Reland "Add Dictionary API to base::Value"
This is a reland of 37c3e0b611dd5cc14d9e6ea4d53a8d69008a1c2d
Original change's description:
> Add Dictionary API to base::Value
>
> This change introduces |FindKey|, |FindKeyOfType|, |SetKey|, |DictEnd| and
> |DictItems| to base::Value. These methods are part of the new API proposal and
> abstract away the pointer based underlying storage of Dictionary Values.
>
> Bug: 646113
> Change-Id: I09150f3b2fd47e24074caa50a30a058fc4f558a7
> Reviewed-on: https://chromium-review.googlesource.com/561682
> Commit-Queue: Jan Wilken Dörrie <[email protected]>
> Reviewed-by: Brett Wilson <[email protected]>
> Reviewed-by: Vladimir Levin <[email protected]>
> Cr-Commit-Position: refs/heads/master@{#486709}
[email protected]
Bug: 646113
Change-Id: I76ee2149f18da83474a16586ee77b8e6be185814
Reviewed-on: https://chromium-review.googlesource.com/571805
Reviewed-by: Jan Wilken Dörrie <[email protected]>
Commit-Queue: Jan Wilken Dörrie <[email protected]>
Cr-Commit-Position: refs/heads/master@{#486756}diff --git a/base/values.h b/base/values.h
index 6e75540..2dfae42 100644
--- a/base/values.h
+++ b/base/values.h
@@ -34,6 +34,7 @@
#include "base/memory/manual_constructor.h"
#include "base/strings/string16.h"
#include "base/strings/string_piece.h"
+#include "base/value_iterators.h"
namespace base {
@@ -137,6 +138,59 @@
ListStorage& GetList();
const ListStorage& GetList() const;
+ using dict_iterator = detail::dict_iterator;
+ using const_dict_iterator = detail::const_dict_iterator;
+ using dict_iterator_proxy = detail::dict_iterator_proxy;
+ using const_dict_iterator_proxy = detail::const_dict_iterator_proxy;
+
+ // TODO(crbug.com/646113): Replace the following const char* and const
+ // std::string& overloads with a single base::StringPiece overload when
+ // base::less becomes available.
+
+ // |FindKey| looks up |key| in the underlying dictionary. If found, it returns
+ // an iterator to the element. Otherwise the end iterator of the dictionary is
+ // returned. Callers are expected to compare the returned iterator against
+ // |DictEnd()| in order to determine whether |key| was present.
+ // Note: This fatally asserts if type() is not Type::DICTIONARY.
+ dict_iterator FindKey(const char* key);
+ dict_iterator FindKey(const std::string& key);
+ const_dict_iterator FindKey(const char* key) const;
+ const_dict_iterator FindKey(const std::string& key) const;
+
+ // |FindKeyOfType| is similar to |FindKey|, but it also requires the found
+ // value to have type |type|. If no type is found, or the found value is of a
+ // different type the end iterator of the dictionary is returned.
+ // Callers are expected to compare the returned iterator against |DictEnd()|
+ // in order to determine whether |key| was present and of the correct |type|.
+ // Note: This fatally asserts if type() is not Type::DICTIONARY.
+ dict_iterator FindKeyOfType(const char* key, Type type);
+ dict_iterator FindKeyOfType(const std::string& key, Type type);
+ const_dict_iterator FindKeyOfType(const char* key, Type type) const;
+ const_dict_iterator FindKeyOfType(const std::string& key, Type type) const;
+
+ // |SetKey| looks up |key| in the underlying dictionary and sets the mapped
+ // value to |value|. If |key| could not be found, a new element is inserted.
+ // An iterator to the modifed item is returned.
+ // Note: This fatally asserts if type() is not Type::DICTIONARY.
+ dict_iterator SetKey(const char* key, Value value);
+ dict_iterator SetKey(const std::string& key, Value value);
+ dict_iterator SetKey(std::string&& key, Value value);
+
+ // |DictEnd| returns the end iterator of the underlying dictionary. It is
+ // intended to be used with |FindKey| in order to determine whether a given
+ // key is present in the dictionary.
+ // Note: This fatally asserts if type() is not Type::DICTIONARY.
+ dict_iterator DictEnd();
+ const_dict_iterator DictEnd() const;
+
+ // |DictItems| returns a proxy object that exposes iterators to the underlying
+ // dictionary. These are intended for iteration over all items in the
+ // dictionary and are compatible with for-each loops and standard library
+ // algorithms.
+ // Note: This fatally asserts if type() is not Type::DICTIONARY.
+ dict_iterator_proxy DictItems();
+ const_dict_iterator_proxy DictItems() const;
+
// These methods allow the convenient retrieval of the contents of the Value.
// If the current object can be converted into the given type, the value is
// returned through the |out_value| parameter and true is returned;
