diff --git a/src/vs/workbench/api/node/extHostSearch.ts b/src/vs/workbench/api/node/extHostSearch.ts
index aeba2749c5f..4f9c48ed0eb 100644
--- a/src/vs/workbench/api/node/extHostSearch.ts
+++ b/src/vs/workbench/api/node/extHostSearch.ts
@@ -621,7 +621,10 @@ class FileSearchEngine {
 				.then(() => {
 					this.activeCancellationTokens.add(cancellation);
 					return this.provider.provideFileSearchResults(
-						{ cacheKey: this.config.cacheKey, pattern: this.config.filePattern || '' },
+						{
+							pattern: this.config.filePattern || '',
+							cacheKey: this.config.cacheKey + '_' + fq.folder.fsPath
+						},
 						options,
 						{ report: onProviderResult },
 						cancellation.token);
diff --git a/src/vs/workbench/test/electron-browser/api/extHostSearch.test.ts b/src/vs/workbench/test/electron-browser/api/extHostSearch.test.ts
index 3c5cceb4ce7..49d33da63b2 100644
--- a/src/vs/workbench/test/electron-browser/api/extHostSearch.test.ts
+++ b/src/vs/workbench/test/electron-browser/api/extHostSearch.test.ts
@@ -666,27 +666,33 @@ suite('ExtHostSearch', () => {
 			compareURIs(results, reportedResults);
 		});
 
-		// Mock fs?
-		// test('Returns result for absolute path', async () => {
-		// 	const queriedFile = makeFileResult(rootFolderA, 'file2.ts');
-		// 	const reportedResults = [
-		// 		makeFileResult(rootFolderA, 'file1.ts'),
-		// 		queriedFile,
-		// 		makeFileResult(rootFolderA, 'file3.ts'),
-		// 	];
+		test('uses different cache keys for different folders', async () => {
+			const cacheKeys: string[] = [];
+			await registerTestSearchProvider({
+				provideFileSearchResults(query: vscode.FileSearchQuery, options: vscode.FileSearchOptions, progress: vscode.Progress<URI>, token: vscode.CancellationToken): Thenable<void> {
+					cacheKeys.push(query.cacheKey);
+					return TPromise.wrap(null);
+				}
+			});
 
-		// 	await registerTestSearchProvider({
-		// 		provideFileSearchResults(options: vscode.FileSearchOptions, progress: vscode.Progress<URI>, token: vscode.CancellationToken): Thenable<void> {
-		// 			reportedResults.forEach(r => progress.report(r));
-		// 			return TPromise.wrap(null);
-		// 		}
-		// 	});
+			const query: ISearchQuery = {
+				type: QueryType.File,
+				filePattern: '',
+				cacheKey: 'cacheKey',
+				folderQueries: [
+					{
+						folder: rootFolderA
+					},
+					{
+						folder: rootFolderB
+					}
+				]
+			};
 
-		// 	const queriedFilePath = queriedFile.fsPath;
-		// 	const { results } = await runFileSearch(getSimpleQuery(queriedFilePath));
-		// 	assert.equal(results.length, 1);
-		// 	compareURIs(results, [queriedFile]);
-		// });
+			await runFileSearch(query);
+			assert.equal(cacheKeys.length, 2);
+			assert.notEqual(cacheKeys[0], cacheKeys[1]);
+		});
 	});
 
 	suite('Text:', () => {