# Unit Test

> Write and review xterm.js unit tests with project conventions. Use when editing `*.test.ts` files or when asked for test authoring guidelines.

- Skill: `xtermjs/unit-test` (Agent Skill)
- Install (CLI): `npx skillmds@latest add xtermjs/unit-test`
- Raw SKILL.md: https://api.skillmd.com/api/skills/xtermjs/unit-test/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: xtermjs (https://skillmd.com/u/xtermjs)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/xtermjs/unit-test

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# Unit Test Instructions

When writing unit tests, follow these rules:

- When writing unit tests for addons, always create a real xterm.js instance instead of mocking it.
- Prefer `assert.ok` over `assert.notStrictEqual` when checking something is undefined or not.
- Avoid comments as most tests should be self-documenting.