Merge pull request #704 from streamich/fix-array-check

Improve deep equals array checks

Author: streamich

src/json-equal/__bench__/bench.deepEqual.ts

@@ -1,14 +1,14 @@
+// npx ts-node src/json-equal/__bench__/bench.deepEqual.ts
+
 /* tslint:disable no-console */
 
 import * as Benchmark from 'benchmark';
 import {deepEqual as deepEqualV1} from '../deepEqual/v1';
 import {deepEqual as deepEqualV2} from '../deepEqual/v2';
 import {deepEqual as deepEqualV3} from '../deepEqual/v3';
-import {deepEqual as deepEqualV4} from '../deepEqual/v3';
+import {deepEqual as deepEqualV4} from '../deepEqual/v4';
+import {deepEqual as deepEqualV5} from '../deepEqual/v5';
 import {$$deepEqual} from '../$$deepEqual';
-const fastDeepEqual = require('fast-deep-equal/es6');
-const fastEquals = require('fast-equals').deepEqual;
-const lodashIsEqual = require('lodash').isEqual;
 
 const json1 = {
   foo: 'bar',
@@ -39,14 +39,8 @@ suite
   .add(`json-joy/json-equal (v4)`, () => {
     deepEqualV4(json1, json2);
   })
-  .add(`fast-deep-equal`, () => {
-    fastDeepEqual(json1, json2);
-  })
-  .add(`fast-equals`, () => {
-    fastEquals(json1, json2);
-  })
-  .add(`lodash.isEqual`, () => {
-    lodashIsEqual(json1, json2);
+  .add(`json-joy/json-equal (v5)`, () => {
+    deepEqualV5(json1, json2);
   })
   .add(`json-joy/json-equal/$$deepEqual`, () => {
     equalGenerated1(json2);

src/json-equal/deepEqual/__tests__/deepEqual.fuzzing.spec.ts

@@ -9,8 +9,14 @@ for (let i = 0; i < 100; i++) {
     const res1 = deepEqual(json1, json1);
     const res2 = deepEqual(json1, json2);
     const res3 = deepEqual(json2, json1);
-    expect(res1).toBe(true);
-    expect(res2).toBe(true);
-    expect(res3).toBe(true);
+    try {
+      expect(res1).toBe(true);
+      expect(res2).toBe(true);
+      expect(res3).toBe(true);
+    } catch (error) {
+      // tslint:disable-next-line no-console
+      console.log({json1, json2});
+      throw error;
+    }
   });
 }

src/json-equal/deepEqual/__tests__/runDeepEqualTestSuite.ts

@@ -6,9 +6,13 @@ export const runDeepEqualTestSuite = (deepEqual: (a: unknown, b: unknown) => boo
       for (const t of s.tests) {
         test(t.description, () => {
           const res1 = deepEqual(t.value1, t.value2);
-          const res2 = deepEqual(t.value1, t.value2);
-          expect(res1).toBe(t.equal);
-          expect(res2).toBe(t.equal);
+          const res2 = deepEqual(t.value2, t.value1);
+          try {
+            expect(res1).toBe(t.equal);
+            expect(res2).toBe(t.equal);
+          } catch (error) {
+            throw error;
+          }
         });
       }
     });

src/json-equal/deepEqual/index.ts

@@ -1 +1 @@
-export * from './v1';
+export * from './v5';

src/json-equal/deepEqual/v5.ts

@@ -0,0 +1,31 @@
+const isArray = Array.isArray;
+
+export const deepEqual = (a: unknown, b: unknown): boolean => {
+  // Primitives
+  if (a === b) return true;
+
+  // Arrays
+  let length, i, keys;
+  if (isArray(a)) {
+    if (!isArray(b)) return false;
+    length = a.length;
+    if (length !== (b as Array<unknown>).length) return false;
+    for (i = length; i-- !== 0; ) if (!deepEqual(a[i], (b as Array<unknown>)[i])) return false;
+    return true;
+  }
+
+  // Objects
+  if (a && b && typeof a === 'object' && typeof b === 'object') {
+    keys = Object.keys(a);
+    length = keys.length;
+    if (length !== Object.keys(b).length) return false;
+    if (isArray(b)) return false;
+    for (i = length; i-- !== 0; ) {
+      const key = keys[i];
+      if (!deepEqual((a as Record<string, unknown>)[key], (b as Record<string, unknown>)[key])) return false;
+    }
+    return true;
+  }
+
+  return false;
+};