Fix const reference in current context

src/Psalm/Internal/Analyzer/Statements/Expression/Fetch/ConstFetchAnalyzer.php

@@ -34,6 +34,7 @@ class ConstFetchAnalyzer
         Context $context
     ) {
         $const_name = implode('\\', $stmt->name->parts);
+
         switch (strtolower($const_name)) {
             case 'null':
                 $stmt->inferredType = Type::getNull();

src/Psalm/Internal/Analyzer/StatementsAnalyzer.php

@@ -1354,8 +1354,8 @@ class StatementsAnalyzer extends SourceAnalyzer implements StatementsSource
             }
         }
 
-        if ($context->hasVariable($const_name, $statements_analyzer)) {
-            return $context->vars_in_scope[$const_name];
+        if ($context->hasVariable($fq_const_name, $this)) {
+            return $context->vars_in_scope[$fq_const_name];
         }
 
         $file_path = $statements_analyzer->getRootFilePath();

tests/ConstantTest.php

@@ -374,6 +374,13 @@ class ConstantTest extends TestCase
                         echo ns2\cons2;
                     }',
             ],
+            'allowConstantToBeDefinedInNamespaceNadReferenced' => [
+                '<?php
+                    namespace ns;
+                    function func(): void {}
+                    define(__NAMESPACE__."\\cons", 0);
+                    cons;'
+            ],
         ];
     }