Added JsonArray::remove(iterator) and JsonObject::remove(iterator) (issue #479)

CHANGELOG.md

@@ -1,6 +1,12 @@
 ArduinoJson: change log
 =======================
 
+HEAD
+----
+
+* Added `JsonArray::remove(iterator)` (issue #479)
+* Added `JsonObject::remove(iterator)`
+
 v5.8.4
 ------
 

include/ArduinoJson/Data/List.hpp

@@ -48,6 +48,20 @@ class List {
     return nodeCount;
   }
 
+  iterator add() {
+    node_type *newNode = new (_buffer) node_type();
+
+    if (_firstNode) {
+      node_type *lastNode = _firstNode;
+      while (lastNode->next) lastNode = lastNode->next;
+      lastNode->next = newNode;
+    } else {
+      _firstNode = newNode;
+    }
+
+    return iterator(newNode);
+  }
+
   iterator begin() {
     return iterator(_firstNode);
   }
@@ -62,22 +76,8 @@ class List {
     return const_iterator(NULL);
   }
 
- protected:
+  void remove(iterator it) {
-  node_type *addNewNode() {
+    node_type *nodeToRemove = it._node;
-    node_type *newNode = new (_buffer) node_type();
-
-    if (_firstNode) {
-      node_type *lastNode = _firstNode;
-      while (lastNode->next) lastNode = lastNode->next;
-      lastNode->next = newNode;
-    } else {
-      _firstNode = newNode;
-    }
-
-    return newNode;
-  }
-
-  void removeNode(node_type *nodeToRemove) {
     if (!nodeToRemove) return;
     if (nodeToRemove == _firstNode) {
       _firstNode = nodeToRemove->next;
@@ -87,6 +87,7 @@ class List {
     }
   }
 
+ protected:
   JsonBuffer *_buffer;
   node_type *_firstNode;
 };

include/ArduinoJson/Data/ListConstIterator.hpp

@@ -38,6 +38,14 @@ class ListConstIterator {
     return *this;
   }
 
+  ListConstIterator<T> &operator+=(size_t distance) {
+    while (_node && distance) {
+      _node = _node->next;
+      --distance;
+    }
+    return *this;
+  }
+
  private:
   const ListNode<T> *_node;
 };

include/ArduinoJson/Data/ListIterator.hpp

@@ -13,9 +13,14 @@
 namespace ArduinoJson {
 namespace Internals {
 
+template <typename T>
+class List;
+
 // A read-write forward iterator for List<T>
 template <typename T>
 class ListIterator {
+  friend class List<T>;
+
  public:
   explicit ListIterator(ListNode<T> *node = NULL) : _node(node) {}
 
@@ -39,6 +44,14 @@ class ListIterator {
     return *this;
   }
 
+  ListIterator<T> &operator+=(size_t distance) {
+    while (_node && distance) {
+      _node = _node->next;
+      --distance;
+    }
+    return *this;
+  }
+
   operator ListConstIterator<T>() const {
     return ListConstIterator<T>(_node);
   }

include/ArduinoJson/JsonArray.hpp

@@ -111,16 +111,15 @@ class JsonArray : public Internals::JsonPrintable<JsonArray>,
   // Gets the value at the specified index.
   template <typename T>
   typename Internals::JsonVariantAs<T>::type get(size_t index) const {
-    node_type *node = findNode(index);
+    const_iterator it = begin() += index;
-    return node ? node->content.as<T>()
+    return it != end() ? it->as<T>() : Internals::JsonVariantDefault<T>::get();
-                : Internals::JsonVariantDefault<T>::get();
   }
 
   // Check the type of the value at specified index.
   template <typename T>
   bool is(size_t index) const {
-    node_type *node = findNode(index);
+    const_iterator it = begin() += index;
-    return node ? node->content.is<T>() : false;
+    return it != end() ? it->is<T>() : false;
   }
 
   // Creates a JsonArray and adds a reference at the end of the array.
@@ -133,8 +132,9 @@ class JsonArray : public Internals::JsonPrintable<JsonArray>,
 
   // Removes element at specified index.
   void removeAt(size_t index) {
-    removeNode(findNode(index));
+    remove(begin() += index);
   }
+  using Internals::List<JsonVariant>::remove;
 
