GitHub Copilot Hands-On Lab

This is a simplified version of the GitHub Copilot Hands-On Lab for quickly ramp-up GitHub Copilot. The original version is available at GitHub Copilot Hands-On Lab

0. Prerequisites

• Config GitHub Copilot in you VS Code.
  • Install the GitHub Copilot extension @id:github.copilot
  • Install the GitHub Copilot Chat extension @id:GitHub.copilot-chat.
  • Sign in with your GitHub Enterprise account.
• Install VS Code C# Dev Kit extension @id:ms-dotnettools.csdevkit
• Download the SampleApps for the hands-on lab https://raw.githubusercontent.com/xiaoliangshi/GitHubCopilotHandsOnLab/refs/heads/main/Lab_SampleApps.zip

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1. Code Explanation & Document Generation

1.1 Code Explanation

1.1.1 Project explanation

1. Open the folder APL2007M2Sample1 with VS Code.

2. Open Chat Ctrl + Alt + i

3. Type the prompt to explain the project.

   @workspace Explain this project
   

1.1.2 File explanation

1. Open the file MainWindow.xaml.cs.

2. Ask copilot to explain the file.

   @workspace /explain #file:MainWindow.xaml.cs
   

1.1.3 Selected code explanation

1. In file MainWindow.xaml.cs, locate the method SumPageSizesAsync(), select the following code lines.

   IEnumerable<Task<int>> downloadTasksQuery =
       from url in _urlList
       select ProcessUrlAsync(url, _client);
   
   Task<int>[] downloadTasks = downloadTasksQuery.ToArray();

2. Right click to open the context menu Copilot > Explain.

1.1.4 Error explanation

1. In file MainWindow.xaml.cs, locate the method SumPageSizesAsync(), select the following code line.

   int[] lengths = Task.WhenAll(downloadTasks);

2. Open inline chat Ctrl + i, enter the prompt to ask for the error.

   /explain why is the selection causing an error
   

3. Right click to open the context menu Copilot > Fix. Fix the error by changing the code to:

   int[] lengths = await Task.WhenAll(downloadTasks);

1.2 Document Generation

1.2.1 Generate README file

1. Open the folder APL2007M2Sample1 with VS Code.

2. Open chat Ctrl + Alt + i, enter the prompt to generate a README file.

   @workspace generate a readme document that can be used as a repo description
   

1.2.2 Generate inline code documentation

1. Open the file MainWindow.xaml.cs.

2. Select all the code lines.

3. Open chat Ctrl + Alt + i, enter the prompt to generate a README file. Generate inline code documentation with copilot chat.

   @workspace generate inline code documentation for the selected code
   

4. Select the code lines for the function OnStartButtonClick, open inline edit with Ctrl + i Generate inline code documentation with inline chat

   /doc
   

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2. Dev Codes

2.1 Inline Code Generation from a comment

1. Open the folder APL2007M4PrimeService with VS Code.
2. In the file PrimeService.cs, locate the class PrimeService.
3. Add a comment above the class to generate the method IsPrime.

   // Generate a method named IsPrime that takes an integer as input and returns a boolean indicating whether the number is prime or not.

2.2 Inline Code generation from a method signature

1. In the file PrimeService.cs, locate the class PrimeService.
2. Add a method signature for the function IsPrime with the return type bool and input parameter int number.

   public bool IsPrime(int number)

2.3 Code Generation from an inline chat/GitHub Copilot chat

1. Open the file PrimeService.cs
2. Open the GitHub Copilot chat Ctrl + Alt + i

   Generate a method named IsPrime that takes an integer as input and returns a boolean indicating whether the number is prime or not.
   

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3. Unit Tests

3.1 Create unit tests using Chat view

1. Open the folder APL2007M4PrimeService with VS Code.
2. Select the code lines for the function IsPrime.
3. Open the GitHub Copilot chat Ctrl + Atl + i, add context PrimeService.UnitTests.csproj. and PrimeServiceTests.cs
4. Generate the unit test code with below prompt.

   /tests add unit tests for my code
   

5. Build & Run the tests

3.2 Create unit tests using inline chat

1. Curser to the function IsPrime, Open the GitHub Copilot chat Ctrl + i
2. Try the prompt below to generate unit tests.

   Create unit tests for the IsPrime method using the xUnit framework.
   

3.3 Create unit for specific cases

1. Open the GitHub Copilot chat Ctrl + Atl + i
2. Try the prompt below to generate unit tests for specific cases.

   @workspace are there any edge cases that should also be tested
   

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