feat(core): Add new matchers and improve negation messaging

test/test.expectAny.ts

@@ -0,0 +1,38 @@
+import { tap } from '@push.rocks/tapbundle';
+import * as smartexpect from '../dist_ts/index.js';
+
+tap.test('expect.any and expect.anything basic usage', async () => {
+  const obj = { a: 1, b: 'two', d: new Date() };
+  // Using expect.any to match types
+  smartexpect.expect(obj).object.toMatchObject({
+    a: smartexpect.expect.any(Number),
+    b: smartexpect.expect.any(String),
+    d: smartexpect.expect.any(Date),
+  });
+  // Using expect.anything to match any defined value
+  smartexpect.expect(obj).object.toMatchObject({
+    a: smartexpect.expect.anything(),
+    b: smartexpect.expect.anything(),
+    d: smartexpect.expect.anything(),
+  });
+});
+
+tap.test('expect.any mismatch and anything null/undefined rejection', async () => {
+  const obj = { a: 1, b: null };
+  // Mismatch for expect.any
+  try {
+    smartexpect.expect(obj).object.toMatchObject({ a: smartexpect.expect.any(String) });
+    throw new Error('Expected mismatch for expect.any did not throw');
+  } catch (err) {
+    // success: thrown on mismatch
+  }
+  // anything should reject null or undefined
+  try {
+    smartexpect.expect(obj).object.toMatchObject({ b: smartexpect.expect.anything() });
+    throw new Error('Expected anything() to reject null or undefined');
+  } catch (err) {
+    // success: thrown on null
+  }
+});
+
+export default tap.start();