refactor: split brokerage operations repository and cursor codec (WealthLedger/backend#167) (#190)

src/modules/investments/operations/application/local-operations-cursor.codec.spec.ts

@@ -0,0 +1,23 @@
+import { decode, encode } from './local-operations-cursor.codec';
+
+const secret = 'secret';
+const cursor = {
+  accountId: 'account',
+  at: '2026-01-01T00:00:00.000Z',
+  binding: 'owner-filter-binding',
+  id: 'operation',
+  movingEnd: false,
+  to: '2026-02-01T00:00:00.000Z',
+};
+
+describe('local operations cursor', () => {
+  it('roundtrips the opaque cursor, including its owner and filter binding', () => {
+    expect(decode(encode(cursor, secret), secret)).toEqual(cursor);
+  });
+
+  it('rejects a tampered cursor and a cursor signed with a different key', () => {
+    const encoded = encode(cursor, secret);
+    expect(() => decode(`${encoded}x`, secret)).toThrow();
+    expect(() => decode(encoded, 'different-secret')).toThrow();
+  });
+});