Test Generator

Generate unit tests for a given source file by analyzing its public interface, control flow, and error handling paths.

Why This Exists

Writing tests from scratch is tedious and developers skip it. This skill generates a solid starting point that covers the obvious cases, so the developer can focus on the tricky edge cases that require domain knowledge.

Steps

Step 1: Analyze the Source File

Read the source file. Identify:

• Public functions and methods
• Input parameter types and ranges
• Return types
• Error conditions (throws, error returns, panics)
• External dependencies (imports, API calls)

Step 2: Design Test Cases

For each public function, generate test cases for:

• Happy path with typical inputs
• Boundary values (empty string, zero, max int)
• Error cases (nil input, invalid format)
• If the function has side effects, test those separately

Step 3: Write Tests

Create the test file following project conventions:

• Match the project's test framework (detect from existing tests or config)
• Use the project's assertion style
• Follow the naming convention of existing tests

Write the test file to the standard test location for the language.

Step 4: Run and Fix

Run the generated tests:

# Detect and run appropriate test command

If any tests fail due to incorrect assumptions, fix them. Report which tests pass and which needed adjustment.

Tips

• The generated tests are a starting point, not a final product
• Review the generated tests for correctness before committing
• Edge cases that require domain knowledge need manual attention