Fail closed in CI with ESPHOME_LDGEN_STRICT

.github/workflows/ci-docker.yml

@@ -219,5 +219,6 @@ jobs:
         run: |
           docker run --rm \
             -v "${{ github.workspace }}/docker/test_configs:/config" \
+            -e ESPHOME_LDGEN_STRICT=1 \
             "ghcr.io/esphome/esphome-amd64:${{ needs.check-docker.outputs.tag }}" \
             compile "${{ matrix.id }}.yaml"

esphome/build_gen/espidf.py

@@ -50,12 +50,15 @@ if(COMMAND __ldgen_get_lib_deps_of_target)
             list(REMOVE_ITEM ${out_list_var} idf::src __idf_src)
             list(LENGTH ${out_list_var} esphome_ldgen_after)
             if(esphome_ldgen_before EQUAL esphome_ldgen_after)
-                message(WARNING "ESPHome ldgen app archive exclusion matched "
+                message(@SEVERITY@ "ESPHome ldgen app archive exclusion matched "
                     "nothing; app edits will regenerate sections.ld.")
             endif()
         endif()
         set(${out_list_var} ${${out_list_var}} PARENT_SCOPE)
     endfunction()
+else()
+    message(@MISSING@ "ESPHome ldgen override target not found; "
+        "app edits will regenerate sections.ld.")
 endif()"""
 
 
@@ -148,8 +151,16 @@ def get_project_cmakelists(
     )
 
     # Stops the ~3s sections.ld regeneration on app-only edits; see
-    # _LDGEN_OVERRIDE. ESPHOME_LDGEN_FULL_DEPS=1 restores stock behavior.
-    ldgen_override = "" if get_bool_env("ESPHOME_LDGEN_FULL_DEPS") else _LDGEN_OVERRIDE
+    # _LDGEN_OVERRIDE. ESPHOME_LDGEN_FULL_DEPS=1 restores stock behavior;
+    # ESPHOME_LDGEN_STRICT=1 (CI) fails the configure when an IDF bump
+    # breaks the override instead of degrading to stock deps.
+    if get_bool_env("ESPHOME_LDGEN_FULL_DEPS"):
+        ldgen_override = ""
+    else:
+        strict = get_bool_env("ESPHOME_LDGEN_STRICT")
+        ldgen_override = _LDGEN_OVERRIDE.replace(
+            "@SEVERITY@", "FATAL_ERROR" if strict else "WARNING"
+        ).replace("@MISSING@", "FATAL_ERROR" if strict else "STATUS")
 
     # CMake variables registered via cg.add_cmake_arg(). Emitted before
     # include(project.cmake) so values like EXCLUDE_COMPONENTS are already

esphome/espidf/toolchain.py

@@ -497,11 +497,14 @@ def _warn_if_app_archive_mapped() -> None:
             if _APP_ARCHIVE_MAPPED_RE.search(
                 Path(fragment).read_text(encoding="utf-8")
             ):
-                _LOGGER.warning(
-                    "Linker fragment %s maps the app archive; its entries may be "
-                    "skipped. Set ESPHOME_LDGEN_FULL_DEPS=1 and rebuild.",
-                    fragment,
+                msg = (
+                    f"Linker fragment {fragment} maps the app archive; its "
+                    "entries may be skipped. Set ESPHOME_LDGEN_FULL_DEPS=1 "
+                    "and rebuild."
                 )
+                if get_bool_env("ESPHOME_LDGEN_STRICT"):
+                    raise EsphomeError(msg)
+                _LOGGER.warning("%s", msg)
                 return
     except OSError as e:
         _LOGGER.debug("Skipping ldgen fragment check: %s", e)

tests/unit_tests/build_gen/test_espidf.py

@@ -9,7 +9,6 @@ from unittest.mock import patch
 
 import pytest
 
-from esphome.build_gen import espidf as build_gen_espidf
 from esphome.components.esp32 import (
     KEY_COMPONENTS,
     KEY_ESP32,
@@ -171,13 +170,30 @@ def test_get_project_cmakelists_emits_ldgen_override(
     """Both renders override the ldgen dep walker to drop the app archive,
     after include(project.cmake) which defines the original."""
     monkeypatch.delenv("ESPHOME_LDGEN_FULL_DEPS", raising=False)
+    monkeypatch.delenv("ESPHOME_LDGEN_STRICT", raising=False)
     content = _render(minimal=minimal)
-    assert build_gen_espidf._LDGEN_OVERRIDE in content
+    assert "REMOVE_ITEM ${out_list_var} idf::src __idf_src" in content
+    assert 'message(WARNING "ESPHome ldgen app archive exclusion' in content
+    assert 'message(STATUS "ESPHome ldgen override target not found' in content
     assert content.index("tools/cmake/project.cmake") < content.index(
         "function(__ldgen_get_lib_deps_of_target"
     )
 
 
+def test_get_project_cmakelists_ldgen_strict_fails_closed(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """ESPHOME_LDGEN_STRICT turns both degradation paths into hard errors so
+    CI fails right away when an IDF bump breaks the override."""
+    monkeypatch.delenv("ESPHOME_LDGEN_FULL_DEPS", raising=False)
+    monkeypatch.setenv("ESPHOME_LDGEN_STRICT", "1")
+    content = _render()
+    assert 'message(FATAL_ERROR "ESPHome ldgen app archive exclusion' in content
+    assert 'message(FATAL_ERROR "ESPHome ldgen override target not found' in content
+    assert "@SEVERITY@" not in content
+    assert "@MISSING@" not in content
+
+
 def test_get_project_cmakelists_ldgen_full_deps_escape_hatch(
     monkeypatch: pytest.MonkeyPatch,
 ) -> None:

tests/unit_tests/test_espidf_toolchain.py

@@ -633,9 +633,13 @@ def _write_fragments_build_ninja(tmp_path: Path, fragments: list[Path]) -> None:
 
 
 def test_warn_if_app_archive_mapped_warns(
-    setup_core: Path, tmp_path: Path, caplog: pytest.LogCaptureFixture
+    setup_core: Path,
+    tmp_path: Path,
+    caplog: pytest.LogCaptureFixture,
+    monkeypatch: pytest.MonkeyPatch,
 ) -> None:
     """A fragment naming the app archive triggers the loud warning."""
+    monkeypatch.delenv("ESPHOME_LDGEN_STRICT", raising=False)
     _setup_build(setup_core)
     frag = tmp_path / "linker.lf"
     frag.write_text("[mapping:evil]\narchive: libsrc.a\nentries:\n    * (noflash)\n")
@@ -644,6 +648,19 @@ def test_warn_if_app_archive_mapped_warns(
     assert "maps the app archive" in caplog.text
 
 
+def test_warn_if_app_archive_mapped_strict_raises(
+    setup_core: Path, tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """Under ESPHOME_LDGEN_STRICT a mapped app archive fails the build."""
+    monkeypatch.setenv("ESPHOME_LDGEN_STRICT", "1")
+    _setup_build(setup_core)
+    frag = tmp_path / "linker.lf"
+    frag.write_text("[mapping:evil]\narchive: libsrc.a\n")
+    _write_fragments_build_ninja(tmp_path, [frag])
+    with pytest.raises(EsphomeError, match="maps the app archive"):
+        toolchain._warn_if_app_archive_mapped()
+
+
 def test_warn_if_app_archive_mapped_clean(
     setup_core: Path, tmp_path: Path, caplog: pytest.LogCaptureFixture
 ) -> None: