improve deepEqual to handle Set & Map

Author: Regaddi

src/lib/deepEqual.ts

@@ -30,6 +30,16 @@ export function deepEqual(a: any, b: any): boolean {
     return a.source === b.source && a.flags === b.flags;
   }
 
+  // Handle special case for Set
+  if (a instanceof Set && b instanceof Set) {
+    return deepEqual([...a], [...b]);
+  }
+
+  // Handle special case for Map
+  if (a instanceof Map && b instanceof Map) {
+    return deepEqual(Object.fromEntries(a), Object.fromEntries(b));
+  }
+
   // If a or b are not objects or null, they can't be deeply equal
   if (
     typeof a !== 'object' ||

test/lib/deepEqual.test.ts

@@ -118,6 +118,29 @@ describe('deepEqual', () => {
     });
   });
 
+  describe('Map', () => {
+    it.each`
+      a                 | b                      | expected
+      ${new Set()}      | ${new Set()}           | ${true}
+      ${new Set(['a'])} | ${new Set(['b'])}      | ${false}
+      ${new Set(['a'])} | ${new Set(['a', 'b'])} | ${false}
+      ${new Set(['a'])} | ${['a']}               | ${false}
+    `('returns $expected for a: $a and b: $b', ({ a, b, expected }) => {
+      expect(deepEqual(a, b)).toBe(expected);
+    });
+  });
+
+  describe('Map', () => {
+    it.each`
+      a                      | b                                | expected
+      ${new Map()}           | ${new Map()}                     | ${true}
+      ${new Map([['a', 1]])} | ${new Map([['b', 1]])}           | ${false}
+      ${new Map([['a', 1]])} | ${new Map([['a', 1], ['b', 1]])} | ${false}
+    `('returns $expected for a: $a and b: $b', ({ a, b, expected }) => {
+      expect(deepEqual(a, b)).toBe(expected);
+    });
+  });
+
   describe('Functions', () => {
     const funcA = () => 'test';
     const funcB = () => 'test';