Allow using a JsonVariant as a key or index

Closes #2080

src/ArduinoJson/Array/JsonArray.hpp

@@ -114,6 +114,15 @@ class JsonArray : public detail::VariantOperators<JsonArray> {
     detail::ArrayData::removeElement(data_, index, resources_);
   }
 
+  // Removes the element at the specified index.
+  // https://arduinojson.org/v7/api/jsonarray/remove/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value>::type remove(
+      TVariant variant) const {
+    if (variant.template is<size_t>())
+      remove(variant.template as<size_t>());
+  }
+
   // Removes all the elements of the array.
   // https://arduinojson.org/v7/api/jsonarray/clear/
   void clear() const {
@@ -122,8 +131,23 @@ class JsonArray : public detail::VariantOperators<JsonArray> {
 
   // Gets or sets the element at the specified index.
   // https://arduinojson.org/v7/api/jsonarray/subscript/
-  detail::ElementProxy<JsonArray> operator[](size_t index) const {
-    return {*this, index};
+  template <typename T>
+  typename detail::enable_if<detail::is_integral<T>::value,
+                             detail::ElementProxy<JsonArray>>::type
+  operator[](T index) const {
+    return {*this, size_t(index)};
+  }
+
+  // Gets or sets the element at the specified index.
+  // https://arduinojson.org/v7/api/jsonarray/subscript/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value,
+                             detail::ElementProxy<JsonArray>>::type
+  operator[](const TVariant& variant) const {
+    if (variant.template is<size_t>())
+      return operator[](variant.template as<size_t>());
+    else
+      return {*this, size_t(-1)};
   }
 
   operator JsonVariantConst() const {

src/ArduinoJson/Array/JsonArrayConst.hpp

@@ -45,9 +45,25 @@ class JsonArrayConst : public detail::VariantOperators<JsonArrayConst> {
 
   // Returns the element at the specified index.
   // https://arduinojson.org/v7/api/jsonarrayconst/subscript/
-  JsonVariantConst operator[](size_t index) const {
+  template <typename T>
+  typename detail::enable_if<detail::is_integral<T>::value,
+                             JsonVariantConst>::type
+  operator[](T index) const {
     return JsonVariantConst(
-        detail::ArrayData::getElement(data_, index, resources_), resources_);
+        detail::ArrayData::getElement(data_, size_t(index), resources_),
+        resources_);
+  }
+
+  // Returns the element at the specified index.
+  // https://arduinojson.org/v7/api/jsonarrayconst/subscript/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value,
+                             JsonVariantConst>::type
+  operator[](const TVariant& variant) const {
+    if (variant.template is<size_t>())
+      return operator[](variant.template as<size_t>());
+    else
+      return JsonVariantConst();
   }
 
   operator JsonVariantConst() const {

src/ArduinoJson/Document/JsonDocument.hpp

@@ -163,10 +163,19 @@ class JsonDocument : public detail::VariantOperators<const JsonDocument&> {
   // Returns true if the root object contains the specified key.
   // https://arduinojson.org/v7/api/jsondocument/containskey/
   template <typename TString>
-  bool containsKey(const TString& key) const {
+  typename detail::enable_if<detail::IsString<TString>::value, bool>::type
+  containsKey(const TString& key) const {
     return data_.getMember(detail::adaptString(key), &resources_) != 0;
   }
 
+  // Returns true if the root object contains the specified key.
+  // https://arduinojson.org/v7/api/jsondocument/containskey/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value, bool>::type
+  containsKey(const TVariant& key) const {
+    return containsKey(key.template as<const char*>());
+  }
+
   // Gets or sets a root object's member.
   // https://arduinojson.org/v7/api/jsondocument/subscript/
   template <typename TString>
@@ -207,8 +216,11 @@ class JsonDocument : public detail::VariantOperators<const JsonDocument&> {
 
   // Gets or sets a root array's element.
   // https://arduinojson.org/v7/api/jsondocument/subscript/
-  detail::ElementProxy<JsonDocument&> operator[](size_t index) {
-    return {*this, index};
+  template <typename T>
+  typename detail::enable_if<detail::is_integral<T>::value,
+                             detail::ElementProxy<JsonDocument&>>::type
+  operator[](T index) {
+    return {*this, size_t(index)};
   }
 
