pr-checklist-validator.yml

name: PR Checklist Validator

on:
  pull_request:
    types: [opened, edited, synchronize, reopened]

jobs:
  validate-checklist:
    runs-on: ubuntu-latest
    name: Validate PR Checklist
    
    steps:
      - name: Check PR Checklist
        uses: actions/github-script@v7
        with:
          script: |
            const prBody = context.payload.pull_request.body || '';
            
            // Find all checkboxes in the PR body
            const checkboxRegex = /- \[([ xX])\]/g;
            const checkboxes = [...prBody.matchAll(checkboxRegex)];
            
            if (checkboxes.length === 0) {
              core.setFailed('❌ No checkboxes found in PR description. Please use the PR template.');
              return;
            }
            
            // Count checked and unchecked boxes
            const totalBoxes = checkboxes.length;
            const checkedBoxes = checkboxes.filter(match => 
              match[1].toLowerCase() === 'x'
            ).length;
            const uncheckedBoxes = totalBoxes - checkedBoxes;
            
            // Check for Linear URL/ticket
            const linearRegex = /\*\*Linear ticket:\*\*[ \t]*([^\n]+)/i;
            const linearMatch = prBody.match(linearRegex);
            let linearError = null;
            
            if (!linearMatch) {
              linearError = '❌ Linear ticket field not found in PR description';
            } else {
              const linearValue = linearMatch[1].trim();
              // Check if it's still the placeholder or empty
              if (!linearValue || linearValue === 'PRO-XXX' || linearValue === '') {
                linearError = '❌ Linear ticket is not filled out (still showing placeholder "PRO-XXX")';
              } else {
                // Validate format: should be either a ticket ID (e.g., PRO-123) or a full Linear URL
                const validLinearPattern = /^(?:https?:\/\/linear\.app\/[^\s]+|[A-Z]+-\d+)$/;
                if (!validLinearPattern.test(linearValue)) {
                  linearError = `❌ Linear ticket format is invalid: "${linearValue}" (expected format: PRO-123 or https://linear.app/...)`;
                }
              }
            }
            
            // Create a summary
            core.summary
              .addHeading('PR Checklist Validation Results')
              .addRaw(`Total checkboxes: ${totalBoxes}`)
              .addRaw(`\nChecked: ✅ ${checkedBoxes}`)
              .addRaw(`\nUnchecked: ❌ ${uncheckedBoxes}`)
              .addRaw(`\nLinear ticket: ${linearError ? '❌ Invalid' : '✅ Valid'}`)
              .write();
            
            // Log the results
            console.log(`Total checkboxes: ${totalBoxes}`);
            console.log(`Checked: ${checkedBoxes}`);
            console.log(`Unchecked: ${uncheckedBoxes}`);
            console.log(`Linear validation: ${linearError || 'Valid'}`);
            
            // Collect all errors
            const errors = [];
            
            if (uncheckedBoxes > 0) {
              errors.push(
                `📊 Status: ${checkedBoxes}/${totalBoxes} items checked\n` +
                `⚠️  Please check all ${uncheckedBoxes} remaining checkbox(es) in the PR description before merging.`
              );
            }
            
            if (linearError) {
              errors.push(`🔗 ${linearError}\n⚠️  Please add a valid Linear ticket (e.g., PRO-123 or full Linear URL).`);
            }
            
            // Fail if there are any errors
            if (errors.length > 0) {
              core.setFailed(
                `❌ PR validation failed!\n\n` +
                errors.join('\n\n') +
                `\n\n💡 Tip: Review each section carefully and ensure all requirements are met.`
              );
            } else {
              console.log('✅ All checklist items are complete!');
              core.notice('✅ All checklist items are complete! PR is ready for review.');
            }
      
      - name: Comment on PR (if incomplete)
        if: failure()
        uses: actions/github-script@v7
        with:
          script: |
            const prBody = context.payload.pull_request.body || '';
            const checkboxes = [...prBody.matchAll(/- \[([ xX])\]/g)];
            const totalBoxes = checkboxes.length;
            const checkedBoxes = checkboxes.filter(match => 
              match[1].toLowerCase() === 'x'
            ).length;
            const uncheckedBoxes = totalBoxes - checkedBoxes;
            
