Exercise - Debug code with Copilot Chat

  • 10 minutes

Copilot Chat allows you to interact with Copilot using natural language. In this exercise, you'll use Copilot Chat to debug and improve code in the Trie project. Let's get started!

Important

This module requires the Github Copilot Chat extension, which is currently in public beta and subject to changes.

Use Copilot Chat to debug code

  1. Open the Trie.cs file

  2. Navigate to the LevenshteinDistance method

    The Levenshtein distance is a method for measuring the differences between two strings. The Levenshtein distance between two strings is defined as the minimum number of edits needed to transform one string into the other. The edit operations include insertion, deletion, or substitution of a character.

    In this code, the Levenshtein distance is calculated incorrectly. Let's use Copilot Chat to fix the error.

  3. Select all of the code for the LevenshteinDistance method

  4. Right click the selected code. Under Generate Code, select Review

    Copilot should detect that the Levenshtein distance calculation is incorrect, and suggest incremental fixes.

  5. Click Apply and Go To Next to apply the fixes and continue reviewing the code until all suggestions have been applied.

Use Copilot Chat to improve code

You can use Copilot Chat to improve code by adding new features or refactoring existing code. Let's use Copilot Chat to improve the PrintTrie method.

  1. Open the Program.cs file

  2. Navigate to the PrintTrie method

    This method prints the contents of the trie to the console.

  3. Select all of the code for the PrintTrie method

  4. Right click the selected code and select Inline Chat

  5. In the textbox, enter "Improve this code by separating the words into five columns"

  6. Wait for Copilot to generate the new code.

    Copilot should suggest code that prints the words in five columns.

  7. Click Accept to apply the changes.

Check your work

In this task, you'll test the methods you created with Copilot to verify that they work as expected.

  1. Open the Program.cs file

  2. Uncomment the GetSpellingSuggestions method call:

    Trie dictionary = InitializeTrie(words);
// SearchWord();
// PrefixAutocomplete();
// DeleteWord();
GetSpellingSuggestions();

  3. In the file explorer, right click the Program.cs file and click Open in Integrated Terminal

  4. Enter dotnet run to run the program.

  5. Enter a misspelled word to generate spelling suggestions for, such as "cae"

  6. Verify that your output is similar to the following

    The dictionary contains the following words:
as             cars           follows        monday         plans
astronaut      cares          from           monster        the
asteroid       careful        front          place          their
are            carefully      mellow         plan           they
around         for            mean           planet         there
cat            forgot         money          planets        towards

Enter a word to get spelling suggestions for, or press Enter to exit.
cae
Spelling suggestions for "cae":
cat
cars
cares

    If your code displays different results, review your code to find your error and make updates. Run the code again to see if you've fixed the problem. Continue updating and running your code until your code produces the expected results.

  7. Comment out the GetSpellingSuggestions method call.