Merge pull request #1 from sverrejoh/master

Fixed issue with `undefined` values

Author: podefr

index.js

@@ -54,7 +54,7 @@ module.exports = function shallowDiff(base, compared) {
    loop(compared, function (value, idx) {
 
        // To get the added
-       if (typeof base[idx] == "undefined") {
+     if (!(idx in base)) {
            added.push(idx);
 
        // The updated
@@ -72,7 +72,7 @@ module.exports = function shallowDiff(base, compared) {
    loop(base, function (value, idx) {
 
       // To get the deleted
-      if (typeof compared[idx] == "undefined") {
+      if (!(idx in compared)) {
           deleted.push(idx);
       }
    });

test/shallow-diff.spec.js

@@ -34,6 +34,12 @@ describe("shallow-diff", function () {
 		expect(Array.isArray(result.deleted)).to.be.true;
 	});
 
+        it("should should handle `undefined` values", function() {
+          var result = sut({a: undefined}, {a: undefined});
+          expect(result.added.length).to.equal(0);
+          expect(result.deleted.length).to.equal(0);
+        });
+
 	describe("with an array", function () {
 		var initialArray = ["a", "b", "c", "d"],
 			finalArray = ["a", "d", "e"];