Client Hints

Client Hints can be used as input to proactive content negotiation;
just as the Accept header allowed clients to indicate what formats
they prefer, Client Hints allow clients to indicate a list of device
and agent specific preferences.

See:
https://github.com/igrigorik/http-client-hints/blob/draft2/draft-grigorik-http-client-hints-01.txt

Patched from https://codereview.chromium.org/23654014/, which was
patched from https://codereview.chromium.org/11970002

BUG=170388
CONTRIBUTOR=yoav@yoav.ws

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=225425

Review URL: https://codereview.chromium.org/24451003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@227178 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 56 insertions, 0 deletions

diff --git a/chrome/browser/net/client_hints_unittest.cc b/chrome/browser/net/client_hints_unittest.cc
new file mode 100644
index 0000000..d64fe53
--- /dev/null
+++ b/chrome/browser/net/client_hints_unittest.cc
@@ -0,0 +1,56 @@
+// Copyright 2013 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 "chrome/browser/net/client_hints.h"
+
+#include <locale.h>
+
+#include "base/logging.h"
+#if defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_IOS)
+#include "base/test/scoped_locale.h"
+#endif
+#include "testing/gtest/include/gtest/gtest.h"
+
+class ClientHintsTest : public testing::Test {
+ public:
+  void UpdateScreenInfo(float pixel_ratio) {
+    client_hints_.UpdateScreenInfo(pixel_ratio);
+  };
+
+ protected:
+  ClientHints client_hints_;
+};
+
+TEST_F(ClientHintsTest, HintsWellFormatted) {
+  UpdateScreenInfo(1.567f);
+  std::string hint = client_hints_.GetDevicePixelRatioHeader();
+  EXPECT_EQ("1.57", hint);
+}
+
+// Android and iOS do not support setLocale.
+#if defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_IOS)
+// TODO(bengr): Use ScopedLocal in Windows once it is supported.
+TEST_F(ClientHintsTest, HintsWellFormattedWithNonEnLocale) {
+  base::ScopedLocale locale("fr_FR.UTF-8");
+  UpdateScreenInfo(1.567f);
+  std::string hint = client_hints_.GetDevicePixelRatioHeader();
+  EXPECT_EQ("1.57", hint);
+}
+#endif  // defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_IOS)
+
+TEST_F(ClientHintsTest, HintsHaveNonbogusValues) {
+  UpdateScreenInfo(-1.567f);
+  std::string hint = client_hints_.GetDevicePixelRatioHeader();
+  EXPECT_EQ("", hint);
+
+  UpdateScreenInfo(1.567f);
+  hint = client_hints_.GetDevicePixelRatioHeader();
+  EXPECT_EQ("1.57", hint);
+
+  UpdateScreenInfo(0.0f);
+  hint = client_hints_.GetDevicePixelRatioHeader();
+  // Hints should be last known good values.
+  EXPECT_EQ("1.57", hint);
+}
+