# Testing automation

> File-specific instructions for writing unit tests.

- 网址：https://funcoding.ai/agents/github-copilot/tutorials/customization-library/custom-instructions/testing-automation/
- 来源：GitHub Copilot 官方文档原文（英文），CC-BY-4.0 许可，同步于 2026-10-11
- 官方原文：https://docs.github.com/en/copilot/tutorials/customization-library/custom-instructions/testing-automation

---
<div class="callout callout-note">

* The examples in this library are intended for inspiration—you are encouraged to adjust them to be more specific to your projects, languages, and team processes.
* For community-contributed examples of custom instructions for specific languages and scenarios, see the [Awesome GitHub Copilot Customizations](https://github.com/github/awesome-copilot/blob/main/docs/README.instructions.md) repository.
* You can apply custom instructions across different scopes, depending on the platform or IDE where you are creating them. For more information, see "[AUTOTITLE](https://funcoding.ai/agents/github-copilot/concepts/prompting/response-customization/)."

</div>

This example shows a path-specific `python-tests.instructions.md` file that applies only to Python test files in your repository, using the `applyTo` field. For more information about path-specific instructions files, see [AUTOTITLE](https://funcoding.ai/agents/github-copilot/how-tos/copilot-on-github/customize-copilot/add-custom-instructions/add-repository-instructions/#creating-path-specific-custom-instructions).

````text copy
---
applyTo: "tests/**/*.py"
---

When writing Python tests:

## Test Structure Essentials
- Use pytest as the primary testing framework
- Follow AAA pattern: Arrange, Act, Assert
- Write descriptive test names that explain the behavior being tested
- Keep tests focused on one specific behavior

## Key Testing Practices
- Use pytest fixtures for setup and teardown
- Mock external dependencies (databases, APIs, file operations)
- Use parameterized tests for testing multiple similar scenarios
- Test edge cases and error conditions, not just happy paths

## Example Test Pattern
```python
import pytest
from unittest.mock import Mock, patch

class TestUserService:
    @pytest.fixture
    def user_service(self):
        return UserService()

    @pytest.mark.parametrize("invalid_email", ["", "invalid", "@test.com"])
    def test_should_reject_invalid_emails(self, user_service, invalid_email):
        with pytest.raises(ValueError, match="Invalid email"):
            user_service.create_user({"email": invalid_email})

    @patch('src.user_service.email_validator')
    def test_should_handle_validation_failure(self, mock_validator, user_service):
        mock_validator.validate.side_effect = ConnectionError()

        with pytest.raises(ConnectionError):
            user_service.create_user({"email": "test@example.com"})
```
````