From 19fd10ba7b78f341af72bb5486b46bd49e0b897a Mon Sep 17 00:00:00 2001
From: Matthew Brown <github@muglug.com>
Date: Wed, 15 Dec 2021 11:31:59 +0000
Subject: [PATCH] Remove unnecessary references to empty in TypeCombiner

---
 src/Psalm/Internal/Type/TypeCombiner.php | 11 ++++-------
 tests/TypeCombinationTest.php            |  8 ++++----
 2 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/src/Psalm/Internal/Type/TypeCombiner.php b/src/Psalm/Internal/Type/TypeCombiner.php
index a693f38896d..432432b7ba4 100644
--- a/src/Psalm/Internal/Type/TypeCombiner.php
+++ b/src/Psalm/Internal/Type/TypeCombiner.php
@@ -79,7 +79,7 @@ class TypeCombiner
      *  - so `int + string = int|string`
      *  - so `array<int> + array<string> = array<int|string>`
      *  - and `array<int> + string = array<int>|string`
-     *  - and `array<empty> + array<empty> = array<empty>`
+     *  - and `array<never> + array<never> = array<never>`
      *  - and `array<string> + array<empty> = array<string>`
      *  - and `array + array<string> = array<mixed>`
      *
@@ -337,20 +337,17 @@ public static function combine(
             $combination->value_types += $combination->named_object_types;
         }
 
-        $has_empty = (int) (isset($combination->value_types['never']) || isset($combination->value_types['empty']));
-        $has_never = false;
+        $has_never = isset($combination->value_types['never']);
 
         foreach ($combination->value_types as $type) {
             if ($type instanceof TMixed
                 && $combination->mixed_from_loop_isset
-                && (count($combination->value_types) > (1 + $has_empty) || count($new_types) > $has_empty)
+                && (count($combination->value_types) > (1 + (int) $has_never) || count($new_types) > (int) $has_never)
             ) {
                 continue;
             }
 
-            if (($type instanceof TNever || $type instanceof TAssertionEmpty)
-                && (count($combination->value_types) > 1 || count($new_types))
-            ) {
+            if ($type instanceof TNever && (count($combination->value_types) > 1 || count($new_types))) {
                 $has_never = true;
                 continue;
             }
diff --git a/tests/TypeCombinationTest.php b/tests/TypeCombinationTest.php
index f1330e20717..fff9eaf8992 100644
--- a/tests/TypeCombinationTest.php
+++ b/tests/TypeCombinationTest.php
@@ -108,10 +108,10 @@ public function providerTestValidTypeCombination(): array
                     'null',
                 ],
             ],
-            'mixedOrEmpty' => [
+            'mixedOrNever' => [
                 'mixed',
                 [
-                    'empty',
+                    'never',
                     'mixed',
                 ],
             ],
@@ -205,7 +205,7 @@ public function providerTestValidTypeCombination(): array
             'arrayStringOrEmptyArray' => [
                 'array<array-key, string>',
                 [
-                    'array<empty>',
+                    'array<never>',
                     'array<string>',
                 ],
             ],
@@ -226,7 +226,7 @@ public function providerTestValidTypeCombination(): array
             'arrayMixedOrEmpty' => [
                 'array<array-key, mixed>',
                 [
-                    'array<empty>',
+                    'array<never>',
                     'array<mixed>',
                 ],
             ],