Narrow type of reflection get*Type() after calling has*Type()

Author: paulbalandan

stubs/ReflectionFunctionAbstract.stub

@@ -14,4 +14,19 @@ abstract class ReflectionFunctionAbstract
     public function getAttributes(?string $name = null, int $flags = 0)
     {
     }
+
+	/**
+	 * @phpstan-assert-if-true !null $this->getReturnType()
+	 */
+	public function hasReturnType(): bool
+	{
+	}
+
+	/**
+	 * @phpstan-assert-if-true !null $this->getTentativeReturnType()
+	 */
+	public function hasTentativeReturnType(): bool
+	{
+	}
+
 }

stubs/ReflectionParameter.stub

@@ -8,4 +8,12 @@ class ReflectionParameter
     public function getAttributes(?string $name = null, int $flags = 0)
     {
     }
+
+	/**
+	 * @phpstan-assert-if-true !null $this->getType()
+	 */
+	public function hasType(): bool
+	{
+	}
+
 }

stubs/ReflectionProperty.stub

@@ -2,10 +2,19 @@
 
 class ReflectionProperty
 {
+
     /**
      * @return list<ReflectionAttribute<object>>
      */
     public function getAttributes(?string $name = null, int $flags = 0)
     {
     }
+
+	/**
+	 * @phpstan-assert-if-true !null $this->getType()
+	 */
+	public function hasType(): bool
+	{
+	}
+
 }

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -77,6 +77,12 @@ private static function findTestFiles(): iterable
 			yield __DIR__ . '/data/explode-php80.php';
 		}
 
+		if (PHP_VERSION_ID >= 80000) {
+			yield __DIR__ . '/data/reflection-type-php8.php';
+		} else {
+			yield __DIR__ . '/data/reflection-type-php7.php';
+		}
+
 		if (PHP_VERSION_ID >= 80000) {
 			yield __DIR__ . '/../Reflection/data/unionTypes.php';
 			yield __DIR__ . '/../Reflection/data/mixedType.php';

tests/PHPStan/Analyser/data/reflection-type-php7.php

@@ -0,0 +1,33 @@
+<?php
+
+namespace ReflectionTypeTestPhp7;
+
+use function PHPStan\Testing\assertType;
+
+function test(
+	\ReflectionProperty $reflectionProperty,
+	\ReflectionFunctionAbstract $reflectionFunctionAbstract,
+	\ReflectionParameter $reflectionParameter
+){
+	assertType('ReflectionType|null', $reflectionProperty->getType());
+	assertType('ReflectionType|null', $reflectionFunctionAbstract->getReturnType());
+	assertType('ReflectionType|null', $reflectionParameter->getType());
+
+	if ($reflectionProperty->hasType()) {
+		assertType('ReflectionType', $reflectionProperty->getType());
+	} else {
+		assertType('null', $reflectionProperty->getType());
+	}
+
+	if ($reflectionFunctionAbstract->hasReturnType()) {
+		assertType('ReflectionType', $reflectionFunctionAbstract->getReturnType());
+	} else {
+		assertType('null', $reflectionFunctionAbstract->getReturnType());
+	}
+
+	if ($reflectionParameter->hasType()) {
+		assertType('ReflectionType', $reflectionParameter->getType());
+	} else {
+		assertType('null', $reflectionParameter->getType());
+	}
+}

tests/PHPStan/Analyser/data/reflection-type-php8.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace ReflectionTypeTestPhp8;
+
+use function PHPStan\Testing\assertType;
+
+function test(
+	\ReflectionProperty $reflectionProperty,
+	\ReflectionFunctionAbstract $reflectionFunctionAbstract,
+	\ReflectionParameter $reflectionParameter
+){
+	assertType('ReflectionType|null', $reflectionProperty->getType());
+	assertType('ReflectionType|null', $reflectionFunctionAbstract->getReturnType());
+	assertType('ReflectionType|null', $reflectionFunctionAbstract->getTentativeReturnType());
+	assertType('ReflectionType|null', $reflectionParameter->getType());
+
+	if ($reflectionProperty->hasType()) {
+		assertType('ReflectionType', $reflectionProperty->getType());
+	} else {
+		assertType('null', $reflectionProperty->getType());
+	}
+
+	if ($reflectionFunctionAbstract->hasReturnType()) {
+		assertType('ReflectionType', $reflectionFunctionAbstract->getReturnType());
+	} else {
+		assertType('null', $reflectionFunctionAbstract->getReturnType());
+	}
+
+	if ($reflectionFunctionAbstract->hasTentativeReturnType()) {
+		assertType('ReflectionType', $reflectionFunctionAbstract->getTentativeReturnType());
+	} else {
+		assertType('null', $reflectionFunctionAbstract->getTentativeReturnType());
+	}
+
+	if ($reflectionParameter->hasType()) {
+		assertType('ReflectionType', $reflectionParameter->getType());
+	} else {
+		assertType('null', $reflectionParameter->getType());
+	}
+}