From 586c70c8d39a2ebad3b1b17c4b050dc4e5e6f05f Mon Sep 17 00:00:00 2001
From: orklah <ronan_morin@hotmail.com>
Date: Sun, 13 Feb 2022 17:43:40 +0100
Subject: [PATCH 1/4] Reconcile IsNotType between EnumCase and NamedObject

---
 .../Internal/Type/NegatedAssertionReconciler.php      | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/Psalm/Internal/Type/NegatedAssertionReconciler.php b/src/Psalm/Internal/Type/NegatedAssertionReconciler.php
index e710a8c3c7d..74f4d1cf782 100644
--- a/src/Psalm/Internal/Type/NegatedAssertionReconciler.php
+++ b/src/Psalm/Internal/Type/NegatedAssertionReconciler.php
@@ -16,7 +16,6 @@
 use Psalm\Type\Atomic;
 use Psalm\Type\Atomic\TArray;
 use Psalm\Type\Atomic\TClassString;
-use Psalm\Type\Atomic\TEmptyMixed;
 use Psalm\Type\Atomic\TEnumCase;
 use Psalm\Type\Atomic\TFalse;
 use Psalm\Type\Atomic\TFloat;
@@ -162,6 +161,14 @@ public static function reconcile(
             return $existing_var_type;
         }
 
+        if (!$is_equality && $assertion_type instanceof TNamedObject) {
+            foreach ($existing_var_type->getAtomicTypes() as $key => $type) {
+                if ($type instanceof TEnumCase && $type->value === $assertion_type->value) {
+                    $existing_var_type->removeType($key);
+                }
+            }
+        }
+
         $codebase = $statements_analyzer->getCodebase();
 
         if ($assertion_type instanceof TNamedObject
@@ -291,7 +298,7 @@ public static function reconcile(
 
             $failed_reconciliation = Reconciler::RECONCILIATION_EMPTY;
 
-            return new Union([new TEmptyMixed]);
+            return Type::getNever();
         }
 
         return $existing_var_type;

From 5f1b796af999d9eac549e0d0bac426605ff1580e Mon Sep 17 00:00:00 2001
From: orklah <ronan_morin@hotmail.com>
Date: Sun, 13 Feb 2022 17:50:43 +0100
Subject: [PATCH 2/4] redundant condition

---
 src/Psalm/Internal/Provider/StatementsProvider.php | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/Psalm/Internal/Provider/StatementsProvider.php b/src/Psalm/Internal/Provider/StatementsProvider.php
index f78bd3e83b9..d6d5d4abccc 100644
--- a/src/Psalm/Internal/Provider/StatementsProvider.php
+++ b/src/Psalm/Internal/Provider/StatementsProvider.php
@@ -155,10 +155,6 @@ public function getStatementsForFile(
 
             $existing_statements = $this->parser_cache_provider->loadExistingStatementsFromCache($file_path);
 
-            if ($existing_statements && !$existing_statements[0] instanceof PhpParser\Node\Stmt) {
-                $existing_statements = null;
-            }
-
             $existing_file_contents = $this->parser_cache_provider->loadExistingFileContentsFromCache($file_path);
 
             // this happens after editing temporary file

From aaf34d75734d4a238a00eab92f5f7c53aadad781 Mon Sep 17 00:00:00 2001
From: orklah <ronan_morin@hotmail.com>
Date: Sun, 13 Feb 2022 19:05:51 +0100
Subject: [PATCH 3/4] add test

---
 tests/EnumTest.php | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/tests/EnumTest.php b/tests/EnumTest.php
index 3297151ee2d..963614bd198 100644
--- a/tests/EnumTest.php
+++ b/tests/EnumTest.php
@@ -405,6 +405,35 @@ function foo(): int|Code|null
                 'ignored_issues' => [],
                 'php_version' => '8.1',
             ],
+            'EnumCaseReconciliation' => [
+                'code' => '<?php
+                    enum Code: int
+                    {
+                        case Ok = 0;
+                        case Fatal = 1;
+                    }
+
+                    function foo(): Code|null
+                    {
+                        return null;
+                    }
+
+                    $code = foo();
+                    $code1 = null;
+                    $code2 = null;
+                    if($code instanceof Code){
+                        $code1 = $code;
+                    }
+                    if(!$code instanceof Code){
+                        $code2 = $code;
+                    }',
+                'assertions' => [
+                    '$code1' => 'Code|null',
+                    '$code2' => 'null',
+                ],
+                'ignored_issues' => [],
+                'php_version' => '8.1',
+            ],
         ];
     }
 

From 093d9b28212d949e570a73cafbc96b93b4f7f1d8 Mon Sep 17 00:00:00 2001
From: orklah <ronan_morin@hotmail.com>
Date: Sun, 13 Feb 2022 19:44:12 +0100
Subject: [PATCH 4/4] allow use of an empty reconciliation if the type is from
 docblock

---
 src/Psalm/Internal/Type/NegatedAssertionReconciler.php | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/Psalm/Internal/Type/NegatedAssertionReconciler.php b/src/Psalm/Internal/Type/NegatedAssertionReconciler.php
index 74f4d1cf782..efdf02d80c6 100644
--- a/src/Psalm/Internal/Type/NegatedAssertionReconciler.php
+++ b/src/Psalm/Internal/Type/NegatedAssertionReconciler.php
@@ -298,7 +298,9 @@ public static function reconcile(
 
             $failed_reconciliation = Reconciler::RECONCILIATION_EMPTY;
 
-            return Type::getNever();
+            return $existing_var_type->from_docblock
+                ? Type::getMixed()
+                : Type::getNever();
         }
 
         return $existing_var_type;