Gate the ccache sloppiness on emission for the IDF backend too

esphome/build_gen/espidf.py

@@ -8,6 +8,7 @@ from esphome.build_helpers import pch
 from esphome.build_helpers.pch import (
     PCH_DEFAULT_HEADERS,
     PCH_HEADER_NAME,
+    mark_pch_emitted,
     pch_enabled,
     pch_header_text,
 )
@@ -371,6 +372,8 @@ def write_project(
             CORE.relative_build_path("build", PCH_HEADER_NAME),
             pch_header_text(PCH_DEFAULT_HEADERS),
         )
+        # Consumers carry the -include; gate the ccache relaxation on it
+        mark_pch_emitted()
 
     # Snapshot the exclusion set so has_outdated_files() can trigger a
     # discovery reconfigure when it changes. Excluded components never

tests/unit_tests/test_espidf_framework.py

@@ -19,6 +19,7 @@ from unittest.mock import MagicMock, patch
 
 import pytest
 
+from esphome.build_helpers.pch import _PCHData
 from esphome.espidf.framework import (
     ESPHOME_STAMP_FILE,
     STAMP_SCHEMA_VERSION,
@@ -1565,10 +1566,14 @@ def _ccache_patches(tmp_path: Path, which: str | None, build_path: Path | None):
             "esphome.espidf.framework.get_idf_tools_path",
             return_value=tmp_path / "tools",
         ),
-        # ccache_defaults_env (build_helpers.ccache) reads CORE at call time
+        # ccache_defaults_env and the pch emission flag read CORE at call time
         patch(
             "esphome.core.CORE",
-            SimpleNamespace(build_path=build_path),
+            SimpleNamespace(
+                build_path=build_path,
+                # Pre-marked: these env tests model a pch-emitting build
+                data={"pch": _PCHData(emitted=True)},
+            ),
         ),
     )