Enhance pytest discovery error messages to offer installation option

Co-authored-by: anthonykim1 <[email protected]>

Author: Copilot

src/client/common/constants.ts

@@ -64,6 +64,7 @@ export namespace Commands {
     export const Start_Native_REPL = 'python.startNativeREPL';
     export const Tests_Configure = 'python.configureTests';
     export const Tests_CopilotSetup = 'python.copilotSetupTests';
+    export const Tests_Install_Pytest = 'python.installPytest';
     export const TriggerEnvironmentSelection = 'python.triggerEnvSelection';
     export const ViewOutput = 'python.viewOutput';
 }

src/client/testing/main.ts

@@ -21,6 +21,7 @@ import { ExtensionContextKey } from '../common/application/contextKeys';
 import { checkForFailedTests, updateTestResultMap } from './testController/common/testItemUtilities';
 import { Testing } from '../common/utils/localize';
 import { traceVerbose } from '../logging';
+import { PytestInstallationHelper } from './configuration/pytestInstallationHelper';
 
 @injectable()
 export class TestingService implements ITestingService {
@@ -156,6 +157,22 @@ export class UnitTestManagementService implements IExtensionActivationService {
         await configurationService.promptToEnableAndConfigureTestFramework(wkspace!);
     }
 
+    private async installPytest(workspaceUriString: string): Promise<void> {
+        try {
+            const workspaceUri = Uri.parse(workspaceUriString);
+            const appShell = this.serviceContainer.get<IApplicationShell>(IApplicationShell);
+            const installationHelper = new PytestInstallationHelper(appShell);
+            
+            const success = await installationHelper.promptToInstallPytest(workspaceUri);
+            if (success) {
+                // Refresh test data after successful installation
+                await this.testController?.refreshTestData(workspaceUri, { forceRefresh: true });
+            }
+        } catch (error) {
+            traceVerbose('Error installing pytest from discovery error:', error);
+        }
+    }
+
     private registerCommands(): void {
         const commandManager = this.serviceContainer.get<ICommandManager>(ICommandManager);
 
@@ -195,6 +212,9 @@ export class UnitTestManagementService implements IExtensionActivationService {
                     },
                 };
             }),
+            commandManager.registerCommand(constants.Commands.Tests_Install_Pytest, async (workspaceUriString: string) => {
+                await this.installPytest(workspaceUriString);
+            }),
         );
     }
 

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

@@ -86,9 +86,19 @@ export class PythonResultResolver implements ITestResultResolver {
                 errorNode = createErrorTestItem(this.testController, options);
                 this.testController.items.add(errorNode);
             }
-            const errorNodeLabel: MarkdownString = new MarkdownString(
-                `[Show output](command:python.viewOutput) to view error logs`,
-            );
+            
+            let errorNodeLabel: MarkdownString;
+            // Check if this is a pytest installation error and provide installation link
+            const options = buildErrorNodeOptions(this.workspaceUri, message, this.testProvider);
+            if (options.isPytestNotInstalled) {
+                errorNodeLabel = new MarkdownString(
+                    `[Install pytest](command:python.installPytest?${encodeURIComponent(JSON.stringify([this.workspaceUri.toString()]))}) | [Show output](command:python.viewOutput) to view error logs`,
+                );
+            } else {
+                errorNodeLabel = new MarkdownString(
+                    `[Show output](command:python.viewOutput) to view error logs`,
+                );
+            }
             errorNodeLabel.isTrusted = true;
             errorNode.error = errorNodeLabel;
         } else {

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

@@ -50,7 +50,7 @@ export function removeItemByIdFromChildren(
     });
 }
 
-export type ErrorTestItemOptions = { id: string; label: string; error: string };
+export type ErrorTestItemOptions = { id: string; label: string; error: string; isPytestNotInstalled?: boolean };
 
 export function createErrorTestItem(testController: TestController, options: ErrorTestItemOptions): TestItem {
     const testItem = testController.createTestItem(options.id, options.label);

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

@@ -202,6 +202,7 @@ export function buildErrorNodeOptions(uri: Uri, message: string, testType: strin
         id: `DiscoveryError:${uri.fsPath}`,
         label: `${labelText} [${path.basename(uri.fsPath)}]`,
         error: errorMessage,
+        isPytestNotInstalled: testType === 'pytest' && isPytestNotInstalledError(message),
     };
 }
 

src/test/testing/testController/common/buildErrorNodeOptions.unit.test.ts

@@ -18,6 +18,7 @@ suite('buildErrorNodeOptions - pytest not installed detection', () => {
         expect(result.error).to.equal(
             'pytest is not installed in the selected Python environment. Please install pytest to enable test discovery and execution.',
         );
+        expect(result.isPytestNotInstalled).to.be.true;
     });
 
     test('Should detect pytest ImportError and provide specific message', () => {
@@ -29,6 +30,7 @@ suite('buildErrorNodeOptions - pytest not installed detection', () => {
         expect(result.error).to.equal(
             'pytest is not installed in the selected Python environment. Please install pytest to enable test discovery and execution.',
         );
+        expect(result.isPytestNotInstalled).to.be.true;
     });
 
     test('Should use generic error for non-pytest-related errors', () => {
@@ -38,6 +40,7 @@ suite('buildErrorNodeOptions - pytest not installed detection', () => {
 
         expect(result.label).to.equal('pytest Discovery Error [workspace]');
         expect(result.error).to.equal('Some other error occurred');
+        expect(result.isPytestNotInstalled).to.be.false;
     });
 
     test('Should use generic error for unittest errors', () => {
@@ -47,5 +50,6 @@ suite('buildErrorNodeOptions - pytest not installed detection', () => {
 
         expect(result.label).to.equal('Unittest Discovery Error [workspace]');
         expect(result.error).to.equal("ModuleNotFoundError: No module named 'pytest'");
+        expect(result.isPytestNotInstalled).to.be.undefined;
     });
 });