chrysalis-test 0.1.2

A metamorphic testing framework for Python

Chrysalis

A metamorphic testing framework that utilizes metamorphic relations.

What is Metamorphic Testing?

Metamorphic testing is a software testing technique that focuses on relations between multiple executions of a program. Instead of checking if a program produces the "correct" output for a given input (which may be unknown) metamorphic testing verifies that certain relationships hold between inputs and their corresponding outputs.

Core Concepts

System Under Test (SUT) - The function or system to test.

Transformations - Functions that modify the input data while preserving certain properties.

Invariants - Predicates that define relationships between outputs.

Metamorphic Relations - The combination of a transformation and invariant that defines a testable property of a system.

Installation

pip install chrysalis-test

Usage

Registering Relations

Use chry.register() to register metamorphic relations by combining transformations and invariants:

import chrysalis as chry

chry.register(
    transformation=transformation_function,
    invariant=chry.invariants.equals
)

Running Tests

Use chry.run() to execute metamorphic testing on your system under test:

results = chry.run(
    sut=sut_function,
    input_data=test_data,
    chain_length=10,
    num_chains=20
)

Official Documentation

Chrysalis - A metamorphic testing framework that utilizes metamorphic relations to detect bugs.

Development

For development, use the following commands:

• Format and check code: ./scripts/format_and_check.sh
• Run unit tests: uv run pytest
• Run integration test: python3 -m tests_integration.sql
• Build docs: ./scripts/build_docs.sh