Refine tests for mergeSort

utilities/javascript/deepEqual.js

@@ -0,0 +1,38 @@
+function deepEqual(val1, val2) {
+    if (typeof val1 !== typeof val2) {
+        return false;
+    }
+
+    // Array comparison.
+    if (Array.isArray(val1) && Array.isArray(val2)) {
+        if (val1.length !== val2.length) {
+            return false;
+        }
+        for (let i = 0; i < val1.length; i++) {
+            if (!deepEqual(val1[i], val2[i])) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    // Object comparison.
+    if (typeof val1 === 'object' && typeof val2 === 'object') {
+        const keys1 = Object.keys(val1);
+        const keys2 = Object.keys(val2);
+        if (keys1.length !== keys2.length) {
+            return false;
+        }
+        for (let i = 0; i < keys1.length; i++) {
+            if (!deepEqual(val1[keys1[i]], val2[keys2[i]])) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    // Primitive comparison.
+    return val1 === val2;
+}
+
+module.exports = deepEqual;