bun-test-mocking SKILL.md skillA
bun-test-mocking from secondsky/claude-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add secondsky/claude-skills/bun-test-mocking@v1.0.0Pins v1.0.0 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- secondsky/claude-skills
- Path
plugins/bun/skills/bun-test-mocking/SKILL.md- Versions recorded
- 3
- Latest version
- v1.0.0, committed Apr 2, 2026
- First version recorded
- Dec 29, 2025
- Size
- 5,374 bytes
- Repository stars
- 247
- License
- MIT
Use for mock functions in Bun tests, spyOn, mock.module, implementations, and test doubles.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Bun Test Mocking
Bun provides Jest-compatible mocking with `mock()`, `spyOn()`, and module mocking.
## Mock Functions
```typescript
import { test, expect, mock } from "bun:test";
// Create mock function
const fn = mock(() => "original");
test("mock function", () => {
fn("arg1", "arg2");
expect(fn).toHaveBeenCalled();
expect(fn).toHaveBeenCalledTimes(1);
expect(fn).toHaveBeenCalledWith("arg1", "arg2");
});
```
### jest.fn() Compatibility
```typescript
import { test, expect, jest } from "bun:test";
const fn = jest.fn(() => "value");
test("jest.fn works", () => {
const result = fn();
expect(result).toBe("value");
expect(fn).toHaveBeenCalled();
});
```
## Mock Return Values
```typescript
const fn = mock();
// Return value once
fn.mockReturnValueOnce("first");
fn.mockReturnValueOnce("second");
// Permanent return value
fn.mockReturnValue("default");
// Promise returns
fn.mockResolvedValue("resolved");
fn.mockResolvedValueOnce("once");
fn.mockRejectedValue(new Error("fail"));
fn.mockRejectedValueOnce(new Error("once"));
```
## Mock Implementations
```typescript
const fn = mock();
// Set implementation
fn.mockImplementation((x) => x * 2);
…Read the whole file at its exact version.
How to install
mdr add secondsky/claude-skills/bun-test-mocking@sha256:24f1bd841f59ed4dThe line at the top of this page pins the label v1.0.0, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_6uvpdbch5lg42zbh)
5 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 3 versions of this file, between Dec 29, 2025 and Apr 2, 2026, about one every 47 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| v1.0.0 latest | 2026-04-02 | 75421fa | 5,374 B | A | view · diff |
| v1.0.0 | 2026-04-02 | 89c5e89 | 5,361 B | A | view · diff |
| v1.0.0 | 2025-12-29 | 2cbc8ed | 5,347 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (5374 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
secondsky/claude-skills · 247 stars · license MIT · pushed 2026-10-31 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_6uvpdbch5lg42zbh GET https://markdownregistry.com/api/v1/resolve?ref=secondsky/claude-skills/bun-test-mocking GET https://markdownregistry.com/api/v1/blob/24f1bd841f59ed4d78b931e535cbf8e6b76bd8be67b5f40c3c79f938b6d24fee
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.