[Fetch API] Appending headers of the same name should have their values

third_party/WebKit/Source/modules/fetch/FetchHeaderList.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 "modules/fetch/FetchHeaderList.h"
 
 #include "core/fetch/FetchUtils.h"
 #include "platform/network/HTTPParsers.h"
 #include "wtf/PtrUtil.h"
 #include <algorithm>
@@ skipping 12 matching lines @@
 }
 
 FetchHeaderList::FetchHeaderList() {}
 
 FetchHeaderList::~FetchHeaderList() {}
 
 void FetchHeaderList::append(const String& name, const String& value) {
   // "To append a name/value (|name|/|value|) pair to a header list (|list|),
   // append a new header whose name is |name|, byte lowercased, and value is
   // |value|, to |list|."
-  m_headerList.append(WTF::wrapUnique(new Header(name.lower(), value)));
+  if (!value.isEmpty())

[jsbell, 2016/12/16 22:29:37]

This seems incorrect - the caller (Headers::append) should validate this first.

+    m_headerList.append(WTF::wrapUnique(new Header(name.lower(), value)));
 }
 
 void FetchHeaderList::set(const String& name, const String& value) {
   // "To set a name/value (|name|/|value|) pair in a header list (|list|), run
   // these steps:
   // 1. Byte lowercase |name|.
   // 2. If there are any headers in |list| whose name is |name|, set the value
   //    of the first such header to |value| and remove the others.
   // 3. Otherwise, append a new header whose name is |name| and value is
   //    |value|, to |list|."
@@ skipping 36 matching lines @@
   for (size_t i = 0; i < m_headerList.size();) {
     if (m_headerList[i]->first == lowercasedName)
       m_headerList.remove(i);
     else
       ++i;
   }
 }
 
 bool FetchHeaderList::get(const String& name, String& result) const {
   const String lowercasedName = name.lower();
-  for (size_t i = 0; i < m_headerList.size(); ++i) {
-    if (m_headerList[i]->first == lowercasedName) {
-      result = m_headerList[i]->second;
-      return true;
+  for (const auto& header : m_headerList) {
+    DCHECK(!header->second.isEmpty());
+    if (header->first == lowercasedName) {
+      if (result.isEmpty()) {
+        result = header->second;
+      } else {
+        result.append(",");
+        result.append(header->second);
+      }
     }
   }
-  return false;
+  return !result.isEmpty();
 }
 
 void FetchHeaderList::getAll(const String& name, Vector<String>& result) const {
   const String lowercasedName = name.lower();
   result.clear();
   for (size_t i = 0; i < m_headerList.size(); ++i) {
     if (m_headerList[i]->first == lowercasedName)
       result.append(m_headerList[i]->second);
   }
 }
@@ skipping 47 matching lines @@
   return isValidHTTPToken(name);
 }
 
 bool FetchHeaderList::isValidHeaderValue(const String& value) {
   // "A value is a byte sequence that matches the field-value token production
   // and contains no 0x0A or 0x0D bytes."
   return isValidHTTPHeaderValue(value);
 }
 
 }  // namespace blink