chore: import upstream snapshot with attribution

2026-07-13 13:29:29 +08:00
commit f52cf32e56
1718 changed files with 366293 additions and 0 deletions
@@ -0,0 +1,189 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "butil/observer_list.h"
+
+#include <vector>
+
+#include "butil/compiler_specific.h"
+#include "butil/memory/weak_ptr.h"
+#include "butil/threading/platform_thread.h"
+#include <gtest/gtest.h>
+
+namespace butil {
+namespace {
+
+class Foo {
+ public:
+  virtual void Observe(int x) = 0;
+  virtual ~Foo() {}
+};
+
+class Adder : public Foo {
+ public:
+  explicit Adder(int scaler) : total(0), scaler_(scaler) {}
+  virtual void Observe(int x) OVERRIDE {
+    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) OVERRIDE {
+    list_->RemoveObserver(doomed_);
+  }
+
+ private:
+  ObserverList<Foo>* list_;
+  Foo* doomed_;
+};
+
+template <typename ObserverListType>
+class AddInObserve : public Foo {
+ public:
+  explicit AddInObserve(ObserverListType* observer_list)
+      : added(false),
+        observer_list(observer_list),
+        adder(1) {
+  }
+
+  virtual void Observe(int x) OVERRIDE {
+    if (!added) {
+      added = true;
+      observer_list->AddObserver(&adder);
+    }
+  }
+
+  bool added;
+  ObserverListType* observer_list;
+  Adder adder;
+};
+
+TEST(ObserverListTest, BasicTest) {
+  ObserverList<Foo> observer_list;
+  Adder a(1), b(-1), c(1), d(-1), e(-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);
+
+  // Removing an observer not in the list should do nothing.
+  observer_list.RemoveObserver(&e);
+
+  FOR_EACH_OBSERVER(Foo, observer_list, Observe(10));
+
+  EXPECT_EQ(20, a.total);
+  EXPECT_EQ(-20, b.total);
+  EXPECT_EQ(0, c.total);
+  EXPECT_EQ(-10, d.total);
+  EXPECT_EQ(0, e.total);
+}
+
+TEST(ObserverListTest, Existing) {
+  ObserverList<Foo> observer_list(ObserverList<Foo>::NOTIFY_EXISTING_ONLY);
+  Adder a(1);
+  AddInObserve<ObserverList<Foo> > b(&observer_list);
+
+  observer_list.AddObserver(&a);
+  observer_list.AddObserver(&b);
+
+  FOR_EACH_OBSERVER(Foo, observer_list, Observe(1));
+
+  EXPECT_TRUE(b.added);
+  // B's adder should not have been notified because it was added during
+  // notification.
+  EXPECT_EQ(0, b.adder.total);
+
+  // Notify again to make sure b's adder is notified.
+  FOR_EACH_OBSERVER(Foo, observer_list, Observe(1));
+  EXPECT_EQ(1, b.adder.total);
+}
+
+class AddInClearObserve : public Foo {
+ public:
+  explicit AddInClearObserve(ObserverList<Foo>* list)
+      : list_(list), added_(false), adder_(1) {}
+
+  virtual void Observe(int /* x */) OVERRIDE {
+    list_->Clear();
+    list_->AddObserver(&adder_);
+    added_ = true;
+  }
+
+  bool added() const { return added_; }
+  const Adder& adder() const { return adder_; }
+
+ private:
+  ObserverList<Foo>* const list_;
+
+  bool added_;
+  Adder adder_;
+};
+
+TEST(ObserverListTest, ClearNotifyAll) {
+  ObserverList<Foo> observer_list;
+  AddInClearObserve a(&observer_list);
+
+  observer_list.AddObserver(&a);
+
+  FOR_EACH_OBSERVER(Foo, observer_list, Observe(1));
+  EXPECT_TRUE(a.added());
+  EXPECT_EQ(1, a.adder().total)
+      << "Adder should observe once and have sum of 1.";
+}
+
+TEST(ObserverListTest, ClearNotifyExistingOnly) {
+  ObserverList<Foo> observer_list(ObserverList<Foo>::NOTIFY_EXISTING_ONLY);
+  AddInClearObserve a(&observer_list);
+
+  observer_list.AddObserver(&a);
+
+  FOR_EACH_OBSERVER(Foo, observer_list, Observe(1));
+  EXPECT_TRUE(a.added());
+  EXPECT_EQ(0, a.adder().total)
+      << "Adder should not observe, so sum should still be 0.";
+}
+
+class ListDestructor : public Foo {
+ public:
+  explicit ListDestructor(ObserverList<Foo>* list) : list_(list) {}
+  virtual ~ListDestructor() {}
+
+  virtual void Observe(int x) OVERRIDE {
+    delete list_;
+  }
+
+ private:
+  ObserverList<Foo>* list_;
+};
+
+
+TEST(ObserverListTest, IteratorOutlivesList) {
+  ObserverList<Foo>* observer_list = new ObserverList<Foo>;
+  ListDestructor a(observer_list);
+  observer_list->AddObserver(&a);
+
+  FOR_EACH_OBSERVER(Foo, *observer_list, Observe(0));
+  // If this test fails, there'll be Valgrind errors when this function goes out
+  // of scope.
+}
+
+}  // namespace
+}  // namespace butil