   // Returns a reference an invalid JsonArray.
   // This object is meant to replace a NULL pointer.
@@ -198,28 +198,18 @@ class JsonArray : public Internals::JsonPrintable<JsonArray>,
   }
 
  private:
-  node_type *findNode(size_t index) const {
-    node_type *node = _firstNode;
-    while (node && index--) node = node->next;
-    return node;
-  }
-
   template <typename TValueRef>
   bool set_impl(size_t index, TValueRef value) {
-    node_type *node = findNode(index);
+    iterator it = begin() += index;
-    if (!node) return false;
+    if (it == end()) return false;
-
+    return Internals::ValueSetter<TValueRef>::set(_buffer, *it, value);
-    return Internals::ValueSetter<TValueRef>::set(_buffer, node->content,
-                                                  value);
   }
 
   template <typename TValueRef>
   bool add_impl(TValueRef value) {
-    node_type *node = addNewNode();
+    iterator it = Internals::List<JsonVariant>::add();
-    if (!node) return false;
+    if (it == end()) return false;
-
+    return Internals::ValueSetter<TValueRef>::set(_buffer, *it, value);
-    return Internals::ValueSetter<TValueRef>::set(_buffer, node->content,
-                                                  value);
   }
 };
 

include/ArduinoJson/JsonObject.hpp

@@ -247,14 +247,14 @@ class JsonObject : public Internals::JsonPrintable<JsonObject>,
   typename TypeTraits::EnableIf<!TypeTraits::IsArray<TString>::value,
                                 bool>::type
   containsKey(const TString& key) const {
-    return findNode<const TString&>(key) != NULL;
+    return findKey<const TString&>(key) != end();
   }
   //
   // bool containsKey(TKey);
   // TKey = const char*, const char[N], const FlashStringHelper*
   template <typename TString>
   bool containsKey(const TString* key) const {
-    return findNode<const TString*>(key) != NULL;
+    return findKey<const TString*>(key) != end();
   }
 
   // Removes the specified key and the associated value.
@@ -265,15 +265,18 @@ class JsonObject : public Internals::JsonPrintable<JsonObject>,
   typename TypeTraits::EnableIf<!TypeTraits::IsArray<TString>::value,
                                 void>::type
   remove(const TString& key) {
-    removeNode(findNode<const TString&>(key));
+    remove(findKey<const TString&>(key));
   }
   //
   // void remove(TKey);
   // TKey = const char*, const char[N], const FlashStringHelper*
   template <typename TString>
   void remove(const TString* key) {
-    removeNode(findNode<const TString*>(key));
+    remove(findKey<const TString*>(key));
   }
+  //
+  // void remove(iterator)
+  using Internals::List<JsonPair>::remove;
 
   // Returns a reference an invalid JsonObject.
   // This object is meant to replace a NULL pointer.
@@ -286,41 +289,44 @@ class JsonObject : public Internals::JsonPrintable<JsonObject>,
  private:
   // Returns the list node that matches the specified key.
   template <typename TStringRef>
-  node_type* findNode(TStringRef key) const {
+  iterator findKey(TStringRef key) {
-    for (node_type* node = _firstNode; node; node = node->next) {
+    iterator it;
-      if (Internals::StringTraits<TStringRef>::equals(key, node->content.key))
+    for (it = begin(); it != end(); ++it) {
-        return node;
+      if (Internals::StringTraits<TStringRef>::equals(key, it->key)) break;
     }
-    return NULL;
+    return it;
+  }
+  template <typename TStringRef>
+  const_iterator findKey(TStringRef key) const {
+    return const_cast<JsonObject*>(this)->findKey<TStringRef>(key);
   }
 
   template <typename TStringRef, typename TValue>
   typename Internals::JsonVariantAs<TValue>::type get_impl(
       TStringRef key) const {
-    node_type* node = findNode<TStringRef>(key);
+    const_iterator it = findKey<TStringRef>(key);
-    return node ? node->content.value.as<TValue>()
+    return it != end() ? it->value.as<TValue>()
-                : Internals::JsonVariantDefault<TValue>::get();
+                       : Internals::JsonVariantDefault<TValue>::get();
   }
 
   template <typename TStringRef, typename TValueRef>
   bool set_impl(TStringRef key, TValueRef value) {
-    node_type* node = findNode<TStringRef>(key);
+    iterator it = findKey<TStringRef>(key);
-    if (!node) {
+    if (it == end()) {
-      node = addNewNode();
+      it = Internals::List<JsonPair>::add();
-      if (!node) return false;
+      if (it == end()) return false;
 
