phpstan-pest-this

PHPStan extensions that infer Pest closure $this type from configurable test-path mappings.

Why

Pest binds test closures at runtime, while PHPStan analyzes code statically. Without extra help, closure $this is commonly inferred as PHPUnit\Framework\TestCase, which can produce false positives in Pest suites.

Installation

composer require --dev odinns/phpstan-pest-this

Quick setup

Add the extension to your PHPStan config:

includes:
    - vendor/odinns/phpstan-pest-this/extension.neon

Configure how file paths map to Pest base test case classes:

parameters:
    pestClosureThisTypeMap:
        -
            pathContains: '/tests/Feature/'
            class: Tests\Feature\TestCase
        -
            pathContains: '/tests/Unit/'
            class: Tests\Unit\TestCase

pathContains is a substring match against the analyzed file path. The first matching mapping wins.

Supported Pest calls

• Function calls: it(...), test(...), beforeEach(...), afterEach(...)
• Fluent hooks: uses(...)->beforeEach(...), uses(...)->afterEach(...)

Optional: Generate a PHPStan proxy test case

If your base test case has protected assertion helpers, PHPStan may flag visibility errors from Pest closures. Use the included generator to create a static-analysis-only proxy class with public wrappers.

After installation:

vendor/bin/generate-pest-proxy.php \
  --source="Tests\\Feature\\TestCase" \
  --target="tests/PHPStan/PestFeatureTestCase.php" \
  --namespace="Tests\\PHPStan" \
  --class="PestFeatureTestCase"

While developing this package locally:

php tools/generate-pest-proxy.php \
  --source="Tests\\Feature\\TestCase" \
  --target="tests/PHPStan/PestFeatureTestCase.php" \
  --namespace="Tests\\PHPStan" \
  --class="PestFeatureTestCase"

Then map the relevant directory to the generated proxy:

parameters:
    pestClosureThisTypeMap:
        -
            pathContains: '/tests/Feature/'
            class: Tests\PHPStan\PestFeatureTestCase

This proxy only affects static analysis. It does not change Pest runtime behavior.

Limitations

• The extension resolves closure $this type only.
• It does not infer dynamic properties automatically; declare those on your test case/traits.
• Mapping is path-substring based, so very broad patterns can match unintentionally.

Troubleshooting

• No effect in analysis: confirm extension.neon is included in your PHPStan config.
• Wrong inferred class: ensure mapping order is specific to broad (first match wins).
• Generator not found: use vendor/bin/generate-pest-proxy.php after install or php tools/generate-pest-proxy.php in this repository.

License

MIT