Introduce "navigate" mode in Requests

third_party/WebKit/Source/modules/fetch/Request.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "modules/fetch/Request.h"
 
 #include "bindings/core/v8/Dictionary.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExecutionContext.h"
@@ skipping 104 matching lines @@
         // TypeError."
         // "4. Set |request|'s url to |parsedURL|."
         request->setURL(parsedURL);
         // "5. Set |fallbackMode| to CORS."
         // "6. Set |fallbackCredentials| to omit."
         // We don't use fallback values. We set these flags directly in below.
     }
 
     //   14. If any of |init|'s members are present, set |request|'s referrer
     // to client, and |request|'s referrer policy to the empty string.
     //   => RequestInit::RequestInit.

[hiroshige, 2015/10/15 06:37:03]

The following check should be placed here.
https://fetch.spec.whatwg.org/#dom-request
Also, adding a test for Request(req, {...}) where req.mode == 'navigate' is
preferrable, but I'm not sure we can write such a test.
This predicate corresponds to |RequestInit.isReferrerSet|.

In the draft patch set of the CL that introduced |isReferrerSet|,
|isReferrerSet| was |RequestInit.areAnyMembersSet|.
https://codereview.chromium.org/1291073004/diff2/460001:560001/Source/modules...
This predicate was used only for referrer setting at that time, but now it is
also used for rejecting navigate mode.
How about renaming it again to |RequestInit.areAnyMembersSet| and using it here?
yhirano@, how do you think? Doesn't this conflict your intention of renaming
|areAnyMemberSet| to |isReferrerSet|?

[yhirano, 2015/10/15 07:00:08]

There is no problem, but adding some comments here would be helpful because
there is a small difference between what the spec says and what we do while the
result is same, and renaming the variable may cause some confusion without
further explanation.

[shiva.jm, 2015/10/16 06:30:44]

Done.

[shiva.jm, 2015/10/16 06:30:44]

Done.

     //   15. If |init|'s referrer member is present, run these substeps:
     // Note that JS null and undefined are encoded as an empty string and thus
     // a null string means referrer member is not set.
     //   16. If |init|'s referrerPolicy member is present, set |request|'s
     // referrer policy to it.
     if (init.isReferrerSet) {
         // 1. Let |referrer| be |init|'s referrer member.
         if (init.referrer.referrer.isEmpty()) {
             // 2. if |referrer| is the empty string, set |request|'s referrer to
             // "no-referrer" and terminate these substeps.
@@ skipping 19 matching lines @@
                 return nullptr;
             } else {
                 // 7. Set |request|'s referrer to |parsedReferrer|.
                 request->setReferrerString(AtomicString(parsedReferrer.string()));
             }
         }
         request->setReferrerPolicy(init.referrer.referrerPolicy);
     }
 
 
-    // "17. Let |mode| be |init|'s mode member if it is present, and
+    // "16. Let |mode| be |init|'s mode member if it is present, and
     // |fallbackMode| otherwise."
+    // "17.If mode is "navigate", throw a TypeError.
     // "18. If |mode| is non-null, set |request|'s mode to |mode|."
+    if (init.mode == "navigate") {
+        exceptionState.throwTypeError("Cannot construct a Request with a Request mode as navigate.");
+        return nullptr;
+    }
     if (init.mode == "same-origin") {
         request->setMode(WebURLRequest::FetchRequestModeSameOrigin);
     } else if (init.mode == "no-cors") {
         request->setMode(WebURLRequest::FetchRequestModeNoCORS);
     } else if (init.mode == "cors") {
         request->setMode(WebURLRequest::FetchRequestModeCORS);
     } else {
         if (!inputRequest)
             request->setMode(WebURLRequest::FetchRequestModeCORS);
     }
@@ skipping 312 matching lines @@
     // "The mode attribute's getter must return the value corresponding to the
     // first matching statement, switching on request's mode:"
     switch (m_request->mode()) {
     case WebURLRequest::FetchRequestModeSameOrigin:
         return "same-origin";
     case WebURLRequest::FetchRequestModeNoCORS:
         return "no-cors";
     case WebURLRequest::FetchRequestModeCORS:
     case WebURLRequest::FetchRequestModeCORSWithForcedPreflight:
         return "cors";
+    case WebURLRequest::FetchRequestModeNavigate:
+        return "navigate";
     }
     ASSERT_NOT_REACHED();
     return "";
 }
 
 String Request::credentials() const
 {
     // "The credentials attribute's getter must return the value corresponding
     // to the first matching statement, switching on request's credentials
     // mode:"
@@ skipping 79 matching lines @@
 }
 
 DEFINE_TRACE(Request)
 {
     Body::trace(visitor);
     visitor->trace(m_request);
     visitor->trace(m_headers);
 }
 
 } // namespace blink