Add variations params api to get params from features.

components/variations/variations_associated_data_unittest.cc

Index: components/variations/variations_associated_data_unittest.cc
diff --git a/components/variations/variations_associated_data_unittest.cc b/components/variations/variations_associated_data_unittest.cc
index 470490dacdd3c3e4bf402b691b39294a577b0a26..5ab23011ad52be63ee5f2143af8479e50450bb3a 100644
--- a/components/variations/variations_associated_data_unittest.cc
+++ b/components/variations/variations_associated_data_unittest.cc
@@ -4,6 +4,7 @@
 
 #include "components/variations/variations_associated_data.h"
 
+#include "base/feature_list.h"
 #include "base/macros.h"
 #include "base/metrics/field_trial.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -33,6 +34,16 @@ scoped_refptr<base::FieldTrial> CreateFieldTrial(
       base::FieldTrial::SESSION_RANDOMIZED, default_group_number);
 }
 
+void CreateFeatureWithTrial(const base::Feature& feature,
+                            base::FeatureList::OverrideState override_state,
+                            scoped_refptr<base::FieldTrial> trial) {

[Alexei Svitkine (slow), 2016/05/03 17:04:25]

Nit: Just pass by FieldTrial*.

[jwd, 2016/05/03 20:12:27]

Done.

+  base::FeatureList::ClearInstanceForTesting();
+  std::unique_ptr<base::FeatureList> feature_list(new base::FeatureList);
+  feature_list->RegisterFieldTrialOverride(feature.name, override_state,
+                                           trial.get());
+  base::FeatureList::SetInstance(std::move(feature_list));
+}
+
 }  // namespace
 
 class VariationsAssociatedDataTest : public ::testing::Test {
@@ -346,4 +357,81 @@ TEST_F(VariationsAssociatedDataTest, GetVariationParamValue_ActivatesTrial) {
   ASSERT_TRUE(base::FieldTrialList::IsTrialActive(kTrialName));
 }
 
+TEST_F(VariationsAssociatedDataTest, GetVariationParamsByFeature) {
+  const std::string kTrialName = "GetVariationParamsByFeature";
+
+  std::map<std::string, std::string> params;
+  params["x"] = "1";
+  variations::AssociateVariationParams(kTrialName, "A", params);
+  scoped_refptr<base::FieldTrial> trial(
+      CreateFieldTrial(kTrialName, 100, "A", NULL));
+
+  const base::Feature kFeature{"TestFeature",
+                               base::FEATURE_DISABLED_BY_DEFAULT};
+
+  CreateFeatureWithTrial(kFeature, base::FeatureList::OVERRIDE_ENABLE_FEATURE,
+                         trial);
+
+  std::map<std::string, std::string> actualParams;
+  EXPECT_TRUE(GetVariationParamsByFeature(kFeature, &actualParams));
+  EXPECT_EQ(params, actualParams);
+}
+
+TEST_F(VariationsAssociatedDataTest, GetVariationParamValueByFeature) {
+  const std::string kTrialName = "GetVariationParamsByFeature";
+
+  std::map<std::string, std::string> params;
+  params["x"] = "1";
+  variations::AssociateVariationParams(kTrialName, "A", params);
+  scoped_refptr<base::FieldTrial> trial(
+      CreateFieldTrial(kTrialName, 100, "A", NULL));
+
+  const base::Feature kFeature{"TestFeature",
+                               base::FEATURE_DISABLED_BY_DEFAULT};
+
+  CreateFeatureWithTrial(kFeature, base::FeatureList::OVERRIDE_ENABLE_FEATURE,
+                         trial);
+
+  std::map<std::string, std::string> actualParams;
+  EXPECT_EQ(params["x"], GetVariationParamValueByFeature(kFeature, "x"));
+}
+
+TEST_F(VariationsAssociatedDataTest, GetVariationParamsByFeature_Disable) {
+  const std::string kTrialName = "GetVariationParamsByFeature";
+
+  std::map<std::string, std::string> params;
+  params["x"] = "1";
+  variations::AssociateVariationParams(kTrialName, "A", params);
+  scoped_refptr<base::FieldTrial> trial(
+      CreateFieldTrial(kTrialName, 100, "A", NULL));
+
+  const base::Feature kFeature{"TestFeature",
+                               base::FEATURE_DISABLED_BY_DEFAULT};
+
+  CreateFeatureWithTrial(kFeature, base::FeatureList::OVERRIDE_DISABLE_FEATURE,
+                         trial);
+
+  std::map<std::string, std::string> actualParams;
+  EXPECT_FALSE(GetVariationParamsByFeature(kFeature, &actualParams));
+}
+
+TEST_F(VariationsAssociatedDataTest, GetVariationParamValueByFeature_Disable) {
+  const std::string kTrialName = "GetVariationParamsByFeature";
+
+  std::map<std::string, std::string> params;
+  params["x"] = "1";
+  variations::AssociateVariationParams(kTrialName, "A", params);
+  scoped_refptr<base::FieldTrial> trial(
+      CreateFieldTrial(kTrialName, 100, "A", NULL));
+
+  const base::Feature kFeature{"TestFeature",

[Alexei Svitkine (slow), 2016/05/03 17:04:25]

Nit: Maybe move this to the top of the function below kTrialName so that the
constants are together.

[jwd, 2016/05/03 20:12:27]

Done.

+                               base::FEATURE_DISABLED_BY_DEFAULT};
+
+  CreateFeatureWithTrial(kFeature, base::FeatureList::OVERRIDE_DISABLE_FEATURE,
+                         trial);
+
+  std::map<std::string, std::string> actualParams;
+  EXPECT_EQ(std::string(), GetVariationParamValueByFeature(kFeature, "x"));
+}
+
 }  // namespace variations