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Test Implement Constructor Validation

This skill automates the creation of constructor validation tests for Python service classes. It analyzes service __init__ methods to generate pytest test cases that verify required parameters raise ValueError when None, following the fail-fast principle.

Test Implement Constructor Validation auto-generates pytest tests that verify service constructors properly validate required parameters.

AI-generated summary based on this skill's SKILL.md

1 0 unlicensed, metadata onlyupdated by dawiddutoit

Decision gist · record as of 2026-01-26

Test Implement Constructor Validation auto-generates pytest tests that verify service constructors properly validate required parameters. This skill automates the creation of constructor validation tests for Python service classes. It analyzes service __init__ methods to generate pytest test cases that verify required parameters raise ValueError when None, following the fail-fast principle.

manual: git clone https://github.com/dawiddutoit/custom-claude → cp -r custom-claude ~/.claude/skills/test-implement-constructor-validation

Use it when

  • Test Implement Constructor Validation generates pytest test cases automatically by analyzing your service class __init__ methods.
  • Test Implement Constructor Validation generates pytest test cases tailored to your service classes.
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Install

dawiddutoit/custom-claude/test-implement-constructor-validation · repository language: Python

generated, unverified - the skill's exact subdirectory could not be determined; check the repository on GitHub

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Frequently asked questions

AI-generated answers based on this skill's SKILL.md and metadata

What does Test Implement Constructor Validation do?

Test Implement Constructor Validation automates the creation of constructor validation tests for Python service classes. It analyzes service __init__ methods to generate pytest test cases that verify required parameters raise ValueError when None, following the fail-fast principle.

How do I implement constructor validation in my code?

Test Implement Constructor Validation generates pytest test cases automatically by analyzing your service class __init__ methods. The skill creates tests that verify each required parameter raises ValueError when passed None, ensuring your constructors validate inputs before proceeding with initialization.

What constructor validation testing examples does this skill provide?

Test Implement Constructor Validation generates pytest test cases tailored to your service classes. Each example verifies that required constructor parameters properly raise ValueError when None is passed, demonstrating the fail-fast validation pattern for parameter checking.

What are constructor validation best practices?

Test Implement Constructor Validation follows best practices by enforcing fail-fast validation: required parameters must raise ValueError when None before any other initialization occurs. This prevents invalid state propagation and ensures your service classes catch configuration errors immediately at construction time.

How can I test constructor parameter validation?

Test Implement Constructor Validation creates pytest test cases that systematically validate each constructor parameter. The generated tests verify that passing None to required parameters triggers ValueError, confirming your validation logic works correctly and prevents invalid service instances from being created.

What constructor validation patterns does this skill use?

Test Implement Constructor Validation implements the fail-fast pattern: required parameters are validated in __init__ to raise ValueError when None, preventing invalid object construction. This pattern ensures service classes maintain invariants from instantiation and catches configuration errors at the earliest point.

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Tags
parameter-validationconstructor-testinginput-verificationobject-initializationvalidation-patternsdefensive-programmingtest-implementation