Prioritizing input and compositor tasks in the blink scheduler.

Source/platform/scheduler/SchedulerTest.cpp

Index: Source/platform/scheduler/SchedulerTest.cpp
diff --git a/Source/platform/scheduler/SchedulerTest.cpp b/Source/platform/scheduler/SchedulerTest.cpp
index 0b35485e9232fb0518f3c5ef9e964dca34c5de72..d5e24d15502bad62925ed745110441f4734421e6 100644
--- a/Source/platform/scheduler/SchedulerTest.cpp
+++ b/Source/platform/scheduler/SchedulerTest.cpp
@@ -9,8 +9,11 @@
 #include "platform/TraceLocation.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebThread.h"
+#include "wtf/text/WTFString.h"
 
+#include <gmock/gmock.h>
 #include <gtest/gtest.h>
+#include <vector>
 
 using blink::Scheduler;
 
@@ -131,9 +134,24 @@ public:
         m_platformSupport.runPendingTasks();
     }
 
+    void appendToVector(String value)

[Sami, 2014/08/07 14:24:45]

nit: looks like this could be a normal std::string?

[alexclarke, 2014/08/07 15:15:29]

Done.

+    {
+        m_order.push_back(value);
+    }
+
+    void appendToVectorReentrant(int count)
+    {
+        m_intOrder.push_back(count);
+
+        if (count < 4)
+            m_scheduler->postTask(FROM_HERE, bind(&SchedulerTest::appendToVectorReentrant, this, count + 1));
+    }
+
 protected:
     SchedulerTestingPlatformSupport m_platformSupport;
     Scheduler* m_scheduler;
+    std::vector<String> m_order;
+    std::vector<int> m_intOrder;

[Sami, 2014/08/07 14:24:45]

bikeshed: m_reentrantOrder?

[alexclarke, 2014/08/07 15:15:29]

Done.

 };
 
 void orderedTestTask(int value, int* result)
@@ -209,4 +227,27 @@ TEST_F(SchedulerTest, TestIdleTask)
     EXPECT_EQ(4, result);
 }
 
+TEST_F(SchedulerTest, TestTaskPrioritization)
+{
+    m_scheduler->postTask(FROM_HERE, bind(&SchedulerTest::appendToVector, this, String("L1")));
+    m_scheduler->postTask(FROM_HERE, bind(&SchedulerTest::appendToVector, this, String("L2")));
+    m_scheduler->postInputTask(FROM_HERE, bind(&SchedulerTest::appendToVector, this, String("I1")));
+    m_scheduler->postInputTask(FROM_HERE, bind(&SchedulerTest::appendToVector, this, String("I2")));
+    m_scheduler->postCompositorTask(FROM_HERE, bind(&SchedulerTest::appendToVector, this, String("C1")));
+    m_scheduler->postCompositorTask(FROM_HERE, bind(&SchedulerTest::appendToVector, this, String("C2")));
+
+    runPendingTasks();
+    EXPECT_THAT(m_order, testing::ElementsAre(
+        String("I1"), String("I2"), String("C1"), String("C2"), String("L1"), String("L2")));
+}
+
+TEST_F(SchedulerTest, TestRentrantTask)
+{
+    m_scheduler->postTask(FROM_HERE, bind(&SchedulerTest::appendToVectorReentrant, this, 0));
+    runPendingTasks();
+
+    EXPECT_THAT(m_intOrder, testing::ElementsAre(0, 1, 2, 3, 4));
+}
+
+

[Sami, 2014/08/07 14:24:45]

Would you mind adding a test that checks all pending tasks are executed when the
scheduler goes away?

[alexclarke, 2014/08/07 15:15:29]

Done.

 } // namespace