imp: work on store, refactor, improve todoapp

tests/utils.test.ts

@@ -4,7 +4,8 @@ import {
   idGenerator,
   memoize,
   debounce,
-  findInTree
+  findInTree,
+  shallowEqual
 } from "../src/utils";
 
 describe("escape", () => {
@@ -91,3 +92,14 @@ describe("findInTree", () => {
     expect(match2).toBe(null);
   });
 });
+
+describe("shallowEqual", () => {
+  test("simple comparisons", () => {
+    const obj1 = {};
+    expect(shallowEqual(obj1, obj1)).toBe(true);
+    expect(shallowEqual({}, {})).toBe(true);
+    expect(shallowEqual({ a: 1 }, {})).toBe(false);
+    expect(shallowEqual({ a: 1 }, { a: 1 })).toBe(true);
+    expect(shallowEqual({ a: 1 }, ["a"])).toBe(false);
+  });
+});