Fix

Author: samsonasik

src/PHPStanStaticTypeMapper/TypeMapper/UnionTypeMapper.php

@@ -19,6 +19,7 @@
 use PHPStan\Type\Type;
 use PHPStan\Type\UnionType;
 use Rector\BetterPhpDocParser\ValueObject\Type\BracketsAwareUnionTypeNode;
+use Rector\BetterPhpDocParser\ValueObject\Type\SpacingAwareArrayTypeNode;
 use Rector\NodeAnalyzer\PropertyAnalyzer;
 use Rector\Php\PhpVersionProvider;
 use Rector\PHPStanStaticTypeMapper\Contract\TypeMapperInterface;
@@ -57,13 +58,32 @@ public function getNodeClass(): string
     public function mapToPHPStanPhpDocTypeNode(Type $type): TypeNode
     {
         $unionTypesNodes = [];
+        $existingTypes = [];
+
         foreach ($type->getTypes() as $unionedType) {
             if ($unionedType instanceof ArrayType && $unionedType->getItemType() instanceof NeverType) {
                 $unionedType = new ArrayType($unionedType->getKeyType(), new MixedType());
             }
 
-            // here to debug ...
-            $unionTypesNodes[] = $this->phpStanStaticTypeMapper->mapToPHPStanPhpDocTypeNode($unionedType);
+            $unionedType = $this->phpStanStaticTypeMapper->mapToPHPStanPhpDocTypeNode($unionedType);
+
+            if ($unionedType instanceof SpacingAwareArrayTypeNode && $unionedType->type instanceof BracketsAwareUnionTypeNode) {
+                foreach ($unionedType->type->types as $key => $innerTypeNode) {
+                    $printedInnerType = (string) $innerTypeNode;
+                    if (in_array($printedInnerType, $existingTypes, true)) {
+                        unset($unionedType->type->types[$key]);
+                        continue;
+                    }
+
+                    $existingTypes[] = $printedInnerType;
+                }
+
+                if ($unionedType->type->types === []) {
+                    continue;
+                }
+            }
+
+            $unionTypesNodes[] = $unionedType;
         }
 
         return new BracketsAwareUnionTypeNode($unionTypesNodes);