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Bun Test Basics

Use for bun:test syntax, assertions, describe/it, test.skip/only/each, and basic patterns.

By secondsky
20230Updated 1 week agoTypeScriptMIT

Skill Content

# Bun Test Basics

Bun ships with a fast, built-in, Jest-compatible test runner. Tests run with the Bun runtime and support TypeScript/JSX natively.

## Quick Start

```bash
# Run all tests
bun test

# Run specific file
bun test ./test/math.test.ts

# Run tests matching pattern
bun test --test-name-pattern "addition"
```

## Writing Tests

```typescript
import { test, expect, describe } from "bun:test";

test("2 + 2", () => {
  expect(2 + 2).toBe(4);
});

describe("math", () => {
  test("addition", () => {
    expect(1 + 1).toBe(2);
  });

  test("subtraction", () => {
    expect(5 - 3).toBe(2);
  });
});
```

## Test File Patterns

Bun discovers test files matching:
- `*.test.{js|jsx|ts|tsx}`
- `*_test.{js|jsx|ts|tsx}`
- `*.spec.{js|jsx|ts|tsx}`
- `*_spec.{js|jsx|ts|tsx}`

## Test Modifiers

```typescript
// Skip a test
test.skip("not ready", () => {
  // won't run
});

// Only run this test
test.only("focus on this", () => {
  // other tests won't run
});

// Placeholder for future test
test.todo("implement later");

// Expected to fail
test.failing("known bug", () => {
  throw new Error("This is expected");
});
```

## Parameterized Tests

```typescript
test.each([
  [1, 1, 2],
  [2, 2, 4],
  [3, 3, 6],
])("add(%i, %i) = %i", (a, b, expected) => {
  expect(a + b).toBe(expected);
});

// With objects
test.each([
  { a: 1, b: 2, expected: 3 },
  { a: 5, b: 5, expected: 10 },
])("add($a, $b) = $expected", ({ a, b, expected }) => {
  expect(a + b).toBe(expected);
});
```

## Concurrent Tests

```typescript
// Run tests in parallel
test.concurrent("async test 1", async () => {
  await fetch("/api/1");
});

test.concurrent("async test 2", async () => {
  await fetch("/api/2");
});

// Force sequential when using --concurrent
test.serial("must run alone", () => {
  // runs sequentially
});
```

## Common Matchers

```typescript
// Equality
expect(value).toBe(4);           // Strict equality
expect(obj).toEqual({ a: 1 });   // Deep equality
expect(value).toStrictEqual(4);  // Strict + type

// Truthiness
expect(value).toBeTruthy();
expect(value).toBeFalsy();
expect(value).toBeNull();
expect(value).toBeDefined();
expect(value).toBeUndefined();

// Numbers
expect(value).toBeGreaterThan(3);
expect(value).toBeGreaterThanOrEqual(3);
expect(value).toBeLessThan(5);
expect(value).toBeCloseTo(0.3, 5);  // Floating point

// Strings
expect(str).toMatch(/pattern/);
expect(str).toContain("substring");
expect(str).toStartWith("Hello");
expect(str).toEndWith("world");

// Arrays
expect(arr).toContain(item);
expect(arr).toContainEqual({ a: 1 });
expect(arr).toHaveLength(3);

// Objects
expect(obj).toHaveProperty("key");
expect(obj).toHaveProperty("key", value);
expect(obj).toMatchObject({ a: 1 });

// Exceptions
expect(() => fn()).toThrow();
expect(() => fn()).toThrow("message");
expect(() => fn()).toThrow(CustomError);

// Async
await expect(promise).resolves.toBe(value);
await expect(promise).rejects.toThrow();

// Negation
expect(value).not.toBe(5);
```

## CLI Options

```bash
# Timeout per test (default 5000ms)
bun test --timeout 20

# Bail after N failures
bun test --bail
bun test --bail=10

# Watch mode
bun test --watch

# Random order
bun test --randomize
bun test --seed 12345

# Concurrent execution
bun test --concurrent
bun test --concurrent --max-concurrency 4

# Filter by name
bun test -t "pattern"
```

## Output Reporters

```bash
# Dots (compact)
bun test --dots

# JUnit XML (CI/CD)
bun test --reporter=junit --reporter-outfile=./results.xml
```

## Common Errors

| Error | Cause | Fix |
|-------|-------|-----|
| `Test timeout` | Test exceeds 5s | Use `--timeout` or optimize |
| `No tests found` | Wrong file pattern | Check file naming |
| `expect is not defined` | Missing import | Import from `bun:test` |
| `Assertion failed` | Test failure | Check expected vs actual |

## When to Load References

Load `references/matchers.md` when:
- Need complete matcher reference
- Custom matcher patterns

Load `references/cli-options.md` when:
- Full CLI flag reference
- Advanced execution options