            // Check Linear ticket
            const linearRegex = /\*\*Linear ticket:\*\*[ \t]*([^\n]+)/i;
            const linearMatch = prBody.match(linearRegex);
            let linearError = null;
            
            if (!linearMatch) {
              linearError = 'Linear ticket field not found';
            } else {
              const linearValue = linearMatch[1].trim();
              if (!linearValue || linearValue === 'PRO-XXX' || linearValue === '') {
                linearError = 'Linear ticket is still showing placeholder "PRO-XXX"';
              } else {
                const validLinearPattern = /^(?:https?:\/\/linear\.app\/[^\s]+|[A-Z]+-\d+)$/;
                if (!validLinearPattern.test(linearValue)) {
                  linearError = `Linear ticket format is invalid: "${linearValue}"`;
                }
              }
            }
            
            // Check if we already commented
            const { data: comments } = await github.rest.issues.listComments({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.payload.pull_request.number,
            });
            
            const botComment = comments.find(comment => 
              comment.user && comment.user.type === 'Bot' && 
              comment.body.includes('PR Checklist Validation')
            );
            
            const issues = [];
            if (totalBoxes === 0) {
              issues.push(`- ❌ **Checklist:** No checkboxes found. Please use the PR template.`);
            } else if (uncheckedBoxes > 0) {
              issues.push(`- ❌ **Checklist:** ${checkedBoxes}/${totalBoxes} items checked (${uncheckedBoxes} remaining)`);
            }
            if (linearError) {
              issues.push(`- ❌ **Linear ticket:** ${linearError}`);
            }
            
            // Build steps dynamically with correct numbering
            let stepNum = 1;
            const steps = [`${stepNum++}. Review the PR description`];
            
            if (totalBoxes === 0) {
              steps.push(`${stepNum++}. Use the PR template to add the required checklist`);
            } else if (uncheckedBoxes > 0) {
              steps.push(`${stepNum++}. Check all applicable boxes (\`- [x]\`)`);
              steps.push(`${stepNum++}. If an item doesn't apply, check it and add a note explaining why`);
            }
            
            if (linearError) {
              steps.push(`${stepNum++}. Add a valid Linear ticket (format: \`PRO-123\` or \`https://linear.app/...\`)`);
            }
            
            steps.push(`${stepNum}. Push an update or edit the PR description to re-trigger this check`);
            
            const commentBody = [
              '## 📋 PR Checklist Validation Failed',
              '',
              '⚠️ This PR cannot be merged until the following issues are resolved:',
              '',
              ...issues,
              '',
              '### What to do:',
              ...steps,
              '',
              '---',
              '*This check ensures all PR requirements are met before merging. If you believe this check should not apply to your PR, please discuss with the team.*'
            ].join('\n');
            
            if (botComment) {
              // Update existing comment
              await github.rest.issues.updateComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                comment_id: botComment.id,
                body: commentBody
              });
            } else {
              // Create new comment
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: context.payload.pull_request.number,
                body: commentBody
              });
            }
      
      - name: Comment on PR (if complete)
        if: success()
        uses: actions/github-script@v7
        with:
          script: |
            const prBody = context.payload.pull_request.body || '';
            const checkboxes = [...prBody.matchAll(/- \[([ xX])\]/g)];
            const totalBoxes = checkboxes.length;
            const checkedBoxes = checkboxes.filter(match => 
              match[1].toLowerCase() === 'x'
            ).length;
            
            // Check if we already commented
            const { data: comments } = await github.rest.issues.listComments({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.payload.pull_request.number,
            });
            
            const botComment = comments.find(comment => 
              comment.user && comment.user.type === 'Bot' && 
              comment.body.includes('PR Checklist Validation')
            );
            
            const commentBody = [
              '## ✅ PR Checklist Validation Passed',
              '',
              `**Status:** All ${totalBoxes} checklist items completed`,
              '**Linear ticket:** Valid ✅',
              '',
              '🎉 This PR meets all requirements and is ready for review!',
              '',
              '---',
              '*This validation ensures all PR requirements are met before merging.*'
            ].join('\n');
            
            if (botComment) {
              // Update existing comment with success message
              await github.rest.issues.updateComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                comment_id: botComment.id,
                body: commentBody
              });
            } else {
              // Create new success comment
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: context.payload.pull_request.number,
                body: commentBody
              });
            }