write-tests

name	write-tests
description	Write high-value tests in Codex by matching repository test conventions, prioritizing public behavior, and validating coverage gains without overfitting implementation details.
compatibility	Codex CLI with terminal access, Node.js test tooling, git, tokenlean CLI (npm i -g tokenlean)

Write Tests (Codex)

Write tests that protect behavior, not internals.

Workflow

Discover patterns -> Understand unit -> Design cases -> Implement tests -> Validate

1. Discover test patterns

tl parallel \
  "structure=tl structure" \
  "symbols=tl symbols test/" \
  "related=tl related <source-file>"

Match existing test style, helpers, and naming.

2. Understand code under test

tl parallel "symbols=tl symbols <source-file>" "exports=tl exports <source-file>"
tl snippet <function> <file>  # Read specific function implementations

Prioritize exported/public behavior.

3. Design cases

Cover:

• happy path
• error path
• edge cases (empty/null/boundary)

4. Implement tests

• Reuse existing fixtures/helpers.
• Mock only true external dependencies.
• Keep assertions specific and stable.

5. Validate

tl run "npm test"         # Token-efficient output — shows only failures

If available, run targeted test files first, then full suite.

Tips

• One clear behavior per test.
• Avoid brittle assertions tied to implementation details.
• Add regression tests for every bug fix when feasible.
• tl test-map <source-file> shows which test files cover a given source file.