Merge pull request #27 from woocommerce/fix/phpcs-diff-no-changes

Fix the JSON syntax error of running `phpcd-diff` action when no changes are made

packages/js/github-actions/actions/phpcs-diff/action.yml

@@ -33,12 +33,21 @@ runs:
       # a workflow to a pull request, it uses the revision of a merge commit to run the workflow
       # as well. Therefore, `git diff HEAD^...HEAD` includes all diffs of a PR.
       run: |
-        vendor/bin/diffFilter --phpcsStrict <(git diff HEAD^...HEAD) <(vendor/bin/phpcs ./* -q --report=json) --report=phpcs 0 > /tmp/phpcs-diff.json
+        JSON_REPORT="/tmp/phpcs-diff.json"
+        vendor/bin/diffFilter --phpcsStrict <(git diff HEAD^...HEAD) <(vendor/bin/phpcs ./* -q --report=json) --report=phpcs 0 > "$JSON_REPORT"
+
+        # It's a workaround that prevents the empty result from being passed as a JSON file to annotate-phpcs-report.js
+        # Related issue: https://github.com/exussum12/coverageChecker/issues/72
+        if [ ! -s "$JSON_REPORT" ]; then
+          echo "No changes."
+          exit 0
+        fi
+
         cd "${{ github.action_path }}"
-        node annotate-phpcs-report.js /tmp/phpcs-diff.json
+        node annotate-phpcs-report.js "$JSON_REPORT"
         cd -
 
-        TOTAL_ERRORS=$(jq ".totals.errors" /tmp/phpcs-diff.json)
+        TOTAL_ERRORS=$(jq ".totals.errors" "$JSON_REPORT"
         if [ "$TOTAL_ERRORS" != "0" ]; then
           exit 1
         fi