Support Using ScopedFeatureList in BrowserTest

chrome/test/base/in_process_browser_test_browsertest.cc

Index: chrome/test/base/in_process_browser_test_browsertest.cc
diff --git a/chrome/test/base/in_process_browser_test_browsertest.cc b/chrome/test/base/in_process_browser_test_browsertest.cc
index 22953ce9dade2ffb78d3bdfd66fd90ff02d407e6..5519993a8ddf08714f7ff2beccb5c7e18651fa6e 100644
--- a/chrome/test/base/in_process_browser_test_browsertest.cc
+++ b/chrome/test/base/in_process_browser_test_browsertest.cc
@@ -5,9 +5,12 @@
 #include <stddef.h>
 #include <string.h>
 
+#include "base/command_line.h"
 #include "base/files/file_util.h"
 #include "base/macros.h"
 #include "base/path_service.h"
+#include "base/strings/string_split.h"
+#include "base/test/scoped_feature_list.h"
 #include "chrome/browser/after_startup_task_utils.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
@@ -17,6 +20,7 @@
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_observer.h"
+#include "content/public/common/content_switches.h"
 #include "net/base/filename_util.h"
 #include "net/base/net_errors.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -150,4 +154,45 @@ IN_PROC_BROWSER_TEST_F(
   EXPECT_NE("", test_result);
 }
 
+const base::Feature kTestFeatureForBrowserTest{
+    "TestFeatureForBrowserTest", base::FEATURE_DISABLED_BY_DEFAULT};
+
+class BrowserTestScopedFeatureListTest : public InProcessBrowserTest {
+ public:
+  void SetUp() override {
+    std::string disabled_features;
+    base::FeatureList::GetInstance()->GetFeatureOverrides(&enabled_features_,
+                                                          &disabled_features);
+    scoped_feature_list_.InitAndEnableFeature(kTestFeatureForBrowserTest);
+    InProcessBrowserTest::SetUp();
+  }
+
+  std::string enabled_features_;
+
+ private:
+  base::test::ScopedFeatureList scoped_feature_list_;
+};
+
+IN_PROC_BROWSER_TEST_F(BrowserTestScopedFeatureListTest, FeatureListTest) {
+  std::string enabled_features0;
+  std::string disabled_features0;
+
+  base::FeatureList::GetInstance()->GetFeatureOverrides(&enabled_features0,
+                                                        &disabled_features0);
+
+  base::StringPiece enabled_features = enabled_features0;
+
+  // Ensure we repected the features from command line.
+  std::vector<base::StringPiece> original_enabled_features =
+      base::SplitStringPiece(enabled_features_, ",", base::TRIM_WHITESPACE,
+                             base::SPLIT_WANT_NONEMPTY);

[Ilya Sherman, 2017/06/09 20:19:28]

Again, if this test doesn't know what features were enabled on the command-line,
why is it testing them?  It's plausible to me that there simply aren't any
enabled features, and this is a no-op.  If you want to test this behavior,
please test it in a way where you are controlling at least one feature that is
enabled.

[chaopeng, 2017/06/13 04:16:32]

These two tests seems useless, maybe I should just remove it.

+
+  for (base::StringPiece enabled_feature : original_enabled_features) {
+    EXPECT_NE(enabled_features.find(enabled_feature), base::StringPiece::npos);
+  }
+
+  // Ensure kTestFeatureForBrowserTest enabled.
+  EXPECT_TRUE(base::FeatureList::IsEnabled(kTestFeatureForBrowserTest));
+}
+
 }  // namespace