👷 (PlatformIO): Skip if no code was changed

Author: leon0399

Diff for: .github/workflows/ci.yml

@@ -6,13 +6,15 @@ on:
       - main
       - master
       - develop
+      - feature/mpu6050
     paths-ignore:
       - "**/*.md"
   push:
     branches:
       - main
       - master
       - develop
+      - feature/mpu6050
     paths-ignore:
       - "**/*.md"
 
@@ -31,7 +33,36 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
+      # We will skip the build if there are no changes in the examples or src folder
+      - name: Get changed files
+        id: changed-files
+        uses: tj-actions/changed-files@v44
+        with:
+          files: |
+            "examples/**/*.ino"
+            "src/**/*"
+
+      - name: Extract device name
+        id: device
+        run: |
+          # get 2nd element from the example path as lowercase
+          DEVICE=$(echo "${{ matrix.example }}" | cut -d'/' -f2 | tr '[:upper:]' '[:lower:]')
+          echo "device=$DEVICE" >> "$GITHUB_OUTPUT"
+
+      - name: Check if the build is necessary
+        id: should-build
+        run: |
+          if [ -z "${{ steps.changed-files.outputs.all_modified_files }}" ]; then
+            echo "No changes in the examples or src folder. Skipping the build."
+            echo "should_build=false" >> "$GITHUB_OUTPUT"
+          else
+            # todo: check device name with changed files
+            echo "Changes detected in the examples or src folder. Proceeding with the build."
+            echo "should_build=true" >> "$GITHUB_OUTPUT"
+          fi
+
       - name: Cache pip
+        if : ${{ steps.should-build.outputs.should_build == 'true' }}
         uses: actions/cache@v4
         with:
           path: ~/.cache/pip
@@ -40,6 +71,7 @@ jobs:
             ${{ runner.os }}-pip-
 
       - name: Cache PlatformIO
+        if : ${{ steps.should-build.outputs.should_build == 'true' }}
         uses: actions/cache@v4
         with:
           path: |
@@ -50,18 +82,21 @@ jobs:
             ${{ runner.os }}-pio-
 
       - name: Set up Python
+        if : ${{ steps.should-build.outputs.should_build == 'true' }}
         uses: actions/setup-python@v5
         with:
           python-version: "3.9"
 
       - name: Install PlatformIO
+        if : ${{ steps.should-build.outputs.should_build == 'true' }}
         run: |
           python -m pip install --upgrade pip
           pip install --upgrade platformio
           pio upgrade --dev
           pio pkg update --global
 
       - name: Build example
+        if : ${{ steps.should-build.outputs.should_build == 'true' }}
         run: |
           pio ci --lib="." --board=${{ join(matrix.boards, ' --board=') }}
         env: