Resolve static in assert phpdoc

src/Reflection/Dummy/ChangedTypeMethodReflection.php

@@ -27,6 +27,7 @@ public function __construct(
 		private ?array $namedArgumentsVariants,
 		private ?Type $selfOutType,
 		private ?Type $throwType,
+		private Assertions $assertions,
 	)
 	{
 	}
@@ -133,7 +134,7 @@ public function hasSideEffects(): TrinaryLogic
 
 	public function getAsserts(): Assertions
 	{
-		return $this->reflection->getAsserts();
+		return $this->assertions;
 	}
 
 	public function acceptsNamedArguments(): TrinaryLogic

src/Reflection/Type/CallbackUnresolvedMethodPrototypeReflection.php

@@ -137,6 +137,7 @@ private function transformMethodWithStaticType(ClassReflection $declaringClass,
 			$namedArgumentVariants,
 			$selfOutType,
 			$throwType,
+			$method->getAsserts()->mapTypes($this->transformStaticTypeCallback),
 		);
 	}
 

src/Reflection/Type/CalledOnTypeUnresolvedMethodPrototypeReflection.php

@@ -132,6 +132,7 @@ private function transformMethodWithStaticType(ClassReflection $declaringClass,
 			$namedArgumentsVariants,
 			$selfOutType,
 			$throwType,
+			$method->getAsserts()->mapTypes(fn (Type $type): Type => $this->transformStaticType($type)),
 		);
 	}
 

tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php

@@ -3608,6 +3608,16 @@ public function testBug9141(): void
 		$this->analyse([__DIR__ . '/data/bug-9141.php'], []);
 	}
 
+	public function testBug12548(): void
+	{
+		$this->checkThisOnly = false;
+		$this->checkNullables = true;
+		$this->checkUnionTypes = true;
+		$this->checkExplicitMixed = true;
+
+		$this->analyse([__DIR__ . '/data/bug-12548.php'], []);
+	}
+
 	public function testBug3589(): void
 	{
 		$this->checkThisOnly = false;

tests/PHPStan/Rules/Methods/data/bug-12548.php

@@ -0,0 +1,86 @@
+<?php declare(strict_types = 1);
+
+namespace Bug12548;
+
+class BaseSat extends \stdClass
+{
+	/**
+	 * @template T of object
+	 *
+	 * @param T $object
+	 *
+	 * @phpstan-assert-if-true =static $object
+	 */
+	public static function assertInstanceOf(object $object): bool
+	{
+		return $object instanceof static;
+	}
+
+	/**
+	 * @template T of object
+	 *
+	 * @param T $object
+	 *
+	 * @return (T is static ? T : static)
+	 *
+	 * @phpstan-assert static $object
+	 */
+	public static function assertInstanceOf2(object $object)
+	{
+		if (!$object instanceof static) {
+			throw new \Error('Object is not an instance of static class');
+		}
+
+		return $object;
+	}
+}
+
+class StdSat extends BaseSat
+{
+	public function foo(): void {}
+
+	/**
+	 * @template T of object
+	 *
+	 * @param T $object
+	 *
+	 * @return (T is static ? T : static)
+	 *
+	 * @phpstan-assert static $object
+	 */
+	public static function assertInstanceOf3(object $object)
+	{
+		if (!$object instanceof static) {
+			throw new \Error('Object is not an instance of static class');
+		}
+
+		return $object;
+	}
+}
+
+class TestCase
+{
+	private function createStdSat(): \stdClass
+	{
+		return new StdSat();
+	}
+
+	public function testAssertInstanceOf(): void
+	{
+		$o = $this->createStdSat();
+		$o->foo(); // @phpstan-ignore method.nonObject (EXPECTED)
+
+		$o = $this->createStdSat();
+		if (StdSat::assertInstanceOf($o)) {
+			$o->foo();
+		}
+
+		$o = $this->createStdSat();
+		StdSat::assertInstanceOf2($o);
+		$o->foo();
+
+		$o = $this->createStdSat();
+		StdSat::assertInstanceOf3($o);
+		$o->foo();
+	}
+}