How to use

  1. Copy the skill content above
  2. Create a .claude/skills directory in your project
  3. Save as .claude/skills/claude-skills-bun-test-basics.md
  4. Use /claude-skills-bun-test-basics in Claude Code to invoke this skill

README

View on GitHub

Claude Code Skills Collection

142 production-ready skills for Claude Code CLI

Version 3.5.0 | Last Updated: 2026-07-18

<div align="center">

šŸ”Œ Platform Support

This repository uses Claude Plugin Patterns ā€” natively supported by:

PlatformStatusNotes
Claude Codeāœ… NativeFull marketplace support
Factory Droidāœ… NativeFull marketplace support
</div> **For all other Platforms like opencode, codex and others, you can use https://github.com/enulus/OpenPackage **

A curated collection of battle-tested skills for building modern web applications with Cloudflare, AI integrations, React, Tailwind, and more.

PS: if skills.sh warns about any skill: Their scan process is a outdated LLM which flags newest versions pins (like in ZOD) as non existent and by that potentially malicous.

Quick Start

Marketplace Installation (Recommended)

# Add the marketplace
/plugin marketplace add https://github.com/secondsky/claude-skills

# Install individual skills as needed
/plugin install cloudflare-d1@claude-skills
/plugin install tailwind-v4-shadcn@claude-skills
/plugin install gemini-cli@claude-skills

See MARKETPLACE.md for complete catalog of all 139 skills.

Bulk Installation (Contributors)

# Clone the repository
git clone https://github.com/secondsky/claude-skills.git
cd claude-skills

# Install all 139 skills at once
./scripts/install-all.sh

# Or install individual skills
./scripts/install-skill.sh cloudflare-d1

Repository Structure

This repository contains 139 production-tested skills for Claude Code, each focused on a specific technology or capability.

Individual Skills: Each skill is a standalone unit with:

  • SKILL.md - Core knowledge and guidance
  • Templates - Working code examples
  • References - Extended documentation
  • Scripts - Helper utilities

Installation Options:

  1. Individual - Install only the skills you need via marketplace
  2. Bulk - Install all 139 skills using ./scripts/install-all.sh

Available Skills (139 Individual Skills)

Each skill is individually installable. Install only the skills you need.

Full Catalog: See MARKETPLACE.md for detailed listings.

Categories

CategorySkillsExamples
tooling22turborepo, plan-interview, code-review
frontend26nuxt-v4, nuxt-v5, tailwind-v4-shadcn, tanstack-query, nuxt-studio, maz-ui, threejs
cloudflare21cloudflare-d1, cloudflare-workers-ai, cloudflare-agents
api16api-design-principles, graphql-implementation
ai7gemini-cli, ml-model-training, tanstack-ai
web10hono-routing, firecrawl-scraper, web-performance
security5csrf-protection, xss-prevention
mobile5react-native-app, react-native-skills
woocommerce4woocommerce-backend-dev
testing4vitest-testing, playwright-testing
design4design-review, design-system-creation
auth4better-auth
architecture3microservices-patterns, architecture-patterns
data2recommendation-engine, recommendation-system
cms2hugo, wordpress-plugin-core
database1drizzle-orm-d1
seo2seo-optimizer, seo-keyword-cluster-builder
documentation1technical-specification

How It Works

Auto-Discovery

Claude Code automatically checks ~/.claude/skills/ for relevant skills before planning tasks:

User: "Set up a Cloudflare Worker with D1 database"
           ā†“
Claude: [Checks skills automatically]
           ā†“
Claude: "Found cloudflare-d1 skills.
         These prevent 12 documented errors. Use them?"
           ā†“
User: "Yes"
           ā†“
Result: Production-ready setup, zero errors, ~65% token savings

Note: Due to token limits, not all skills may be visible at once. See āš ļø Important: Token Limits below.

Skill Structure

Each skill includes:

skills/[skill-name]/
ā”œā”€ā”€ SKILL.md              # Complete documentation
ā”œā”€ā”€ .claude-plugin/
ā”‚   ā””ā”€ā”€ plugin.json       # Plugin metadata
ā”œā”€ā”€ templates/            # Ready-to-copy templates
ā”œā”€ā”€ scripts/              # Automation scripts
ā””ā”€ā”€ references/           # Extended documentation

Recent Additions

July 2026

Offensive Security (new category):

  • cybersecurity ā€” Unified OSS-only cybersecurity skill with progressive disclosure. Fuses 7 community skills (mukul975 business-logic/XSS/host-header/forced-browsing/open-redirect, rysweet/amplihack cybersecurity-analyst, Aradotso security-detections-mcp) ported to fully open-source tooling (OWASP ZAP, Dalfox, ffuf, Nuclei, mitmproxy, interact.sh, Semgrep, Sigma). Covers threat modeling (STRIDE/PASTA/VAST, MITRE ATT&CK), web-vuln testing, SAST, code audit, AI/LLM-app security, and detection engineering. Live-target testing is gated behind an authorization disclaimer; static analysis, code review, and threat modeling are always available. Cross-references the 5 existing defensive security plugins (csrf-protection, xss-prevention, vulnerability-scanning, security-headers-configuration, defense-in-depth-validation) for remediation. Integrates 20 Aradotso dev-security skills across 5 grouped reference docs.

