diff --git a/src/Drivers/JsonDriver.php b/src/Drivers/JsonDriver.php
index 41e22cd..6f3d4d8 100644
--- a/src/Drivers/JsonDriver.php
+++ b/src/Drivers/JsonDriver.php
@@ -11,11 +11,11 @@ class JsonDriver implements Driver
     public function serialize($data): string
     {
         if (is_string($data)) {
-            $data = json_decode($data, true);
+            $data = json_decode($data);
         }
 
-        if (! is_array($data)) {
-            throw new CantBeSerialized('Only strings can be serialized to json');
+        if (is_resource($data)) {
+            throw new CantBeSerialized('Resources can not be serialized to json');
         }
 
         return json_encode($data, JSON_PRETTY_PRINT).PHP_EOL;
diff --git a/tests/Unit/Drivers/JsonDriverTest.php b/tests/Unit/Drivers/JsonDriverTest.php
index 1af3253..7e8ab85 100644
--- a/tests/Unit/Drivers/JsonDriverTest.php
+++ b/tests/Unit/Drivers/JsonDriverTest.php
@@ -4,6 +4,7 @@
 
 use PHPUnit\Framework\TestCase;
 use Spatie\Snapshots\Drivers\JsonDriver;
+use Spatie\Snapshots\Exceptions\CantBeSerialized;
 
 class JsonDriverTest extends TestCase
 {
@@ -84,4 +85,39 @@ public function it_can_serialize_a_json_array_to_pretty_json()
 
         $this->assertEquals($expected, $driver->serialize(['foo', 'bar', 'baz']));
     }
+
+    /** @test */
+    public function it_can_serialize_a_empty_json_object_to_pretty_json()
+    {
+        $driver = new JsonDriver();
+
+        $expected = implode(PHP_EOL, [
+            '{',
+            '    "foo": {',
+            '        "bar": true',
+            '    },',
+            '    "baz": {}',
+            '}',
+            '',
+        ]);
+
+        $this->assertEquals($expected, $driver->serialize((object) [
+            'foo' => (object) [
+                'bar' => true,
+            ],
+            'baz' => (object) [],
+        ]));
+    }
+
+    /** @test */
+    public function it_can_not_serialize_resources()
+    {
+        $driver = new JsonDriver();
+
+        $this->expectException(CantBeSerialized::class);
+
+        $resource = fopen('.', 'r');
+
+        $driver->serialize($resource);
+    }
 }