phpstan-pest

PHPStan extension that provides typed $this in Pest PHP test closures.

Solves the "undefined property" errors PHPStan reports when you assign dynamic properties to $this in beforeEach and use them in your tests.

Note: This extension uses some unstable PHPStan APIs and may require updates on minor PHPStan releases.

Requirements

• PHP 8.4+
• PHPStan 2.0+

Installation

composer require --dev imsuperlative/phpstan-pest

If you have phpstan/extension-installer, the extension is registered automatically. Otherwise, add it to your phpstan.neon:

includes:
    - vendor/imsuperlative/phpstan-pest/extension.neon

Configuration

parameters:
    PhpstanPest:
        testCaseClass: PHPUnit\Framework\TestCase  # Base test case class
        parseAssignments: true                     # $this->prop = expr inference
        parsePestPropertyTags: false               # @pest-property tags
        parsePhpDocProperties: false               # @property PHPDoc tags
        parseUses: true                            # Resolve uses()/pest()->extend() traits
        parseParentUses: true                      # Walk up for parent Pest.php files
        expectationPropertyAccess: true            # Higher-order property access on expect()
        expectationSequenceTypes: false            # Typed closures in ->sequence()
        expectationScopedTypes: false              # Typed closures in ->scoped()
        simplifyToBe: true                         # ->toBe(true/false) → ->toBeTrue/False()
        simplifyToBeNull: true                     # ->toBe(null) → ->toBeNull()
        simplifyToBeEmpty: true                    # ->toBe('')/->toBe([]) → ->toBeEmpty()
        simplifyToHaveCount: true                  # ->toHaveCount(0) → ->toBeEmpty()
        simplifyToHaveLength: true                 # ->toHaveLength(0) → ->toBeEmpty()

If your project extends the base TestCase (e.g. in Laravel with Testbench), point testCaseClass to your own class:

parameters:
    PhpstanPest:
        testCaseClass: Tests\TestCase

Features

Typed dynamic properties

Infers types from $this->prop = expr assignments in beforeEach using PHPStan's own type resolver:

beforeEach(function () {
    $this->user = User::factory()->create();
});

it('has a name', function () {
    // PHPStan knows $this->user is User
    expect($this->user->name)->toBeString();
});

Alternatively, declare types via @pest-property or @property PHPDoc tags.

Full documentation

Uses & trait resolution

Resolves trait methods from uses() and pest()->extend() calls, including parent Pest.php files with ->in() scoping:

// tests/Pest.php
pest()->extends(HasGreeting::class)->in('Inherited');

// tests/Inherited/FooTest.php
it('can call trait methods', function () {
    expect($this->greet('world'))->toBe('Hello, world!');
});

Full documentation

Expectations

Higher-order method proxying, property access on expect(), union type narrowing, and custom expectations:

it('proxies and accesses properties', function () {
    expect($user)
        ->name->toBe('Test');

    expect(collect([1, 2, 3]))->first()->toBe(1);
});

// Union types are automatically narrowed to members that have the accessed property/method
it('narrows union types', function () {
    /** @var Order|Order[]|null $order */
    $order = Order::factory()->create();

    expect($order)
        ->id->toBeInt()          // narrows to Order (only Order has ->id)
        ->status->toBeString();
});

Full documentation

Rules

Assertion simplification

Suggests simpler Pest assertion methods when a more expressive alternative exists:

Before	After
->toBe(true)	->toBeTrue()
->toBe(false)	->toBeFalse()
->toBe(null)	->toBeNull()
->toBe('') / ->toBe([])	->toBeEmpty()
->toHaveCount(0)	->toBeEmpty()
->toHaveLength(0)	->toBeEmpty()

Full documentation

Supported Pest functions

it, test, describe, beforeEach, afterEach (both short and Pest\ namespaced forms).

PHPStan API Compatibility

This extension relies on PHPStan APIs not covered by the backward compatibility promise. These are baselined and may require updates on minor PHPStan releases.

API	Why
WrappedExtendedPropertyReflection	Wraps PropertyReflection into ExtendedPropertyReflection for property access on custom types
UnresolvedPropertyPrototypeReflection	Required by ObjectType::getUnresolvedPropertyPrototype()
UnresolvedMethodPrototypeReflection	Required for trait method resolution on custom types
ExtendedMethodReflection	Required for exposing trait methods as public
PhpDocStringResolver::resolve()	Parses PHPDoc blocks for @pest-property and @property tags

License

MIT