feat: Add audio and video support to read_file

This commit enhances the `read_file` tool to support audio and video files.

It updates the `detectFileType` function to recognize audio and video MIME types,
and modifies the `processSingleFileContent` function to handle these new file types.
This change allows the `read_file` tool to process a wider range of file formats,
 improving its multimodal capabilities.

It adds the tests in `fileUtil.test.ts` regarding the changes and it adds a targeted mock in
`read-many-files.test.ts` file to work around a dependency's bug, and tests the actual feature
in its own dedicated unit test file.

fixes #1556

Author: santhoshkumarCodes

packages/core/src/tools/read-many-files.test.ts

@@ -6,6 +6,27 @@
 
 import { vi } from 'vitest';
 import type { Mock } from 'vitest';
+
+vi.mock('mime-types', () => {
+  const lookup = (filename: string) => {
+    if (filename.endsWith('.ts') || filename.endsWith('.js')) {
+      return 'text/plain';
+    }
+    if (filename.endsWith('.png')) {
+      return 'image/png';
+    }
+    if (filename.endsWith('.pdf')) {
+      return 'application/pdf';
+    }
+    return false;
+  };
+  return {
+    default: {
+      lookup,
+    },
+    lookup,
+  };
+});
 import { describe, it, expect, beforeEach, afterEach } from 'vitest';
 import { mockControl } from '../__mocks__/fs/promises.js';
 import { ReadManyFilesTool } from './read-many-files.js';

packages/core/src/utils/fileUtils.test.ts

@@ -211,6 +211,16 @@ describe('fileUtils', () => {
       expect(detectFileType('file.pdf')).toBe('pdf');
     });
 
+    it('should detect audio type by extension', () => {
+      mockMimeLookup.mockReturnValueOnce('audio/mpeg');
+      expect(detectFileType('song.mp3')).toBe('audio');
+    });
+
+    it('should detect video type by extension', () => {
+      mockMimeLookup.mockReturnValueOnce('video/mp4');
+      expect(detectFileType('movie.mp4')).toBe('video');
+    });
+
     it('should detect known binary extensions as binary (e.g. .zip)', () => {
       mockMimeLookup.mockReturnValueOnce('application/zip');
       expect(detectFileType('archive.zip')).toBe('binary');

packages/core/src/utils/fileUtils.ts

@@ -94,19 +94,27 @@ export function isBinaryFile(filePath: string): boolean {
 /**
  * Detects the type of file based on extension and content.
  * @param filePath Path to the file.
- * @returns 'text', 'image', 'pdf', or 'binary'.
+ * @returns 'text', 'image', 'pdf', 'audio', 'video', or 'binary'.
  */
 export function detectFileType(
   filePath: string,
-): 'text' | 'image' | 'pdf' | 'binary' {
+): 'text' | 'image' | 'pdf' | 'audio' | 'video' | 'binary' {
   const ext = path.extname(filePath).toLowerCase();
   const lookedUpMimeType = mime.lookup(filePath); // Returns false if not found, or the mime type string
 
-  if (lookedUpMimeType && lookedUpMimeType.startsWith('image/')) {
-    return 'image';
-  }
-  if (lookedUpMimeType && lookedUpMimeType === 'application/pdf') {
-    return 'pdf';
+  if (lookedUpMimeType) {
+    if (lookedUpMimeType.startsWith('image/')) {
+      return 'image';
+    }
+    if (lookedUpMimeType.startsWith('audio/')) {
+      return 'audio';
+    }
+    if (lookedUpMimeType.startsWith('video/')) {
+      return 'video';
+    }
+    if (lookedUpMimeType === 'application/pdf') {
+      return 'pdf';
+    }
   }
 
   // Stricter binary check for common non-text extensions before content check
@@ -253,7 +261,9 @@ export async function processSingleFileContent(
         };
       }
       case 'image':
-      case 'pdf': {
+      case 'pdf':
+      case 'audio':
+      case 'video': {
         const contentBuffer = await fs.promises.readFile(filePath);
         const base64Data = contentBuffer.toString('base64');
         return {