ChromeOs Power Emulation Impl

chromeos/dbus/fake_power_manager_client.cc

Index: chromeos/dbus/fake_power_manager_client.cc
diff --git a/chromeos/dbus/fake_power_manager_client.cc b/chromeos/dbus/fake_power_manager_client.cc
index 6c9a3872726a62a4ba5f0f2f353219f2e885b950..eb260005410ea877a0528b53d6f123cdad8ac1a9 100644
--- a/chromeos/dbus/fake_power_manager_client.cc
+++ b/chromeos/dbus/fake_power_manager_client.cc
@@ -6,9 +6,15 @@
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
+#include "base/logging.h"
 #include "base/time/time.h"
 
 namespace chromeos {
+namespace {
+
+const int kDefaultBatteryLifeSpanSec = 6 * 3600;  // 6 hours
+
+}  // namespace
 
 FakePowerManagerClient::FakePowerManagerClient()
     : num_request_restart_calls_(0),
@@ -23,6 +29,9 @@ FakePowerManagerClient::~FakePowerManagerClient() {
 }
 
 void FakePowerManagerClient::Init(dbus::Bus* bus) {
+  UpdatePowerProperties(
+      50, false, power_manager::PowerSupplyProperties_BatteryState_DISCHARGING,
+      power_manager::PowerSupplyProperties_ExternalPower_DISCONNECTED);
 }
 
 void FakePowerManagerClient::AddObserver(Observer* observer) {
@@ -34,7 +43,7 @@ void FakePowerManagerClient::RemoveObserver(Observer* observer) {
 }
 
 bool FakePowerManagerClient::HasObserver(const Observer* observer) const {
-  return false;
+  return observers_.HasObserver(observer);
 }
 
 void FakePowerManagerClient::SetRenderProcessManagerDelegate(
@@ -63,6 +72,7 @@ void FakePowerManagerClient::IncreaseKeyboardBrightness() {
 }
 
 void FakePowerManagerClient::RequestStatusUpdate() {
+  NotifyObservers();
 }
 
 void FakePowerManagerClient::RequestSuspend() {
@@ -129,6 +139,44 @@ void FakePowerManagerClient::SendPowerButtonEvent(
                     PowerButtonEventReceived(down, timestamp));
 }
 
+void FakePowerManagerClient::UpdatePowerProperties(
+    int battery_percent,
+    bool is_calculating_battery_time,

[Daniel Erat, 2015/07/09 15:41:47]

i'm wondering if this method should also take the time to full/empty instead of
calculating it itself. if a developer wants to try to test time-based
low-battery notifications, that seems like it'd be useful to have -- otherwise,
they'd need to fiddle around with battery_percent until they get the desired
time.

[oshima, 2015/07/09 17:10:15]

If that's the case, I'd suggest to just pass proto data instead, and
define utility functions that copys & updates the proto.

That way, a developer can have full control, while obvious cases will be simple.

[Daniel Erat, 2015/07/09 22:01:38]

just passing the proto into this class seems fine to me. and i noticed that the
design doc also shows time-to-empty/full as being directly controllable.

+    power_manager::PowerSupplyProperties::BatteryState battery_state,
+    power_manager::PowerSupplyProperties::ExternalPower external_power) {
+  int remaining_battery_sec =
+      battery_percent * kDefaultBatteryLifeSpanSec / 100;
+
+  props_.set_battery_percent(battery_percent);
+  props_.set_is_calculating_battery_time(is_calculating_battery_time);
+  props_.set_battery_state(battery_state);
+  props_.set_external_power(external_power);
+
+  // Sets |time_to_full| and |time_to_empty| based on the set properties
+  if (battery_percent == 100 &&

[Daniel Erat, 2015/07/09 15:41:47]

to match powerd, this code should just be:

  switch (battery_state) {
    case _FULL:
      // set both to 0
      break;
    case _CHARGING:
      // update _to_full and set _to_empty to 0
      break;
    case _DISCHARGING:
      // update _to_empty and set _to_full to 0
      break;
  }

using a switch statement will catch the case where a new enum value is added
later without this code being updated.

[mozartalouis, 2015/07/14 20:01:27]

Done.

+      (battery_state ==
+           power_manager::PowerSupplyProperties_BatteryState_CHARGING ||
+       battery_state ==
+           power_manager::PowerSupplyProperties_BatteryState_FULL)) {
+    props_.set_battery_time_to_full_sec(0);
+    props_.set_battery_time_to_empty_sec(0);
+  } else if (battery_state ==
+             power_manager::PowerSupplyProperties_BatteryState_CHARGING) {
+    props_.set_battery_time_to_full_sec(kDefaultBatteryLifeSpanSec -
+                                        remaining_battery_sec);
+    props_.set_battery_time_to_empty_sec(0);
+  } else {
+    props_.set_battery_time_to_full_sec(0);
+    props_.set_battery_time_to_empty_sec(remaining_battery_sec);
+  }
+
+  NotifyObservers();
+}
+
+void FakePowerManagerClient::NotifyObservers() {
+  FOR_EACH_OBSERVER(Observer, observers_, PowerChanged(props_));
+}
+
 void FakePowerManagerClient::HandleSuspendReadiness() {
   CHECK(num_pending_suspend_readiness_callbacks_ > 0);