Use TypeAlias object to allow future extension

src/Psalm/Internal/Analyzer/CommentAnalyzer.php

@@ -12,6 +12,7 @@
 use Psalm\Internal\Scanner\FunctionDocblockComment;
 use Psalm\Internal\Scanner\VarDocblockComment;
 use Psalm\Internal\Type\ParseTree;
+use Psalm\Internal\Type\TypeAlias;
 use Psalm\Internal\Type\TypeParser;
 use Psalm\Internal\Type\TypeTokenizer;
 use Psalm\Type;
@@ -46,7 +47,7 @@ class CommentAnalyzer
 
     /**
      * @param  array<string, array<string, array{Type\Union}>>|null   $template_type_map
-     * @param  array<string, array<int, array{0: string, 1: int}>> $type_aliases
+     * @param  array<string, TypeAlias> $type_aliases
      *
      * @throws DocblockParseException if there was a problem parsing the docblock
      *
@@ -73,7 +74,7 @@ public static function getTypeFromComment(
 
     /**
      * @param  array<string, array<string, array{Type\Union}>>|null   $template_type_map
-     * @param  array<string, array<int, array{0: string, 1: int}>> $type_aliases
+     * @param  array<string, TypeAlias> $type_aliases
      * @param array{description:string, specials:array<string, array<int, string>>} $parsed_docblock
      *
      * @return VarDocblockComment[]
@@ -240,11 +241,11 @@ private static function sanitizeDocblockType(string $docblock_type) : string
 
     /**
      * @param  Aliases          $aliases
-     * @param  array<string, array<int, array{0: string, 1: int}>> $type_aliases
+     * @param  array<string, TypeAlias> $type_aliases
      *
      * @throws DocblockParseException if there was a problem parsing the docblock
      *
-     * @return array<string, list<array{0: string, 1: int}>>
+     * @return array<string, TypeAlias>
      */
     public static function getTypeAliasesFromComment(
         PhpParser\Comment\Doc $comment,
@@ -267,11 +268,11 @@ public static function getTypeAliasesFromComment(
     /**
      * @param  array<string>    $type_alias_comment_lines
      * @param  Aliases          $aliases
-     * @param  array<string, array<int, array{0: string, 1: int}>> $type_aliases
+     * @param  array<string, TypeAlias> $type_aliases
      *
      * @throws DocblockParseException if there was a problem parsing the docblock
      *
-     * @return array<string, list<array{0: string, 1: int}>>
+     * @return array<string, TypeAlias>
      */
     private static function getTypeAliasesFromCommentLines(
         array $type_alias_comment_lines,
@@ -335,7 +336,7 @@ private static function getTypeAliasesFromCommentLines(
                 throw new DocblockParseException($type_string . ' is not a valid type');
             }
 
-            $type_alias_tokens[$type_alias] = $type_tokens;
+            $type_alias_tokens[$type_alias] = new TypeAlias($type_tokens);
         }
 
         return $type_alias_tokens;

src/Psalm/Internal/PhpVisitor/ReflectorVisitor.php

@@ -42,6 +42,7 @@
 use Psalm\Internal\Scanner\PhpStormMetaScanner;
 use Psalm\Internal\Scanner\UnresolvedConstant;
 use Psalm\Internal\Scanner\UnresolvedConstantComponent;
+use Psalm\Internal\Type\TypeAlias;
 use Psalm\Internal\Type\TypeParser;
 use Psalm\Internal\Type\TypeTokenizer;
 use Psalm\Issue\DuplicateClass;
@@ -127,7 +128,7 @@ class ReflectorVisitor extends PhpParser\NodeVisitorAbstract implements PhpParse
     private $skip_if_descendants = null;
 
     /**
-     * @var array<string, array<int, array{0: string, 1: int}>>
+     * @var array<string, TypeAlias>
      */
     private $type_aliases = [];
 
@@ -164,9 +165,11 @@ public function enterNode(PhpParser\Node $node)
                         $this->type_aliases
                     );
 
-                    foreach ($type_alias_tokens as $type_tokens) {
-                        // finds issues, if there are any
-                        TypeParser::parseTokens($type_tokens);
+                    foreach ($type_alias_tokens as $type_alias) {
+                        if ($type_alias->replacement_tokens) {
+                            // finds issues, if there are any
+                            TypeParser::parseTokens($type_alias->replacement_tokens);
+                        }
                     }
 
                     $this->type_aliases += $type_alias_tokens;

src/Psalm/Internal/Type/TypeAlias.php

@@ -0,0 +1,18 @@
+<?php
+namespace Psalm\Internal\Type;
+
+class TypeAlias
+{
+    /**
+     * @var list<array{0: string, 1: int}>|null
+     */
+    public $replacement_tokens = null;
+
+    /**
+     * @param list<array{0: string, 1: int}>|null $replacement_tokens
+     */
+    public function __construct(?array $replacement_tokens)
+    {
+        $this->replacement_tokens = $replacement_tokens;
+    }
+}

src/Psalm/Internal/Type/TypeTokenizer.php

@@ -322,8 +322,8 @@ public static function fixScalarTerms(
     }
 
     /**
-     * @param  array<string, mixed>|null    $template_type_map
-     * @param  array<string, array<int, array{0: string, 1: int}>>|null   $type_aliases
+     * @param  array<string, mixed>|null       $template_type_map
+     * @param  array<string, TypeAlias>|null   $type_aliases
      *
      * @return list<array{0: string, 1: int}>
      */
@@ -443,17 +443,21 @@ public static function getFullyQualifiedTokens(
             }
 
             if (isset($type_aliases[$string_type_token[0]])) {
-                $replacement_tokens = $type_aliases[$string_type_token[0]];
+                $type_alias = $type_aliases[$string_type_token[0]];
 
-                array_unshift($replacement_tokens, ['(', $i]);
-                array_push($replacement_tokens, [')', $i]);
+                if ($type_alias->replacement_tokens) {
+                    $replacement_tokens = $type_alias->replacement_tokens;
 
-                $diff = count($replacement_tokens) - 1;
+                    array_unshift($replacement_tokens, ['(', $i]);
+                    array_push($replacement_tokens, [')', $i]);
 
-                array_splice($type_tokens, $i, 1, $replacement_tokens);
+                    $diff = count($replacement_tokens) - 1;
 
-                $i += $diff;
-                $l += $diff;
+                    array_splice($type_tokens, $i, 1, $replacement_tokens);
+
+                    $i += $diff;
+                    $l += $diff;
+                }
             } else {
                 $type_tokens[$i][0] = \Psalm\Type::getFQCLNFromString(
                     $string_type_token[0],

src/Psalm/Storage/FileStorage.php

@@ -82,7 +82,7 @@ class FileStorage
     public $docblock_issues = [];
 
     /**
-     * @var array<string, array<int, array{0: string, 1: int}>>
+     * @var array<string, \Psalm\Internal\Type\TypeAlias>
      */
     public $type_aliases = [];