fix(screen-recorder): validate outputPath before rimraf

- Reject outputPath values that don't end with .mp4, since the hardcoded
  ffmpeg args (-movflags +faststart, libx264) only produce valid MP4 output
- Guard getVideoPath() with fs.stat to ensure the path resolves to a
  regular file before it can be passed to rimraf, preventing accidental
  deletion of directories or unrelated files
- Add e2e tests: valid outputPath persists on disk after stop, invalid
  extension is rejected with an explanatory error message

Author: yuri-schwab

lib/commands/extension.ts

@@ -1,7 +1,7 @@
 import { W3C_ELEMENT_KEY, errors } from '@appium/base-driver';
 import { Element, Rect } from '@appium/types';
 import { tmpdir } from 'node:os';
-import { join } from 'node:path';
+import { extname, join } from 'node:path';
 import { POWER_SHELL_FEATURE } from '../constants';
 import { NovaWindowsDriver } from '../driver';
 import { ClickType, Enum, Key } from '../enums';
@@ -693,6 +693,14 @@ export async function startRecordingScreen(this: NovaWindowsDriver, args?: {
     }
     this._screenRecorder = null;
 
+    if (outputPath) {
+        const ext = extname(outputPath).toLowerCase();
+        if (ext !== `.${DEFAULT_EXT}`) {
+            throw new errors.InvalidArgumentError(
+                `outputPath must be a path to a .${DEFAULT_EXT} file, got: '${outputPath}'`,
+            );
+        }
+    }
     const videoPath = outputPath ?? join(tmpdir(), `novawindows-recording-${Date.now()}.${DEFAULT_EXT}`);
     this._screenRecorder = new ScreenRecorder(videoPath, this.log, {
         fps: fps !== undefined ? parseInt(String(fps), 10) : undefined,

lib/commands/screen-recorder.ts

@@ -95,7 +95,16 @@ export class ScreenRecorder {
     }
 
     async getVideoPath(): Promise<string> {
-        return (await fs.exists(this._videoPath)) ? this._videoPath : '';
+        if (!(await fs.exists(this._videoPath))) {
+            return '';
+        }
+        const stat = await fs.stat(this._videoPath);
+        if (!stat.isFile()) {
+            throw new Error(
+                `The video path '${this._videoPath}' does not point to a regular file and will not be deleted`,
+            );
+        }
+        return this._videoPath;
     }
 
     isRunning(): boolean {

test/e2e/extension-screen-recording.e2e.ts

@@ -1,3 +1,6 @@
+import { existsSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
 import { describe, expect, it, beforeEach, afterEach } from 'vitest';
 import type { Browser } from 'webdriverio';
 import { createCalculatorSession, quitSession, resetCalculator } from './helpers/session.js';
@@ -93,5 +96,27 @@ describe('windows: screen recording', () => {
             const result = await driver.executeScript('windows: stopRecordingScreen', [{}]) as string;
             expect(result.length).toBeGreaterThan(100);
         });
+
+        it('rejects outputPath with a non-mp4 extension with an explanatory error', async () => {
+            const outputPath = join(tmpdir(), `novawindows-test-recording-${Date.now()}.avi`);
+            await expect(
+                driver.executeScript('windows: startRecordingScreen', [{ outputPath }])
+            ).rejects.toThrow(/\.mp4/);
+        });
+
+        it('recording is saved to the specified outputPath', async () => {
+            const outputPath = join(tmpdir(), `novawindows-test-recording-${Date.now()}.mp4`);
+            try {
+                await driver.executeScript('windows: startRecordingScreen', [{ outputPath }]);
+                await resetCalculator(driver);
+                await driver.executeScript('windows: stopRecordingScreen', [{}]);
+
+                expect(existsSync(outputPath)).toBe(true);
+            } finally {
+                if (existsSync(outputPath)) {
+                    rmSync(outputPath);
+                }
+            }
+        });
     });
 });