Merge branch 'esp8266-native-pch' into esp32-idf-pch

esphome/build_gen/arduino8266.py

@@ -1254,7 +1254,7 @@ def write_project(paths: InstalledPaths, ccache: str | None) -> bool:
         # Relative -include (resolved from the ninja cwd, where the header
         # lives): an absolute path would put the per-device build path on
         # every compile command and defeat cross-device ccache sharing
-        cxx_parts = src_other + [f"-include {PCH_HEADER_NAME}"]
+        cxx_parts = src_other + [f"-Winvalid-pch -include {PCH_HEADER_NAME}"]
         lines.append(f"srccxxflags = {' '.join(cxx_parts)}")
         src_cxx_flags = "$srccxxflags"
         src_cxx_implicit = gch

esphome/build_helpers/ccache.py

@@ -97,4 +97,8 @@ def effective_ccache_basedir() -> str:
     wins, else the resolved build path (matching ccache_defaults_env)."""
     from esphome.core import CORE
 
-    return os.environ.get("CCACHE_BASEDIR") or str(Path(CORE.build_path).resolve())
+    raw = os.environ.get("CCACHE_BASEDIR")
+    if raw is not None:
+        # An explicitly empty value disables ccache's rewriting; mirror it
+        return raw
+    return str(Path(CORE.build_path).resolve())

esphome/build_helpers/pch.py

@@ -2,7 +2,9 @@
 
 Safe by construction when the prefix header mirrors what the TUs already
 include first (ESP8266); a backend may instead inject a curated set of
-self-contained core headers (ESP-IDF).
+self-contained core headers (ESP-IDF). User sources from ``esphome:
+includes:`` also receive the prefix, so they now see defines.h (and
+Arduino.h on Arduino platforms) even when they did not include it.
 """
 
 from __future__ import annotations

esphome/platformio/pch.py.script

@@ -50,11 +50,13 @@ def _include_closure(src_dir: Path, roots: list) -> dict:
 
 def _shell_arg(element) -> str:
     """One compiler argv from one SCons element, matching the real spawn:
-    SCons whole-quotes spaced elements, the shell unquotes the rest."""
+    SCons whole-quotes spaced elements, the shell unquotes the rest. On
+    Windows there is no POSIX shell pass and shlex would eat path
+    backslashes."""
     arg = str(element)
-    if " " in arg:
+    if " " in arg or os.name == "nt":
         return arg.replace('\\"', '"')
-    return shlex.split(arg)[0] if arg else arg
+    return shlex.split(arg)[0] if arg.strip() else arg
 
 
 def _setup_pch() -> None:
@@ -104,10 +106,13 @@ def _setup_pch() -> None:
     for package in sorted(platform.packages):
         try:
             version = platform.get_package_version(package)
-        except Exception as err:  # noqa: BLE001 -- absent optional package
-            # Folded into the digest so an unexpected lookup failure still
-            # invalidates instead of hashing like a fixed absence
-            version = f"error:{type(err).__name__}"
+        except KeyError:
+            version = None  # absent optional package
+        except Exception as err:  # noqa: BLE001
+            # Without trustworthy package identity a stale .gch could be
+            # reused across upgrades; skip the pch instead
+            print(f"ESPHome: skipping precompiled header: {err}")
+            return
         digest.update(f"{package}={version}".encode())
         digest.update(b"\0")
     closure = _include_closure(src_dir, [*include_headers, _CORE_HEADER])
@@ -133,9 +138,13 @@ def _setup_pch() -> None:
             and not inc_dir.is_relative_to(src_dir)
         ):
             continue
-        for local in sorted(inc_dir.rglob("*.h")):
+        for local in sorted(p for p in inc_dir.rglob("*") if p.is_file()):
+            try:
+                data = local.read_bytes()
+            except OSError:
+                data = b"<unreadable>"
             digest.update(str(local.relative_to(proj_dir)).encode())
-            digest.update(local.read_bytes())
+            digest.update(data)
             digest.update(b"\0")
     checksum = digest.hexdigest()
 
