chore: type improvements

src/PHPStan/HigherOrderExpectationTypeExtension.php

@@ -0,0 +1,57 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\PHPStan;
+
+use Pest\Expectations\HigherOrderExpectation;
+use PhpParser\Node\Expr;
+use PhpParser\Node\Expr\PropertyFetch;
+use PhpParser\Node\Identifier;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\ReflectionProvider;
+use PHPStan\Type\ExpressionTypeResolverExtension;
+use PHPStan\Type\ObjectType;
+use PHPStan\Type\Type;
+
+/**
+ * Prevents native declared properties of HigherOrderExpectation (like $original,
+ * $expectation, $opposite, $shouldReset) from being incorrectly resolved as
+ * higher-order value property accesses by downstream ExpressionTypeResolverExtensions.
+ *
+ * This extension must be registered BEFORE the peststan HigherOrderExpectationTypeExtension.
+ *
+ * @internal
+ */
+final readonly class HigherOrderExpectationTypeExtension implements ExpressionTypeResolverExtension
+{
+    public function __construct(
+        private ReflectionProvider $reflectionProvider,
+    ) {}
+
+    public function getType(Expr $expr, Scope $scope): ?Type
+    {
+        if (! $expr instanceof PropertyFetch || ! $expr->name instanceof Identifier) {
+            return null;
+        }
+
+        $varType = $scope->getType($expr->var);
+
+        if (! (new ObjectType(HigherOrderExpectation::class))->isSuperTypeOf($varType)->yes()) {
+            return null;
+        }
+
+        if (! $this->reflectionProvider->hasClass(HigherOrderExpectation::class)) {
+            return null;
+        }
+
+        $propertyName = $expr->name->name;
+        $classReflection = $this->reflectionProvider->getClass(HigherOrderExpectation::class);
+
+        if (! $classReflection->hasNativeProperty($propertyName)) {
+            return null;
+        }
+
+        return $varType->getProperty($propertyName, $scope)->getReadableType();
+    }
+}