Workspace & resolver tests (microsoft#21441)

This PR
- moves populateTestTree to utils
- adds tests for execution adapters (pytest and unittest)
- resultResolver tests
- workspaceTestAdapater tests

src/client/testing/testController/common/utils.ts

@@ -188,3 +188,69 @@ export function populateTestTree(
 function isTestItem(test: DiscoveredTestNode | DiscoveredTestItem): test is DiscoveredTestItem {
     return test.type_ === 'test';
 }
+
+export function buildErrorNodeOptions(uri: Uri, message: string, testType: string): ErrorTestItemOptions {
+    const labelText = testType === 'pytest' ? 'Pytest Discovery Error' : 'Unittest Discovery Error';
+    return {
+        id: `DiscoveryError:${uri.fsPath}`,
+        label: `${labelText} [${path.basename(uri.fsPath)}]`,
+        error: message,
+    };
+}
+
+export function populateTestTree(
+    testController: TestController,
+    testTreeData: DiscoveredTestNode,
+    testRoot: TestItem | undefined,
+    resultResolver: ITestResultResolver,
+    token?: CancellationToken,
+): void {
+    // If testRoot is undefined, use the info of the root item of testTreeData to create a test item, and append it to the test controller.
+    if (!testRoot) {
+        testRoot = testController.createTestItem(testTreeData.path, testTreeData.name, Uri.file(testTreeData.path));
+
+        testRoot.canResolveChildren = true;
+        testRoot.tags = [RunTestTag, DebugTestTag];
+
+        testController.items.add(testRoot);
+    }
+
+    // Recursively populate the tree with test data.
+    testTreeData.children.forEach((child) => {
+        if (!token?.isCancellationRequested) {
+            if (isTestItem(child)) {
+                const testItem = testController.createTestItem(child.id_, child.name, Uri.file(child.path));
+                testItem.tags = [RunTestTag, DebugTestTag];
+
+                const range = new Range(
+                    new Position(Number(child.lineno) - 1, 0),
+                    new Position(Number(child.lineno), 0),
+                );
+                testItem.canResolveChildren = false;
+                testItem.range = range;
+                testItem.tags = [RunTestTag, DebugTestTag];
+
+                testRoot!.children.add(testItem);
+                // add to our map
+                resultResolver.runIdToTestItem.set(child.runID, testItem);
+                resultResolver.runIdToVSid.set(child.runID, child.id_);
+                resultResolver.vsIdToRunId.set(child.id_, child.runID);
+            } else {
+                let node = testController.items.get(child.path);
+
+                if (!node) {
+                    node = testController.createTestItem(child.id_, child.name, Uri.file(child.path));
+
+                    node.canResolveChildren = true;
+                    node.tags = [RunTestTag, DebugTestTag];
+                    testRoot!.children.add(node);
+                }
+                populateTestTree(testController, child, node, resultResolver, token);
+            }
+        }
+    });
+}
+
+function isTestItem(test: DiscoveredTestNode | DiscoveredTestItem): test is DiscoveredTestItem {
+    return test.type_ === 'test';
+}