[Serializer] fix upper camel case conversion (see #21399)

Author: markusu49

NameConverter/CamelCaseToSnakeCaseNameConverter.php

@@ -44,14 +44,15 @@ public function __construct(array $attributes = null, $lowerCamelCase = true)
     public function normalize($propertyName)
     {
         if (null === $this->attributes || in_array($propertyName, $this->attributes)) {
+            $lcPropertyName = lcfirst($propertyName);
             $snakeCasedName = '';
 
-            $len = strlen($propertyName);
+            $len = strlen($lcPropertyName);
             for ($i = 0; $i < $len; ++$i) {
-                if (ctype_upper($propertyName[$i])) {
-                    $snakeCasedName .= '_'.strtolower($propertyName[$i]);
+                if (ctype_upper($lcPropertyName[$i])) {
+                    $snakeCasedName .= '_'.strtolower($lcPropertyName[$i]);
                 } else {
-                    $snakeCasedName .= strtolower($propertyName[$i]);
+                    $snakeCasedName .= strtolower($lcPropertyName[$i]);
                 }
             }
 

Tests/NameConverter/CamelCaseToSnakeCaseNameConverterTest.php

@@ -27,27 +27,30 @@ public function testInterface()
     /**
      * @dataProvider attributeProvider
      */
-    public function testNormalize($underscored, $lowerCamelCased)
+    public function testNormalize($underscored, $camelCased, $useLowerCamelCase)
     {
-        $nameConverter = new CamelCaseToSnakeCaseNameConverter();
-        $this->assertEquals($nameConverter->normalize($lowerCamelCased), $underscored);
+        $nameConverter = new CamelCaseToSnakeCaseNameConverter(null, $useLowerCamelCase);
+        $this->assertEquals($nameConverter->normalize($camelCased), $underscored);
     }
 
     /**
      * @dataProvider attributeProvider
      */
-    public function testDenormalize($underscored, $lowerCamelCased)
+    public function testDenormalize($underscored, $camelCased, $useLowerCamelCase)
     {
-        $nameConverter = new CamelCaseToSnakeCaseNameConverter();
-        $this->assertEquals($nameConverter->denormalize($underscored), $lowerCamelCased);
+        $nameConverter = new CamelCaseToSnakeCaseNameConverter(null, $useLowerCamelCase);
+        $this->assertEquals($nameConverter->denormalize($underscored), $camelCased);
     }
 
     public function attributeProvider()
     {
         return array(
-            array('coop_tilleuls', 'coopTilleuls'),
-            array('_kevin_dunglas', '_kevinDunglas'),
-            array('this_is_a_test', 'thisIsATest'),
+            array('coop_tilleuls', 'coopTilleuls', true),
+            array('_kevin_dunglas', '_kevinDunglas', true),
+            array('this_is_a_test', 'thisIsATest', true),
+            array('coop_tilleuls', 'CoopTilleuls', false),
+            array('_kevin_dunglas', '_kevinDunglas', false),
+            array('this_is_a_test', 'ThisIsATest', false),
         );
     }
 }