Merge pull request Expensify#86632 from twilight2294/issue/85928

Fix: Share sheet flow is busted

Author: NikkiWines

src/libs/fileDownload/checkFileExists/index.ts

@@ -21,6 +21,12 @@ function checkFileExists(path: string | undefined): Promise<boolean> {
         decodedPath = path;
     }
 
+    // RNFS.stat uses NSFileManager.attributesOfItemAtPath: which expects
+    // a POSIX path, not a file:// URI
+    if (decodedPath.startsWith('file://')) {
+        decodedPath = decodedPath.slice(7);
+    }
+
     // RNFS.stat() returns file info without loading the file content
     return RNFS.stat(decodedPath)
         .then((fileStat) => {

tests/unit/checkFileExistsTest.ts

@@ -0,0 +1,59 @@
+import type RNFS from 'react-native-fs';
+import checkFileExists from '@libs/fileDownload/checkFileExists/index';
+
+const mockStat = jest.fn<Promise<RNFS.StatResult>, [string]>();
+
+jest.mock('react-native-fs', () => ({
+    stat: (...args: [string]) => mockStat(...args),
+}));
+
+describe('checkFileExists', () => {
+    beforeEach(() => {
+        mockStat.mockReset();
+    });
+
+    it('should return false for undefined path', async () => {
+        const result = await checkFileExists(undefined);
+        expect(result).toBe(false);
+        expect(mockStat).not.toHaveBeenCalled();
+    });
+
+    it('should return false for empty string', async () => {
+        const result = await checkFileExists('');
+        expect(result).toBe(false);
+        expect(mockStat).not.toHaveBeenCalled();
+    });
+
+    it('should call RNFS.stat with a plain POSIX path', async () => {
+        mockStat.mockResolvedValue({isFile: () => true} as RNFS.StatResult);
+        const result = await checkFileExists('/var/mobile/Containers/shared_image.png');
+        expect(result).toBe(true);
+        expect(mockStat).toHaveBeenCalledWith('/var/mobile/Containers/shared_image.png');
+    });
+
+    it('should strip file:// prefix before calling RNFS.stat', async () => {
+        mockStat.mockResolvedValue({isFile: () => true} as RNFS.StatResult);
+        const result = await checkFileExists('file:///var/mobile/Containers/shared_image.png');
+        expect(result).toBe(true);
+        expect(mockStat).toHaveBeenCalledWith('/var/mobile/Containers/shared_image.png');
+    });
+
+    it('should decode URI-encoded paths', async () => {
+        mockStat.mockResolvedValue({isFile: () => true} as RNFS.StatResult);
+        const result = await checkFileExists('file:///var/mobile/Containers/my%20receipt.png');
+        expect(result).toBe(true);
+        expect(mockStat).toHaveBeenCalledWith('/var/mobile/Containers/my receipt.png');
+    });
+
+    it('should return false when RNFS.stat throws', async () => {
+        mockStat.mockRejectedValue(new Error('File not found'));
+        const result = await checkFileExists('/nonexistent/path');
+        expect(result).toBe(false);
+    });
+
+    it('should return false when path is a directory', async () => {
+        mockStat.mockResolvedValue({isFile: () => false} as RNFS.StatResult);
+        const result = await checkFileExists('/var/mobile/Containers/');
+        expect(result).toBe(false);
+    });
+});