@@ -215,8 +224,11 @@ def _setup_pch() -> None:
 
     # Prepended so it is processed before the build_src_flags -include
     # entries: GCC only uses a .gch while no other tokens have been seen.
-    projenv.Prepend(CXXFLAGS=["-include", header.name])  # noqa: F821
+    projenv.Prepend(CXXFLAGS=["-Winvalid-pch", "-include", header.name])  # noqa: F821
     print("ESPHome: Compiling with precompiled header")
 
 
-_setup_pch()
+try:
+    _setup_pch()
+except Exception as err:  # noqa: BLE001 -- a speedup must never break the build
+    print(f"ESPHome: precompiled header setup failed; compiling without it: {err}")

esphome/writer.py

@@ -609,6 +609,17 @@ def clean_build(clear_pio_cache: bool = True, *, full: bool = False):
             if idf_path.is_dir():
                 _LOGGER.info("Deleting %s", idf_path)
                 rmtree(idf_path)
+        # The PlatformIO pch artifacts live at the project root so the
+        # relative -include resolves; a partial clean must drop them too
+        for name in (
+            "esphome_pch.h",
+            "esphome_pch.h.gch",
+            "esphome_pch.h.gch.sum",
+            "esphome_pch.h.gch.failed",
+        ):
+            pch_path = CORE.relative_build_path(name)
+            if pch_path.is_file():
+                pch_path.unlink()
 
     # The idedata caches are derived from the build but live under the data
     # dir, not the build path, so they must be removed separately in both

tests/unit_tests/build_gen/test_arduino8266.py

@@ -1766,7 +1766,7 @@ def test_write_project_pch_no_device_path_poison(tmp_path: Path) -> None:
         CORE.build_path = tmp_path / name
         _set_flags("-DPIO_FRAMEWORK_ARDUINO_LWIP2_HIGHER_BANDWIDTH_LOW_FLASH")
         content = _write_ninja(paths, ccache="/usr/bin/ccache")
-        assert "srccxxflags = -include esphome_pch.h" in content
+        assert "srccxxflags = -Winvalid-pch -include esphome_pch.h" in content
         sums.append(
             (CORE.relative_pioenvs_path(name) / "esphome_pch.h.gch.sum").read_text()
         )

tests/unit_tests/test_platformio_pch_script.py

@@ -56,7 +56,9 @@ class _FakeSConsEnv(dict):
 def _fake_cxx(tmp_path: Path, fail: bool = False) -> Path:
     """A compiler stand-in that records its argv and writes the -o target."""
     cxx = tmp_path / "fake-gxx"
-    body = 'printf -- ---call---\\\\n >> "$0.argv"; printf \'%s\\n\' "$@" >> "$0.argv"\n'
+    body = (
+        'printf -- ---call---\\\\n >> "$0.argv"; printf \'%s\\n\' "$@" >> "$0.argv"\n'
+    )
     if fail:
         body += "echo boom >&2\nexit 1\n"
     else:
@@ -95,7 +97,7 @@ def test_pch_script_builds_and_prepends_relative_include(tmp_path: Path) -> None
     assert (proj / "esphome_pch.h.gch").is_file()
     assert len((proj / "esphome_pch.h.gch.sum").read_text().strip()) == 64
     # Relative include: an absolute path would poison ccache keys
-    assert scons_env.prepended == ["-include", "esphome_pch.h"]
+    assert scons_env.prepended == ["-Winvalid-pch", "-include", "esphome_pch.h"]
     # ccache settings land on the SCons ENV only, never os.environ
     assert scons_env["ENV"]["CCACHE_SLOPPINESS"] == "pch_defines,time_macros"
     assert scons_env["ENV"]["CCACHE_PCH_EXTSUM"] == "true"