Add Copilot to Testing docs (#7931)

* Update Testing intro and about

* Add write tests with AI section

* Add AI-assisted test writing and fixing

* Edit pass

docs/editor/testing.md

@@ -9,115 +9,169 @@ MetaDescription: One of the great things in Visual Studio Code is testing suppor
 ---
 # Testing
 
-Software testing is a crucial aspect of the software development process. It helps ensure that your code works as expected and catches bugs early in the development cycle. Visual Studio Code provides a rich set of features for testing your code. You can automatically discover tests in your project, run and debug your tests, and get test coverage results.
+Visual Studio Code provides a rich set of features for testing your code. You can automatically discover tests in your project, run and debug your tests, and get test coverage results. GitHub Copilot in VS Code can assist with setting up the testing framework for your project, and help you generate test code and fix failing tests.
 
-In this article, you'll learn how to get started with testing in VS Code, discover popular testing extensions, and explore the testing capabilities.
+In this article, you'll learn how to start with testing in VS Code, find popular testing extensions, and explore the testing features. You'll also learn how Copilot in VS Code can help you write tests faster and can assist you in fixing failing tests.
 
-![Testing in Visual Studio Code](images/testing/testing-hero.png)
+> [!TIP]
+> If you don't have a Copilot subscription yet, use Copilot for free by signing up for the [Copilot Free plan](https://github.com/github-copilot/signup). You'll get a monthly limit of completions and chat interactions.
 
-## Getting started with testing in VS Code
+<!-- ![Testing in Visual Studio Code](images/testing/testing-hero.png) -->
 
-Testing support in VS Code is language-specific and depends on the [extensions](#testing-extensions) you have installed. Language extensions or standalone extension can implement the testing features for a particular language or testing framework. To get started with testing in VS Code, first install the appropriate extension for your project.
+## About testing in VS Code
 
-After you have installed the extension, you can start discovering and running tests in your project. The [Test Explorer](#automatic-test-discovery-in-test-explorer) provides a centralized place to manage and run your tests.
+Testing support in VS Code is language-specific and depends on the [testing extensions](#extensions-for-testing) you have installed. Language extensions or standalone extensions can implement the testing features for a particular language or testing framework.
 
-After you run your tests, you can view the test results in the Test Explorer view, editor gutter, and Test Results panel. To diagnose issues with your tests, you can also [run and debug tests](#run-and-debug-tests) and set breakpoints in your test and application code.
+VS Code has the following features for testing your code:
 
-You can also [run tests with coverage](#test-coverage) to see how much of your code is covered by your tests. Test coverage helps you identify areas of your code that are not being tested and ensures that your tests are comprehensive. You can view the test coverage results in different views in the editor and Test Coverage panel.
+* **Support multiple testing frameworks**: language [extensions](#extensions-for-testing) and standalone testing extensions provide support for various languages and test runners, such as Jest, Mocha, Pytest, JUnit, and more.
 
-To optimize your testing workflow, you can [create tasks to run your tests](#task-integration), and optionally run your tests in the background with every code change.
+* **Centralized test management**: the [Test Explorer](#automatic-test-discovery-in-test-explorer) provides a centralized place to manage and run the tests in your project. The Test Explorer might automatically discover the tests in your project, depending on the testing extension.
 
-## Testing extensions
+* **Integrated test results**: view the test status inline in the editor alongside the test code, or view all tests in the Test Explorer. Detailed test results are available in the Test Results panel.
+
+* **Debugging**: [debug](#run-and-debug-tests) your tests to diagnose test failures. Take advantage of the rich [debugging support](/docs/editor/debugging.md) in VS Code, such as breakpoints, watch variables, and more.
+
+* **Test coverage**: [run tests with coverage](#test-coverage) to see how much of your code is covered by your tests.
+
+* **AI-assisted testing**: use GitHub Copilot in VS Code to assist you with setting up your testing framework, generating test code, and fixing failing tests.
+
+* **Task integration**: make your testing work easier by [creating tasks to run your tests](#task-integration). You can also run your tests in the background when you change your code.
+
+## Get started with testing in VS Code
+
+To get started with testing in VS Code, follow these steps:
+
+1. Open the Extensions view and install a testing extension for your project. Filter the extensions by the **Testing** category (_@category:"testing"_).
+
+1. Select the beaker icon (<i class="codicon codicon-beaker"></i>) in the Activity Bar to open the Test Explorer and discover the tests in your project.
+
+1. Run and debug your tests from the Test Explorer or directly from the editor.
+
+## Extensions for testing
 
 You can find extensions that support testing by looking in the [Visual Studio Marketplace](https://marketplace.visualstudio.com/search?target=VSCode&category=Testing&sortBy=Installs). You can also go to the Extensions view (`kb(workbench.view.extensions)`), and filter by the **Testing** category.
 
