Add GitHub workflow for automatically updating index.js

.eslintignore

@@ -1,3 +1,4 @@
 dist/
+action/
 lib/
-node_modules/
+node_modules/

.github/workflows/check-dist.yml

@@ -1,51 +0,0 @@
-# `dist/index.js` is a special file in Actions.
-# When you reference an action with `uses:` in a workflow,
-# `index.js` is the code that will run.
-# For our project, we generate this file through a build process from other source files.
-# We need to make sure the checked-in `index.js` actually matches what we expect it to be.
-name: Check dist directory
-
-on:
-  push:
-    branches:
-      - main
-      - releases/**
-    paths-ignore:
-      - '**.md'
-  pull_request:
-    paths-ignore:
-      - '**.md'
-  workflow_dispatch:
-
-jobs:
-  check-dist:
-    runs-on: ubuntu-latest
-
-    steps:
-      - uses: actions/checkout@v4
-
-      - uses: actions/setup-node@v4
-        with:
-          node-version: 20
-      - name: Build
-        run: |
-          npm -v
-          node -v
-          npm clean-install
-          npm run build
-
-      - name: Compare the expected and actual dist/ directories
-        run: |
-          if [ "$(git diff --ignore-space-at-eol dist/ | wc -l)" -gt "0" ]; then
-            echo "Detected uncommitted changes after build.  See status below:"
-            git diff
-            exit 1
-          fi
-        id: diff
-
-      # If index.js was different than expected, upload the expected version as an artifact
-      - uses: actions/upload-artifact@v4
-        if: ${{ failure() && steps.diff.conclusion == 'failure' }}
-        with:
-          name: dist
-          path: dist/

.github/workflows/check-pull-request-no-dist-change.yml

@@ -0,0 +1,22 @@
+# Pull request authors are not expected to update `action/index.js` themselves
+name: Check no dist update
+on:
+  pull_request:
+    # For simplicity determine if the file was changed using `paths` here (instead of running any diff command below)
+    # There are some limitations to this, but they most likely won't cause any issues here
+    # https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#git-diff-comparisons
+    paths:
+      - 'action/index.js'
+
+jobs:
+  check-no-dist-update:
+    name: Check no dist update
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Check no dist update
+      # Fail unconditionally; this workflow is only run if the file has changed, see
+      # condition at the start of this file
+      run: |
+        echo "Pull requests should not update 'action/index.js'"
+        exit 1

.github/workflows/ci.yml

@@ -36,13 +36,13 @@ jobs:
       with:
         node-version: 20
 
-    - name: Build action (pull request)
-      # Pull requests are not expected to update `dist/index.js` themselves; therefore build `dist/index.js`
-      # here before running integration test
-      if: github.event_name == 'pull_request'
+    - name: Build action
+      # Pull requests are not expected to update `action/index.js`, and pushes to the `main` branch
+      # might not have updated the file either (and rely on CI to do that), therefore build the
+      # action here first
       run: |
         npm clean-install
-        npm run build
+        npm run github_ci_all
 
     - name: Run wrapper-validation-action
       id: action-test
@@ -76,13 +76,13 @@ jobs:
       with:
         node-version: 20
 
-    - name: Build action (pull request)
-      # Pull requests are not expected to update `dist/index.js` themselves; therefore build `dist/index.js`
-      # here before running integration test
-      if: github.event_name == 'pull_request'
+    - name: Build action
+      # Pull requests are not expected to update `action/index.js`, and pushes to the `main` branch
+      # might not have updated the file either (and rely on CI to do that), therefore build the
+      # action here first
       run: |
         npm clean-install
-        npm run build
+        npm run github_ci_all
 
     - name: Run wrapper-validation-action
       id: action-test

.github/workflows/update-dist.yml

@@ -0,0 +1,50 @@
+name: Update `action/index.js`
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  update-dist:
+    runs-on: ubuntu-latest
+
+    permissions:
+      # Allow the job to push the changed file to the repository
+      contents: write
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Set up Node.js
+      uses: actions/setup-node@v4
+      with:
+        node-version: 20
+        cache: npm
+
+    - name: Build and test
+      run: |
+        npm -v
+        node -v
+        npm clean-install
+        npm run github_ci_all
+
+    # To be safe, verify that either there are no changes or only `action/index.js` has changed
+    - name: Verify no unexpected changes
+      run: |
+        # Check for changes to any file other than `action/index.js`,
+        # see https://stackoverflow.com/a/29374503
+        # Note that this does not detect new untracked files
+        if ! git diff --exit-code --quiet -- . ':!action/index.js'; then
+          echo "Unexpected changes:"
+          git diff -- . ':!action/index.js'
+          exit 1
+        fi
+
+    # Commit and push changes; has no effect if the file did not change
+    # Important: The push event will not trigger any other workflows, see
+    # https://github.com/stefanzweifel/git-auto-commit-action?tab=readme-ov-file#commits-made-by-this-action-do-not-trigger-new-workflow-runs
+    - name: Commit & push changes
+      uses: stefanzweifel/git-auto-commit-action@v5
+      with:
+        commit_message: 'Update `action/index.js`'
+        file_pattern: 'action/index.js'

.gitignore

@@ -100,3 +100,7 @@ lib/**/*
 
 .idea/
 *.iml
+
+# Ignore `index.js` file created during build; it is copied by CI to a separate directory
+# Otherwise authors of PRs would commit it, causing merge conflicts or erroneous merges
+/dist

.prettierignore

@@ -1,3 +1,4 @@
 dist/
+action/
 lib/
-node_modules/
+node_modules/

RELEASING.md

@@ -1,9 +1,10 @@
 # Release
 
 * starting on `main`
-* `npm install`
+* `npm clean-install`
 * `npm run all`
-* Commit and push any changes to the `dist` directory. Wait for CI.
+* verify that `dist/index.js` matches `action/index.js`
+* if not, commit and push the changes, then wait for CI to finish
 * `git tag v1.0.x && git push --tags` with the actual version number
 * `git tag -f -a v1 && git push -f --tags`
 * go to https://github.com/gradle/wrapper-validation-action/releases

action.yml

@@ -22,7 +22,7 @@ outputs:
 
 runs:
   using: 'node20'
-  main: 'dist/index.js'
+  main: 'action/index.js'
 
 branding:
   icon: 'shield'

package.json

@@ -12,7 +12,8 @@
     "compile": "ncc build",
     "test": "jest",
     "build": "npm run check && npm run compile",
-    "all": "npm run build && npm test"
+    "all": "npm run build && npm test",
+    "github_ci_all": "npm run all && cp dist/index.js action/index.js"
   },
   "repository": {
     "type": "git",