[external_components] Log when a source overrides built-in components (#18805)

esphome/components/external_components/__init__.py

@@ -71,6 +71,33 @@ def _process_git_config(config: dict[str, Any], refresh: TimePeriodSeconds) -> P
     return components_dir
 
 
+def _log_overridden_components(
+    conf: dict[str, Any], component_names: list[str]
+) -> None:
+    overridden = [
+        name
+        for name in component_names
+        if (loader.CORE_COMPONENTS_PATH / name / "__init__.py").is_file()
+    ]
+    if not overridden:
+        return
+    if conf[CONF_TYPE] == TYPE_GIT:
+        source = conf[CONF_URL]
+        if ref := conf.get(CONF_REF):
+            source = f"{source}@{ref}"
+        if path := conf.get(CONF_PATH):
+            source = f"{source} ({path})"
+    else:
+        source = conf[CONF_PATH]
+    _LOGGER.info(
+        "External components are overriding built-in components:\n"
+        "  source: %s\n"
+        "  components: %s",
+        source,
+        ", ".join(sorted(overridden)),
+    )
+
+
 def _process_single_config(config: dict[str, Any]) -> None:
     conf = config[CONF_SOURCE]
     if conf[CONF_TYPE] == TYPE_GIT:
@@ -84,8 +111,8 @@ def _process_single_config(config: dict[str, Any]) -> None:
         raise NotImplementedError
 
     if config[CONF_COMPONENTS] == "all":
-        num_components = len(list(components_dir.glob("*/__init__.py")))
-        if num_components > 100:
+        component_names = [p.parent.name for p in components_dir.glob("*/__init__.py")]
+        if len(component_names) > 100:
             # Prevent accidentally including all components from an esphome fork/branch
             # In this case force the user to manually specify which components they want to include
             raise cv.Invalid(
@@ -102,6 +129,9 @@ def _process_single_config(config: dict[str, Any]) -> None:
                     [CONF_COMPONENTS, i],
                 )
         allowed_components = config[CONF_COMPONENTS]
+        component_names = allowed_components
+
+    _log_overridden_components(conf, component_names)
 
     loader.install_meta_finder(components_dir, allowed_components=allowed_components)
 

tests/component_tests/external_components/test_init.py

@@ -1,16 +1,21 @@
-"""Tests for the external_components skip-update behavior driven by CORE.skip_external_update."""
+"""Tests for the external_components config pass."""
 
+import logging
 from pathlib import Path
 from typing import Any
 from unittest.mock import MagicMock
 
+import pytest
+
 from esphome.components.external_components import do_external_components_pass
 from esphome.const import (
     CONF_EXTERNAL_COMPONENTS,
+    CONF_PATH,
     CONF_REFRESH,
     CONF_SOURCE,
     CONF_URL,
     TYPE_GIT,
+    TYPE_LOCAL,
 )
 from esphome.core import CORE, TimePeriodSeconds
 
@@ -69,3 +74,112 @@ def test_external_components_normal_refresh(
     mock_clone_or_update.assert_called_once()
     call_args = mock_clone_or_update.call_args
     assert call_args.kwargs["refresh"] == TimePeriodSeconds(days=1)
+
+
+def test_external_components_logs_built_in_override(
+    tmp_path: Path,
+    mock_clone_or_update: MagicMock,
+    mock_install_meta_finder: MagicMock,
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """A source that provides a component with the same name as a built-in one logs an info message."""
+    mock_clone_or_update.return_value = (tmp_path, None)
+    config = _make_config(tmp_path)
+
+    for name in ("gpio", "some_custom_component"):
+        component_dir = tmp_path / "components" / name
+        component_dir.mkdir()
+        (component_dir / "__init__.py").write_text("# Test component")
+
+    with caplog.at_level(logging.INFO):
+        do_external_components_pass(config)
+
+    assert (
+        "External components are overriding built-in components:\n"
+        "  source: https://github.com/test/components\n"
+        "  components: gpio" in caplog.text
+    )
+    assert "some_custom_component" not in caplog.text
+
+
+def test_external_components_override_log_includes_ref(
+    tmp_path: Path,
+    mock_clone_or_update: MagicMock,
+    mock_install_meta_finder: MagicMock,
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """A git source with a ref logs the ref appended to the url."""
+    mock_clone_or_update.return_value = (tmp_path, None)
+    config = _make_config(tmp_path)
+    config[CONF_EXTERNAL_COMPONENTS][0][CONF_SOURCE] = "github://test/components@main"
+
+    component_dir = tmp_path / "components" / "gpio"
+    component_dir.mkdir()
+    (component_dir / "__init__.py").write_text("# Test component")
+
+    with caplog.at_level(logging.INFO):
+        do_external_components_pass(config)
+
+    assert "  source: https://github.com/test/components.git@main\n" in caplog.text
+
+
+def test_external_components_override_log_includes_git_path(
+    tmp_path: Path,
+    mock_clone_or_update: MagicMock,
+    mock_install_meta_finder: MagicMock,
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """A git source with a subdirectory path logs the path after the url."""
+    mock_clone_or_update.return_value = (tmp_path, None)
+    config = _make_config(tmp_path)
+    config[CONF_EXTERNAL_COMPONENTS][0][CONF_SOURCE][CONF_PATH] = "components"
+
+    component_dir = tmp_path / "components" / "gpio"
+    component_dir.mkdir()
+    (component_dir / "__init__.py").write_text("# Test component")
+
+    with caplog.at_level(logging.INFO):
+        do_external_components_pass(config)
+
+    assert "  source: https://github.com/test/components (components)\n" in caplog.text
+
+
+def test_external_components_override_log_local_source(
+    tmp_path: Path,
+    mock_install_meta_finder: MagicMock,
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """A local source logs its resolved path."""
+    components_dir = tmp_path / "my_components"
+    gpio_dir = components_dir / "gpio"
+    gpio_dir.mkdir(parents=True)
+    (gpio_dir / "__init__.py").write_text("# Test component")
+
+    CORE.config_path = tmp_path / "dummy.yaml"
+    config = {
+        CONF_EXTERNAL_COMPONENTS: [
+            {CONF_SOURCE: {"type": TYPE_LOCAL, CONF_PATH: "my_components"}}
+        ]
+    }
+
+    with caplog.at_level(logging.INFO):
+        do_external_components_pass(config)
+
+    assert f"  source: {components_dir}\n" in caplog.text
+    assert "  components: gpio" in caplog.text
+
+
+def test_external_components_no_override_no_log(
+    tmp_path: Path,
+    mock_clone_or_update: MagicMock,
+    mock_install_meta_finder: MagicMock,
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """A source that only provides components not shipped with ESPHome logs nothing."""
+    mock_clone_or_update.return_value = (tmp_path, None)
+    config = _make_config(tmp_path)
+
+    with caplog.at_level(logging.INFO):
+        do_external_components_pass(config)
+
+    assert "are overriding built-in components" not in caplog.text