regression test

Author: staabm

tests/PHPStan/Rules/Methods/ReturnTypeRuleTest.php

@@ -1276,4 +1276,9 @@ public function testBug9494(): void
 		$this->analyse([__DIR__ . '/data/bug-9494.php'], []);
 	}
 
+	public function testBug8438(): void
+	{
+		$this->analyse([__DIR__ . '/data/bug-8438.php'], []);
+	}
+
 }

tests/PHPStan/Rules/Methods/data/bug-8438.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace Bug8438;
+
+class HelloWorld
+{
+	/**
+	 * @param array<string, string> $array
+	 *
+	 * @return array{expr: mixed, ...}
+	 */
+	protected function foo(array $array): array
+	{
+		$rnd = mt_rand();
+		if ($rnd === 0) {
+			return ['expr' => 'test'];
+		} elseif ($rnd === 1) {
+			// no error with checkBenevolentUnionTypes: false (default even with l9 + strict rules)
+			return ['expr' => 'test', 1 => 'ok'];
+		} else {
+			// phpstan must understand 'expr' key is always present in the result,
+			// then there will be no error here neither
+			return array_merge($array, ['expr' => 'test', 1 => 'ok']);
+		}
+	}
+}