Skip to content
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension


Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Original file line number Diff line number Diff line change
Expand Up @@ -30,38 +30,21 @@ Thankfully, {% data variables.product.prodname_copilot_short %} can help debug y

When you run bugged code, you'll often receive an error message. The message tells you the file and line where the error occurred and briefly describes what went wrong. However, error messages can be confusing. To fully understand and fix the bug, we can ask {% data variables.product.prodname_copilot_short %} for help.

Let's try this out with the [`bugged_dice_battle.py`](https://github.com/new2code/debug-with-copilot/blob/main/bugged_dice_battle.py) file in the [`new2code/debug-with-copilot`](https://github.com/new2code/debug-with-copilot) repository. This program simulates a dice battle between two players using the following code:
Let's try this out with an example repository: [`new2code/debug-with-copilot`](https://github.com/new2code/debug-with-copilot).

```python
# Import the random module to easily generate pseudo-random numbers
import random
#### Cloning the example repository

# Define a function that simulates a dice battle between two players
def dice_battle():

# Generate random numbers between 1 and 6 for each player's die roll
die_1 = random.randint(1, 6)
die_2 = random.randint(1, 6)

# Compare the die rolls and return the result as a string
if die_1 > die_2:
return "Player 1 rolled a " + die_1 + " and Player 2 rolled a " + die_2 + ". Player 1 wins!"
elif die_1 < die_2:
return "Player 1 rolled a " + die_1 + " and Player 2 rolled a " + die_2 + ". Player 2 wins!"
else:
return "Player 1 rolled a " + die_1 + " and Player 2 rolled a " + die_2 + ". It's a tie!"

print(dice_battle())
```

First, we need to create a local copy of the example repository:
First, we need to create a local copy of the repository:

1. [Start cloning the new2code/debug-with-copilot repository](vscode://vscode.git/clone?url=https://github.com/new2code/debug-with-copilot) in {% data variables.product.prodname_vscode_shortname %}. <!-- markdownlint-disable-line GHD003 -->
1. Choose a location to save the repository on your computer, then click **Select as Repository Destination**.
1. When prompted, open the repository.

Now that we've cloned the repository, let's run `bugged_dice_battle.py` to see the output:
#### Running the bugged file

Now, let's run the [`bugged_dice_battle.py`](https://github.com/new2code/debug-with-copilot/blob/main/bugged_dice_battle.py) file. This program simulates a dice battle between two players.

1. In {% data variables.product.prodname_vscode_shortname %}, open and review the `bugged_dice_battle.py` file.
1. Open the Command Palette by pressing <kbd>Ctrl</kbd>+<kbd>Shift</kbd>+<kbd>P</kbd> (Windows/Linux) or <kbd>Cmd</kbd>+<kbd>Shift</kbd>+<kbd>P</kbd> (Mac).
1. Type `Terminal: Create New Terminal` and press <kbd>Enter</kbd>.
1. In the terminal tab, paste the following command.
Expand All @@ -84,38 +67,31 @@ Unfortunately, we get some error text in our terminal ending with the following

> TypeError: can only concatenate str (not "int") to str

To understand what this means, press <kbd>Ctrl</kbd>+<kbd>Alt</kbd>+<kbd>I</kbd> (Windows/Linux) or <kbd>Command</kbd>+<kbd>Shift</kbd>+<kbd>I</kbd> (Mac) to **open {% data variables.product.prodname_copilot_chat_short %}**, then paste and send the following prompt:
#### Debugging the file

To understand what this error means, press <kbd>Ctrl</kbd>+<kbd>Alt</kbd>+<kbd>I</kbd> (Windows/Linux) or <kbd>Command</kbd>+<kbd>Shift</kbd>+<kbd>I</kbd> (Mac) to **open {% data variables.product.prodname_copilot_chat_short %}**, then paste and send the following prompt:

```text copy
Explain in depth why my code produces the following error and how I can fix it:

TypeError: can only concatenate str (not "int") to str
```

{% data variables.product.prodname_copilot_short %} will respond that the error occurs because we are trying to concatenate the integers `die_1` and `die_2` to strings, and you can only concatenate strings to strings. It will then provide an updated version of our code that fixes the bug by using the `str()` function to convert the integers to strings before concatenating them.
{% data variables.product.prodname_copilot_short %} will respond that the error occurs because we are trying to concatenate the integers `die_1` and `die_2` to strings, and you can only concatenate strings to strings.