 <div class="marketplace-extensions-testing-tools-curated"></div>
 
-> **Tip**: The extensions shown above are dynamically queried. Select an extension tile to read the description and reviews to decide which extension is best for you.
+> [!TIP]
+> Copilot can assist with setting up a testing framework and suggesting relevant testing extensions. Open the Chat view (`kb(workbench.action.chat.open)`), enter the `/setupTests` command, and Copilot will guide you through the process of configuring your project.
 
-## Automatic test discovery in Test Explorer
+## Automatic test discovery in Testing view
 
-The Test Explorer view provides a centralized place to manage and run your tests. You can access the Test Explorer view by selecting the beaker icon in the Activity Bar or by using the **Testing: Focus on Test Explorer View** command in the Command Palette (`kb(workbench.action.showCommands)`).
+The Testing view provides a centralized place to manage and run your tests. You can get to the Testing view by selecting the beaker icon (<i class="codicon codicon-beaker"></i>) in the Activity Bar. You can also use the **Testing: Focus on Test Explorer View** command in the Command Palette (`kb(workbench.action.showCommands)`).
 
 If you have a project with tests, the Test Explorer view discovers and lists the tests in your workspace. By default, the discovered tests are displayed in a tree view in the Test Explorer. The tree view matches the hierarchical structure of your tests, making it easy to navigate and run your tests.
 
-![Test Explorer view](images/testing/test-explorer-view.png)
+![Screenshot that shows VS Code with the Test Explorer showing the tests, matching the test code that is shown in the editor.](images/testing/test-explorer-view.png)
 
 You can run tests from the Test Explorer by selecting the play button. Learn more about running and debugging tests in the [Run and debug tests](#run-and-debug-tests) section.
 
-The tree view shows the test result status for each test by using a visual indicator, and enables you to run and debug tests, and navigate to the test code.
-
-![Test Explorer view with test results](images/testing/test-explorer-view-test-results.png)
-
-> **Tip**: You can navigate to the test code by double-clicking on the test in the Test Explorer view. If you select a test that failed, the editor opens the test file, highlights the failed test, and shows the error message.
+> [!TIP]
+> Navigate to the test code by double-clicking on the test in the Test Explorer view. If you select a test that failed, the editor opens the test file, highlights the failed test, and shows the error message.
 
 If you have many tests, you can use the filtering options to quickly find the tests you're interested in. You can use the **Filter** button to filter tests by status or only show tests for the current file. You can also use the search box to search for specific tests by name or use the `@` symbol to search by status.
 
 ![Test Explorer view with filtering options](images/testing/test-explorer-view-filtering.png)
 
-In the **More Actions** menu, you can access additional functionality, such as sort and display options.
+In the **More Actions** menu, you can access more functionality, such as sort and display options.
 
-If you add new tests or make changes to your tests, use the **Refresh Tests** button to refresh the list of tests in the Test Explorer. You can also use the **Test Explorer: Reload tests** command in the Command Palette (`kb(workbench.action.showCommands)`).
+If you add new tests or change your tests, use the **Refresh Tests** button to refresh the list of tests in the Test Explorer. You can also use the **Test Explorer: Reload tests** command in the Command Palette (`kb(workbench.action.showCommands)`).
 
-> **Note**: Depending on the testing extension, you might first have to configure the test framework or test runner to discover the tests in your project. Consult the documentation of the testing extension for more information.
+> [!NOTE]
+> Depending on the testing extension, you might first have to configure the test framework or test runner to discover the tests in your project. For more information, consult the documentation of the testing extension. You can use the `setupTests` command in Copilot Chat view to get help with setting up a testing framework for your project.
 
