Agent skill

Mocking Test Generator

Generate unit tests with proper mocking for Python (unittest.mock/pytest) or Java (Mockito/JUnit) code.

Apache-2.0Auto-check passedTesting & QA

Install Mocking Test Generator

skills CLI

$ npx skills add ArabelaTso/Skills-4-SE --skill mocking-test-generator -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install ArabelaTso/Skills-4-SE mocking-test-generator --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/ArabelaTso/Skills-4-SE.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/mocking-test-generator .claude/skills/mocking-test-generator && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Paste into Claude Code

Install the "mocking-test-generator" agent skill from https://github.com/ArabelaTso/Skills-4-SE/tree/main/skills/mocking-test-generator into .claude/skills/mocking-test-generator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "mocking-test-generator", then confirm the skill loads.

Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

$skill-installer

$skill-installer install https://github.com/ArabelaTso/Skills-4-SE/tree/main/skills/mocking-test-generator

Type this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.

skills CLI

$ npx skills add ArabelaTso/Skills-4-SE --skill mocking-test-generator -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install ArabelaTso/Skills-4-SE mocking-test-generator --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/ArabelaTso/Skills-4-SE.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/mocking-test-generator .agents/skills/mocking-test-generator && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "mocking-test-generator" agent skill from https://github.com/ArabelaTso/Skills-4-SE/tree/main/skills/mocking-test-generator into .agents/skills/mocking-test-generator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "mocking-test-generator", then confirm the skill loads.

Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add ArabelaTso/Skills-4-SE --skill mocking-test-generator -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install ArabelaTso/Skills-4-SE mocking-test-generator --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/ArabelaTso/Skills-4-SE.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/mocking-test-generator .cursor/skills/mocking-test-generator && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "mocking-test-generator" agent skill from https://github.com/ArabelaTso/Skills-4-SE/tree/main/skills/mocking-test-generator into .cursor/skills/mocking-test-generator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "mocking-test-generator", then confirm the skill loads.

Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

gemini skills install

$ gemini skills install https://github.com/ArabelaTso/Skills-4-SE.git --path skills/mocking-test-generator

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add ArabelaTso/Skills-4-SE --skill mocking-test-generator -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install ArabelaTso/Skills-4-SE mocking-test-generator --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/ArabelaTso/Skills-4-SE.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/mocking-test-generator .gemini/skills/mocking-test-generator && rm -rf skills-src

Use ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.

Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/

Paste into Gemini CLI

Install the "mocking-test-generator" agent skill from https://github.com/ArabelaTso/Skills-4-SE/tree/main/skills/mocking-test-generator into .gemini/skills/mocking-test-generator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "mocking-test-generator", then confirm the skill loads.

Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

GitHub CLI

$ gh skill install ArabelaTso/Skills-4-SE mocking-test-generator

Installs for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).

skills CLI

$ npx skills add ArabelaTso/Skills-4-SE --skill mocking-test-generator -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/ArabelaTso/Skills-4-SE.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/mocking-test-generator .github/skills/mocking-test-generator && rm -rf skills-src

Use ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.

GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/

Paste into GitHub Copilot

Install the "mocking-test-generator" agent skill from https://github.com/ArabelaTso/Skills-4-SE/tree/main/skills/mocking-test-generator into .github/skills/mocking-test-generator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "mocking-test-generator", then confirm the skill loads.

GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add ArabelaTso/Skills-4-SE --skill mocking-test-generator -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install ArabelaTso/Skills-4-SE mocking-test-generator --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/ArabelaTso/Skills-4-SE.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/mocking-test-generator .opencode/skills/mocking-test-generator && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "mocking-test-generator" agent skill from https://github.com/ArabelaTso/Skills-4-SE/tree/main/skills/mocking-test-generator into .opencode/skills/mocking-test-generator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "mocking-test-generator", then confirm the skill loads.

OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

Facts

Skill name: mocking-test-generator
GitHub stars: 253
Token cost: ~1.6k tokens
SKILL.md length: 583 words
Files: 3 (incl. references)
Skills in repo: 151
Repo updated: Aug 21, 2026
First seen: Oct 7, 2026
Licence: Apache-2.0

At a glance

Generate unit tests with proper mocking for Python (unittest.mock/pytest) or Java (Mockito/JUnit) code.