It will also provide an **updated version of our code** that fixes the bug by using the `str()` function to convert the integers to strings before concatenating them. Practice the final step of debugging by applying {% data variables.product.prodname_copilot_short %}'s suggestion to the file.

### Debugging an incorrect output with {% data variables.product.prodname_copilot %}

Sometimes, bugged code runs without throwing any errors, but the output is clearly incorrect. In this case, debugging can be more difficult because {% data variables.product.prodname_vscode_shortname %} can't tell you the location or description of the bug.

For these "invisible" bugs, {% data variables.product.prodname_copilot_short %} is particularly useful. Let's get some hands-on experience using the [`bugged_factorial_finder.py`](https://github.com/new2code/debug-with-copilot/blob/main/bugged_factorial_finder.py) file in the [`new2code/debug-with-copilot`](https://github.com/new2code/debug-with-copilot) repository. The Python program is supposed to calculate a factorial, and it contains the following code:

```python
# Initialize the factorial result to 1
factorial = 1

# Initialize the input number to 6
number = 6
For these "invisible" bugs, {% data variables.product.prodname_copilot_short %} is particularly useful. Let's get some hands-on experience with the other file in our example repository: `bugged_factorial_finder.py`. It's a Python program that's supposed to calculate a factorial.

# Loop from 1 to number (inclusive) and multiply factorial by each number
for i in range(1, number + 1):
factorial *= factorial * i
#### Running the bugged file

print(f"The factorial of {number} is {factorial}")
```

Since we've already cloned the repository locally, let's run `bugged_factorial_finder.py` to see the output:
First, let's run the program to see the incorrect output:

1. Open and review the `bugged_factorial_finder.py` file.
1. In the terminal you created earlier, paste the following command.
Windows:

Expand All @@ -133,15 +109,17 @@ Since we've already cloned the repository locally, let's run `bugged_factorial_f

Unfortunately, the code isn't working as expected. We want it to return `720`, the correct value of 6 factorial, but the output is much higher than that.

To understand what went wrong, with the `bugged_factorial_finder.py` file open in {% data variables.product.prodname_vscode_shortname %}, open {% data variables.product.prodname_copilot_chat_short %} and send the following prompt:
#### Debugging the file

To understand what went wrong, open {% data variables.product.prodname_copilot_chat_short %} and send the following prompt:

```text copy
Why is the output of this code so much higher than expected? Please explain in depth and suggest a solution.
```

{% data variables.product.prodname_copilot_short %} will point out that, because we're using the `*=` operator, we're actually multiplying `factorial` by both `i` **and** `factorial`. In other words, we're multiplying by an extra `factorial` for each iteration of the loop.

To fix this error, {% data variables.product.prodname_copilot_short %} will suggest code that removes the extra `factorial` from the equation, or that changes the `*=` operator to `=`.
To fix this error, {% data variables.product.prodname_copilot_short %} will suggest code that removes the extra `factorial` from the equation, or that changes the `*=` operator to `=`. Make that change now!

## Debugging your own project

Expand Down
80 changes: 40 additions & 40 deletions package-lock.json

Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.

2 changes: 1 addition & 1 deletion package.json
Original file line number Diff line number Diff line change
Expand Up @@ -301,7 +301,7 @@
"mdast-util-to-markdown": "2.1.0",
"mdast-util-to-string": "^4.0.0",
"morgan": "^1.10.0",
"next": "^15.2.3",
"next": "^15.2.4",
"ora": "^8.0.1",
"parse5": "7.1.2",
"quick-lru": "7.0.0",
Expand Down