Add support for draft-04 multipleOf.

Author: Michael Chiocca

src/JsonSchema/Constraints/Number.php

@@ -52,11 +52,16 @@ public function check($element, $schema = null, $path = null, $i = null)
             $this->addError($path, "must have a maximum value of " . $schema->maximum);
         }
 
-        // Verify divisibleBy
+        // Verify divisibleBy - Draft v3
         if (isset($schema->divisibleBy) && $this->fmod($element, $schema->divisibleBy) != 0) {
             $this->addError($path, "is not divisible by " . $schema->divisibleBy);
         }
 
+        // Verify multipleOf - Draft v4
+        if (isset($schema->multipleOf) && $this->fmod($element, $schema->multipleOf) != 0) {
+            $this->addError($path, "must be a multiple of " . $schema->multipleOf);
+        }
+
         $this->checkFormat($element, $schema, $path, $i);
     }
 

src/JsonSchema/Constraints/Undefined.php

@@ -143,12 +143,12 @@ protected function validateCommonProperties($value, $schema = null, $path = null
         if (is_object($value)) {
             if (isset($schema->minProperties)) {
                 if (count(get_object_vars($value)) < $schema->minProperties) {
-                    $this->addError($path, "must contain a minimum of " + $schema->minProperties + " properties");
+                    $this->addError($path, "must contain a minimum of " . $schema->minProperties . " properties");
                 }
             }
             if (isset($schema->maxProperties)) {
                 if (count(get_object_vars($value)) > $schema->maxProperties) {
-                    $this->addError($path, "must contain no more than " + $schema->maxProperties + " properties");
+                    $this->addError($path, "must contain no more than " . $schema->maxProperties . " properties");
                 }
             }
         }

tests/JsonSchema/Tests/Drafts/Draft4Test.php

@@ -19,7 +19,6 @@ protected function getSkippedTests()
             'allOf.json',
             'anyOf.json',
             'definitions.json',
-            'multipleOf.json',
             'not.json',
             'oneOf.json',
             // Partially Implemented