Improve full-ci label implementation with better output handling and UX

This commit enhances the /run-skipped-ci feature based on code review feedback:

**Critical Fixes:**
- Fix GitHub Actions output encoding to use explicit string values
- Add result-encoding: string to all label check steps
- Return 'true'/'false' strings instead of booleans for consistent shell comparison
- Fixes potential silent failures in label detection across 6 workflow files

**New Features:**
- Add automatic full-ci label cleanup when PRs are merged
- Add welcome message to new PRs explaining CI control commands
- Comprehensive documentation in CONTRIBUTING.md

**Files Changed:**
- .github/workflows/main.yml - Fixed output encoding
- .github/workflows/examples.yml - Fixed output encoding
- .github/workflows/pro-*.yml (3 files) - Fixed output encoding
- .github/workflows/cleanup-full-ci-label.yml - New: Auto-remove label on merge
- .github/workflows/pr-welcome-message.yml - New: Welcome message for PRs
- CONTRIBUTING.md - Added CI Control Commands documentation

The full-ci label now persists correctly across commits and provides clear
user guidance through automated messages.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: justin808

.github/workflows/cleanup-full-ci-label.yml

@@ -0,0 +1,35 @@
+name: Cleanup full-ci label on PR merge
+
+on:
+  pull_request:
+    types: [closed]
+
+jobs:
+  remove-label:
+    # Only run when PR is actually merged (not just closed)
+    if: github.event.pull_request.merged == true
+    runs-on: ubuntu-22.04
+    permissions:
+      issues: write
+      pull-requests: write
+    steps:
+      - name: Remove full-ci label
+        uses: actions/github-script@v7
+        with:
+          script: |
+            try {
+              await github.rest.issues.removeLabel({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: context.issue.number,
+                name: 'full-ci'
+              });
+              console.log('✅ Removed full-ci label from merged PR');
+            } catch (error) {
+              if (error.status === 404) {
+                console.log('ℹ️  Label not present - nothing to clean up');
+              } else {
+                console.error('⚠️  Failed to remove label:', error.message);
+                // Don't fail the workflow - this is just cleanup
+              }
+            }

.github/workflows/examples.yml

@@ -40,10 +40,11 @@ jobs:
         id: check-label
         uses: actions/github-script@v7
         with:
+          result-encoding: string
           script: |
             // Only check labels on pull requests
             if (!context.payload.pull_request) {
-              return false;
+              return 'false';
             }
 
             const { data: labels } = await github.rest.issues.listLabelsOnIssue({
@@ -54,7 +55,7 @@ jobs:
 
             const hasLabel = labels.some(label => label.name === 'full-ci');
             console.log(`full-ci label present: ${hasLabel}`);
-            return hasLabel;
+            return hasLabel ? 'true' : 'false';
       - name: Detect relevant changes
         id: detect
         run: |

.github/workflows/main.yml

@@ -40,10 +40,11 @@ jobs:
         id: check-label
         uses: actions/github-script@v7
         with:
+          result-encoding: string
           script: |
             // Only check labels on pull requests
             if (!context.payload.pull_request) {
-              return false;
+              return 'false';
             }
 
             const { data: labels } = await github.rest.issues.listLabelsOnIssue({
@@ -54,7 +55,7 @@ jobs:
 
             const hasLabel = labels.some(label => label.name === 'full-ci');
             console.log(`full-ci label present: ${hasLabel}`);
-            return hasLabel;
+            return hasLabel ? 'true' : 'false';
       - name: Detect relevant changes
         id: detect
         run: |

.github/workflows/pr-welcome-message.yml

@@ -0,0 +1,45 @@
+name: PR Welcome Message
+
+on:
+  pull_request:
+    types: [opened]
+
+jobs:
+  welcome:
+    runs-on: ubuntu-22.04
+    permissions:
+      issues: write
+      pull-requests: write
+    steps:
+      - name: Post welcome message
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const welcomeMessage = [
+              '👋 **Thanks for your contribution!**',
+              '',
+              'This PR will run CI tests based on the files you changed. If some tests are skipped and you want to run the full test suite (including minimum dependency tests), you can use these commands:',
+              '',
+              '### CI Control Commands',
+              '',
+              '- **`/run-skipped-ci`** - Runs all skipped CI checks and enables full CI mode for this PR',
+              '  - Adds the `full-ci` label to ensure future commits also run the full test suite',
+              '  - Useful when you want comprehensive testing across all configurations',
+              '',
+              '- **`/stop-run-skipped-ci`** - Disables full CI mode and returns to standard CI',
+              '  - Removes the `full-ci` label',
+              '  - Future commits will only run tests for changed files',
+              '',
+              '💡 **Note:** The `full-ci` label will be automatically removed when this PR is merged.',
+              '',
+              'View CI progress in the [Actions tab](${context.serverUrl}/${context.repo.owner}/${context.repo.repo}/actions).'
+            ].join('\n');
+
+            await github.rest.issues.createComment({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              issue_number: context.issue.number,
+              body: welcomeMessage
+            });
+
+            console.log('✅ Posted welcome message to PR');

