testing 101

Signed-off-by: Kenneth Obsequio <k80308392@gmail.com>

tests/utils/response.test.js

@@ -0,0 +1,92 @@
+'use strict';
+
+const R = require('../../utils/response.util');
+
+function makeRes() {
+  const res = {
+    _status: null,
+    _body: null,
+    status(code) { this._status = code; return this; },
+    json(body)   { this._body  = body;  return this; },
+  };
+  return res;
+}
+
+// ── R.success ─────────────────────────────────────────────────────────────────
+
+describe('R.success()', () => {
+  test('default status is 200', () => {
+    const res = makeRes();
+    R.success(res, 'OK');
+    expect(res._status).toBe(200);
+  });
+
+  test('envelope shape: status=success, message, data', () => {
+    const res = makeRes();
+    R.success(res, 'Created', { id: 1 }, 201);
+    expect(res._body).toEqual({ status: 'success', message: 'Created', data: { id: 1 } });
+  });
+
+  test('custom status code is used', () => {
+    const res = makeRes();
+    R.success(res, 'Created', null, 201);
+    expect(res._status).toBe(201);
+  });
+
+  test('data is null when omitted', () => {
+    const res = makeRes();
+    R.success(res, 'OK');
+    expect(res._body.data).toBeNull();
+  });
+});
+
+// ── R.error ───────────────────────────────────────────────────────────────────
+
+describe('R.error()', () => {
+  test('default status is 500', () => {
+    const res = makeRes();
+    R.error(res, 'Something broke');
+    expect(res._status).toBe(500);
+  });
+
+  test('envelope shape: status=error, message', () => {
+    const res = makeRes();
+    R.error(res, 'Not found', 404);
+    expect(res._body).toMatchObject({ status: 'error', message: 'Not found' });
+    expect(res._status).toBe(404);
+  });
+
+  test('errors field is absent when not provided', () => {
+    const res = makeRes();
+    R.error(res, 'Bad request', 400);
+    expect(res._body).not.toHaveProperty('errors');
+  });
+
+  test('errors field is included when provided', () => {
+    const res  = makeRes();
+    const errs = [{ field: 'email', msg: 'Invalid' }];
+    R.error(res, 'Validation failed', 422, errs);
+    expect(res._body.errors).toEqual(errs);
+  });
+});
+
+// ── R.validationError ─────────────────────────────────────────────────────────
+
+describe('R.validationError()', () => {
+  test('status is always 422', () => {
+    const res = makeRes();
+    R.validationError(res, []);
+    expect(res._status).toBe(422);
+  });
+
+  test('envelope shape: status=error, message=Validation failed, errors', () => {
+    const res  = makeRes();
+    const errs = [{ field: 'name', msg: 'Required' }];
+    R.validationError(res, errs);
+    expect(res._body).toEqual({
+      status:  'error',
+      message: 'Validation failed',
+      errors:  errs,
+    });
+  });
+});