Add scoped class for overriding field trials.
To be used in tests that depend on specific field-trial settings without
overwriting the command-line flag for overriding field trials.
BUG=webrtc:4820
R=stefan@webrtc.org
Review URL: https://codereview.webrtc.org/1227653002
Cr-Commit-Position: refs/heads/master@{#9547}
diff --git a/webrtc/modules/remote_bitrate_estimator/overuse_detector_unittest.cc b/webrtc/modules/remote_bitrate_estimator/overuse_detector_unittest.cc
index 320cb43..1bb28c8 100644
--- a/webrtc/modules/remote_bitrate_estimator/overuse_detector_unittest.cc
+++ b/webrtc/modules/remote_bitrate_estimator/overuse_detector_unittest.cc
@@ -603,14 +603,17 @@
}
class OveruseDetectorExperimentTest : public OveruseDetectorTest {
+ public:
+ OveruseDetectorExperimentTest()
+ : override_field_trials_(
+ "WebRTC-AdaptiveBweThreshold/Enabled-0.01,0.00018/") {}
+
protected:
void SetUp() override {
- test::InitFieldTrialsFromString(
- "WebRTC-AdaptiveBweThreshold/Enabled-0.01,0.00018/");
overuse_detector_.reset(new OveruseDetector(options_));
}
- void TearDown() override { test::InitFieldTrialsFromString(""); }
+ test::ScopedFieldTrials override_field_trials_;
};
TEST_F(OveruseDetectorExperimentTest, ThresholdAdapts) {
diff --git a/webrtc/test/field_trial.cc b/webrtc/test/field_trial.cc
index 1f56ad3..92aa6b0 100644
--- a/webrtc/test/field_trial.cc
+++ b/webrtc/test/field_trial.cc
@@ -45,12 +45,12 @@
void InitFieldTrialsFromString(const std::string& trials_string) {
static const char kPersistentStringSeparator = '/';
+ // Catch an error if this is called more than once.
+ assert(field_trials_initiated_ == false);
field_trials_initiated_ = true;
- if (trials_string.empty()) {
- field_trials_.clear();
+ if (trials_string == "")
return;
- }
size_t next_item = 0;
while (next_item < trials_string.length()) {
@@ -83,5 +83,18 @@
// Using abort so it crashs both in debug and release mode.
abort();
}
+
+ScopedFieldTrials::ScopedFieldTrials(const std::string& config)
+ : previous_field_trials_(field_trials_) {
+ assert(field_trials_initiated_);
+ field_trials_initiated_ = false;
+ field_trials_ = std::map<std::string, std::string>();
+ InitFieldTrialsFromString(config);
+}
+
+ScopedFieldTrials::~ScopedFieldTrials() {
+ field_trials_ = previous_field_trials_;
+}
+
} // namespace test
} // namespace webrtc
diff --git a/webrtc/test/field_trial.h b/webrtc/test/field_trial.h
index 6503254..d448f34 100644
--- a/webrtc/test/field_trial.h
+++ b/webrtc/test/field_trial.h
@@ -12,6 +12,7 @@
#define WEBRTC_TEST_FIELD_TRIAL_H_
#include <string>
+#include <map>
namespace webrtc {
namespace test {
@@ -31,6 +32,16 @@
// passed to it. That can be used to find out if a binary is parsing the flags.
void InitFieldTrialsFromString(const std::string& config);
+// This class is used to override field-trial configs within specific tests.
+// After this class goes out of scope previous field trials will be restored.
+class ScopedFieldTrials {
+ public:
+ explicit ScopedFieldTrials(const std::string& config);
+ ~ScopedFieldTrials();
+ private:
+ const std::map<std::string, std::string> previous_field_trials_;
+};
+
} // namespace test
} // namespace webrtc
