1 // Copyright 2022 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "chrome/browser/chrome_browser_field_trials.h"
9 #include "base/feature_list.h"
10 #include "components/prefs/testing_pref_service.h"
11 #include "components/ukm/ukm_recorder_impl.h"
12 #include "testing/gtest/include/gtest/gtest.h"
14 #if BUILDFLAG(IS_WIN) || BUILDFLAG(IS_ANDROID)
15 TEST(ChromeBrowserFieldTrialsTest, SamplingTrials) {
16 TestingPrefServiceSimple local_state;
17 ChromeBrowserFieldTrials chrome_browser_field_trials(&local_state);
19 const char kSamplingTrialName[] = "MetricsAndCrashSampling";
20 #if BUILDFLAG(IS_ANDROID)
21 const char kPostFREFixSamplingTrialName[] =
22 "PostFREFixMetricsAndCrashSampling";
23 #endif // BUILDFLAG(IS_ANDROID)
24 const char kUkmSamplingTrialName[] = "UkmSamplingRate";
26 // Verify that initially, sampling trials do not exist.
27 EXPECT_FALSE(base::FieldTrialList::TrialExists(kSamplingTrialName));
28 #if BUILDFLAG(IS_ANDROID)
29 EXPECT_FALSE(base::FieldTrialList::TrialExists(kPostFREFixSamplingTrialName));
30 #endif // BUILDFLAG(IS_ANDROID)
31 EXPECT_FALSE(base::FieldTrialList::TrialExists(kUkmSamplingTrialName));
33 // Call SetUpClientSideFieldTrials(), which should create fallback
34 // sampling trials since they do not exist yet.
35 variations::EntropyProviders entropy_providers("client_id", {0, 8000});
36 auto feature_list = std::make_unique<base::FeatureList>();
37 chrome_browser_field_trials.SetUpClientSideFieldTrials(
38 /*has_seed=*/false, entropy_providers, feature_list.get());
40 // Verify that the sampling trials were created.
41 EXPECT_TRUE(base::FieldTrialList::TrialExists(kSamplingTrialName));
42 #if BUILDFLAG(IS_ANDROID)
43 EXPECT_TRUE(base::FieldTrialList::TrialExists(kPostFREFixSamplingTrialName));
44 #endif // BUILDFLAG(IS_ANDROID)
45 EXPECT_TRUE(base::FieldTrialList::TrialExists(kUkmSamplingTrialName));
47 // Call SetUpClientSideFieldTrials() again. This should be a no-op,
48 // since the sampling trials already exist. If the trials are created again,
49 // a CHECK will be triggered and this will crash.
50 chrome_browser_field_trials.SetUpClientSideFieldTrials(
51 /*has_seed=*/false, entropy_providers, feature_list.get());
53 #endif // BUILDFLAG(IS_WIN) || BUILDFLAG(IS_ANDROID)