Works in 5 steps: Analyze the Code → Select Framework → Generate Mocks → …
Users request test generation
SKILL.md covers Workflow, Step 1: Analyze the Code, Step 2: Select Framework and Step 3: Generate Mocks, plus 6 more sections
Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

Mocking Test Generator is an agent skill from ArabelaTso/Skills-4-SE. Generate unit tests with proper mocking for Python (unittest.mock/pytest) or Java (Mockito/JUnit) code. Use when users request test generation, unit tests with mocks, or testing code that has external dependencies like database calls, API requests, file I/O, or network operations. Automatically identifies dependencies to mock and creates executable, maintainable test code.

Its SKILL.md is about 1.6k tokens, which your agent loads only when the skill is triggered. The skill folder holds 3 other files, including reference files (for example `references/java_patterns.md` and `references/python_patterns.md`).

It sits in Testing & QA, covering Unit testing and Test generation. It works with Java, Python, pytest and JUnit. The repository describes itself as: A curated list of 180+ useful Claude Skills for Software Engineering and resources for customizing AI for SE workflows. The licence is Apache-2.0.

When your agent uses it

Users request test generation
Unit tests with mocks
Testing code that has external dependencies like database calls
Network operations

Example prompts

“/mocking-test-generator”

Requirements

Python 3

Workflow steps

5 steps, taken from the step headings in SKILL.md.

Analyze the Code
Select Framework
Generate Mocks
Write Tests
Add Documentation

What it can do on your machine

Read from SKILL.md and the folder at commit 4f38503. It shows what the files ask for, not the result of running them.

Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md (its code samples are python and java).
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Mocking Test Generator loads about 1.6k tokens when it runs, and up to ~3.9k if it reads all its reference files. Until then it costs about 100 tokens; SKILL.md has 583 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~100
When it runs · the whole SKILL.md, loaded when a task matches: ~1.6k
With references · SKILL.md plus every file in references/, read only if the agent opens them: ~3.9k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from ArabelaTso/Skills-4-SE at commit 4f38503, republished under its Apache-2.0 licence (© ArabelaTso). 583 words, ~1,574 tokens.

Download SKILL.mdSave it as .claude/skills/mocking-test-generator/SKILL.md (or your agent's skills folder). This skill also uses 2 other files; get the full folder from GitHub.

name: mocking-test-generator
description: Generate unit tests with proper mocking for Python (unittest.mock/pytest) or Java (Mockito/JUnit) code. Use when users request test generation, unit tests with mocks, or testing code that has external dependencies like database calls, API requests, file I/O, or network operations. Automatically identifies dependencies to mock and creates executable, maintainable test code.

Mocking Test Generator

Generate unit tests with proper mocking of external dependencies for Python and Java code.

Workflow

Analyze the code - Identify external dependencies, side effects, and testable units
Select framework - Determine Python (unittest.mock/pytest) or Java (Mockito/JUnit)
Generate mocks - Create mock objects for external dependencies
Write tests - Generate executable test code with assertions
Add documentation - Include clear comments explaining mocks and test logic

Step 1: Analyze the Code

Read the target code to identify:

External dependencies: API clients, database connections, third-party libraries
I/O operations: File reads/writes, network requests, system calls
Side effects: Email sending, logging, state modifications
Testable units: Functions, methods, or classes to test in isolation

Ask clarifying questions if:

Multiple functions/classes exist (which to test?)
Testing scope is unclear (unit vs integration?)
Mock behavior needs specification (return values, exceptions?)

Step 2: Select Framework

Python: Use unittest.mock with pytest or unittest

Prefer @patch decorator for external calls
Use Mock() objects for complex dependencies
Apply pytest.fixture for reusable mocks

Java: Use Mockito with JUnit 5

Use @Mock annotation for dependencies
Apply @ExtendWith(MockitoExtension.class) to test class
Use when().thenReturn() for stubbing

Step 3: Generate Mocks

Identify what to mock:

Always mock:

External API calls (HTTP requests, REST clients)
Database connections and queries
File system operations
Network I/O
Time/date functions
Random number generators
Environment variables

Never mock (unless explicitly requested):

Internal business logic
Pure functions
Data structures
Simple utilities

For common patterns, reference:

Python: See references/python_patterns.md
Java: See references/java_patterns.md

Step 4: Write Tests

Generate test code that:

Imports - Include necessary testing and mocking libraries
Setup - Initialize mocks and test fixtures
Execution - Call the function/method under test
Assertions - Verify expected behavior and outputs
Verification - Confirm mocks were called correctly

