From 40ce0cf7d7fc026696ec90c677fd8b130e788d2c Mon Sep 17 00:00:00 2001
From: Yannick Gottschalk <ygottschalk@techfak.uni-bielefeld.de>
Date: Mon, 12 Jun 2023 15:24:30 +0200
Subject: [PATCH 1/2] Fixes #9827

---
 src/Psalm/Internal/Type/TypeCombiner.php |  4 +++-
 tests/TypeCombinationTest.php            | 22 ++++++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/src/Psalm/Internal/Type/TypeCombiner.php b/src/Psalm/Internal/Type/TypeCombiner.php
index 0daa9d29684..d091c239961 100644
--- a/src/Psalm/Internal/Type/TypeCombiner.php
+++ b/src/Psalm/Internal/Type/TypeCombiner.php
@@ -130,7 +130,9 @@ public static function combine(
         if (count($combination->value_types) === 1
             && !count($combination->objectlike_entries)
             && (!$combination->array_type_params
-                || $combination->array_type_params[1]->isNever()
+                || ( $overwrite_empty_array
+                    && $combination->array_type_params[1]->isNever()
+                )
             )
             && !$combination->builtin_type_params
             && !$combination->object_type_params
diff --git a/tests/TypeCombinationTest.php b/tests/TypeCombinationTest.php
index 2b85c551761..c2499ab96a3 100644
--- a/tests/TypeCombinationTest.php
+++ b/tests/TypeCombinationTest.php
@@ -338,6 +338,28 @@ public function providerTestValidTypeCombination(): array
                     'ArrayObject<int, string>',
                 ],
             ],
+            'emptyArrayAndFalse' => [
+                'array<never, never>|false',
+                [
+                    'array<never, never>',
+                    'false'
+                ]
+            ],
+            'emptyArrayAndTrue' => [
+                'array<never, never>|true',
+                [
+                    'array<never, never>',
+                    'true'
+                ]
+            ],
+            'emptyArrayWithTrueAndFalse' => [
+                'array<never, never>|bool',
+                [
+                    'array<never, never>',
+                    'true',
+                    'false'
+                ]
+            ],
             'falseDestruction' => [
                 'bool',
                 [

From d11bb90c967f76011d2bc02438ca555a2ebe572f Mon Sep 17 00:00:00 2001
From: Yannick Gottschalk <ygottschalk@techfak.uni-bielefeld.de>
Date: Mon, 12 Jun 2023 15:29:22 +0200
Subject: [PATCH 2/2] Style fixes

---
 tests/TypeCombinationTest.php | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/tests/TypeCombinationTest.php b/tests/TypeCombinationTest.php
index c2499ab96a3..5a74bc01266 100644
--- a/tests/TypeCombinationTest.php
+++ b/tests/TypeCombinationTest.php
@@ -342,23 +342,23 @@ public function providerTestValidTypeCombination(): array
                 'array<never, never>|false',
                 [
                     'array<never, never>',
-                    'false'
-                ]
+                    'false',
+                ],
             ],
             'emptyArrayAndTrue' => [
                 'array<never, never>|true',
                 [
                     'array<never, never>',
-                    'true'
-                ]
+                    'true',
+                ],
             ],
             'emptyArrayWithTrueAndFalse' => [
                 'array<never, never>|bool',
                 [
                     'array<never, never>',
                     'true',
-                    'false'
-                ]
+                    'false',
+                ],
             ],
             'falseDestruction' => [
                 'bool',