*

coding_interviews/frontend/js-coding-questions/deep-equals/deep-equals.js

@@ -0,0 +1,70 @@
+function deepEquals(valueOne, valueTwo) {
+  const hasSameType = typeof valueOne === typeof valueTwo;
+  const areEqual = valueOne === valueTwo;
+  const areNaN = Number.isNaN(valueOne) && Number.isNaN(valueTwo);
+
+  if (hasSameType && (areEqual || areNaN)) {
+    return true;
+  }
+
+  if (
+    valueOne === null ||
+    valueTwo === null ||
+    valueOne === undefined ||
+    valueTwo === undefined ||
+    (hasSameType && !areEqual)
+  ) {
+    return false;
+  }
+
+  if (Array.isArray(valueOne) && Array.isArray(valueTwo)) {
+    if (valueOne.length !== valueTwo.length) {
+      return false;
+    }
+
+    for (let index = 0; index < valueOne.length; index++) {
+      if (!deepEquals(valueOne[index], valueTwo[index])) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+
+  for (let key of Object.keys(valueOne)) {
+    if (
+      !(
+        valueTwo.hasOwnProperty(key) && deepEquals(valueOne[key], valueTwo[key])
+      )
+    ) {
+      return false;
+    }
+  }
+
+  for (let key of Object.keys(valueTwo)) {
+    if (
+      !(
+        valueOne.hasOwnProperty(key) && deepEquals(valueOne[key], valueTwo[key])
+      )
+    ) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+console.log(deepEquals(null, [1])); // false
+console.log(deepEquals([1], null)); // false
+console.log(deepEquals(undefined, [1])); // false
+console.log(deepEquals([1], undefined)); // false
+console.log(deepEquals([0], [1])); // false
+console.log(deepEquals([0, 1, 2], [4, 5, 6])); // false
+console.log(deepEquals([0, 'abc', 2], [0, 'abc', '2'])); // false
+console.log(deepEquals([0, 'abc', '2'], [0, 'abc', 2])); // false
+console.log(deepEquals([null, null, true], [null, undefined, true])); // false
+console.log(deepEquals([null, undefined, true], [null, null, true])); // false
+console.log(deepEquals({}, {})); // true
+console.log(deepEquals({ a: 123 }, { a: '123' })); // false
+console.log(deepEquals({ 1: 1, 2: 2, 3: 3 }, { 1: 1, 2: 2, 3: 3 })); // true
+console.log(deepEquals({ 1: 1, 2: 2, 3: 3 }, { 2: 2, 1: 1, 3: 3 })); // true