Test structure:

python

# Python example
from unittest.mock import patch, Mock
import pytest

@patch('module.external_dependency')
def test_function_name(mock_dependency):
    # Arrange: Setup mock behavior
    mock_dependency.return_value = expected_value

    # Act: Execute function under test
    result = function_under_test(input_data)

    # Assert: Verify results
    assert result == expected_output
    mock_dependency.assert_called_once_with(expected_args)

java

// Java example
@ExtendWith(MockitoExtension.class)
class ServiceTest {
    @Mock
    private ExternalDependency dependency;

    @Test
    void testMethodName() {
        // Arrange: Setup mock behavior
        when(dependency.method()).thenReturn(expectedValue);

        // Act: Execute method under test
        Service service = new Service(dependency);
        String result = service.methodUnderTest();

        // Assert: Verify results
        assertEquals(expectedOutput, result);
        verify(dependency).method();
    }
}

Include:

Multiple test cases for different scenarios (happy path, edge cases, errors)
Descriptive test names that explain what is being tested
Setup/teardown if needed for test isolation

Step 5: Add Documentation

Include comments that explain:

What external dependency is being mocked and why
What behavior the mock simulates
What the test verifies

Keep comments concise and focused on non-obvious aspects.

Show full SKILL.md (236 more words)Show less

Output Format

Provide:

Complete test file - Fully executable with all imports
Test class/module - Properly structured for the framework
Multiple test methods - Cover main scenarios
Clear naming - Descriptive test and variable names

Do not:

Modify the original code under test
Mock internal logic unless explicitly requested
Generate incomplete or pseudo-code tests

Example Usage

User request: "Generate unit tests for this Python function that calls an external API"

Response:

Read the function code
Identify the API call to mock
Generate pytest test file with @patch decorator
Include tests for success case, error handling, and edge cases
Add comments explaining the mock setup

Framework-Specific Notes

Python (pytest):

Use @pytest.fixture for reusable mock setups
Apply @patch as decorator or context manager
Use mock_open for file operations
Apply @patch.dict for environment variables

Python (unittest):

Use unittest.TestCase base class
Apply @patch decorator or patch() context manager
Use setUp() and tearDown() methods
Call self.assert* methods

Java (Mockito + JUnit 5):

Use @ExtendWith(MockitoExtension.class) on test class
Apply @Mock for dependencies
Use @BeforeEach for setup, @AfterEach for teardown
Apply ArgumentCaptor to verify complex arguments
Use MockedStatic for static method mocking (Mockito 3.4+)

Common Patterns

Reference files contain detailed examples for:

Python (references/python_patterns.md):

External API calls
Database operations
File system operations
Environment variables
Time-dependent code
Exception handling

Java (references/java_patterns.md):

External API calls
Database operations
File system operations
Void methods
Exception handling
Argument captors
Static method mocking
Constructor mocking

Files

SKILL.md and 2 other files (references) in skills/mocking-test-generator of ArabelaTso/Skills-4-SE.

SKILL.md
references/java_patterns.md
references/python_patterns.md

Open the folder on GitHubat commit 4f38503

Compare with similar skills

Mocking Test Generator next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Mocking Test Generator compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Mocking Test Generator this skillArabelaTso/Skills-4-SE	253	—	~1.6k	Automated safety check: Pass	Apache-2.0	1 mo ago
TDD GuideLeoYeAI/openclaw-master-skills	2.2k	—	~1.4k	Automated safety check: Pass	MIT	2 mo ago
Test Analysis Extensionsmicrosoft/testfx	1k	2 repos	~1.1k	Automated safety check: Pass	MIT	today
TDD Guidealirezarezvani/claude-skills	28k	—	~3.4k	Automated safety check: Pass	MIT	1 mo ago
TDD GuideaAAaqwq/AGI-Super-Team	105	2 repos	~1.1k	Automated safety check: Pass	MIT	10 days ago
Adk Verify Snippetsgoogle/adk-python	22k	—	~1.4k	Automated safety check: Pass	Apache-2.0	today

