("ninja: %s", probe.stderr.strip())
+        skip_build = probe.returncode == 0 and "no work to do" in probe.stdout
+    if skip_build:
         _LOGGER.debug("ninja: nothing to rebuild")
     else:
         _LOGGER.debug("Running: %s", " ".join(cmd))

script/determine-jobs.py

@@ -52,6 +52,7 @@ import argparse
 from collections import Counter
 from collections.abc import Callable
 from enum import StrEnum
+import functools
 from functools import cache
 import json
 import os
@@ -525,6 +526,13 @@ def _path_or_file_trigger(
     )
 
 
+@functools.lru_cache
+def _cached_components_closure(files: tuple[str, ...]) -> frozenset[str]:
+    """The dependency closure walk is expensive; every toolchain smoke-test
+    job asks for the same file list, so compute it once per run."""
+    return frozenset(_changed_components_closure(list(files)))
+
+
 def _changed_components_closure(files: list[str]) -> set[str]:
     """Dependency closure of the changed components, from the changed files."""
     component_files = [f for f in files if filter_component_and_test_files(f)]
@@ -545,14 +553,19 @@ def _esp32_platformio_path_or_file_trigger(files: list[str]) -> bool:
 # compile. When they change we fold the `esp32` component into the matrix so
 # the default native-IDF build path is still compiled on an infra-only PR.
 ESP_IDF_INFRA_TRIGGER_PATH_PREFIXES = ("esphome/espidf/", "esphome/build_helpers/")
-ESP_IDF_INFRA_TRIGGER_FILES = frozenset(
+# Shared library-conversion modules every native build imports; a new shared
+# module added to one native trigger set must not silently skip the other's
+# smoke test, so both sets union this one.
+_NATIVE_SHARED_TRIGGER_FILES = frozenset(
     {
-        "esphome/build_gen/espidf.py",
         "esphome/framework_helpers.py",
         "esphome/platformio/library.py",
         "esphome/platformio/extra_script.py",
     }
 )
+ESP_IDF_INFRA_TRIGGER_FILES = _NATIVE_SHARED_TRIGGER_FILES | {
+    "esphome/build_gen/espidf.py",
+}
 
 
 def _esp_idf_infra_changed(files: list[str]) -> bool:
@@ -613,7 +626,7 @@ def _toolchain_components_to_test(
     if core_changed(files) or infra_trigger(files):
         return sorted(test_set)
 
-    return sorted(test_set & _changed_components_closure(files))
+    return sorted(test_set & _cached_components_closure(tuple(files)))
 
 
 def should_run_esp32_platformio(branch: str | None = None) -> bool:
@@ -658,21 +671,18 @@ ESP8266_NATIVE_TRIGGER_PATH_PREFIXES = (
     "esphome/arduino/",
     "esphome/build_helpers/",
 )
-ESP8266_NATIVE_TRIGGER_FILES = frozenset(
-    {
-        "esphome/build_gen/arduino8266.py",
-        "esphome/build_gen/build_tool.py",
-        "esphome/platformio/extra_script.py",
-        "esphome/components/esp8266/build_surgery.py",
-        "esphome/components/esp8266/boards.py",
-        "esphome/platformio/library.py",
-        "esphome/platformio/registry.py",
-        "esphome/platformio/toolchain.py",
-        "script/test_build_components.py",
-        ".github/workflows/ci.yml",
-        ".github/actions/cache-arduino8266/action.yml",
-    }
-)
+ESP8266_NATIVE_TRIGGER_FILES = _NATIVE_SHARED_TRIGGER_FILES | {
+    "esphome/build_gen/arduino8266.py",
+    "esphome/build_gen/build_tool.py",
+    "esphome/components/esp8266/build_surgery.py",
+    "esphome/components/esp8266/boards.py",
+    "esphome/platformio/registry.py",
+    # esp8266/__init__.py imports copy_ccache_script from it
+    "esphome/platformio/toolchain.py",
+    "script/test_build_components.py",
+    ".github/workflows/ci.yml",
+    ".github/actions/cache-arduino8266/action.yml",
+}
 
 
 def _esp8266_native_path_or_file_trigger(files: list[str]) -> bool:

tests/unit_tests/test_arduino8266_toolchain.py

@@ -86,7 +86,8 @@ def test_run_compile_success(tmp_path: Path) -> None:
     with (
         patch.object(framework, "check_and_install", return_value=_paths(tmp_path)),
         patch.object(framework, "get_build_env", return_value={}),
-        patch("esphome.build_gen.arduino8266.write_project"),
+        # An unchanged manifest is what makes the -n probe run
+        patch("esphome.build_gen.arduino8266.write_project", return_value=False),
         patch.object(
             toolchain.subprocess,
             "run",
@@ -118,7 +119,8 @@ def test_run_compile_noop_skips_the_build_spawn(tmp_path: Path) -> None:
     with (
         patch.object(framework, "check_and_install", return_value=_paths(tmp_path)),
         patch.object(framework, "get_build_env", return_value={}),
-        patch("esphome.build_gen.arduino8266.write_project"),
+        # An unchanged manifest is what makes the -n probe run
+        patch("esphome.build_gen.arduino8266.write_project", return_value=False),
         patch.object(
             toolchain.subprocess,
             "run",
@@ -145,7 +147,8 @@ def test_run_compile_surfaces_probe_diagnostics(
     with (
         patch.object(framework, "check_and_install", return_value=_paths(tmp_path)),
         patch.object(framework, "get_build_env", return_value={}),
-        patch("esphome.build_gen.arduino8266.write_project"),
+        # An unchanged manifest is what makes the -n probe run
+        patch("esphome.build_gen.arduino8266.write_project", return_value=False),
         patch.object(
             toolchain.subprocess,
             "run",

tests/unit_tests/test_main.py

@@ -7124,11 +7124,15 @@ def test_upload_using_esptool_arduino_toolchain(
     tmp_path: Path,
     mock_run_external_command_main: Mock,
 ) -> None:
-    """The native ESP8266 Arduino toolchain flashes CORE.firmware_bin at 0x0."""
+    """The native ESP8266 Arduino toolchain flashes its factory image at
+    0x0, dispatched through the platform's native_toolchain_module hook."""
     setup_core(platform=PLATFORM_ESP8266, tmp_path=tmp_path, name="test")
     CORE.toolchain = Toolchain.ARDUINO
-    CORE.firmware_bin.parent.mkdir(parents=True, exist_ok=True)
-    CORE.firmware_bin.touch()
+    from esphome.arduino8266 import toolchain as native
+
+    factory = native.get_factory_firmware_path()
+    factory.parent.mkdir(parents=True, exist_ok=True)
+    factory.touch()
 
     config = {CONF_ESPHOME: {"platformio_options": {}}}
     result = upload_using_esptool(config, "/dev/ttyUSB0", None, None)
@@ -7137,7 +7141,7 @@ def test_upload_using_esptool_arduino_toolchain(
     cmd_list = list(mock_run_external_command_main.call_args[0][1:])
     firmware_offset_idx = cmd_list.index("write-flash") + 4
     assert cmd_list[firmware_offset_idx] == "0x0"
-    assert cmd_list[firmware_offset_idx + 1] == str(CORE.firmware_bin)
+    assert cmd_list[firmware_offset_idx + 1] == str(factory)
 
 
 @pytest.mark.parametrize(