Deflake Mac views_unittest's MenuRunnerCocoaTest.RunMenuAndCancel

ui/events/base_event_utils.cc

Index: ui/events/base_event_utils.cc
diff --git a/ui/events/base_event_utils.cc b/ui/events/base_event_utils.cc
index d4545bc45c4560dddc39c2c217a5e0045dd39914..e5500d7f7367cb43e69940acb4fcfeebb374f2d6 100644
--- a/ui/events/base_event_utils.cc
+++ b/ui/events/base_event_utils.cc
@@ -13,6 +13,8 @@
 #include "ui/events/event_constants.h"
 #include "ui/events/event_switches.h"
 
+bool g_no_mock_time = false;
+
 namespace ui {
 
 namespace {
@@ -48,11 +50,14 @@ base::LazyInstance<std::unique_ptr<base::TickClock>>::Leaky g_tick_clock =
     LAZY_INSTANCE_INITIALIZER;
 
 base::TimeTicks EventTimeForNow() {
+  if (g_no_mock_time)
+    DCHECK(!g_tick_clock.Get());

[tapted, 2016/06/30 07:02:49]

So I got this to fail at [ RUN      ] MenuRunnerCocoaTest.RunMenuAndCancel
[9380:1287:0626/225619:5850751330859:FATAL:base_event_utils.cc(54)] Check
failed: !g_tick_clock.Get(). 
0   views_unittests                     0x000000010bf179f3
_ZN4base5debug10StackTraceC1Ev + 19
1   views_unittests                     0x000000010bf3b3d7
_ZN7logging10LogMessageD2Ev + 71
2   views_unittests                     0x000000010c64b7b6
_ZN2ui15EventTimeForNowEv + 166
3   views_unittests                     0x000000010bd70413
_ZN5views4test41MenuRunnerCocoaTest_RunMenuAndCancel_Test8TestBodyEv + 35
4   views_unittests                     0x000000010d80496a
_ZN7testing4Test3RunEv + 474
5   views_unittests                     0x000000010d80555a
_ZN7testing8TestInfo3RunEv + 410
6   views_unittests                     0x000000010d805be3
_ZN7testing8TestCase3RunEv + 451
7   views_unittests                     0x000000010d80cfa9
_ZN7testing8internal12UnitTestImpl11RunAllTestsEv + 825
8   views_unittests                     0x000000010d80cc3d
_ZN7testing8UnitTest3RunEv + 269
9   views_unittests                     0x000000010c016f1f
_ZN4base9TestSuite3RunEv + 127
10  views_unittests                     0x000000010c02dd39
_ZN4base15LaunchUnitTestsEiPPcRKNS_8CallbackIFivELNS_8internal8CopyModeE1EEE +
137
11  views_unittests                     0x000000010c692c0e
_ZN5views14ViewsTestSuite8RunTestsEv + 110
12  views_unittests                     0x000000010be4cbd9 main + 41
13  views_unittests                     0x000000010bcbf0b4 start + 52
14  ???                                 0x0000000000000007 0x0 + 7

before it passed on a retry. So that confirms the test is picking up global
state when it shouldn't. Then it also allowed me to verify whether having the
EventGenerator destructor undo the stuff it does is enough to avoid the problem
(it did! \o/)

   return g_tick_clock.Get() ? g_tick_clock.Get()->NowTicks()
                             : base::TimeTicks::Now();
 }
 
 void SetEventTickClockForTesting(std::unique_ptr<base::TickClock> tick_clock) {
+  DCHECK(!g_no_mock_time);
   g_tick_clock.Get() = std::move(tick_clock);
 }