feat: solution for 'Повторный экзамен #2: Сравнительный обзор 3 сущностей (Tavily)'

test/compare.test.js

@@ -0,0 +1,37 @@
+const compare = require('../src/compare');
+
+describe('compare function', () => {
+  test('returns empty array when all objects are equal', () => {
+    const a = { x: 1, y: 2 };
+    const b = { x: 1, y: 2 };
+    const c = { x: 1, y: 2 };
+    expect(compare(a, b, c)).toEqual([]);
+  });
+
+  test('detects differences in top-level keys', () => {
+    const a = { x: 1, y: 2 };
+    const b = { x: 1, y: 3 };
+    const c = { x: 1, y: 2 };
+    expect(compare(a, b, c)).toEqual([
+      { key: 'y', values: [2, 3, 2] },
+    ]);
+  });
+
+  test('detects differences in nested objects', () => {
+    const a = { a: { b: 1 } };
+    const b = { a: { b: 2 } };
+    const c = { a: { b: 1 } };
+    expect(compare(a, b, c)).toEqual([
+      { key: 'a.b', values: [1, 2, 1] },
+    ]);
+  });
+
+  test('handles missing keys', () => {
+    const a = { x: 1 };
+    const b = { x: 1, y: 2 };
+    const c = { x: 1 };
+    expect(compare(a, b, c)).toEqual([
+      { key: 'y', values: [undefined, 2, undefined] },
+    ]);
+  });
+});