vitest-testing-patterns

vitest-testing-patterns is a skill for Claude Code from punkadillo/figma-code-composer. It costs 25 tokens per session (2,203 once invoked), scanned A, a copy of vitest-performance, MIT.

A guide to Vitest, a testing tool for TypeScript and JavaScript code, covering unit tests, test doubles such as mocks and spies, and tests that run in a browser.

In plain words
What is it for?
Writing unit tests, replacing dependencies with mocks or spies, and testing browser-based behavior with Vitest.
Why use it?
It helps developers choose suitable testing patterns and check code behavior reliably.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Good fit Writing unit tests, replacing dependencies with mocks or spies, and testing browser-based behavior with Vitest.

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Install with agentmods
npx agentmods add skills/punkadillo/figma-code-composer/vitest-testing-patterns
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add punkadillo/figma-code-composer --skill vitest-testing-patterns
Clone the repo
git clone --depth 1 https://github.com/punkadillo/figma-code-composer

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for vitest-testing-patterns

README.md
[![agentmods](https://agentmods.dev/badge/skills/punkadillo/figma-code-composer/vitest-testing-patterns.svg)](https://agentmods.dev/skills/punkadillo/figma-code-composer/vitest-testing-patterns)
Your own site
<a href="https://agentmods.dev/skills/punkadillo/figma-code-composer/vitest-testing-patterns"><img src="https://agentmods.dev/badge/skills/punkadillo/figma-code-composer/vitest-testing-patterns.svg" alt="Measured on agentmods" height="20"></a>
Per session 25 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,203 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 95% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00025 $0.02203
Opus 5 $0.00013 $0.01102
Sonnet 5 $0.00005 $0.00441
Haiku 4.5 $0.00003 $0.00220

Measured 4d ago against content hash cf2c895f210a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

vitest-testing-patterns scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

95% identical to vitest-performance — 8 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.figma-pipeline/skills/vitest-testing-patterns/SKILL.md · 496 lines

How it starts

The opening of the file, as written. The whole thing — 496 lines — stays where its author put it; the contents beside it link to each section on GitHub.

vitest testing patterns

Master Vitest testing patterns including unit tests, mocks, spies, and browser mode testing. This skill provides comprehensive coverage of essential concepts, patterns, and best practices for professional Vitest development.

Overview

Vitest is a powerful tool for typescript development, providing robust capabilities for maintaining code quality and ensuring reliable software delivery. This skill covers the fundamental through advanced aspects of working with Vitest.

Installation and Setup

Basic Installation

Setting up Vitest requires proper installation and configuration in your development environment.

# Installation command specific to Vitest
# Follow official documentation for latest version

Project Configuration

Create appropriate configuration files and setup for your project structure:

  • Configuration file setup
  • Project structure organization
  • Team collaboration setup
  • CI/CD integration preparation

Core Concepts

Fundamental Principles

Understanding the core principles of Vitest is essential for effective usage:

  1. Architecture - How Vitest is structured and operates
  2. Configuration - Setting up and customizing behavior
  3. Integration - Working with other tools and frameworks
  4. Best Practices - Industry-standard approaches

Key Features

Vitest provides several key features that make it valuable:

  • Feature 1: Core functionality
  • Feature 2: Advanced capabilities
  • Feature 3: Integration options
  • Feature 4: Performance optimization
  • Feature 5: Extensibility

Configuration Strategy

Proper configuration ensures Vitest works optimally:

  • Environment-specific setup
  • Team standards enforcement
  • Performance tuning
  • Error handling configuration

Advanced Usage

For complex scenarios, Vitest offers advanced capabilities:

  • Custom extensions
  • Advanced patterns
  • Performance optimization
  • Scalability considerations

Code Examples

Example 1: Basic Setup

Read the full file on GitHub · 496 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 4d ago First seen · 496 lines · 25 tokens per session scan A cf2c895f210a

Subscribe to this mod's changes

vitest-testing-patterns is a skill published in the GitHub repository punkadillo/figma-code-composer (3 stars, last pushed 20d ago), licensed MIT. It adds 25 tokens to every session and 2,203 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 95% identical to vitest-performance, differing in 8 lines, and is treated as a copy.

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