fix invalid float denormalization without decimal part

camilledejoye · camilledejoye · commit 3c9f914797f0 · 2020-11-22T19:15:11.000+01:00
diff --git a/src/Symfony/Component/Serializer/Normalizer/ScalarDenormalizer.php b/src/Symfony/Component/Serializer/Normalizer/ScalarDenormalizer.php
@@ -11,6 +11,8 @@
 
 namespace Symfony\Component\Serializer\Normalizer;
 
+use Symfony\Component\PropertyInfo\Type;
+use Symfony\Component\Serializer\Encoder\JsonEncoder;
 use Symfony\Component\Serializer\Exception\InvalidArgumentException;
 use Symfony\Component\Serializer\Exception\NotNormalizableValueException;
 
@@ -32,6 +34,16 @@ public function denormalize($data, string $type, string $format = null, array $c
             throw new InvalidArgumentException(sprintf('Data expected to be of one of the types in "%s" ("%s" given).', implode(', ', array_keys(self::SCALAR_TYPES)), get_debug_type($data)));
         }
 
+        // JSON only has a Number type corresponding to both int and float PHP types.
+        // PHP's json_encode, JavaScript's JSON.stringify, Go's json.Marshal as well as most other JSON encoders convert
+        // floating-point numbers like 12.0 to 12 (the decimal part is dropped when possible).
+        // PHP's json_decode automatically converts Numbers without a decimal part to integers.
+        // To circumvent this behavior, integers are converted to floats when denormalizing JSON based formats and when
+        // a float is expected.
+        if (Type::BUILTIN_TYPE_FLOAT === $type && \is_int($data) && false !== strpos($format, JsonEncoder::FORMAT)) {
+            return (float) $data;
+        }
+
         if (!('is_'.$type)($data)) {
             throw new NotNormalizableValueException(sprintf('Data expected to be of type "%s" ("%s" given).', $type, get_debug_type($data)));
         }
diff --git a/src/Symfony/Component/Serializer/Tests/SerializerTest.php b/src/Symfony/Component/Serializer/Tests/SerializerTest.php
@@ -564,6 +564,7 @@ public function testDeserializeScalar()
         $this->assertTrue($serializer->deserialize('true', 'bool', 'json'));
         $this->assertSame(3.14, $serializer->deserialize('3.14', 'float', 'json'));
         $this->assertSame(3.14, $serializer->deserialize('31.4e-1', 'float', 'json'));
+        $this->assertSame(3.0, $serializer->deserialize('3', 'float', 'json')); // '3' === json_encode(3.0)
         $this->assertSame('  spaces  ', $serializer->deserialize('"  spaces  "', 'string', 'json'));
         $this->assertSame('@Ca$e%', $serializer->deserialize('"@Ca$e%"', 'string', 'json'));
     }

Original file line number	Diff line number	Diff line change
`@@ -564,6 +564,7 @@ public function testDeserializeScalar()`
`564`	`564`	`$this->assertTrue($serializer->deserialize('true', 'bool', 'json'));`
`565`	`565`	`$this->assertSame(3.14, $serializer->deserialize('3.14', 'float', 'json'));`
`566`	`566`	`$this->assertSame(3.14, $serializer->deserialize('31.4e-1', 'float', 'json'));`
	`567`	`+ $this->assertSame(3.0, $serializer->deserialize('3', 'float', 'json')); // '3' === json_encode(3.0)`
`567`	`568`	`$this->assertSame(' spaces ', $serializer->deserialize('" spaces "', 'string', 'json'));`
`568`	`569`	`$this->assertSame('@Ca$e%', $serializer->deserialize('"@Ca$e%"', 'string', 'json'));`
`569`	`570`	`}`