Record bootloader hooks from the configured build, make config name sets immutable, never delete an entry on a transient read error

esphome/build_gen/espidf.py

@@ -291,6 +291,13 @@ include($ENV{{IDF_PATH}}/tools/cmake/project.cmake)
 
 project({CORE.name})
 
+# Record the bootloader customization channels the cache cannot replay;
+# esphome.espidf.bootloader bypasses the cache when any is non-empty.
+idf_build_get_property(esphome_bl_dirs BOOTLOADER_EXTRA_COMPONENT_DIRS)
+idf_build_get_property(esphome_bl_args EXTRA_CMAKE_ARGS)
+file(WRITE ${{CMAKE_BINARY_DIR}}/esphome_bootloader_hooks.txt
+     "${{esphome_bl_dirs}}${{BOOTLOADER_IGNORE_EXTRA_COMPONENT}}${{esphome_bl_args}}")
+
 # Emit per-memory-type JSON size data for ESPHome to read post-build.
 # json2 stays small; raw dumps every symbol (~2s on a large map) and
 # this command runs inside the link edge, blocking everything downstream.

esphome/espidf/__init__.py

@@ -12,6 +12,10 @@ from typing import TYPE_CHECKING
 if TYPE_CHECKING:
     from pathlib import Path
 
+# Written by the generated CMakeLists after project(); holds the bootloader
+# customization channels the cache cannot replay (see espidf.bootloader).
+BOOTLOADER_HOOKS_FILE = "esphome_bootloader_hooks.txt"
+
 
 def variant_to_idf_target(variant: str) -> str:
     """Map an esp32 variant name (e.g. "ESP32S3") to its ESP-IDF target name."""

script/check_idf_py_equivalence.py

@@ -184,10 +184,10 @@ def _bootloader_parity(build_path: Path) -> list[str]:
     # pylint: disable=protected-access
     from esphome.espidf import bootloader, toolchain
 
-    bin_path = build_path / "build" / "bootloader" / "bootloader.bin"
     if not bootloader.tree_uses_cached_bootloader(build_path / "build"):
         print("note: tree not in cached mode; bootloader parity not exercised")
         return []
+    bin_path = build_path / "build" / "bootloader" / "bootloader.bin"
     cached = bin_path.read_bytes()
     bin_path.unlink()  # the rebuild must produce it, never compare to itself
     os.environ[bootloader.BOOTLOADER_CACHE_ENV] = "0"

tests/unit_tests/build_gen/test_espidf.py

@@ -175,6 +175,20 @@ def test_get_project_cmakelists_size_command_uses_json2() -> None:
     assert "--format=json2" in content
 
 
+def test_get_project_cmakelists_records_bootloader_hooks() -> None:
+    """The post-project() dump feeds espidf.bootloader's bypass check."""
+    from esphome.espidf import BOOTLOADER_HOOKS_FILE
+
+    content = _render()
+    assert f"file(WRITE ${{CMAKE_BINARY_DIR}}/{BOOTLOADER_HOOKS_FILE}" in content
+    for source in (
+        "esphome_bl_dirs BOOTLOADER_EXTRA_COMPONENT_DIRS",
+        "${BOOTLOADER_IGNORE_EXTRA_COMPONENT}",
+        "esphome_bl_args EXTRA_CMAKE_ARGS",
+    ):
+        assert source in content
+
+
 def test_get_project_cmakelists_uses_supplied_builtin_components() -> None:
     """A cached list replaces project_description.json and is still filtered
     by EXCLUDE_COMPONENTS."""