Do I need to install specific tools for Level 1 tests?

Level 1 tests rely only on standard developer environment tools like Node.js, npm, git, and Unix shell utilities, ensuring they are fast and portable.

Why does this skill discourage mocking?

Mocking is often a sign of poor code design and tests implementation details rather than outcomes. This skill promotes dependency injection to create more resilient, reality-based tests.

When should I move from Unit to Integration tests?

Escalate to Level 2 (Integration) only when you need to verify that your code works correctly with real local binaries or project-specific tools that Level 1 cannot simulate.

What is the 'Progress vs Regression' test rule?

Progress tests live in the specs folder and can be 'Red' during development. Regression tests in the 'test/' directory must always be 'Green' to ensure the code is always deployable.

TypeScript Testing Methodology

Name: TypeScript Testing Methodology
Author: simonheimlicher

bysimonheimlicher

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Security & Testing

Implements a high-confidence, three-tiered testing framework for TypeScript using dependency injection and behavior-driven patterns.

This skill provides a structured methodology for testing TypeScript applications across three specific levels: Unit (Level 1), Integration (Level 2), and E2E (Level 3). It moves away from fragile mocking frameworks in favor of dependency injection and 'Reality as the Oracle,' ensuring tests verify what the system does rather than how it is implemented. By segregating 'Progress tests' for TDD from 'Regression tests' for CI stability, it allows developers to maintain a green deployment gate while iterating rapidly on new features.

Key Features

01Dependency injection patterns to eliminate fragile module mocking

02Segregated Progress vs. Regression test workflow for CI stability

031 GitHub stars

04Three-tiered testing architecture (Unit, Integration, E2E)

05Standardized Vitest configuration and type-safe test factories

06Behavior-focused verification strategies

Use Cases

01Implementing TDD for new TypeScript features without breaking CI pipelines

02Graduating unit tests into full-scale E2E workflows as feature confidence grows

03Refactoring legacy TypeScript code by replacing mocks with real dependencies

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add simonheimlicher/spx-claude testing-typescript

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