Add support for trait string types

Author: jaapio

src/PseudoTypes/TraitString.php

@@ -24,16 +24,33 @@
  */
 final class TraitString extends String_ implements PseudoType
 {
+    /** @var Type|null */
+    private $genericType;
+
+    public function __construct(?Type $genericType = null)
+    {
+        $this->genericType = $genericType;
+    }
+
     public function underlyingType(): Type
     {
         return new String_();
     }
 
+    public function getGenericType(): ?Type
+    {
+        return $this->genericType;
+    }
+
     /**
      * Returns a rendered output of the Type as it would be used in a DocBlock.
      */
     public function __toString(): string
     {
-        return 'trait-string';
+        if ($this->genericType === null) {
+            return 'trait-string';
+        }
+
+        return 'trait-string<' . (string) $this->genericType . '>';
     }
 }

src/TypeResolver.php

@@ -406,6 +406,9 @@ private function createFromGeneric(GenericTypeNode $type, Context $context): Typ
             case 'interface-string':
                 return new InterfaceString($this->createType($type->genericTypes[0], $context));
 
+            case 'trait-string':
+                return new TraitString($this->createType($type->genericTypes[0], $context));
+
             case 'list':
                 return new List_(
                     $this->createType($type->genericTypes[0], $context)

tests/unit/TypeResolverTest.php

@@ -1115,6 +1115,23 @@ public function genericsProvider(): array
                     ])
                 ),
             ],
+            [
+                'trait-string',
+                new TraitString(),
+            ],
+            [
+                'trait-string<Foo>',
+                new TraitString(new Object_(new Fqsen('\\phpDocumentor\\Foo'))),
+            ],
+            [
+                'trait-string<Foo|Bar>',
+                new TraitString(
+                    new Compound([
+                        new Object_(new Fqsen('\\phpDocumentor\\Foo')),
+                        new Object_(new Fqsen('\\phpDocumentor\\Bar')),
+                    ])
+                ),
+            ],
             [
                 'List<Foo>',
                 new List_(new Object_(new Fqsen('\\phpDocumentor\\Foo'))),