[ci] Cache clang-tidy idedata and key ESP-IDF cache on Python version (#18868)

.github/actions/cache-clang-tidy-idedata/action.yml

@@ -0,0 +1,50 @@
+name: Cache clang-tidy idedata
+description: >
+  Cache the clang-tidy idedata and the headers it references under .temp
+  (headers only, about 30MB per env). Run after restore-python and cache-esp-idf.
+inputs:
+  environment:
+    description: 'clang-tidy environment (e.g. esp32-idf-tidy).'
+    required: true
+runs:
+  using: composite
+  steps:
+    - name: Compute cache key
+      id: key
+      shell: bash
+      run: |
+        . venv/bin/activate
+        [ -n "${{ inputs.environment }}" ] || { echo "::error::cache-clang-tidy-idedata: 'environment' input is empty"; exit 1; }
+        hash=$(python -c 'import sys; sys.path.insert(0, "script"); from clang_tidy_hash import idedata_cache_hash; print(idedata_cache_hash("${{ inputs.environment }}"))')
+        pyver=$(python -c 'import platform; print(platform.python_version())')
+        # Generating idedata is what installs ESP-IDF; never skip it over a missing
+        # install. This also skips the save, so a dev run that installs ESP-IDF
+        # warms the idedata cache on the next run.
+        if [ -d ~/.esphome-idf/frameworks ]; then
+          echo "skip=false" >> "$GITHUB_OUTPUT"
+        else
+          echo "ESP-IDF install missing, not using the clang-tidy idedata cache"
+          echo "skip=true" >> "$GITHUB_OUTPUT"
+        fi
+        echo "key=${{ runner.os }}-tidy-idedata-${{ inputs.environment }}-$hash-py$pyver" >> "$GITHUB_OUTPUT"
+        {
+          echo "path<<EOF"
+          printf '%s\n' '.temp/idedata-*.json' '.temp/idedata-*.hash'
+          printf '.temp/**/*.%s\n' h hpp hh hxx inc inl ipp tpp
+          echo "EOF"
+        } >> "$GITHUB_OUTPUT"
+    # Mirror cache-esp-idf: write on dev, restore-only on PRs. The post-step
+    # save only runs when the job succeeded, so a failed generation is never saved.
+    # Extend the extension list if a component ships extensionless headers.
+    - name: Cache clang-tidy idedata (write on dev)
+      if: (github.ref == 'refs/heads/dev' || contains(github.event.pull_request.labels.*.name, 'ci-cache-write')) && steps.key.outputs.skip != 'true'
+      uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
+      with:
+        path: ${{ steps.key.outputs.path }}
+        key: ${{ steps.key.outputs.key }}
+    - name: Cache clang-tidy idedata (restore-only off dev)
+      if: github.ref != 'refs/heads/dev' && !contains(github.event.pull_request.labels.*.name, 'ci-cache-write') && steps.key.outputs.skip != 'true'
+      uses: actions/cache/restore@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
+      with:
+        path: ${{ steps.key.outputs.path }}
+        key: ${{ steps.key.outputs.key }}

.github/actions/cache-esp-idf/action.yml

@@ -26,6 +26,9 @@ runs:
       # The native-IDF version is pinned in code, not in any file that feeds the
       # other cache keys, so resolve it explicitly. Keying on it means the cache
       # invalidates on a version bump (actions/cache never overwrites a key).
+      # Also key on the Python version: the cached IDF venv links to the
+      # runner's toolcache interpreter and is reinstalled every run after a
+      # runner image bump.
       id: version
       shell: bash
       run: |
@@ -36,19 +39,22 @@ runs:
           version=$(python -c 'from esphome.components.esp32 import ESP_IDF_FRAMEWORK_VERSION_LOOKUP as L; print(L["recommended"])')
         fi
         echo "version=$version" >> "$GITHUB_OUTPUT"
+        echo "python-version=$(python -c 'import platform; print(platform.python_version())')" >> "$GITHUB_OUTPUT"
     # Mirror the adjacent PlatformIO cache: only dev-branch runs write the
     # shared cache (so it lives in the default-branch scope readable by all
     # PRs), and PRs are restore-only -- they never push multi-GB artifacts into
-    # their own scope / the repo quota (e.g. on a version-bump PR).
+    # their own scope / the repo quota (e.g. on a version-bump PR). The
+    # ci-cache-write label lets a PR write into its own scope to test the hit path;
+    # that costs about 1GB of the repo cache quota per run, so remove it when done.
     - name: Cache ESP-IDF install (write on dev)
-      if: github.ref == 'refs/heads/dev' && inputs.restore-only != 'true'
+      if: (github.ref == 'refs/heads/dev' || contains(github.event.pull_request.labels.*.name, 'ci-cache-write')) && inputs.restore-only != 'true'
       uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
       with:
         path: ~/.esphome-idf
-        key: ${{ runner.os }}-esphome-idf-${{ steps.version.outputs.version }}
+        key: ${{ runner.os }}-esphome-idf-${{ steps.version.outputs.version }}-py${{ steps.version.outputs.python-version }}
     - name: Cache ESP-IDF install (restore-only off dev)
-      if: github.ref != 'refs/heads/dev' || inputs.restore-only == 'true'
+      if: github.ref != 'refs/heads/dev' && !contains(github.event.pull_request.labels.*.name, 'ci-cache-write') || inputs.restore-only == 'true'
       uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
       with:
         path: ~/.esphome-idf
-        key: ${{ runner.os }}-esphome-idf-${{ steps.version.outputs.version }}
+        key: ${{ runner.os }}-esphome-idf-${{ steps.version.outputs.version }}-py${{ steps.version.outputs.python-version }}

