added regression test

Author: clxmstaab

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -1067,6 +1067,7 @@ public function dataFileAsserts(): iterable
 		yield from $this->gatherAssertTypes(__DIR__ . '/../Rules/Properties/data/bug-7839.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/self-out.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/native-expressions.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/../Rules/Classes/data/bug-5333.php');
 	}
 
 	/**

tests/PHPStan/Rules/Classes/ImpossibleInstanceOfRuleTest.php

@@ -346,4 +346,16 @@ public function testBug6213(): void
 		$this->analyse([__DIR__ . '/data/bug-6213.php'], []);
 	}
 
+	public function testBug5333(): void
+	{
+		$this->checkAlwaysTrueInstanceOf = true;
+		$this->treatPhpDocTypesAsCertain = false;
+		$this->analyse([__DIR__ . '/data/bug-5333.php'], [
+			[
+				'Instanceof between Bug5333\FinalRoute and Bug5333\FinalRoute will always evaluate to true.',
+				113,
+			],
+		]);
+	}
+
 }

tests/PHPStan/Rules/Classes/data/bug-5333.php

@@ -0,0 +1,122 @@
+<?php declare(strict_types = 1);
+
+namespace Bug5333;
+
+use function PHPStan\Testing\assertNativeType;
+use function PHPStan\Testing\assertType;
+
+class Route {}
+final class FinalRoute {}
+
+class HelloWorld
+{
+	/**
+	 * @param Route|Route[] $foo
+	 *
+	 * @return Route
+	 **/
+	public function sayHello($foo): Route
+	{
+		if (\is_array($foo)) {
+			$res = $foo[0];
+			assertType('Bug5333\Route', $res);
+			assertNativeType('mixed', $res);
+
+			if (!$res instanceof Route) {
+				throw new \Exception();
+			}
+
+			assertType('array<Bug5333\Route>', $foo);
+			assertNativeType('array', $foo);
+
+			assertType('Bug5333\Route', $res);
+			assertNativeType('Bug5333\Route', $res);
+
+			return $res;
+		}
+
+		return $foo;
+	}
+}
+
+class HelloWorld2
+{
+	/**
+	 * @var Route|callable():Route
+	 **/
+	private $foo;
+
+	/**
+	 * @param Route|callable():Route $foo
+	 **/
+	public function setFoo($foo): void
+	{
+		assertType('Bug5333\Route|(callable(): Bug5333\Route)', $foo);
+		assertNativeType('mixed', $foo);
+
+		$this->foo = $foo;
+	}
+
+	public function getFoo(): Route
+	{
+		assertType('Bug5333\Route|(callable(): Bug5333\Route)', $this->foo);
+		assertNativeType('Bug5333\Route|(callable(): Bug5333\Route)', $this->foo);
+
+		if (\is_callable($this->foo)) {
+			assertType('(Bug5333\Route&callable(): mixed)|(callable(): Bug5333\Route)', $this->foo);
+			assertNativeType('(Bug5333\Route&callable(): mixed)|(callable(): Bug5333\Route)', $this->foo);
+
+			$res = ($this->foo)();
+			assertType('mixed', $res);
+			assertNativeType('mixed', $res);
+			if (!$res instanceof Route) {
+				throw new \Exception();
+			}
+
+			return $res;
+		}
+
+		return $this->foo;
+	}
+}
+
+class HelloFinalWorld
+{
+	/**
+	 * @var FinalRoute|callable():FinalRoute
+	 **/
+	private $foo;
+
+	/**
+	 * @param FinalRoute|callable():FinalRoute $foo
+	 **/
+	public function setFoo($foo): void
+	{
+		assertType('Bug5333\FinalRoute|(callable(): Bug5333\FinalRoute)', $foo);
+		assertNativeType('mixed', $foo);
+
+		$this->foo = $foo;
+	}
+
+	public function getFoo(): FinalRoute
+	{
+		assertType('Bug5333\FinalRoute|(callable(): Bug5333\FinalRoute)', $this->foo);
+		assertNativeType('Bug5333\FinalRoute|(callable(): Bug5333\FinalRoute)', $this->foo);
+
+		if (\is_callable($this->foo)) {
+			assertType('callable(): Bug5333\FinalRoute', $this->foo);
+			assertNativeType('callable(): Bug5333\FinalRoute', $this->foo);
+
+			$res = ($this->foo)();
+			assertType('Bug5333\FinalRoute', $res);
+			assertNativeType('Bug5333\FinalRoute', $res);
+			if (!$res instanceof FinalRoute) {
+				throw new \Exception();
+			}
+
+			return $res;
+		}
+
+		return $this->foo;
+	}
+}