base/observer_list_unittest.cc

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#include "base/observer_list.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace {

class ObserverListTest : public testing::Test {
};

class Foo {
 public:
  virtual void Observe(int x) = 0;
  virtual ~Foo() {}
};

class Adder : public Foo {
 public:
  Adder(int scaler) : total(0), scaler_(scaler) {}
  virtual void Observe(int x) {
    total += x * scaler_;
  }
  virtual ~Adder() { }
  int total;
 private:
  int scaler_;
};

class Disrupter : public Foo {
 public:
  Disrupter(ObserverList<Foo>& list, Foo* doomed) : list_(list), doomed_(doomed) {
  }
  virtual ~Disrupter() { }
  virtual void Observe(int x) {
    list_.RemoveObserver(doomed_);
  }
 private:
  ObserverList<Foo>& list_;
  Foo* doomed_;
};

}  // namespace

TEST(ObserverListTest, BasicTest) {
  ObserverList<Foo> observer_list;
  Adder a(1), b(-1), c(1), d(-1);
  Disrupter evil(observer_list, &c);

  observer_list.AddObserver(&a);
  observer_list.AddObserver(&b);

  FOR_EACH_OBSERVER(Foo, observer_list, Observe(10));

  observer_list.AddObserver(&evil);
  observer_list.AddObserver(&c);
  observer_list.AddObserver(&d);

  FOR_EACH_OBSERVER(Foo, observer_list, Observe(10));

  EXPECT_EQ(a.total, 20);
  EXPECT_EQ(b.total, -20);
  EXPECT_EQ(c.total, 0);
  EXPECT_EQ(d.total, -10);
}