Added AliasType

src/AliasType.php

@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Typhoon\Type;
+
+/**
+ * @api
+ * @template-covariant TType
+ * @implements Type<TType>
+ */
+final class AliasType implements Type
+{
+    /**
+     * @var non-empty-string
+     */
+    public readonly string $class;
+
+    /**
+     * @var non-empty-string
+     */
+    public readonly string $name;
+
+    /**
+     * @internal
+     * @psalm-internal Typhoon\Type
+     * @param non-empty-string $class
+     * @param non-empty-string $name
+     */
+    public function __construct(
+        string $class,
+        string $name,
+    ) {
+        $this->class = $class;
+        $this->name = $name;
+    }
+
+    public function accept(TypeVisitor $visitor): mixed
+    {
+        return $visitor->visitAlias($this);
+    }
+}

src/TypeVisitor.php

@@ -118,6 +118,9 @@ public function visitTemplate(TemplateType $type): mixed;
     /** @return TReturn */
     public function visitConditional(ConditionalType $type): mixed;
 
+    /** @return TReturn */
+    public function visitAlias(AliasType $type): mixed;
+
     /** @return TReturn */
     public function visitIntersection(IntersectionType $type): mixed;
 

src/types.php

@@ -358,6 +358,15 @@ public static function conditional(Argument|TemplateType $subject, Type $if, Typ
         return new ConditionalType($subject, $if, $then, $else);
     }
 
+    /**
+     * @param non-empty-string $class
+     * @param non-empty-string $name
+     */
+    public static function alias(string $class, string $name): AliasType
+    {
+        return new AliasType($class, $name);
+    }
+
     /**
      * @param non-empty-string $name
      */

tests/PsalmTest.php

@@ -24,6 +24,7 @@ public static function extractType(Type $_type): mixed
         return null;
     }
 
+    #[TestWith([__DIR__ . '/psalm/AliasType.phpt'])]
     #[TestWith([__DIR__ . '/psalm/AnyLiteralIntType.phpt'])]
     #[TestWith([__DIR__ . '/psalm/AnyLiteralStringType.phpt'])]
     #[TestWith([__DIR__ . '/psalm/ArrayShapeType.phpt'])]

tests/psalm/AliasType.phpt

@@ -0,0 +1,9 @@
+--FILE--
+<?php
+
+namespace Typhoon\Type;
+
+$_type = PsalmTest::extractType(new AliasType('SomeClass', 'AliasType'));
+/** @psalm-check-type-exact $_type = mixed */
+
+--EXPECT--