testing.md

Testing

ConfigLoader uses PHPUnit for deterministic unit and integration tests.

Running Tests

vendor/bin/phpunit

Or through Composer:

composer test

What Is Tested

The current test suite covers:

• YAML parsing
• JSON parsing
• YAML extension path and internal fallback path
• interpolation behavior
• layered merge behavior
• missing file failures
• invalid syntax failures
• missing environment variable failures
• format enforcement
• JSON ext-json availability checks

Why These Tests Matter

• parsing tests guard the strict format behavior
• merge tests preserve deterministic override rules
• interpolation tests preserve explicit environment handling
• integration tests verify the full resolve -> parse -> merge -> interpolate -> return pipeline

Test Design Constraints

• tests must be deterministic
• no external services
• no framework dependencies
• environment-dependent behavior should be simulated through explicit test doubles when needed

Related Documents

• Pipeline
• Exceptions
• Extension guidance