feat: Enable GH visual regression test action (#12)

.github/workflows/visual-regression.yml

@@ -0,0 +1,60 @@
+name: Visual Regressions
+
+on:
+  pull_request:
+    branches:
+      - main
+  push:
+    branches:
+      - main
+
+env:
+  VISUAL_REGRESSION_SNAPSHOT_DIRECTORY: "__image_snapshots__"
+
+jobs:
+  test:
+    name: Run Tests
+    runs-on: ubuntu-latest
+    if: github.event.ref != 'refs/heads/main'
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v3
+        with:
+          node-version: 18
+          cache: "npm"
+      - name: "Download artifacts"
+        # Turns out you can not use artifacts from a previous workflow run.
+        # I'm reluctant to check in the resulting screenshots into the repository,
+        # which is why we use the following hack, until it's solved on Github side:
+        # https://github.com/actions/download-artifact/issues/3
+        run: |
+          RUN_ID=`gh run --repo $GITHUB_REPOSITORY --branch main list --workflow "Visual Regressions" --json databaseId --jq .[0].databaseId`
+          echo "Downloading snapshots created in run ${RUN_ID}"
+          gh run --repo $GITHUB_REPOSITORY download ${RUN_ID} -n "visual-regression-snapshots" -D ${{ env.VISUAL_REGRESSION_SNAPSHOT_DIRECTORY }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      - run: npm install
+      - run: npm run build
+      - run: npm run test:visual
+      - uses: actions/upload-artifact@v3
+        if: always()
+        with:
+          name: visual-regression-snapshots-results
+          path: ${{ env.VISUAL_REGRESSION_SNAPSHOT_DIRECTORY }}
+  update:
+    name: Update Snapshots
+    runs-on: ubuntu-latest
+    if: github.event.ref == 'refs/heads/main'
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v3
+        with:
+          node-version: 18
+          cache: "npm"
+      - run: npm install
+      - run: npm run build
+      - run: npm run test:visual:update
+      - uses: actions/upload-artifact@v3
+        with:
+          name: visual-regression-snapshots
+          path: ${{ env.VISUAL_REGRESSION_SNAPSHOT_DIRECTORY }}

vite.e2e-visual.config.mjs

@@ -2,7 +2,7 @@
 // SPDX-License-Identifier: Apache-2.0
 import process from "node:process";
 import { defineConfig } from "vite";
-import base from "./vite.config.js";
+import base from "./vite.config.mjs";
 
 // https://vitejs.dev/config/
 export default defineConfig({