Added validate function with callback + tests

Validator/Validator.swift

@@ -57,6 +57,21 @@ public class Validator {
         }
     }
     
+    public func validate(callback:(errors:[UITextField:ValidationError])->Void) -> Void {
+        
+        for field in validations.keys {
+            if let currentRule:ValidationRule = validations[field] {
+                if var error:ValidationError = currentRule.validateField() {
+                    errors[field] = error
+                } else {
+                    errors.removeValueForKey(field)
+                }
+            }
+        }
+        
+        callback(errors: errors)
+    }
+    
     func clearErrors() {
         self.errors = [:]
     }

ValidatorTests/ValidatorTests.swift

@@ -164,4 +164,18 @@ class ValidatorTests: XCTestCase {
         UNREGISTER_VALIDATOR.unregisterField(UNREGISTER_TXT_FIELD)
         XCTAssert(UNREGISTER_VALIDATOR.validations[UNREGISTER_TXT_FIELD] == nil, "Textfield should unregister")
     }
+    
+    // MARK: Validate Functions
+    
+    func testValidateWithCallback() {
+        REGISTER_VALIDATOR.registerField(REGISTER_TXT_FIELD, rules: [EmailRule()])
+        REGISTER_TXT_FIELD.text = VALID_EMAIL
+        REGISTER_VALIDATOR.validate { (errors) -> Void in
+            XCTAssert(errors.count == 0, "Should not come back with errors")
+        }
+        REGISTER_TXT_FIELD.text = INVALID_EMAIL
+        REGISTER_VALIDATOR.validate { (errors) -> Void in
+            XCTAssert(errors.count == 1, "Should come back with 1 error")
+        }
+    }
 }