Adjust string type casting with HTML data

Author: stloyd

src/lib/types/src/Flow/Types/Type/Native/StringType.php

@@ -5,6 +5,7 @@
 namespace Flow\Types\Type\Native;
 
 use function Flow\Types\DSL\dom_element_to_string;
+use Dom\{HTMLDocument, HTMLElement};
 use Flow\Types\Exception\{CastingException, InvalidTypeException};
 use Flow\Types\Type;
 
@@ -57,6 +58,14 @@ public function cast(mixed $value) : string
                 return (string) dom_element_to_string($value);
             }
 
+            if ($value instanceof HTMLDocument) {
+                return $value->saveHtml();
+            }
+
+            if ($value instanceof HTMLElement) {
+                return $value->innerHTML;
+            }
+
             if (null === $value) {
                 return '';
             }

src/lib/types/tests/Flow/Types/Tests/Unit/Type/Native/StringTypeTest.php

@@ -5,9 +5,10 @@
 namespace Flow\Types\Tests\Unit\Type\Native;
 
 use function Flow\Types\DSL\{type_from_array, type_string};
+use Dom\HTMLDocument;
 use Flow\Types\Exception\InvalidTypeException;
 use Flow\Types\Tests\Unit\Type\Fixtures\StringableObject;
-use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\Attributes\{DataProvider, RequiresPhp};
 use PHPUnit\Framework\TestCase;
 
 final class StringTypeTest extends TestCase
@@ -215,6 +216,22 @@ public function test_cast(mixed $value, mixed $expected, ?string $exceptionClass
         }
     }
 
+    #[RequiresPhp('>= 8.4')]
+    public function test_cast_html_document() : void
+    {
+        $element = HTMLDocument::createFromString('<p><span>foobar</span></p>', \LIBXML_HTML_NOIMPLIED | \LIBXML_NOERROR);
+
+        self::assertSame('<p><span>foobar</span></p>', type_string()->cast($element));
+    }
+
+    #[RequiresPhp('>= 8.4')]
+    public function test_cast_html_element() : void
+    {
+        $element = HTMLDocument::createFromString('<p><span>foobar</span></p>', \LIBXML_HTML_NOIMPLIED | \LIBXML_NOERROR);
+
+        self::assertSame('<span>foobar</span>', type_string()->cast($element->documentElement));
+    }
+
     #[DataProvider('is_stringable_data_provider')]
     public function test_is_stringable(mixed $value, bool $expected) : void
     {