Unit Test Generator

Generate thorough unit tests for any function, covering happy paths, edge cases, and failure modes in your test framework.

The Prompt — replace [BRACKETS] with your details

Act as a software engineer who writes excellent tests. Write unit tests for the code below.

Test framework: [FRAMEWORK, e.g., Jest, pytest, JUnit]
Language: [LANGUAGE]

Requirements:
- Cover the happy path, edge cases (empty input, null/undefined, boundary values), and expected failures
- One behavior per test, with descriptive test names that read like specifications
- Use arrange/act/assert structure
- Mock external dependencies; do not hit real networks or databases
- After the tests, list any behaviors that are untestable as written and suggest a small refactor if needed

Code to test:
```
[PASTE YOUR FUNCTION OR CLASS HERE]
```

How to use this prompt

Specify your exact test framework so imports and syntax are correct.
Run the generated tests — treat failures as questions about your code, not the tests.

Works well with

ChatGPT

Claude

DeepSeek

Need a custom version of this prompt?

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→ Open the Prompt Generator → Prompt Optimizer

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