Added Value::find with String key (#1467)

* Added Value::find with String key

* Fix codestyle

---------

Co-authored-by: Jordan Bayles <bayles.jordan@gmail.com>
Co-authored-by: Petukhov Timofey <Timofey.Petukhov@infotecs.ru>

Author: 3 people

include/json/value.h

@@ -513,6 +513,9 @@ class JSON_API Value {
   /// and operator[]const
   /// \note As stated elsewhere, behavior is undefined if (end-begin) >= 2^30
   Value const* find(char const* begin, char const* end) const;
+  /// Most general and efficient version of isMember()const, get()const,
+  /// and operator[]const
+  Value const* find(const String& key) const;
   /// Most general and efficient version of object-mutators.
   /// \note As stated elsewhere, behavior is undefined if (end-begin) >= 2^30
   /// \return non-zero, but JSON_ASSERT if this is neither object nor nullValue.

src/lib_json/json_value.cpp

@@ -1092,6 +1092,9 @@ Value const* Value::find(char const* begin, char const* end) const {
     return nullptr;
   return &(*it).second;
 }
+Value const* Value::find(const String& key) const {
+  return find(key.data(), key.data() + key.length());
+}
 Value* Value::demand(char const* begin, char const* end) {
   JSON_ASSERT_MESSAGE(type() == nullValue || type() == objectValue,
                       "in Json::Value::demand(begin, end): requires "
@@ -1105,7 +1108,7 @@ const Value& Value::operator[](const char* key) const {
   return *found;
 }
 Value const& Value::operator[](const String& key) const {
-  Value const* found = find(key.data(), key.data() + key.length());
+  Value const* found = find(key);
   if (!found)
     return nullSingleton();
   return *found;

src/test_lib_json/main.cpp

@@ -220,11 +220,20 @@ JSONTEST_FIXTURE_LOCAL(ValueTest, objects) {
   JSONTEST_ASSERT(foundId != nullptr);
   JSONTEST_ASSERT_EQUAL(Json::Value(1234), *foundId);
 
+  const std::string stringIdKey = "id";
+  const Json::Value* stringFoundId = object1_.find(stringIdKey);
+  JSONTEST_ASSERT(stringFoundId != nullptr);
+  JSONTEST_ASSERT_EQUAL(Json::Value(1234), *stringFoundId);
+
   const char unknownIdKey[] = "unknown id";
   const Json::Value* foundUnknownId =
       object1_.find(unknownIdKey, unknownIdKey + strlen(unknownIdKey));
   JSONTEST_ASSERT_EQUAL(nullptr, foundUnknownId);
 
+  const std::string stringUnknownIdKey = "unknown id";
+  const Json::Value* stringFoundUnknownId = object1_.find(stringUnknownIdKey);
+  JSONTEST_ASSERT_EQUAL(nullptr, stringFoundUnknownId);
+
   // Access through demand()
   const char yetAnotherIdKey[] = "yet another id";
   const Json::Value* foundYetAnotherId =