.github/workflows/pro-integration-tests.yml

@@ -34,10 +34,11 @@ jobs:
         id: check-label
         uses: actions/github-script@v7
         with:
+          result-encoding: string
           script: |
             // Only check labels on pull requests
             if (!context.payload.pull_request) {
-              return false;
+              return 'false';
             }
 
             const { data: labels } = await github.rest.issues.listLabelsOnIssue({
@@ -48,7 +49,7 @@ jobs:
 
             const hasLabel = labels.some(label => label.name === 'full-ci');
             console.log(`full-ci label present: ${hasLabel}`);
-            return hasLabel;
+            return hasLabel ? 'true' : 'false';
       - name: Detect relevant changes
         id: detect
         working-directory: .

.github/workflows/pro-lint.yml

@@ -34,10 +34,11 @@ jobs:
         id: check-label
         uses: actions/github-script@v7
         with:
+          result-encoding: string
           script: |
             // Only check labels on pull requests
             if (!context.payload.pull_request) {
-              return false;
+              return 'false';
             }
 
             const { data: labels } = await github.rest.issues.listLabelsOnIssue({
@@ -48,7 +49,7 @@ jobs:
 
             const hasLabel = labels.some(label => label.name === 'full-ci');
             console.log(`full-ci label present: ${hasLabel}`);
-            return hasLabel;
+            return hasLabel ? 'true' : 'false';
       - name: Detect relevant changes
         id: detect
         working-directory: .

.github/workflows/pro-package-tests.yml

@@ -34,10 +34,11 @@ jobs:
         id: check-label
         uses: actions/github-script@v7
         with:
+          result-encoding: string
           script: |
             // Only check labels on pull requests
             if (!context.payload.pull_request) {
-              return false;
+              return 'false';
             }
 
             const { data: labels } = await github.rest.issues.listLabelsOnIssue({
@@ -48,7 +49,7 @@ jobs:
 
             const hasLabel = labels.some(label => label.name === 'full-ci');
             console.log(`full-ci label present: ${hasLabel}`);
-            return hasLabel;
+            return hasLabel ? 'true' : 'false';
       - name: Detect relevant changes
         id: detect
         working-directory: .

CONTRIBUTING.md

@@ -421,6 +421,55 @@ The CI system intelligently skips unnecessary work:
 
 For more details, see [`docs/CI_OPTIMIZATION.md`](./docs/CI_OPTIMIZATION.md).
 
+### CI Control Commands
+
+React on Rails provides PR comment commands to control CI behavior:
+
+#### `/run-skipped-ci` - Enable Full CI Mode
+
+Runs all skipped CI checks and enables full CI mode for the PR:
+
+```
+/run-skipped-ci
+```
+
+**What it does:**
+
+- Triggers all CI workflows that were skipped due to unchanged code
+- Adds the `full-ci` label to the PR
+- **Persists across future commits** - all subsequent pushes will run the full test suite
+- Runs minimum dependency tests (Ruby 3.2, Node 20, Shakapacker 8.2.0, React 18)
+
+**When to use:**
+
+- You want comprehensive testing across all configurations
+- Testing changes that might affect minimum supported versions
+- Validating generator changes or core functionality
+- Before merging PRs that touch critical paths
+
+#### `/stop-run-skipped-ci` - Disable Full CI Mode
+
+Removes the `full-ci` label and returns to standard CI behavior:
+
+```
+/stop-run-skipped-ci
+```
+
+**What it does:**
+
+- Removes the `full-ci` label from the PR
+- Future commits will use the optimized CI suite (tests only changed code)
+- Does not stop currently running workflows
+
+**When to use:**
+
+- You've validated changes with full CI and want to return to faster feedback
+- Reducing CI time during rapid iteration on a PR
+
+#### Automatic Cleanup
+
+The `full-ci` label is automatically removed when a PR is merged, so you don't need to manually clean it up.
+
 ### Install Generator
 
 In your Rails app add this gem with a path to your fork.