Agent skill · software engineering · facebook
test
Use when you need to run tests for React core. Supports source, www, stable, and experimental channels.
Why this skill is useful
Adds specific commands for running tests in various React channels that the AI wouldn't reliably generate on its own.
What it needs
Requires yarn installed locally. About 1k tokens when loaded. Last updated 2026-08-06. 247,076 stars on the source repository.
What this skill does
Run tests for the React codebase. Arguments: $ARGUMENTS: Channel, flags, and test pattern Usage Examples: /test ReactFiberHooks - Run with source channel (default) /test experimental ReactFiberHooks - Run with experimental channel /test www ReactFiberHooks - Run with www-modern channel /test www variant false ReactFiberHooks - Test VARIANT=false /test stable ReactFiberHooks - Run with stable channel /test classic ReactFiberHooks - Run with www-classic channel /test watch ReactFiberHooks - Run in watch mode (TDD) Release Channels: (default) - Source/canary channel, uses ReactFeatureFlags.js defaults experimental - Source/experimental channel with EXPERIMENTAL flags = true www - www-modern channel with VARIANT flags = true www variant false - www channel with VARIANT flags = false stable - What ships to npm classic - Legacy www-classic (rarely needed) Instructions: 1. Parse channel from arguments (default: source) 2. Map to yarn command: (default) → yarn test --silent --no-watchman <pattern> experimental → yarn test -r=experimental --silent --no-watchman <pattern> stable → yarn test-stable --silent --no-watchman <pattern> classic → yarn test-classic --silent --no-watchman <pattern> www → yarn test-www --silent --no-watchman <pattern> www variant false → yarn test-www --variant=false --silent --no-watchman <pattern> 3. Report test results and any failures Hard Rules: 1. Use --silent to see failures - This limits the test output to only failures. 2. Use --no-watchman - This is a common failure in sandboxing. Common Mistakes: Running without a pattern - Runs ALL tests, very slow. Always specify a pattern. Forgetting both www variants - Test www AND www variant false for VARIANT flags. Test skipped unexpectedly - Check for @gate pragma; see feature-flags skill.
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills facebook/test