test: Add unit test for projects/app/src/pages/api/core/dataset/collection/paths.ts (#4350)

* Add unit tests for getDatasetCollectionPaths function and modify paths.ts to export handler.

* Update paths.ts

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Co-authored-by: gru-agent[bot] <185149714+gru-agent[bot]@users.noreply.github.com>
Co-authored-by: Archer <545436317@qq.com>

projects/app/src/pages/api/core/dataset/collection/paths.ts

@@ -5,7 +5,7 @@ import { ParentTreePathItemType } from '@fastgpt/global/common/parentFolder/type
 import { MongoDatasetCollection } from '@fastgpt/service/core/dataset/collection/schema';
 import { NextAPI } from '@/service/middleware/entry';
 
-async function handler(req: NextApiRequest) {
+export async function handler(req: NextApiRequest) {
   const { parentId } = req.query as { parentId: string };
 
   if (!parentId) {

test/cases/pages/api/core/dataset/collection/paths.test.ts

+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { getDatasetCollectionPaths } from '@/pages/api/core/dataset/collection/paths';
+import { MongoDatasetCollection } from '@fastgpt/service/core/dataset/collection/schema';
+
+vi.mock('@fastgpt/service/core/dataset/collection/schema', () => ({
+  MongoDatasetCollection: {
+    findOne: vi.fn()
+  },
+  DatasetColCollectionName: 'dataset_collections'
+}));
+
+describe('getDatasetCollectionPaths', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it('should return empty array for empty parentId', async () => {
+    const result = await getDatasetCollectionPaths({});
+    expect(result).toEqual([]);
+  });
+
+  it('should return empty array if collection not found', async () => {
+    vi.mocked(MongoDatasetCollection.findOne).mockResolvedValueOnce(null);
+
+    const result = await getDatasetCollectionPaths({ parentId: 'nonexistent-id' });
+    expect(result).toEqual([]);
+  });
+
+  it('should return single path for collection without parent', async () => {
+    vi.mocked(MongoDatasetCollection.findOne).mockResolvedValueOnce({
+      _id: 'col1',
+      name: 'Collection 1',
+      parentId: ''
+    });
+
+    const result = await getDatasetCollectionPaths({ parentId: 'col1' });
+    expect(result).toEqual([{ parentId: 'col1', parentName: 'Collection 1' }]);
+  });
+
+  it('should return full path for nested collections', async () => {
+    vi.mocked(MongoDatasetCollection.findOne)
+      .mockResolvedValueOnce({
+        _id: 'col3',
+        name: 'Collection 3',
+        parentId: 'col2'
+      })
+      .mockResolvedValueOnce({
+        _id: 'col2',
+        name: 'Collection 2',
+        parentId: 'col1'
+      })
+      .mockResolvedValueOnce({
+        _id: 'col1',
+        name: 'Collection 1',
+        parentId: ''
+      });
+
+    const result = await getDatasetCollectionPaths({ parentId: 'col3' });
+
+    expect(result).toEqual([
+      { parentId: 'col1', parentName: 'Collection 1' },
+      { parentId: 'col2', parentName: 'Collection 2' },
+      { parentId: 'col3', parentName: 'Collection 3' }
+    ]);
+  });
+
+  it('should handle circular references gracefully', async () => {
+    vi.mocked(MongoDatasetCollection.findOne)
+      .mockResolvedValueOnce({
+        _id: 'col1',
+        name: 'Collection 1',
+        parentId: 'col2'
+      })
+      .mockResolvedValueOnce({
+        _id: 'col2',
+        name: 'Collection 2',
+        parentId: 'col1'
+      });
+
+    const result = await getDatasetCollectionPaths({ parentId: 'col1' });
+
+    expect(result).toEqual([
+      { parentId: 'col2', parentName: 'Collection 2' },
+      { parentId: 'col1', parentName: 'Collection 1' }
+    ]);
+  });
+});