Shard the full E2E run and make CI-sensitive probes reproducible

.github/workflows/e2e.yml

@@ -16,6 +16,10 @@ on:
           - full
           - smoke
         default: full
+      grep:
+        description: Only the tests whose title matches this regular expression (overrides scope)
+        type: string
+        default: ''
 
 permissions:
   contents: read
@@ -47,18 +51,27 @@ jobs:
               - '!**/*.md'
 
   e2e:
-    name: E2E (${{ github.event_name == 'pull_request' && 'smoke' || inputs.scope || 'full' }})
+    name: E2E (${{ github.event_name == 'pull_request' && 'smoke' || inputs.scope || 'full' }}${{ matrix.shards > 1 && format(' {0}/{1}', matrix.shard, matrix.shards) || '' }})
     needs: changes
     # `changes` is skipped outside pull requests; run regardless of that, but only on a player change in a pull request.
     if: |
       always() &&
       (github.event_name != 'pull_request' || needs.changes.outputs.player == 'true')
     runs-on: ubuntu-24.04-arm
     timeout-minutes: ${{ github.event_name == 'pull_request' && 30 || 90 }}
+    # The 4-vCPU runner renders in software: several browsers at once space frames far enough apart that tests pressing
+    # keys at a time on the page miss their windows or race the end of a short chart (#792). The full run is split over
+    # four runners with one browser each; the smoke run stays on one runner with four.
+    strategy:
+      fail-fast: false
+      matrix:
+        shard: ${{ fromJSON((github.event_name == 'pull_request' || inputs.scope == 'smoke' || inputs.grep != '' && inputs.grep != null) && '[1]' || '[1, 2, 3, 4]') }}
+        shards: ${{ fromJSON((github.event_name == 'pull_request' || inputs.scope == 'smoke' || inputs.grep != '' && inputs.grep != null) && '[1]' || '[4]') }}
     env:
       CI: 'true'
-      E2E_WORKERS: 4
-      E2E_GREP: ${{ (github.event_name == 'pull_request' || inputs.scope == 'smoke') && '@smoke' || '' }}
+      E2E_WORKERS: ${{ (github.event_name == 'pull_request' || inputs.scope == 'smoke') && 4 || 1 }}
+      E2E_GREP: ${{ inputs.grep || ((github.event_name == 'pull_request' || inputs.scope == 'smoke') && '@smoke' || '') }}
+      E2E_SHARD: ${{ matrix.shard }}/${{ matrix.shards }}
 
     steps:
       - name: Checkout
@@ -83,17 +96,15 @@ jobs:
         shell: bash
         run: |
           set -euo pipefail
-          if [ -n "$E2E_GREP" ]; then
-            pnpm run test:e2e --grep "$E2E_GREP"
-          else
-            pnpm run test:e2e
-          fi
+          args=(--shard "$E2E_SHARD")
+          if [ -n "$E2E_GREP" ]; then args+=(--grep "$E2E_GREP"); fi
+          pnpm run test:e2e "${args[@]}"
 
       - name: Upload report
         if: failure() || cancelled()
         uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
         with:
-          name: e2e-report-${{ github.run_id }}
+          name: e2e-report-${{ github.run_id }}-${{ matrix.shard }}
           path: |
             packages/app-play/e2e-report/
             packages/app-play/e2e-results/

packages/app-play/e2e/bmson-generic.spec.ts

@@ -96,7 +96,9 @@ for (const family of ['native', 'canvas', 'lr2', 'beatoraja'] as const) {
           'bound F5 instead of restart',
         );
       const result = await player.waitForResult(0);
-      expect(result.results[0]!.judged.pgreat + result.results[0]!.judged.great).toBe(count === 70 ? 5 : 3);
+      // Every bound key hits its note; a slow CI frame can land a page-timed press in GOOD (#792).
+      const judged = result.results[0]!.judged;
+      expect(judged.pgreat + judged.great + judged.good).toBe(count === 70 ? 5 : 3);
       expect(result.results[0]!.judged.poor).toBe(0);
       const replay = await player.lastReplay();
       expect(replay?.chart.laneMode).toBe(`${count} KEY GENERIC`);

packages/app-play/e2e/bmson-zero-total.spec.ts

@@ -30,7 +30,9 @@ for (const family of ['native', 'canvas', 'lr2', 'beatoraja'] as const) {
     await player.waitForResult(0);
     const replay = await player.lastReplay();
     expect(replay?.play.bmsonTotalMode).toBe('spec');
-    expect((replay?.results?.native?.judge.pgreat ?? 0) + (replay?.results?.native?.judge.great ?? 0)).toBe(2);
+    // Both notes are hit; a slow CI frame can land a page-timed press in GOOD (#792).
+    const judge = replay?.results?.native?.judge;
+    expect((judge?.pgreat ?? 0) + (judge?.great ?? 0) + (judge?.good ?? 0)).toBe(2);
     expect(replay?.results?.native?.gauge.final).toBe(20);
     if (family === 'native') {
       await player.leaveResult();

packages/app-play/e2e/chart-text.spec.ts

@@ -16,7 +16,8 @@ async function textPixels(player: Player): Promise<number> {
       for (let y = 0; y < image.height * 0.35; y++)
         for (let x = image.width * 0.1; x < image.width * 0.9; x++) {
           const offset = (y * image.width + Math.floor(x)) * 4;
-          if (data[offset]! > 235 && data[offset + 1]! > 235 && data[offset + 2]! > 235) count++;
+          // Bright, not pure white: Linux renders the thin text with fewer fully white pixels (#792).
+          if (data[offset]! > 160 && data[offset + 1]! > 160 && data[offset + 2]! > 160) count++;
         }
       return count;
     },
@@ -45,6 +46,7 @@ for (const family of ['native', 'canvas', 'lr2', 'beatoraja'] as const) {
     const before = await textPixels(player);
     await player.waitFor((state) => (state.play?.seconds ?? 0) > 2.2, 'text selection');
     await expect.poll(() => textPixels(player), { timeout: 2000, intervals: [100] }).toBeGreaterThan(before + 500);
+    const shown = await textPixels(player);
     await player.key('Space');
     const paused = (await player.state()).play?.seconds;
     await player.page.screenshot({ path: info.outputPath('chart-text.png') });
@@ -53,7 +55,8 @@ for (const family of ['native', 'canvas', 'lr2', 'beatoraja'] as const) {
     expect((await player.state()).play?.seconds).toBeCloseTo(paused!, 2);
     await player.key('Space');
     await player.waitFor((state) => (state.play?.seconds ?? 0) > 6.2, 'text clear');
-    await expect.poll(() => textPixels(player), { timeout: 2000, intervals: [100] }).toBeLessThan(before + 300);
+    // Cleared: back nearer the empty count than the shown one (other HUD text keeps changing).
+    await expect.poll(() => textPixels(player), { timeout: 2000, intervals: [100] }).toBeLessThan((before + shown) / 2);
     if (family === 'native') await expect(player.page.locator('[data-chart-text]')).toBeHidden();
   });
 }

packages/app-play/e2e/course-maker.spec.ts

@@ -34,6 +34,8 @@ async function downloadedText(download: Download): Promise<string> {
 }
 
 test('makes, saves, cancels, renames, deletes and exports courses', async ({ player }) => {
+  // Hundreds of UI steps: the CI runner spends seconds per click (#792).
+  test.setTimeout(360_000);
   const { page } = player;
   await openWithLibrary(player);
   const card = page.locator('aside.course-maker-card');