Fix setting multiple cookies as multiple 'Set-Cookie' headers. (fix f…

…astify#1358)

lib/reply.js

@@ -159,11 +159,14 @@ Reply.prototype.header = function (key, value) {
 
   if (this[kReplyHeaders][_key] && _key === 'set-cookie') {
     // https://tools.ietf.org/html/rfc7230#section-3.2.2
-    var _cookies = this[kReplyHeaders][_key]
-    if (typeof _cookies === 'string') {
-      _cookies = [_cookies]
+    if (typeof this[kReplyHeaders][_key] === 'string') {
+      this[kReplyHeaders][_key] = [this[kReplyHeaders][_key]]
+    }
+    if (Array.isArray(value)) {
+      Array.prototype.push.apply(this[kReplyHeaders][_key], value)
+    } else {
+      this[kReplyHeaders][_key].push(value)
     }
-    this[kReplyHeaders][_key] = _cookies.concat(value)
   } else {
     this[kReplyHeaders][_key] = value
   }

test/internals/reply.test.js

@@ -905,7 +905,7 @@ test('.status() is an alias for .code()', t => {
 })
 
 test('reply.header setting multiple cookies as multiple Set-Cookie headers', t => {
-  t.plan(4)
+  t.plan(7)
 
   const fastify = require('../../')()
 
@@ -914,7 +914,7 @@ test('reply.header setting multiple cookies as multiple Set-Cookie headers', t =
       .header('set-cookie', 'one')
       .header('set-cookie', 'two')
       .header('set-cookie', 'three')
-      .header('set-cookie', 'four')
+      .header('set-cookie', ['four', 'five', 'six'])
       .send({})
   })
 
@@ -928,7 +928,13 @@ test('reply.header setting multiple cookies as multiple Set-Cookie headers', t =
     }, (err, response, body) => {
       t.error(err)
       t.ok(response.headers['set-cookie'])
-      t.strictDeepEqual(response.headers['set-cookie'], ['one', 'two', 'three', 'four'])
+      t.strictDeepEqual(response.headers['set-cookie'], ['one', 'two', 'three', 'four', 'five', 'six'])
     })
   })
+
+  fastify.inject('/headers', (error, response) => {
+    t.error(error)
+    t.ok(response.headers['set-cookie'])
+    t.strictDeepEqual(response.headers['set-cookie'], ['one', 'two', 'three', 'four', 'five', 'six'])
+  })
 })