diff --git a/src/vs/workbench/api/common/extHostTesting.ts b/src/vs/workbench/api/common/extHostTesting.ts
index ac0487a7540..da3c546066d 100644
--- a/src/vs/workbench/api/common/extHostTesting.ts
+++ b/src/vs/workbench/api/common/extHostTesting.ts
@@ -267,11 +267,8 @@ export class ExtHostTesting implements ExtHostTestingShape {
 						}
 					}
 
-					const internal = this.getInternalTestForReference(test);
-					if (internal) {
-						this.flushCollectionDiffs();
-						this.proxy.$updateTestStateInRun(req.runId, internal.item.extId, TestState.from(state));
-					}
+					this.flushCollectionDiffs();
+					this.proxy.$updateTestStateInRun(req.runId, test.id, TestState.from(state));
 				},
 				tests: includeTests.map(t => TestItemFilteredWrapper.unwrap(t.actual)),
 				exclude: excludeTests.map(([, t]) => TestItemFilteredWrapper.unwrap(t.actual)),
@@ -331,6 +328,14 @@ export class ExtHostTesting implements ExtHostTestingShape {
 			return;
 		}
 
+		const onDidInvalidateTest = new Emitter<vscode.TestItem>();
+		workspaceHierarchy.onDidInvalidateTest?.(node => {
+			const wrapper = TestItemFilteredWrapper.getWrapperForTestItem(node, document);
+			if (wrapper.hasNodeMatchingFilter) {
+				onDidInvalidateTest.fire(wrapper);
+			}
+		});
+
 		const onDidChangeTest = new Emitter<vscode.TestItem>();
 		workspaceHierarchy.onDidChangeTest(node => {
 			const wrapper = TestItemFilteredWrapper.getWrapperForTestItem(node, document);
@@ -373,6 +378,8 @@ export class ExtHostTesting implements ExtHostTestingShape {
 				onDidChangeTest.dispose();
 				TestItemFilteredWrapper.removeFilter(document);
 			},
+			discoveredInitialTests: workspaceHierarchy.discoveredInitialTests,
+			onDidInvalidateTest: onDidInvalidateTest.event,
 			onDidChangeTest: onDidChangeTest.event
 		};
 	}
diff --git a/src/vs/workbench/contrib/testing/common/ownedTestCollection.ts b/src/vs/workbench/contrib/testing/common/ownedTestCollection.ts
index e9895e00094..64065246000 100644
--- a/src/vs/workbench/contrib/testing/common/ownedTestCollection.ts
+++ b/src/vs/workbench/contrib/testing/common/ownedTestCollection.ts
@@ -271,6 +271,13 @@ export class SingleUseTestCollection implements IDisposable {
 			const deletedChildren = internal.previousChildren;
 			const currentChildren = new Set<string>();
 			for (const child of actual.children) {
+				// If a child was recreated, delete the old object before calling
+				// addItem() anew.
+				const previous = this.testIdToInternal.object.get(child.id);
+				if (previous && previous.actual !== child) {
+					this.removeItembyId(child.id);
+				}
+
 				const c = this.addItem(child, providerId, internal.item.extId);
 				deletedChildren.delete(c.item.extId);
 				currentChildren.add(c.item.extId);