-## Run and debug tests
+## Write tests with AI
+
+Writing tests can be time-consuming and they're often neglected. Copilot can speed up the process of writing tests by creating test code for your application. You can use it to write unit tests, integration tests, end-to-end tests, and more.
+
+To write tests with Copilot in VS Code, you can use either of these methods:
+
+* Editor smart actions
 
-After the discovery of the tests in your project, you can run and debug your tests, and view test results directly from within VS Code. You have multiple options to run and debug tests:
+	1. Optionally, select a block of application code
 
-- Use the actions in the Test Explorer view to run all or a subset of tests
-- Use the controls in the editor gutter to run tests while you're editing your test code
-- Use the commands to run tests from the Command Palette (`kb(workbench.action.showCommands)`)
+	1. Right-click in the editor, and then select **Copilot** > **Generate Tests**
 
-In the Test Explorer, use the controls in the section heading to run or debug all tests. You can also run or debug individual tests by selecting the play or debug icon next to the test name. In the tree view, when you select to run or debug on a specific node, all tests under that node are run or debugged.
+* Chat prompts
+
+	1. Open the application code file for which you want to generate tests
+
+	1. Open the Copilot Edits (`kb(workbench.action.chat.openEditSession)`), the Chat view (`kb(workbench.action.chat.open)`), or the editor Inline Chat (`kb(inlineChat.start)`)
+
+	1. Enter a prompt to generate tests, such as _Generate tests for this code. Also include tests for edge cases._
+
+		Add extra context to your prompt by typing `#file` in the prompt. For example, _Generate tests for this code #file:calculator.js_
+
+		> [!TIP]
+		> Get more example prompts for [generating unit tests](https://docs.github.com/en/copilot/example-prompts-for-github-copilot-chat/testing-code/generate-unit-tests), [mock objects](https://docs.github.com/en/copilot/example-prompts-for-github-copilot-chat/testing-code/create-mock-objects-to-abstract-layers), or [end-to-end tests](https://docs.github.com/en/copilot/example-prompts-for-github-copilot-chat/testing-code/create-end-to-end-tests-for-a-webpage) in the GitHub Copilot documentation.
+
+Copilot will generate test cases code for your application code. If you already have a tests file, Copilot will add the tests there, or create a new file, if needed. You can further customize the generated tests by providing more prompts to Copilot. For example, you can ask Copilot to use another testing framework.
+
+> [!TIP]
+> You can give Copilot your own [special instructions for generating code](/docs/copilot/copilot-customization.md). For example, you can tell Copilot to use a certain testing framework, naming convention, or code structure.
+
+Learn more about [using Copilot in VS Code](/docs/copilot/overview.md).
+
+## Run and debug tests
+
+After the discovery of the tests in your project, you can run and debug your tests, and view test results directly from within VS Code.
+
+In the Test Explorer, use the controls in the section heading to run or debug all tests. You can also run or debug specific tests in the tree view by selecting the run/debug icon on a specific node.
 
 ![Run and debug tests in Test Explorer](images/testing/run-debug-tests-test-explorer.png)
 
-While you're viewing your test code in the editor, you can use the play control in the gutter to run the test at the current cursor position. Right-click on the gutter control to view other actions, such as debugging the test.
+As you're viewing the test code in the editor, use the play control in the editor gutter to run the test at that position.
 
 ![Run and debug tests in editor gutter](images/testing/run-debug-tests-editor-gutter.png)
 
-> **Tip**: you can configure the default testing action for the gutter control by using the `setting(testing.defaultGutterClickAction)` setting.
+Right-click on the gutter control to view other actions, such as debugging the test.
 
-After running a test, the editor gutter displays the test status.
+> [!TIP]
+> Configure the default testing action for the gutter control by using the `setting(testing.defaultGutterClickAction)` setting.
 
-When you run tests, the test result status is displayed in the Test Explorer view and editor gutter. The test results are color-coded to indicate the status of the test (pass or fail). When a test fails, notice that the test error message is shown as an overlay in the editor.
+After you run one or more tests, the editor gutter and tree view in the Test Explorer display the corresponding test status (passed/failed). When a test fails, notice that the test error message is shown as an overlay in the editor.
+
+![Screenshot that shows a test error message overlay in the editor.](images/testing/editor-failed-test-message.png)
 
 Use the **Show Output** button in the Test Explorer to view the test output in the **Test Results** panel.
 
