[core] Persist & restore CORE.toolchain through StorageJSON (#16531)

esphome/storage_json.py

@@ -14,6 +14,7 @@ from esphome.const import (
     KEY_CORE,
     KEY_TARGET_FRAMEWORK,
     KEY_TARGET_PLATFORM,
+    Toolchain,
 )
 from esphome.core import CORE
 from esphome.helpers import write_file_if_changed
@@ -98,6 +99,7 @@ class StorageJSON:
         no_mdns: bool,
         framework: str | None = None,
         core_platform: str | None = None,
+        toolchain: str | None = None,
     ) -> None:
         # Version of the storage JSON schema
         assert storage_version is None or isinstance(storage_version, int)
@@ -134,6 +136,8 @@ class StorageJSON:
         self.framework = framework
         # The core platform of this firmware. Like "esp32", "rp2040", "host" etc.
         self.core_platform = core_platform
+        # The toolchain used for the build ("platformio" / "esp-idf")
+        self.toolchain = toolchain
 
     def as_dict(self):
         return {
@@ -153,6 +157,7 @@ class StorageJSON:
             "no_mdns": self.no_mdns,
             "framework": self.framework,
             "core_platform": self.core_platform,
+            "toolchain": self.toolchain,
         }
 
     def to_json(self):
@@ -189,6 +194,7 @@ class StorageJSON:
             ),
             framework=esph.target_framework,
             core_platform=esph.target_platform,
+            toolchain=esph.toolchain.value if esph.toolchain is not None else None,
         )
 
     @staticmethod
@@ -236,6 +242,7 @@ class StorageJSON:
         no_mdns = storage.get("no_mdns", False)
         framework = storage.get("framework")
         core_platform = storage.get("core_platform")
+        toolchain = storage.get("toolchain")
         return StorageJSON(
             storage_version,
             name,
@@ -253,6 +260,7 @@ class StorageJSON:
             no_mdns,
             framework,
             core_platform,
+            toolchain,
         )
 
     @staticmethod
@@ -273,6 +281,18 @@ class StorageJSON:
         """
         CORE.name = self.name
         CORE.build_path = self.build_path
+        # Restore toolchain so upload/logs picks the right firmware_bin path.
+        # An unknown value (corrupt sidecar, or written by a newer ESPHome)
+        # just leaves CORE.toolchain None — the fallback then picks PlatformIO.
+        if self.toolchain and CORE.toolchain is None:
+            try:
+                CORE.toolchain = Toolchain(self.toolchain)
+            except ValueError:
+                _LOGGER.debug(
+                    "Ignoring unknown toolchain %r from %s",
+                    self.toolchain,
+                    storage_path(),
+                )
         target_platform = self.core_platform or self.target_platform.lower()
         CORE.data[KEY_CORE] = {
             KEY_TARGET_PLATFORM: target_platform,