Allow normalizing empty stdClass

CHANGELOG.md

@@ -1,3 +1,9 @@
+1.3.2
+=====
+
+* (improvement) Allow normalizing empty `stdClass`.
+
+
 1.3.1
 =====
 

composer.json

@@ -17,7 +17,7 @@
 		"symfony/http-kernel": "^6.4 || ^7.0"
 	},
 	"require-dev": {
-		"21torr/janus": "^1.3",
+		"21torr/janus": "^1.4",
 		"bamarni/composer-bin-plugin": "^1.8",
 		"doctrine/common": "^3.4",
 		"roave/security-advisories": "dev-latest",

src/Normalizer/SimpleNormalizer.php

@@ -40,6 +40,13 @@ public function normalize (mixed $value, array $context = []) : mixed
 
 		if (\is_object($value))
 		{
+			// Allow empty stdClass as a way to force a JSON {} instead of an
+			// array which would encode to []
+			if ($value instanceof \stdClass && [] === get_object_vars($value))
+			{
+				return $value;
+			}
+
 			try
 			{
 				$className = $value::class;
@@ -56,14 +63,14 @@ public function normalize (mixed $value, array $context = []) : mixed
 			}
 			catch (ServiceNotFoundException $exception)
 			{
-				throw new ObjectTypeNotSupportedException(sprintf(
+				throw new ObjectTypeNotSupportedException(\sprintf(
 					"Can't normalize type %s",
 					get_debug_type($value),
 				), 0, $exception);
 			}
 		}
 
-		throw new UnsupportedTypeException(sprintf(
+		throw new UnsupportedTypeException(\sprintf(
 			"Can't normalize type %s",
 			get_debug_type($value),
 		));

tests/Normalizer/ObjectNormalizationTest.php

@@ -43,6 +43,34 @@ public static function getNormalizedType () : string
 		self::assertSame(["id" => 42], $normalizer->normalize($value));
 	}
 
+	/**
+	 *
+	 */
+	public function testEmptyStdClass () : void
+	{
+		$normalizer = $this->createNormalizer();
+		$object = new \stdClass();
+
+		self::assertSame(
+			$object,
+			$normalizer->normalize($object),
+		);
+	}
+
+	/**
+	 *
+	 */
+	public function testNonEmptyStdClassIsInvalid () : void
+	{
+		$normalizer = $this->createNormalizer();
+		$object = new \stdClass();
+		$object->prop = 5;
+
+		$this->expectException(ObjectTypeNotSupportedException::class);
+		$this->expectExceptionMessage("Can't normalize type stdClass");
+		$normalizer->normalize($object);
+	}
+
 	/**
 	 *
 	 */