2 files changed, 55 insertions, 0 deletions
diff --git a/base/values.h b/base/values.h
index 90cc40c..aa26b3e 100644
--- a/base/values.h
+++ b/base/values.h
@@ -342,6 +342,24 @@ class BASE_EXPORT DictionaryValue : public Value {
   key_iterator begin_keys() const { return key_iterator(dictionary_.begin()); }
   key_iterator end_keys() const { return key_iterator(dictionary_.end()); }
 
+  // This class provides an iterator over both keys and values in the
+  // dictionary.  It can't be used to modify the dictionary.
+  class Iterator {
+   public:
+    explicit Iterator(const DictionaryValue& target)
+        : target_(target), it_(target.dictionary_.begin()) {}
+
+    bool HasNext() const { return it_ != target_.dictionary_.end(); }
+    void Advance() { ++it_; }
+
+    const std::string& key() const { return it_->first; }
+    const Value& value() const { return *it_->second; }
+
+   private:
+    const DictionaryValue& target_;
+    ValueMap::const_iterator it_;
+  };
+
   // Overridden from Value:
   virtual DictionaryValue* DeepCopy() const OVERRIDE;
   virtual bool Equals(const Value* other) const OVERRIDE;
diff --git a/base/values_unittest.cc b/base/values_unittest.cc
index 458a4e1..806347c 100644
--- a/base/values_unittest.cc
+++ b/base/values_unittest.cc
@@ -702,4 +702,41 @@ TEST(ValuesTest, MergeDictionary) {
   EXPECT_EQ("sub_merge_key_value_merge", sub_merge_key_value); // Merged in.
 }
 
+TEST(ValuesTest, DictionaryIterator) {
+  DictionaryValue dict;
+  for (DictionaryValue::Iterator it(dict); it.HasNext(); it.Advance()) {
+    ADD_FAILURE();
+  }
+
+  StringValue value1("value1");
+  dict.Set("key1", value1.DeepCopy());
+  bool seen1 = false;
+  for (DictionaryValue::Iterator it(dict); it.HasNext(); it.Advance()) {
+    EXPECT_FALSE(seen1);
+    EXPECT_EQ("key1", it.key());
+    EXPECT_TRUE(value1.Equals(&it.value()));
+    seen1 = true;
+  }
+  EXPECT_TRUE(seen1);
+
+  StringValue value2("value2");
+  dict.Set("key2", value2.DeepCopy());
+  bool seen2 = seen1 = false;
+  for (DictionaryValue::Iterator it(dict); it.HasNext(); it.Advance()) {
+    if (it.key() == "key1") {
+      EXPECT_FALSE(seen1);
+      EXPECT_TRUE(value1.Equals(&it.value()));
+      seen1 = true;
+    } else if (it.key() == "key2") {
+      EXPECT_FALSE(seen2);
+      EXPECT_TRUE(value2.Equals(&it.value()));
+      seen2 = true;
+    } else {
+      ADD_FAILURE();
+    }
+  }
+  EXPECT_TRUE(seen1);
+  EXPECT_TRUE(seen2);
+}
+
 }  // namespace base