bluetooth: Return int8_t and use -128 for unknown tx power.

components/proximity_auth/proximity_monitor_impl_unittest.cc

Index: components/proximity_auth/proximity_monitor_impl_unittest.cc
diff --git a/components/proximity_auth/proximity_monitor_impl_unittest.cc b/components/proximity_auth/proximity_monitor_impl_unittest.cc
index 85def4bf236968ef2ed12731b2cdbd87939f7f5d..c87837c75a280e38f8aca51bf81e732afd1cdad0 100644
--- a/components/proximity_auth/proximity_monitor_impl_unittest.cc
+++ b/components/proximity_auth/proximity_monitor_impl_unittest.cc
@@ -10,6 +10,7 @@
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
+#include "base/optional.h"
 #include "base/test/histogram_tester.h"
 #include "base/test/simple_test_tick_clock.h"
 #include "base/test/test_simple_task_runner.h"
@@ -236,7 +237,7 @@ TEST_F(ProximityAuthProximityMonitorImplTest,
   monitor_.Start();
 
   ProvideConnectionInfo({0, 0, 4});
-  ProvideConnectionInfo({BluetoothDevice::kUnknownPower, 0, 4});
+  ProvideConnectionInfo({base::nullopt, 0, 4});
 
   EXPECT_FALSE(monitor_.IsUnlockAllowed());
   EXPECT_FALSE(monitor_.IsInRssiRange());
@@ -248,7 +249,7 @@ TEST_F(ProximityAuthProximityMonitorImplTest,
   monitor_.Start();
 
   ProvideConnectionInfo({0, 0, 4});
-  ProvideConnectionInfo({0, BluetoothDevice::kUnknownPower, 4});
+  ProvideConnectionInfo({0, base::nullopt, 4});
 
   EXPECT_FALSE(monitor_.IsUnlockAllowed());
   EXPECT_FALSE(monitor_.IsInRssiRange());
@@ -260,7 +261,7 @@ TEST_F(ProximityAuthProximityMonitorImplTest,
   monitor_.Start();
 
   ProvideConnectionInfo({0, 0, 4});
-  ProvideConnectionInfo({0, 0, BluetoothDevice::kUnknownPower});
+  ProvideConnectionInfo({0, 0, base::nullopt});
 
   EXPECT_FALSE(monitor_.IsUnlockAllowed());
   EXPECT_FALSE(monitor_.IsInRssiRange());
@@ -316,7 +317,7 @@ TEST_F(ProximityAuthProximityMonitorImplTest,
   monitor_.Start();
 
   ProvideConnectionInfo({0, 0, 4});
-  ProvideConnectionInfo({BluetoothDevice::kUnknownPower, 0, 4});
+  ProvideConnectionInfo({base::nullopt, 0, 4});
 
   EXPECT_FALSE(monitor_.IsUnlockAllowed());
   EXPECT_FALSE(monitor_.IsInRssiRange());
@@ -328,7 +329,7 @@ TEST_F(ProximityAuthProximityMonitorImplTest,
   monitor_.Start();
 
   ProvideConnectionInfo({0, 0, 4});
-  ProvideConnectionInfo({0, BluetoothDevice::kUnknownPower, 4});
+  ProvideConnectionInfo({0, base::nullopt, 4});
 
   EXPECT_FALSE(monitor_.IsUnlockAllowed());
   EXPECT_FALSE(monitor_.IsInRssiRange());
@@ -340,7 +341,7 @@ TEST_F(ProximityAuthProximityMonitorImplTest,
   monitor_.Start();
 
   ProvideConnectionInfo({0, 0, 4});
-  ProvideConnectionInfo({0, 0, BluetoothDevice::kUnknownPower});
+  ProvideConnectionInfo({0, 0, base::nullopt});
 
   EXPECT_FALSE(monitor_.IsUnlockAllowed());
   EXPECT_FALSE(monitor_.IsInRssiRange());
@@ -524,15 +525,42 @@ TEST_F(ProximityAuthProximityMonitorImplTest,
 }
 
 TEST_F(ProximityAuthProximityMonitorImplTest,
-       RecordProximityMetricsOnAuthSuccess_ClampedValues) {
+       RecordProximityMetricsOnAuthSuccess_ClampedValues_LowerThreshold) {
+  // Tests that we clamp values lower than -100 before histograming.
+
+  int8_t rssi = -128;
+  int8_t tx_power = -128;
+  int8_t max_tx_power = 0;
+  // The resulting TransmitPowerDelta that we try to record is -128.
+
   monitor_.Start();
-  ProvideConnectionInfo({-99999, 99999, 12345});
+  ProvideConnectionInfo({rssi, tx_power, max_tx_power});
 
   base::HistogramTester histogram_tester;
   monitor_.RecordProximityMetricsOnAuthSuccess();
   histogram_tester.ExpectUniqueSample("EasyUnlock.AuthProximity.RollingRssi",
                                       -100, 1);
   histogram_tester.ExpectUniqueSample(
+      "EasyUnlock.AuthProximity.TransmitPowerDelta", -100, 1);
+}
+
+TEST_F(ProximityAuthProximityMonitorImplTest,
+       RecordProximityMetricsOnAuthSuccess_ClampedValues_UpperThreshold) {
+  // Tests that we clamp values larger than 50 before histograming.
+
+  int8_t rssi = 126;
+  int8_t tx_power = 126;
+  int8_t max_tx_power = 0;
+  // The resulting TransmitPowerDelta that we try to record is 126.
+
+  monitor_.Start();
+  ProvideConnectionInfo({rssi, tx_power, max_tx_power});
+
+  base::HistogramTester histogram_tester;
+  monitor_.RecordProximityMetricsOnAuthSuccess();
+  histogram_tester.ExpectUniqueSample("EasyUnlock.AuthProximity.RollingRssi",
+                                      50, 1);
+  histogram_tester.ExpectUniqueSample(
       "EasyUnlock.AuthProximity.TransmitPowerDelta", 50, 1);
 }
 
@@ -549,7 +577,7 @@ TEST_F(ProximityAuthProximityMonitorImplTest,
   ProximityMonitorImpl monitor(unnamed_remote_device, std::move(clock));
   monitor.AddObserver(&observer_);
   monitor.Start();
-  ProvideConnectionInfo({127, 127, 127});
+  ProvideConnectionInfo({base::nullopt, base::nullopt, base::nullopt});
 
   base::HistogramTester histogram_tester;
   monitor.RecordProximityMetricsOnAuthSuccess();