Run tests and compare results on PRs. (#181)

.github/workflows/gh-pages.yml

@@ -1,11 +1,16 @@
-name: Deploy site to Pages
+name: Build and test
 
 on:
   # Runs on pushes targeting the default branch
   push:
     branches:
       - master
       - main
+  pull_request:
+    branches:
+      - master
+      - main
+
   workflow_dispatch:
 
 # Sets permissions of the GITHUB_TOKEN to allow deployment to GitHub Pages
@@ -46,8 +51,9 @@ jobs:
       - name: WPT hosts
         run: "./test/wpt/wpt make-hosts-file | sudo tee -a /etc/hosts"
       - name: WPT tests
-        continue-on-error: true
         run: "npm run test:wpt"
+      - name: Expected results
+        run: "npm run test:compare"
       - name: Clean build files
         run: "rm -rf node_modules test/wpt"
       - name: Upload artifact
@@ -62,6 +68,7 @@ jobs:
       url: ${{ steps.deployment.outputs.page_url }}
     runs-on: ubuntu-latest
     needs: build
+    if: github.event_name == 'push'
     steps:
       - name: Deploy to GitHub Pages
         id: deployment

package.json

@@ -9,8 +9,9 @@
     "dev": "run-all \"serve\" \" microbundle watch -f iife \"",
     "deploy": "npm run build",
     "test-setup": "node test/setup/checkout-wpt.mjs",
-    "test:wpt": "npm run test-setup && cd test && cd wpt && python wpt run --headless -y --log-wptreport ../report/data.json --log-wptscreenshot=../report/screenshots.txt --log-html=../report/index.html --inject-script ../../dist/scroll-timeline.js firefox scroll-animations",
-    "test:simple": "npm run test-setup && cd test && cd wpt && python wpt serve --inject-script ../../dist/scroll-timeline.js"
+    "test:wpt": "npm run test-setup && cd test && cd wpt && (python wpt run --headless -y --log-wptreport ../report/data.json --log-wptscreenshot=../report/screenshots.txt --log-html=../report/index.html --inject-script ../../dist/scroll-timeline.js firefox scroll-animations || true)",
+    "test:simple": "npm run test-setup && cd test && cd wpt && python wpt serve --inject-script ../../dist/scroll-timeline.js",
+    "test:compare": "node test/summarize-json.mjs test/report/data.json > test/report/summary.txt && echo 'Comparing test results. If different and expected, patch the following diff to test/expected.txt:' && diff test/expected.txt test/report/summary.txt"
   },
   "repository": {
     "type": "git",