diff --git a/test-provider-sample/.gitignore b/test-provider-sample/.gitignore
index a4c10718..a6fcc128 100644
--- a/test-provider-sample/.gitignore
+++ b/test-provider-sample/.gitignore
@@ -4,4 +4,4 @@ node_modules
 *.vsix
 
 /vscode.d.ts
-/vscode.proposed.testCoverage.d.ts
+/vscode.proposed.*.d.ts
diff --git a/test-provider-sample/package-lock.json b/test-provider-sample/package-lock.json
index 6d007d0e..a31ce300 100644
--- a/test-provider-sample/package-lock.json
+++ b/test-provider-sample/package-lock.json
@@ -1277,9 +1277,9 @@
 			"dev": true
 		},
 		"vscode-dts": {
-			"version": "0.3.2",
-			"resolved": "https://registry.npmjs.org/vscode-dts/-/vscode-dts-0.3.2.tgz",
-			"integrity": "sha512-vL6p3MYuRgyvztEyK/X+7KH8JqMrqzxSvZZi8e0eMubCj2v0POmypitJ93EcHSkZbULA2mCK6mdp5bZ5Re/bZw==",
+			"version": "0.3.3",
+			"resolved": "https://registry.npmjs.org/vscode-dts/-/vscode-dts-0.3.3.tgz",
+			"integrity": "sha512-JfOsWL0NvfVw0UF9bcTjlv1Onz3Ted7cgpPWKWMnHGB+72t/tn8WFDeKLZO42l2k9KJq/NGS9rFC5gZbyI4FTg==",
 			"dev": true,
 			"requires": {
 				"minimist": "^1.2.0",
diff --git a/test-provider-sample/package.json b/test-provider-sample/package.json
index 614694df..0dc25f53 100644
--- a/test-provider-sample/package.json
+++ b/test-provider-sample/package.json
@@ -5,9 +5,9 @@
 	"version": "0.0.1",
 	"publisher": "vscode-samples",
 	"repository": "https://github.com/Microsoft/vscode-extension-samples",
-	"enableProposedApi": true,
 	"enabledApiProposals": [
-		"testCoverage"
+		"testCoverage",
+		"testRefresh"
 	],
 	"engines": {
 		"vscode": "^1.51.0"
@@ -39,6 +39,6 @@
 		"@typescript-eslint/parser": "^4.16.0",
 		"eslint": "^7.21.0",
 		"typescript": "^4.2.2",
-		"vscode-dts": "^0.3.2"
+		"vscode-dts": "^0.3.3"
 	}
 }
diff --git a/test-provider-sample/src/extension.ts b/test-provider-sample/src/extension.ts
index ea89f4d9..08222225 100644
--- a/test-provider-sample/src/extension.ts
+++ b/test-provider-sample/src/extension.ts
@@ -85,7 +85,11 @@ export async function activate(context: vscode.ExtensionContext) {
 
     discoverTests(request.include ?? gatherTestItems(ctrl.items)).then(runTestQueue);
   };
-  
+
+  ctrl.refreshHandler = async () => {
+    await Promise.all(getWorkspaceTestPatterns().map(({ pattern }) => findInitialFiles(ctrl, pattern)));
+  };
+
   ctrl.createRunProfile('Run Tests', vscode.TestRunProfileKind.Run, runHandler, true);
 
   ctrl.resolveHandler = async item => {
@@ -145,13 +149,25 @@ function gatherTestItems(collection: vscode.TestItemCollection) {
   return items;
 }
 
-function startWatchingWorkspace(controller: vscode.TestController) {
+function getWorkspaceTestPatterns() {
   if (!vscode.workspace.workspaceFolders) {
     return [];
   }
 
-  return vscode.workspace.workspaceFolders.map(workspaceFolder => {
-    const pattern = new vscode.RelativePattern(workspaceFolder, '**/*.md');
+  return vscode.workspace.workspaceFolders.map(workspaceFolder => ({
+    workspaceFolder,
+    pattern: new vscode.RelativePattern(workspaceFolder, '**/*.md'),
+  }));
+}
+
+async function findInitialFiles(controller: vscode.TestController, pattern: vscode.GlobPattern) {
+  for (const file of await vscode.workspace.findFiles(pattern)) {
+    getOrCreateFile(controller, file);
+  }
+}
+
+function startWatchingWorkspace(controller: vscode.TestController) {
+  return getWorkspaceTestPatterns().map(({ workspaceFolder, pattern }) => {
     const watcher = vscode.workspace.createFileSystemWatcher(pattern);
 
     watcher.onDidCreate(uri => getOrCreateFile(controller, uri));
@@ -163,11 +179,7 @@ function startWatchingWorkspace(controller: vscode.TestController) {
     });
     watcher.onDidDelete(uri => controller.items.delete(uri.toString()));
 
-    vscode.workspace.findFiles(pattern).then(files => {
-      for (const file of files) {
-        getOrCreateFile(controller, file);
-      }
-    });
+    findInitialFiles(controller, pattern);
 
     return watcher;
   });
diff --git a/test-provider-sample/src/testTree.ts b/test-provider-sample/src/testTree.ts
index 24140232..0c816d8e 100644
--- a/test-provider-sample/src/testTree.ts
+++ b/test-provider-sample/src/testTree.ts
@@ -29,7 +29,7 @@ export class TestFile {
       item.error = undefined;
       this.updateFromContents(controller, content, item);
     } catch (e) {
-      item.error = e.stack;
+      item.error = (e as Error).stack;
     }
   }