Skip to content
cccskills
FreePublished on GitHub

write-tests

Write unit and integration tests. Use when the user says "write tests for this", "add test coverage", "how do I test this", "TDD", "red green refactor", "unit test this function", "test this module", "I need tests for", or has code that lacks tests - even if they don't explicitly say "write tests".

The English summary is being prepared. Showing the original description.

qa-aman/claude-skills
See how to install

Files included (1)

  • SKILL.md3.8 KB

SKILL.md (original)

Review the instructions the agent will receive before you install.

Overview

Based on "Test Driven Development By Example" by Kent Beck. Beck's core insight: tests are not a tax on development - they are the way you design. Writing the test first forces you to think about the interface before the implementation. Code written test-first tends to be more modular, more focused, and easier to change.

The TDD cycle: Red - Green - Refactor

  • Red: Write a failing test that defines desired behavior
  • Green: Write the minimum code to make the test pass
  • Refactor: Clean up the code without changing behavior. Tests prove you haven't broken anything.

Workflow

Step 1: Identify what to test

For a given function or module, list the behaviors to test:

  • The happy path (valid inputs - correct output)
  • Invalid inputs (what should fail gracefully)
  • Boundary conditions (empty, null, max, min)
  • Edge cases (concurrent calls, large data, unexpected types)

Don't write tests for implementation details - test behavior.

Step 2: Write the failing test first (Red)

Write a test that:

  • Has a descriptive name: test_<action>_<condition>_<expected_result>
  • Tests one behavior per test
  • Has clear Arrange / Act / Assert structure

Example in Python:

def test_withdraw_fails_when_balance_insufficient():
    # Arrange
    account = BankAccount(balance=50)
    # Act + Assert
    with pytest.raises(InsufficientFundsError):
        account.withdraw(100)

Run the test. Confirm it fails for the right reason (not a syntax error).

Step 3: Write minimum code to pass (Green)

Write the simplest code that makes the test pass. Do not gold-plate. Do not add features not tested yet. Run the test. Confirm it passes.

Step 4: Refactor (Refactor)

Clean up:

  • Remove duplication
  • Improve naming
  • Extract functions if needed

Run all tests after each refactor step. Tests are the safety net.

Step 5: Repeat for each behavior

Add one test at a time. After each Red-Green-Refactor cycle, all tests should pass.

Step 6: Write integration tests for wiring

Unit tests cover individual functions. Integration tests cover how components connect.

  • Test the integration point (API call, DB write, external service)
  • Use test doubles (mocks, stubs, fakes) for external dependencies in unit tests
  • Use real dependencies in integration tests

Anti-Patterns

1. Testing implementation instead of behavior Bad: Testing that a specific private method was called. Good: Testing that the observable output is correct given the input.

2. Tests that depend on each other Bad: Test B only works if Test A ran first. Good: Each test is fully independent. Any test can run in any order.

3. Writing tests after the code Bad: Code written first, tests added later to hit coverage targets. Good: Test first. The discipline is the point - it changes how you design.

4. One massive test instead of many small ones Bad: One test that covers 10 behaviors. Good: One behavior per test. When a test fails, you know exactly what broke.

Quality Checklist

  • Test names describe behavior: test_action_condition_result
  • Each test covers exactly one behavior
  • Tests follow Arrange / Act / Assert structure
  • Tests run in any order (no interdependencies)
  • Happy path, invalid inputs, and boundary conditions covered
  • External dependencies mocked in unit tests
  • Failing test written and confirmed failing before implementation
  • All tests pass after implementation and refactor

Reviews

No reviews yet. Tell others what you thought.

Comments

No login needed. Share how it worked for you, ask a question, or note where it did not run.

No comments yet. Be the first to write one.

Comments are published right away. Do not include personal information such as email addresses or phone numbers. Up to 2 URLs.

0 / 1,000 characters

This form is protected by reCAPTCHA, and the Google Privacy Policy and Terms of Service apply.

More skills from this repository

11-star-framework

Free

Rate any product, feature, or experience on the 11-star scale (Brian Chesky's Airbnb thought experiment). Use when user says "rate this experience", "11-star", "star rating", "experience audit", "how good is this", "experience rating", "product audit", "quality assessment", or wants to evaluate product quality and identify improvement paths. Also trigger when user wants to benchmark a feature, assess where a product stands, or map out what "great" looks like - even if they don't explicitly say "11-star".

The English summary is being prepared. Showing the original description.

qa-aman/claude-skills21Updated Oct 19, 2026

ab-copy-writer

Free

Generate A/B copy variants grounded in Eugene Schwartz's awareness and market-sophistication stages and John Caples' tested-headline discipline. Every variant declares its angle, the awareness stage it targets, and a falsifiable hypothesis, and the skill recommends which pair to test first and what delta counts as signal. Use when the user says "A/B test this", "write variants", "give me options", "test different angles", "copy variants", "ab copy", "test this headline", "multiple versions", "which version is better", or wants to test copy before publishing. For reviewing copy that already exists, see copy-review. For sample size and stopping rules, see growth-experiment. For diagnosing a page rather than its words, see page-cro. For full paid ad sets by platform, see ad-campaign-writer.

The English summary is being prepared. Showing the original description.

qa-aman/claude-skills21Updated Oct 19, 2026

ab-test-design

Free

Design statistically rigorous experiments to test data science hypotheses. Use when the user says "design an A/B test", "run an experiment", "test this hypothesis", "is this difference significant", "how many samples do I need", "randomized controlled trial", "causal inference", "uplift test", "holdout group", "significance test", "power calculation", "avoid p-hacking", or needs to determine whether an observed effect is real before making a product or model decision. For lean build-measure-learn product experiments without the statistics, use experiment-design instead.

The English summary is being prepared. Showing the original description.

qa-aman/claude-skills21Updated Oct 19, 2026

acceptance-criteria-writer

Free

Write measurable acceptance criteria for requirements or user stories. Use when the user says "write acceptance criteria", "definition of done", "how do we test this", "fit criteria", "given when then", "Gherkin scenarios", "what does done look like", "testable conditions", "how will we know this works" - even if they don't explicitly say "acceptance criteria".

The English summary is being prepared. Showing the original description.

qa-aman/claude-skills21Updated Oct 19, 2026

account-plan

Free

Build a strategic account plan for winning, retaining, or expanding a named account. Use when the user says "build an account plan", "strategic account planning", "how do I grow this account", "account expansion strategy", "whitespace analysis", "QBR prep", "key account review", "map the stakeholders in this account", "land and expand plan", "how do I break into [company]", or wants a structured strategy for a specific account.

The English summary is being prepared. Showing the original description.

qa-aman/claude-skills21Updated Oct 19, 2026

ad-campaign-writer

Free

Write paid ad copy for LinkedIn, Google, Meta, and YouTube. Produces multiple variants per platform, each targeting a different Eugene Schwartz awareness level and Cialdini persuasion principle. Use when the user asks for ad copy, ad variants, "write LinkedIn ads", Google ads, Meta ads, paid social copy, ad headlines, or wants creative for a paid campaign. Reads brand voice, ICP, and positioning from knowledge/. For organic social posts, see linkedin-post or social-calendar. For the landing page the ad points at, see landing-page-writer. For testing variants, see ab-copy-writer.

The English summary is being prepared. Showing the original description.

qa-aman/claude-skills21Updated Oct 19, 2026

See all skills by qa-aman

Report a problem with this skill