Fix objectType::getOffsetValueType

Author: VincentLanglet

src/Type/ObjectType.php

@@ -1228,14 +1228,14 @@ public function hasOffsetValueType(Type $offsetType): TrinaryLogic
 
 	public function getOffsetValueType(Type $offsetType): Type
 	{
-		if (!$this->isExtraOffsetAccessibleClass()->no()) {
-			return new MixedType();
-		}
-
 		if ($this->isInstanceOf(ArrayAccess::class)->yes()) {
 			return RecursionGuard::run($this, fn (): Type => $this->getMethod('offsetGet', new OutOfClassScope())->getOnlyVariant()->getReturnType());
 		}
 
+		if (!$this->isExtraOffsetAccessibleClass()->no()) {
+			return new MixedType();
+		}
+
 		return new ErrorType();
 	}
 

tests/PHPStan/Analyser/nsrt/bug-12125.php

@@ -0,0 +1,37 @@
+<?php declare(strict_types = 1);
+
+namespace Bug12125;
+
+use ArrayAccess;
+use Exception;
+use stdClass;
+
+use function PHPStan\Testing\assertType;
+
+/** @var ArrayAccess<array-key, stdClass>|array<array-key, stdClass> $bug */
+$bug = [];
+
+assertType('stdClass|null', $bug['key'] ?? null);
+
+interface MyInterface {
+	/** @return array<string, string> | ArrayAccess<string, string> */
+	public function getStrings(): array | ArrayAccess;
+}
+
+function myFunction(MyInterface $container): string {
+	$strings = $container->getStrings();
+	assertType('array<string, string>|ArrayAccess<string, string>', $strings);
+	assertType('string|null', $strings['test']);
+	return $strings['test'];
+}
+
+function myOtherFunction(MyInterface $container): string {
+	$strings = $container->getStrings();
+	assertType('array<string, string>|ArrayAccess<string, string>', $strings);
+	if (isset($strings['test'])) {
+		assertType('string', $strings['test']);
+		return $strings['test'];
+	} else {
+		throw new Exception();
+	}
+}