-      bool key_ok = Internals::ValueSetter<TStringRef>::set(
+      bool key_ok =
-          _buffer, node->content.key, key);
+          Internals::ValueSetter<TStringRef>::set(_buffer, it->key, key);
       if (!key_ok) return false;
     }
-    return Internals::ValueSetter<TValueRef>::set(_buffer, node->content.value,
+    return Internals::ValueSetter<TValueRef>::set(_buffer, it->value, value);
-                                                  value);
   }
 
   template <typename TStringRef, typename TValue>
   bool is_impl(TStringRef key) const {
-    node_type* node = findNode<TStringRef>(key);
+    const_iterator it = findKey<TStringRef>(key);
-    return node ? node->content.value.is<TValue>() : false;
+    return it != end() ? it->value.is<TValue>() : false;
   }
 
   template <typename TStringRef>

test/JsonArray/removeAt.cpp

@@ -22,7 +22,7 @@ class JsonArray_Remove_Tests : public ::testing::Test {
 
 #define TEST_(name) TEST_F(JsonArray_Remove_Tests, name)
 
-TEST_(RemoveFirstElement) {
+TEST_(RemoveFirstByIndex) {
   _array.removeAt(0);
 
   EXPECT_EQ(2, _array.size());
@@ -30,7 +30,7 @@ TEST_(RemoveFirstElement) {
   EXPECT_STREQ("three", _array[1]);
 }
 
-TEST_(RemoveMiddleElement) {
+TEST_(RemoveMiddleByIndex) {
   _array.removeAt(1);
 
   EXPECT_EQ(2, _array.size());
@@ -38,10 +38,40 @@ TEST_(RemoveMiddleElement) {
   EXPECT_STREQ("three", _array[1]);
 }
 
-TEST_(RemoveLastElement) {
+TEST_(RemoveLastByIndex) {
   _array.removeAt(2);
 
   EXPECT_EQ(2, _array.size());
   EXPECT_STREQ("one", _array[0]);
   EXPECT_STREQ("two", _array[1]);
 }
+
+TEST_(RemoveFirstByIterator) {
+  JsonArray::iterator it = _array.begin();
+  _array.remove(it);
+
+  EXPECT_EQ(2, _array.size());
+  EXPECT_STREQ("two", _array[0]);
+  EXPECT_STREQ("three", _array[1]);
+}
+
+TEST_(RemoveMiddleByIterator) {
+  JsonArray::iterator it = _array.begin();
+  ++it;
+  _array.remove(it);
+
+  EXPECT_EQ(2, _array.size());
+  EXPECT_STREQ("one", _array[0]);
+  EXPECT_STREQ("three", _array[1]);
+}
+
+TEST_(RemoveLastByIterator) {
+  JsonArray::iterator it = _array.begin();
+  ++it;
+  ++it;
+  _array.remove(it);
+
+  EXPECT_EQ(2, _array.size());
+  EXPECT_STREQ("one", _array[0]);
+  EXPECT_STREQ("two", _array[1]);
+}

test/JsonObject/remove.cpp

@@ -29,3 +29,16 @@ TEST_(SizeUntouched_WhenRemoveIsCalledWithAWrongKey) {
 
   EXPECT_EQ(1, _object.size());
 }
+
+TEST_(RemoveByIterator) {
+  DynamicJsonBuffer _jsonBuffer;
+  JsonObject& _object = _jsonBuffer.parseObject("{\"a\":0,\"b\":1,\"c\":2}");
+
+  for (JsonObject::iterator it = _object.begin(); it != _object.end(); ++it) {
+    if (it->value == 1) _object.remove(it);
+  }
+
+  char result[64];
+  _object.printTo(result);
+  EXPECT_STREQ("{\"a\":0,\"c\":2}", result);
+}