feat: type narrowing for ReflectionClass::

Author: SamMousa

stubs/ReflectionClass.stub

@@ -49,12 +49,14 @@ class ReflectionClass
     {
     }
 
-    /**
-     * @phpstan-assert-if-true class-string<\UnitEnum> $this->name
-     * @phpstan-assert-if-true ReflectionClass<\UnitEnum> $this
-	 * @phpstan-assert-if-false !class-string<\UnitEnum> $this->name
-     */
-    public function isEnum(): bool
-    {
-    }
+	/**
+	 * @phpstan-assert-if-true class-string<\UnitEnum> $this->name
+	 * @phpstan-assert-if-true class-string<\UnitEnum> $this->getName()
+	 * @phpstan-assert-if-true ReflectionClass<UnitEnum> $this
+	 * @return (T is \UnitEnum ? true: false)
+	 */
+	public function isEnum(): bool
+	{
+	}
+
 }

stubs/ReflectionClassWithLazyObjects.stub

@@ -110,4 +110,13 @@ class ReflectionClass
 	public function isUninitializedLazyObject(object $object): bool
 	{
 	}
+
+	/**
+	 * @phpstan-assert-if-true class-string<\UnitEnum> $this->name
+	 * @phpstan-assert-if-true class-string<\UnitEnum> $this->getName()
+	 * @return (T is \UnitEnum ? true: false)
+	 */
+	public function isEnum(): bool
+	{
+	}
 }

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -238,7 +238,6 @@ private static function findTestFiles(): iterable
 		yield __DIR__ . '/../Rules/Methods/data/bug-4801.php';
 		yield __DIR__ . '/../Rules/Arrays/data/narrow-superglobal.php';
 		yield __DIR__ . '/../Rules/Methods/data/bug-12927.php';
-		yield __DIR__ . '/data/reflectionclass-isEnum.php';
 	}
 
 	/**

tests/PHPStan/Analyser/data/reflectionclass-isEnum.php

@@ -0,0 +1,36 @@
+<?php // lint >= 8.1
+
+namespace ReflectionClassIsEnum;
+
+use ReflectionClass;
+use function PHPStan\Testing\assertType;
+
+/**
+ * @param class-string $class
+ */
+function testNarrowClassAfterIsEnum(string $class): void {
+	$r = new ReflectionClass($class);
+	if ($r->isEnum()) {
+		assertType('class-string<UnitEnum>', $r->name);
+		assertType('class-string<UnitEnum>', $r->getName());
+
+
+		// Todo:
+		//assertType('ReflectionClass<UnitEnum>', $r);
+
+	}
+
+
+
+}
+
+function testTemplateAssertions(): void  {
+	$enumR = new ReflectionClass(Foo::class);
+	assertType('ReflectionClass<ReflectionClassIsEnum\\Foo>', $enumR);
+	assertType('true', $enumR->isEnum());
+}
+
+
+enum Foo {
+	case Bar;
+}