test: coverage ratchet + renderer hooks + main-process backfill

.github/workflows/ci.yml

@@ -34,8 +34,16 @@ jobs:
       - name: Typecheck (video)
         run: pnpm video:typecheck
 
-      - name: Unit tests
-        run: pnpm test
+      - name: Unit tests (coverage-gated)
+        run: pnpm test:coverage
+
+      - name: Coverage summary
+        if: always()
+        run: |
+          if [ -f coverage/coverage-summary.json ]; then
+            echo '### Coverage' >> "$GITHUB_STEP_SUMMARY"
+            node -e 'const t=require("./coverage/coverage-summary.json").total; for (const k of ["lines","statements","functions","branches"]) console.log(`- ${k}: ${t[k].pct}%`)' >> "$GITHUB_STEP_SUMMARY"
+          fi
 
       - name: Build
         run: pnpm build

.gitignore

@@ -1,6 +1,7 @@
 node_modules/
 out/
 dist/
+coverage/
 *.log
 .DS_Store
 .playwright-mcp/

CLAUDE.md

@@ -45,3 +45,18 @@ need changes for routine updates.
   for the inclusive breakpoints. The residual classes in globals.css
   (`lp-nav`, `reveal`, `lp-screen`, `blog-prose`, ...) are behavior hooks or
   markdown-facing; keep them stable.
+
+## Testing
+
+- Coverage is ratcheted: CI fails below the thresholds in `vitest.config.ts`.
+  CI's (Linux) numbers are authoritative — macOS measures slightly higher, so
+  don't copy local numbers. When a PR raises CI coverage, bump the thresholds
+  in the same PR; never lower them.
+- New logic ships with tests in the same PR. Renderer hook tests use the typed
+  bridge mock (`src/renderer/src/test/mock-clean-bridge.ts`); it is typed
+  against `CleanApi`, so preload API changes must update it (the compiler
+  will insist).
+- UI components (`.tsx`) are Storybook's responsibility — no component render
+  tests, and `.tsx` is excluded from coverage on purpose.
+- Two vitest projects: `node` (`src/main|shared|preload`) and `renderer`
+  (jsdom). Run one file with `pnpm vitest run --project <name> <path>`.

package.json

@@ -18,6 +18,7 @@
     "lint": "biome check .",
     "format": "biome format --write .",
     "test": "vitest run",
+    "test:coverage": "vitest run --coverage",
     "icon": "node scripts/make-icon.mjs",
     "demo": "node scripts/demo-data.mjs",
     "package": "electron-vite build && electron-builder --mac --dir",
@@ -30,18 +31,21 @@
   "devDependencies": {
     "@biomejs/biome": "2.5.0",
     "@remotion/cli": "^4.0.477",
+    "@testing-library/react": "^16.3.2",
     "@types/node": "^22.10.0",
     "@types/react": "^18.3.12",
     "@types/react-dom": "^18.3.1",
     "@types/semver": "^7.7.1",
     "@vitejs/plugin-react": "^4.3.4",
+    "@vitest/coverage-v8": "^3.2.7",
     "electron": "^33.2.0",
     "electron-builder": "^25.1.8",
     "electron-vite": "^2.3.0",
+    "jsdom": "^30.0.0",
     "remotion": "^4.0.477",
     "typescript": "^5.7.2",
     "vite": "^5.4.11",
-    "vitest": "^2.1.8"
+    "vitest": "^3.2.7"
   },
   "dependencies": {
     "electron-updater": "^6.8.9",