Make sure to include extraneous properties in the result value, when allowed

index.js

@@ -54,9 +54,10 @@ module.exports = function hasShape(rules) {
 			let errors = [];
 			let newObject = {};
 
-			for (let [ key, rule ] of Object.entries(rules)) {
+			for (let [ key, value ] of Object.entries(object)) {
-				let value = object[key];
+				let rule = rules[key];
 
+				if (rule != null) {
 					let { errors: keyErrors, newValue } = applyValidators(value, rule);
 
 					let annotatedErrors = annotateErrors({
@@ -66,6 +67,10 @@ module.exports = function hasShape(rules) {
 
 					errors.push(... annotatedErrors);
 					newObject[key] = newValue;
+				} else {
+					// Extraneous property
+					newObject[key] = value;
+				}
 			}
 
 			return validationResult({