Reject unsupported CLI toolchains on every platform and complete the native CI triggers

esphome/components/esp32/__init__.py

@@ -1053,6 +1053,11 @@ def _resolve_toolchain(value: ConfigType) -> ConfigType:
     # CORE.toolchain instead of re-resolving it from the config dict.
     if CORE.toolchain is None:
         CORE.toolchain = value.get(CONF_TOOLCHAIN, Toolchain.ESP_IDF)
+    if CORE.toolchain not in (Toolchain.PLATFORMIO, Toolchain.ESP_IDF):
+        raise cv.Invalid(
+            f"Unsupported toolchain '{CORE.toolchain.value}' for ESP32. "
+            "Supported toolchains are 'platformio' and 'esp-idf'."
+        )
     return value
 
 

esphome/components/nrf52/__init__.py

@@ -128,6 +128,11 @@ def set_core_data(config: ConfigType) -> ConfigType:
 def _resolve_toolchain(config: ConfigType) -> ConfigType:
     if CORE.toolchain is None:
         CORE.toolchain = config.get(CONF_TOOLCHAIN, Toolchain.SDK_NRF)
+    if CORE.toolchain not in (Toolchain.PLATFORMIO, Toolchain.SDK_NRF):
+        raise cv.Invalid(
+            f"Unsupported toolchain '{CORE.toolchain.value}' for nRF52. "
+            "Supported toolchains are 'platformio' and 'sdk-nrf'."
+        )
     return config
 
 

script/determine-jobs.py

@@ -644,6 +644,7 @@ ESP8266_NATIVE_TRIGGER_FILES = frozenset(
         "esphome/components/esp8266/build_surgery.py",
         "esphome/components/esp8266/boards.py",
         "esphome/platformio/library.py",
+        "esphome/platformio/toolchain.py",
         "script/test_build_components.py",
         ".github/workflows/ci.yml",
     }

tests/component_tests/esp32/test_esp32.py

@@ -131,6 +131,20 @@ def test_esp32_rejects_unsupported_toolchains(
         CONFIG_SCHEMA({"variant": VARIANT_ESP32, "toolchain": config_toolchain})
 
 
+def test_esp32_rejects_unsupported_cli_toolchain(
+    set_core_config: SetCoreConfigCallable,
+) -> None:
+    """A --toolchain the platform cannot serve fails instead of silently
+    building with PlatformIO (the CLI path bypasses the YAML validator)."""
+    set_core_config(PlatformFramework.ESP32_IDF)
+
+    from esphome.components.esp32 import CONFIG_SCHEMA
+
+    CORE.toolchain = Toolchain.ARDUINO
+    with pytest.raises(cv.Invalid, match="Unsupported toolchain 'arduino'"):
+        CONFIG_SCHEMA({"variant": VARIANT_ESP32})
+
+
 @pytest.mark.parametrize(
     ("config", "error_match"),
     [

tests/script/test_determine_jobs.py

@@ -3086,6 +3086,8 @@ def test_esp8266_native_components_full_list_on_infra_change() -> None:
         # Top-level esphome/*.py modules the backend imports directly
         ["esphome/framework_helpers.py"],
         ["esphome/writer.py"],
+        # ccache_path imports from platformio/toolchain.py
+        ["esphome/platformio/toolchain.py"],
     ):
         with (
             patch.object(determine_jobs, "changed_files", return_value=changed),

tests/unit_tests/test_nrf52_framework.py

@@ -531,3 +531,14 @@ def testget_tools_path_default_is_global_cache(
         Path(platformdirs.user_cache_dir("esphome", appauthor=False)) / "sdk-nrf"
     ).resolve()
     assert get_sdk_nrf_tools_path() == expected
+
+
+def test_resolve_toolchain_rejects_unsupported() -> None:
+    """A --toolchain nRF52 cannot serve fails instead of degrading silently."""
+    from esphome.components.nrf52 import _resolve_toolchain
+    import esphome.config_validation as cv
+    from esphome.const import Toolchain
+
+    CORE.toolchain = Toolchain.ARDUINO
+    with pytest.raises(cv.Invalid, match="Unsupported toolchain 'arduino'"):
+        _resolve_toolchain({})