 ![Test Results panel](images/testing/test-results-panel.png)
 
-You can access the commands for the Test Explorer, such as running or debugging tests, via the Command Palette (`kb(workbench.action.showCommands)`). Enter `Test Explorer:` to find the corresponding commands.
+> [!TIP]
+> Copilot can help you fix failing tests. In the Test Explorer, hover over the tree view, and select the **Fix Test Failure** button (_sparkle_) and Copilot will suggest a fix for the failing test. Alternatively, enter the `/fixTestFailure` command in Copilot Chat.
+
+![Screenshot showing the Test Explorer, highlighting the "Fix Test Failure" button, and the editor that shows a suggestion from Copilot on how to fix the failing test.](images/testing/copilot-fix-test-failure.png)
 
 ## Test coverage
 
 Test coverage is a measure of how much of your code is covered by your tests. It helps you identify areas of your code that are not being tested. VS Code supports running tests with coverage and viewing the coverage results if the corresponding testing extension support test coverage.
 
-Similar to running and debugging tests, you can run tests with coverage by using the actions in the Test Explorer view, editor gutter, or commands in the Command Palette (`kb(workbench.action.showCommands)`).
+You can run tests with coverage, just like you can run and debug tests. Use corresponding the actions in the Test Explorer view, editor gutter, or commands in the Command Palette (`kb(workbench.action.showCommands)`).
 
 ![Run tests with coverage](images/testing/run-tests-with-coverage.png)
 
 After you run tests with coverage, you can view the coverage results in different locations:
 
-- In the Test Coverage view
+* In the Test Coverage view
 
     A tree view shows the tests with their coverage percentage. A color indicator also gives a visual cue about the coverage percentage. Hover over each line to see more details about the coverage results.
 
     ![Test Coverage view](images/testing/test-coverage-view.png)
 
-- As an overlay in the editor
+* As an overlay in the editor
 
     For code files that have test coverage, the editor shows a color overlay in the gutter to indicate which lines are covered by tests or not. When you hover over the gutter, notice that for covered lines, there is also an indicator for the number of times the line was executed. You can also select the **Show Inline Coverage** button in the editor title bar or use the **Test: Show Inline Coverage** command (`kb(testing.toggleInlineCoverage)`) to toggle the coverage overlay.
 
     ![View coverage in editor](images/testing/view-coverage-in-editor.png)
 
-- In the Explorer view, which shows the coverage percentage of your code files
+* In the Explorer view, which shows the coverage percentage of your code files
 
     The Explorer view shows the coverage percentage of your code files. Hover over a file or node in the Explorer to see more details about the coverage results.
 
     ![View coverage in Explorer view](images/testing/view-coverage-in-explorer.png)
 
-- In the diff editor
+* In the diff editor
 
     If you have a diff editor open, the coverage results are also shown in the diff editor, similar to how they're shown in the editor.
 
@@ -152,7 +206,8 @@ To run the test task, use the command **Tasks: Run Test Task** or [create a keyb
 
 Learn more about [using and configuring Tasks](/docs/editor/tasks.md).
 
-> **Note**: Currently, tasks don't have special integration into VS Code's testing functionality, so running tests in a task won't update the user interface. Individual testing extensions can provide specific test automation functionality that integrates in the UI.
+> [!NOTE]
+> Currently, tasks don't have special integration into VS Code's testing functionality, so running tests in a task won't update the user interface. Individual testing extensions can provide specific test automation functionality that integrates in the UI.
 
 ## Test configuration settings
 
@@ -171,5 +226,8 @@ You can find all testing-related settings in the Settings editor (`kb(workbench.
 
 ## Next steps
 
-- Get started with testing in [Python](/docs/python/testing.md), [Java](/docs/java/java-testing.md), or [C#](/docs/csharp/testing.md)
-- Learn more about [using and configuring Tasks](/docs/editor/tasks.md)
+* Get started with testing in [Python](/docs/python/testing.md), [Java](/docs/java/java-testing.md), or [C#](/docs/csharp/testing.md)
+
+* Learn more about [Copilot and AI-assisted testing in VS Code](/docs/copilot/overview.md)
+
+* Learn more about [using and configuring Tasks](/docs/editor/tasks.md)