May 2026

Supply Chain Security (cross-cutting):

  • dependency-upgrade expanded with Socket CLI integration ā€” proactive malicious package detection, typosquatting alerts, and CI/CD security gates. New 418-line reference guide, 2 GitHub Actions templates, and expanded supply chain security comparison (3 tools)
  • 31 skills now include "Secure Installation" guidance ā€” contextually-tailored security sections across all high-risk skill categories (scaffolding, MCP/agent SDKs, multi-provider installs, Docker, CI/CD). Covers 8 Bun skills, 5 Nuxt skills, 6 Cloudflare skills, 4 AI/agent skills, and 8 frontend/tooling skills
  • Supply chain security is now a first-class cross-cutting concern woven into the skill collection ā€” not a standalone topic

February - April 2026

Full-Stack Frameworks:

  • nuxt-v5 (v1.0.0) - Full Nuxt 5 support with 4 skills (core, data, server, production), 3 diagnostic agents, and interactive setup wizard
  • threejs (v1.0.0) - 3D web graphics: scenes, geometries, shaders, animations, post-processing

Infrastructure:

  • JSON schema validation - Automated plugin.json validation with CI support
  • GitHub issue templates - Skill-specific issue templates for bug reports, feature requests, and submissions

Plugin Enhancements:

  • mutation-testing - Added Bun native runner support
  • dependency-upgrade - Added supply chain security content

December 2025 - January 2026

Frontend Expansion:

  • nuxt-studio (v1.0.0) - Visual CMS for Nuxt Content with live preview, OAuth auth, and R2 storage integration
  • maz-ui (v1.0.0) - 50+ Vue/Nuxt components with theming, i18n, form generation, and 14 composables

Developer Workflow:

  • plan-interview (v2.0.0) - Adaptive interview-driven spec generation with autonomous quality review
  • turborepo (v2.8.0) - Updated to official Vercel skill with enhanced monorepo build optimization

Mobile Development:

  • react-native-skills (v1.0.0) - React Native & Expo best practices with performance optimization patterns

Enhanced Authentication:

  • better-auth (v2.2.0) - Expanded to 18 framework integrations with 30+ authentication plugins

āš ļø Important: Token Limits

Skill Visibility Constraint

Claude Code has a 15,000 character limit for the total size of skill descriptions in the system prompt. This limit also applies to commands and agents.

What this means:

  • Not all 139 skills may be visible in Claude's context at once
  • Skills are loaded based on relevance and available token budget
  • You can verify how many skills Claude currently sees by asking: "How many skills do you see in your system prompt?"

Checking Visible Skills

To verify which skills are currently loaded:

# Ask Claude Code directly
"Check what skills/plugins you see in your system prompt"

Claude will report something like: "85 of 139 skills visible due to token limits"

Workaround: Increase Token Budget

You can double the headroom for skill descriptions by setting an environment variable:

# Increase limit to 30,000 characters
export SLASH_COMMAND_TOOL_CHAR_BUDGET=30000

# Then launch Claude Code
claude

This gives you approximately 2x more skill visibility in the system prompt.

Note: This is a temporary workaround. The Claude Code team is working on better solutions for skill discovery and loading.

Token Efficiency

MetricManual SetupWith SkillsSavings
Average Tokens12,000-15,0004,000-5,000~65%
Typical Errors2-4 per service0 (prevented)100%
Setup Time2-4 hours15-45 minutes~80%

Across all 139 skills: 400+ documented errors prevented.

Contributing

Prerequisites for Contributors

Install the official plugin development toolkit:

/plugin install plugin-dev@claude-code-marketplace

This provides:

  • /plugin-dev:create-plugin command (8-phase guided workflow)
  • 7 comprehensive skills (hooks, MCP, structure, agents, commands, skills)
  • 2 specialized agents (agent-creator, plugin-validator)

Quick Steps

  1. Create skill directory in plugins/
  2. Add SKILL.md with YAML frontmatter
  3. Run ./scripts/sync-plugins.sh
  4. Submit pull request

See CONTRIBUTING.md and PLUGIN_DEV_BEST_PRACTICES.md for detailed guidelines.

Documentation

DocumentPurpose
START_HERE.mdStart here! Quick navigation guide
PLUGIN_DEV_BEST_PRACTICES.mdRepository-specific best practices (marketplace, budget, quality)
MARKETPLACE.mdFull skill catalog and installation guide
MARKETPLACE_MANAGEMENT.mdTechnical infrastructure (plugin.json, scripts, validation)
CLAUDE.mdProject context and development standards
CONTRIBUTING.mdContribution guidelines

Links

Built with ā¤ļø by Claude Skills Maintainers

View source on GitHub