Point analyze-memory at the platformio escape hatch, test the backend-table invariant instead of asserting at import, fail blank component lists under the flag, clean the arduino idedata cache

esphome/__main__.py

@@ -48,7 +48,6 @@ from esphome.const import (
     ENV_NOGITIGNORE,
     KEY_ESP32,
     KEY_VARIANT,
-    NATIVE_TOOLCHAINS,
     SECRETS_FILES,
     Toolchain,
 )
@@ -1932,8 +1931,6 @@ _NATIVE_TOOLCHAIN_MODULES = {
     ("esp32", Toolchain.ESP_IDF): "esphome.espidf.toolchain",
     ("esp8266", Toolchain.ARDUINO): "esphome.arduino8266.toolchain",
 }
-# Structure over prose: a native toolchain the table does not serve is a bug
-assert {tc for _, tc in _NATIVE_TOOLCHAIN_MODULES} == set(NATIVE_TOOLCHAINS)
 
 
 def _native_toolchain_module():
@@ -2002,7 +1999,7 @@ def command_analyze_memory(args: ArgsProtocol, config: ConfigType) -> int:
     if native_toolchain is None and not CORE.using_toolchain_platformio:
         _LOGGER.error(
             "analyze-memory is not supported with the '%s' toolchain on %s; "
-            "it requires a PlatformIO, ESP-IDF, or native Arduino build",
+            "re-run with --toolchain platformio",
             CORE.toolchain.value if CORE.toolchain else "unresolved",
             CORE.target_platform,
         )

esphome/writer.py

@@ -610,12 +610,14 @@ def clean_build(clear_pio_cache: bool = True, *, full: bool = False):
                 _LOGGER.info("Deleting %s", idf_path)
                 rmtree(idf_path)
 
-    # The idedata cache is derived from the build but lives under the data dir,
-    # not the build path, so it must be removed separately in both modes.
-    idedata_cache = CORE.relative_internal_path("idedata", f"{CORE.name}.json")
-    if idedata_cache.is_file():
-        _LOGGER.info("Deleting %s", idedata_cache)
-        idedata_cache.unlink()
+    # The idedata caches are derived from the build but live under the data
+    # dir, not the build path, so they must be removed separately in both
+    # modes (the .arduino.json variant is the native esp8266 toolchain's).
+    for cache_name in (f"{CORE.name}.json", f"{CORE.name}.arduino.json"):
+        idedata_cache = CORE.relative_internal_path("idedata", cache_name)
+        if idedata_cache.is_file():
+            _LOGGER.info("Deleting %s", idedata_cache)
+            idedata_cache.unlink()
 
     if not clear_pio_cache:
         return

script/test_build_components.py

@@ -1074,6 +1074,13 @@ def test_components(
             )
         )
 
+    # The flag's contract is "no test matched fails": a fully blank pattern
+    # list would otherwise slide into the reference-baseline fallback and
+    # exit green while building nothing a caller asked for
+    if fail_on_no_tests and not any(component_patterns):
+        print("No components requested (blank component list)")
+        return 1
+
     # Renamed or removed fixtures must shrink coverage loudly, and the
     # reference-baseline fallback below must not mask an empty match. The
     # check is per platform: a component whose fixture exists only for other

tests/script/test_test_build_components.py

@@ -273,6 +273,18 @@ def test_components_component_with_no_base_file_fails_with_flag(
     )
 
 
+def test_components_blank_list_fails_with_flag(
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    """A fully blank component list must not slide into the baseline
+    fallback and exit green under the flag."""
+    rc = tbc.test_components(
+        [""], "esp8266-ard", "compile", False, fail_on_no_tests=True
+    )
+    assert rc == 1
+    assert "blank component list" in capsys.readouterr().out
+
+
 def test_components_empty_match_tolerated_without_flag() -> None:
     """The esp32-ard smoke leg deliberately builds only the subset with a
     matching fixture; without the flag an empty match stays green."""

tests/unit_tests/test_main.py

@@ -7390,6 +7390,15 @@ def test_compile_program_espidf_idedata_none_warns(
     assert "No idedata was generated" in caplog.text
 
 
+def test_native_toolchain_table_serves_every_native_toolchain() -> None:
+    """Every member of NATIVE_TOOLCHAINS has a backend entry; a gap would
+    surface as a targeted EsphomeError on the one affected config, and this
+    pin keeps the table from drifting when a toolchain is added."""
+    from esphome.const import NATIVE_TOOLCHAINS
+
+    assert {tc for _, tc in main._NATIVE_TOOLCHAIN_MODULES} == set(NATIVE_TOOLCHAINS)
+
+
 def test_native_toolchain_module_missing_backend_raises(tmp_path: Path) -> None:
     """A native toolchain missing from the backend table is a bug and must
     fail, not silently degrade to the PlatformIO path."""

tests/unit_tests/test_writer.py

@@ -517,10 +517,13 @@ def test_clean_build(
     dependencies_lock = tmp_path / "dependencies.lock"
     dependencies_lock.write_text("lock file")
 
-    # idedata cache lives under the data dir, not the build path.
+    # idedata caches live under the data dir, not the build path; the
+    # .arduino.json variant is the native esp8266 toolchain's.
     idedata_cache = tmp_path / "idedata" / "test.json"
     idedata_cache.parent.mkdir()
     idedata_cache.write_text("{}")
+    arduino_idedata_cache = tmp_path / "idedata" / "test.arduino.json"
+    arduino_idedata_cache.write_text("{}")
 
     # Native ESP-IDF toolchain artifacts.
     idf_build_dir = tmp_path / "build"
@@ -581,6 +584,7 @@ def test_clean_build(
     assert not piolibdeps_dir.exists()
     assert not dependencies_lock.exists()
     assert not idedata_cache.exists()
+    assert not arduino_idedata_cache.exists()
     assert not idf_build_dir.exists()
     assert not managed_components_dir.exists()
     assert not pio_components_dir.exists()