From 3887506280c49b46f112441539b9ca5a1a44e98b Mon Sep 17 00:00:00 2001
From: Matt Brown <github@muglug.com>
Date: Mon, 12 Oct 2020 18:55:57 -0400
Subject: [PATCH] =?UTF-8?q?Don=E2=80=99t=20merge=20array=20and=20Traversab?=
 =?UTF-8?q?le=20to=20iterable=20when=20there=20are=20intersections?=
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---
 src/Psalm/Internal/Type/TypeCombination.php |  1 +
 tests/ArrayAccessTest.php                   | 12 ++++++++++++
 2 files changed, 13 insertions(+)

diff --git a/src/Psalm/Internal/Type/TypeCombination.php b/src/Psalm/Internal/Type/TypeCombination.php
index 072c4afc283..82a698ab2b9 100644
--- a/src/Psalm/Internal/Type/TypeCombination.php
+++ b/src/Psalm/Internal/Type/TypeCombination.php
@@ -261,6 +261,7 @@ public static function combineTypes(
                 || (isset($combination->named_object_types['Traversable'])
                     && $combination->named_object_types['Traversable']->from_docblock)
             )
+            && !$combination->extra_types
         ) {
             $array_param_types = $combination->array_type_params;
             $traversable_param_types = $combination->builtin_type_params['Traversable']
diff --git a/tests/ArrayAccessTest.php b/tests/ArrayAccessTest.php
index dcddb89e3de..13ef370d459 100644
--- a/tests/ArrayAccessTest.php
+++ b/tests/ArrayAccessTest.php
@@ -964,6 +964,18 @@ function foo(array $arr) : void {
                         }
                     }'
             ],
+            'arrayAccessOnArraylikeObjectOrArray' => [
+                '<?php
+                    /**
+                     * @param (Traversable<int, string>&ArrayAccess<int, string>)|array<int, string> $arr
+                     */
+                    function test($arr): string {
+                        return $arr[0] ?? "";
+                    }
+
+                    test(["a", "b"]);
+                    test(new ArrayObject(["a", "b"]));'
+            ],
         ];
     }