Fix cookie case sensitive name

lib/cookies/assertion.js

@@ -212,7 +212,8 @@ module.exports = function (secret, asserts) {
         return;
       }
 
-      const key = part.substr(0, equalsIndex).trim().toLowerCase();
+      const rawKey = part.substr(0, equalsIndex).trim();
+      const key = i > 0 ? rawKey.toLowerCase() : rawKey;
       // only assign once
       if (typeof cookie[key] !== 'undefined') return;
 
@@ -286,7 +287,6 @@ module.exports = function (secret, asserts) {
       assertions.push(function (req, res) {
         // get expectation cookie
         const cookie = Assertion.find(expect.name, res.cookies);
-
         if (assert && !cookie) throw new Error('expected: ' + expect.name + ' cookie to be set');
 
         if (assert) assertHasProperties(cookie.options, expect.options);

test/cookies.js

@@ -1281,4 +1281,26 @@ describe('cookie', function () {
         });
     });
   });
+
+  describe('Cookie name case is respected', function () {
+    it('asserts true if cookie name contains capital letters', function () {
+      const app = express();
+      app.get('/users', function(req, res) {
+        res.cookie('Alpha', 'one', { domain: 'domain.com', path: '/', httpOnly: true });
+        res.send(200, { name: 'tobi' });
+      });
+      request(app)
+        .get('/users')
+        .expect('Content-Type', /json/)
+        .expect('Content-Length', '15')
+        .expect(200)
+        // assert 'Alpha' cookie is set with domain, path, and httpOnly options
+        .expect(cookies.set({ name: 'Alpha', options: ['domain', 'path', 'httponly'] }))
+        .end(function(err, res) {
+          if (err) {
+            throw err;
+          }
+        });
+    });
+  });
 });