Fix decimal marshalling in specific locales

lib/Pheasant/Types/Decimal.php

@@ -34,4 +34,9 @@ public function unmarshal($value)
     {
         return (float)$value;
     }
+
+    public function marshal($value)
+    {
+        return str_replace(',', '.', (string)$value);
+    }
 }

tests/Pheasant/Tests/TypeMarshallingTest.php

@@ -93,6 +93,25 @@ public function testUnixTimestampTypesAreRoundTripped()
         $this->assertSame($llamaById->unixtime->getTimestamp(), $ts->getTimestamp());
     }
 
+    public function testDecimalTypesAreMarshalledCorrectInLocale()
+    {
+        $prevLocale = setlocale(LC_ALL, "0");
+
+        /**
+         * Locale with decimal_point = ","
+         * So a float 88.5 becomes 88,5.
+         */
+        setlocale(LC_ALL, 'nl_NL');
+
+        $object = new DomainObject(array('type'=>'Llama', 'weight' => 88.5));
+        $object->save();
+
+        $llamaById = DomainObject::byId(1);
+        $this->assertSame($llamaById->weight, 88.5);
+
+        setlocale(LC_ALL, $prevLocale);
+    }
+
     /**
      * @expectedException InvalidArgumentException
      */