validate status is in range

fixes #1213

fetch.js

@@ -462,6 +462,9 @@ export function Response(bodyInit, options) {
 
   this.type = 'default'
   this.status = options.status === undefined ? 200 : options.status
+  if (this.status < 200 || this.status > 599) {
+    throw new RangeError("Failed to construct 'Response': The status provided (0) is outside the range [200, 599].")
+  }
   this.ok = this.status >= 200 && this.status < 300
   this.statusText = options.statusText === undefined ? '' : '' + options.statusText
   this.headers = new Headers(options.headers)
@@ -481,7 +484,8 @@ Response.prototype.clone = function() {
 }
 
 Response.error = function() {
-  var response = new Response(null, {status: 0, statusText: ''})
+  var response = new Response(null, {status: 200, statusText: ''})
+  response.status = 0
   response.type = 'error'
   return response
 }

test/test.js

@@ -623,6 +623,21 @@ exercise.forEach(function(exerciseMode) {
           Response('{"foo":"bar"}', {headers: {'content-type': 'application/json'}})
         })
       })
+      test('status outside inclusive range 200-599 ', function() {
+        assert.throws(function() {
+          new Response('', {status: 199})
+        })
+        for (var i = 0; i < 200; i++) {
+          assert.throws(function() {
+            new Response('', {status: i})
+          })
+        }
+        for (i = 999; i > 599; i--) {
+          assert.throws(function() {
+            new Response('', {status: i})
+          })
+        }
+      })
       test('creates Headers object from raw headers', function() {
         var r = new Response('{"foo":"bar"}', {headers: {'content-type': 'application/json'}})
         assert.equal(r.headers instanceof Headers, true)