Similar skills

TDD Guide
LeoYeAI/openclaw-master-skills
Test-driven development skill for writing unit tests, generating test fixtures and mocks, analyzing coverage gaps, and guiding red-green-refactor workflows across Jest, Pytest, JUnit, Vitest, and…
2.2k GitHub stars~1.4k tokensUpdated 2 mo ago
Testing & QAAuto-check passed
Test Analysis Extensions
microsoft/testfx
Official
Provides file paths to language-specific reference files for the test ANALYSIS skills (assertion-quality, test-anti-patterns, test-gap-analysis, test-smell-detection, test-tagging).
1k GitHub starsUsed in 2 repos~1.1k tokens
Testing & QAAuto-check passed
TDD Guide
alirezarezvani/claude-skills
Test-driven development skill for writing unit tests, generating test fixtures and mocks, analyzing coverage gaps, and guiding red-green-refactor workflows across Jest, Pytest, JUnit, Vitest, and…
28k GitHub stars~3.4k tokensUpdated 1 mo ago
Testing & QAAuto-check passed
TDD Guide
aAAaqwq/AGI-Super-Team
Test-driven development workflow with test generation, coverage analysis, and multi-framework support
105 GitHub starsUsed in 2 repos~1.1k tokens
Testing & QAAuto-check passed
Adk Verify Snippets
google/adk-python
Official
Checks that every Python code block in a Markdown file actually compiles and runs, by extracting each block to a temporary file, executing it in an isolated subprocess, and writing a pass/fail…
22k GitHub stars~1.4k tokensUpdated today
Testing & QAAuto-check passed
Hermetic Python Unit Tests
dimensionalOS/dimos
Rules for writing, fixing and reviewing pytest unit tests that are hermetic: behavior-focused, deterministic, isolated and cheap to run.
4.6k GitHub stars~1.4k tokensUpdated yesterday
Testing & QAAuto-check passed

Questions about Mocking Test Generator

What does Mocking Test Generator do?

Generate unit tests with proper mocking for Python (unittest.mock/pytest) or Java (Mockito/JUnit) code. Mocking Test Generator is an agent skill from ArabelaTso/Skills-4-SE.mock/pytest) or Java (Mockito/JUnit) code.

When should I use Mocking Test Generator?

Mocking Test Generator fits situations like: users request test generation; unit tests with mocks; testing code that has external dependencies like database calls; network operations.

How do I install Mocking Test Generator in Claude Code?

Run `npx skills add ArabelaTso/Skills-4-SE --skill mocking-test-generator -a claude-code`. Or copy the skill folder (skills/mocking-test-generator in ArabelaTso/Skills-4-SE) into .claude/skills/mocking-test-generator in your project. Claude Code loads it when a task matches its description.

How do I install Mocking Test Generator in Codex?

Run `npx skills add ArabelaTso/Skills-4-SE --skill mocking-test-generator -a codex`. Or copy the skill folder (skills/mocking-test-generator in ArabelaTso/Skills-4-SE) into .agents/skills/mocking-test-generator in your project. Codex loads it when a task matches its description.

Can I use Mocking Test Generator in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add ArabelaTso/Skills-4-SE --skill mocking-test-generator -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/mocking-test-generator, .gemini/skills/mocking-test-generator, .github/skills/mocking-test-generator and .opencode/skills/mocking-test-generator in your project.

What does Mocking Test Generator need to run?

SKILL.md names no scripts, command-line tools or credentials: Mocking Test Generator is instructions for the agent only. Our summary lists: Python 3.

Does Mocking Test Generator access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Mocking Test Generator safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Mocking Test Generator use?

Mocking Test Generator is published under the Apache-2.0 licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Mocking Test Generator use?

About 1.6k tokens (SKILL.md is roughly 6.3k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 2.4k tokens, read only when the agent opens those files.

What are the alternatives to Mocking Test Generator?

Skills that share tags, products or a category with Mocking Test Generator: TDD Guide (LeoYeAI/openclaw-master-skills, 2.2k stars), Test Analysis Extensions (microsoft/testfx, 1k stars), TDD Guide (alirezarezvani/claude-skills, 28k stars) and TDD Guide (aAAaqwq/AGI-Super-Team, 105 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Mocking Test Generator?

ArabelaTso (a GitHub user) maintains it in ArabelaTso/Skills-4-SE, which has 253 GitHub stars. The repository holds 151 skills in this directory. The repository was last updated on August 21, 2026.

Source: ArabelaTso/Skills-4-SE on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Install Mocking Test Generator

Facts

At a glance

What it does

When your agent uses it

Example prompts

Requirements

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Mocking Test Generator

Workflow

Step 1: Analyze the Code

Step 2: Select Framework

Step 3: Generate Mocks

Step 4: Write Tests

Step 5: Add Documentation

Output Format

Example Usage

Framework-Specific Notes

Common Patterns

Files

Compare with similar skills

Similar skills

More from ArabelaTso/Skills-4-SE

Related

Questions about Mocking Test Generator