test(e2e): scaffold WebdriverIO + tauri-driver E2E testing infrastructure

v2/tests/e2e/README.md

@@ -5,26 +5,29 @@ The app runs inside WebKit2GTK on Linux, so tests interact with the real WebView
 
 ## Prerequisites
 
-- Built Tauri app (`npm run tauri build`)
-- Display server (X11 or Wayland) -- headless Xvfb works for CI
-- `tauri-driver` installed (`cargo install tauri-driver`)
-- WebdriverIO (`npm install --save-dev @wdio/cli @wdio/local-runner @wdio/mocha-framework`)
+- Rust toolchain (for building the Tauri app)
+- Display server (X11 or Wayland) — headless Xvfb works for CI
+- `tauri-driver` installed: `cargo install tauri-driver`
+- `webkit2gtk-driver` system package: `sudo apt install webkit2gtk-driver`
+- npm devDeps already in package.json (`@wdio/cli`, `@wdio/local-runner`, `@wdio/mocha-framework`, `@wdio/spec-reporter`)
 
 ## Running
 
 ```bash
-# Terminal 1: Start tauri-driver (bridges WebDriver to WebKit2GTK)
-tauri-driver
-
-# Terminal 2: Run tests
+# From v2/ directory — builds debug binary automatically, spawns tauri-driver
 npm run test:e2e
 ```
 
+The `wdio.conf.js` handles:
+1. Building the debug binary (`cargo tauri build --debug --no-bundle`) in `onPrepare`
+2. Spawning `tauri-driver` before each session
+3. Killing `tauri-driver` after each session
+
 ## CI setup (headless)
 
 ```bash
-# Install virtual framebuffer
-sudo apt install xvfb
+# Install virtual framebuffer + WebKit driver
+sudo apt install xvfb webkit2gtk-driver
 
 # Run with Xvfb wrapper
 xvfb-run npm run test:e2e
@@ -32,19 +35,35 @@ xvfb-run npm run test:e2e
 
 ## Writing tests
 
-Tests use WebdriverIO. Example:
+Tests use WebdriverIO with Mocha. Specs go in `specs/`:
 
 ```typescript
-import { browser } from '@wdio/globals';
+import { browser, expect } from '@wdio/globals';
 
 describe('BTerminal', () => {
-  it('should show the terminal pane on startup', async () => {
-    const terminal = await browser.$('.terminal-pane');
-    await expect(terminal).toBeDisplayed();
+  it('should show the status bar', async () => {
+    const statusBar = await browser.$('.status-bar');
+    await expect(statusBar).toBeDisplayed();
   });
 });
 ```
 
+Key constraints:
+- `maxInstances: 1` — Tauri doesn't support parallel WebDriver sessions
+- Mocha timeout is 60s — the app needs time to initialize
+- Tests interact with the real WebKit2GTK WebView, not a browser
+
+## File structure
+
+```
+tests/e2e/
+├── README.md          # This file
+├── wdio.conf.js       # WebdriverIO config with tauri-driver lifecycle
+├── tsconfig.json      # TypeScript config for test specs
+└── specs/
+    └── smoke.test.ts  # Basic smoke tests (app renders, sidebar toggle)
+```
+
 ## References
 
 - Tauri WebDriver docs: https://v2.tauri.app/develop/tests/webdriver/