.github/workflows/ci.yml

@@ -649,6 +649,12 @@ jobs:
         with:
           framework: arduino
 
+      - name: Cache clang-tidy idedata
+        if: matrix.cache_idf
+        uses: ./.github/actions/cache-clang-tidy-idedata
+        with:
+          environment: esp32-arduino-tidy
+
       - name: Cache nRF Connect SDK install
         if: matrix.cache_sdk_nrf
         uses: ./.github/actions/cache-sdk-nrf
@@ -730,6 +736,11 @@ jobs:
       - name: Cache ESP-IDF install
         uses: ./.github/actions/cache-esp-idf
 
+      - name: Cache clang-tidy idedata
+        uses: ./.github/actions/cache-clang-tidy-idedata
+        with:
+          environment: esp32-idf-tidy
+
       - name: Register problem matchers
         run: |
           echo "::add-matcher::.github/workflows/matchers/gcc.json"
@@ -809,6 +820,11 @@ jobs:
       - name: Cache ESP-IDF install
         uses: ./.github/actions/cache-esp-idf
 
+      - name: Cache clang-tidy idedata
+        uses: ./.github/actions/cache-clang-tidy-idedata
+        with:
+          environment: esp32-idf-tidy
+
       - name: Register problem matchers
         run: |
           echo "::add-matcher::.github/workflows/matchers/gcc.json"
@@ -866,16 +882,19 @@ jobs:
             name: Run script/clang-tidy for ESP32 S3
             # yamllint disable-line rule:line-length
             options: --environment esp32s3-idf-tidy --grep SOC_TEMP_SENSOR_SUPPORTED --grep USE_ESP32_VARIANT_ESP32S3 --grep USE_LOGGER_USB_CDC
+            tidy_environment: esp32s3-idf-tidy
           - id: clang-tidy
             name: Run script/clang-tidy for ESP32 P4
             # P4 has no native Wi-Fi/BLE; those run over the hosted co-processor,
             # so their code paths differ -- lint them under the P4 build too.
             # yamllint disable-line rule:line-length
             options: --environment esp32p4-idf-tidy --grep USE_ESP32_VARIANT_ESP32P4 --grep USE_ESP32_HOSTED --grep USE_WIFI --grep USE_BLE
+            tidy_environment: esp32p4-idf-tidy
           - id: clang-tidy
             name: Run script/clang-tidy for ESP32 C6
             # yamllint disable-line rule:line-length
             options: --environment esp32c6-idf-tidy --grep SOC_LP_I2C_SUPPORTED --grep USE_ESP32_VARIANT_ESP32C6 --grep USE_OPENTHREAD --grep USE_ZIGBEE
+            tidy_environment: esp32c6-idf-tidy
 
     steps:
       - name: Check out code from GitHub
@@ -893,6 +912,11 @@ jobs:
       - name: Cache ESP-IDF install
         uses: ./.github/actions/cache-esp-idf
 
+      - name: Cache clang-tidy idedata
+        uses: ./.github/actions/cache-clang-tidy-idedata
+        with:
+          environment: ${{ matrix.tidy_environment }}
+
       - name: Register problem matchers
         run: |
           echo "::add-matcher::.github/workflows/matchers/gcc.json"