   // Gets a root array's member.
@@ -217,6 +229,19 @@ class JsonDocument : public detail::VariantOperators<const JsonDocument&> {
     return JsonVariantConst(data_.getElement(index, &resources_), &resources_);
   }
 
+  // Gets or sets a root object's member.
+  // https://arduinojson.org/v7/api/jsondocument/subscript/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value,
+                             JsonVariantConst>::type
+  operator[](const TVariant& key) const {
+    if (key.template is<const char*>())
+      return operator[](key.template as<const char*>());
+    if (key.template is<size_t>())
+      return operator[](key.template as<size_t>());
+    return {};
+  }
+
   // Appends a new (empty) element to the root array.
   // Returns a reference to the new element.
   // https://arduinojson.org/v7/api/jsondocument/add/
@@ -251,8 +276,11 @@ class JsonDocument : public detail::VariantOperators<const JsonDocument&> {
 
   // Removes an element of the root array.
   // https://arduinojson.org/v7/api/jsondocument/remove/
-  void remove(size_t index) {
-    detail::VariantData::removeElement(getData(), index, getResourceManager());
+  template <typename T>
+  typename detail::enable_if<detail::is_integral<T>::value>::type remove(
+      T index) {
+    detail::VariantData::removeElement(getData(), size_t(index),
+                                       getResourceManager());
   }
 
   // Removes a member of the root object.
@@ -267,13 +295,23 @@ class JsonDocument : public detail::VariantOperators<const JsonDocument&> {
   // Removes a member of the root object.
   // https://arduinojson.org/v7/api/jsondocument/remove/
   template <typename TString>
-
   typename detail::enable_if<detail::IsString<TString>::value>::type remove(
       const TString& key) {
     detail::VariantData::removeMember(getData(), detail::adaptString(key),
                                       getResourceManager());
   }
 
+  // Removes a member of the root object or an element of the root array.
+  // https://arduinojson.org/v7/api/jsondocument/remove/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value>::type remove(
+      const TVariant& key) {
+    if (key.template is<const char*>())
+      remove(key.template as<const char*>());
+    if (key.template is<size_t>())
+      remove(key.template as<size_t>());
+  }
+
   operator JsonVariant() {
     return getVariant();
   }

src/ArduinoJson/Object/JsonObject.hpp

@@ -102,7 +102,6 @@ class JsonObject : public detail::VariantOperators<JsonObject> {
   // Gets or sets the member with specified key.
   // https://arduinojson.org/v7/api/jsonobject/subscript/
   template <typename TString>
-
   typename detail::enable_if<detail::IsString<TString>::value,
                              detail::MemberProxy<JsonObject, TString>>::type
   operator[](const TString& key) const {
@@ -112,13 +111,24 @@ class JsonObject : public detail::VariantOperators<JsonObject> {
   // Gets or sets the member with specified key.
   // https://arduinojson.org/v7/api/jsonobject/subscript/
   template <typename TChar>
-
   typename detail::enable_if<detail::IsString<TChar*>::value,
                              detail::MemberProxy<JsonObject, TChar*>>::type
   operator[](TChar* key) const {
     return {*this, key};
   }
 
+  // Gets or sets the member with specified key.
+  // https://arduinojson.org/v7/api/jsonobject/subscript/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value,
+                             detail::MemberProxy<JsonObject, const char*>>::type
+  operator[](const TVariant& key) const {
+    if (key.template is<const char*>())
+      return {*this, key.template as<const char*>()};
+    else
+      return {*this, nullptr};
+  }
+
   // Removes the member at the specified iterator.
   // https://arduinojson.org/v7/api/jsonobject/remove/
   FORCE_INLINE void remove(iterator it) const {
@@ -128,11 +138,21 @@ class JsonObject : public detail::VariantOperators<JsonObject> {
   // Removes the member with the specified key.
   // https://arduinojson.org/v7/api/jsonobject/remove/
   template <typename TString>
-  FORCE_INLINE void remove(const TString& key) const {
+  typename detail::enable_if<detail::IsString<TString>::value>::type remove(
+      const TString& key) const {
     detail::ObjectData::removeMember(data_, detail::adaptString(key),
                                      resources_);
   }
 
+  // Removes the member with the specified key.
+  // https://arduinojson.org/v7/api/jsonobject/remove/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value>::type remove(
+      const TVariant& key) const {
+    if (key.template is<const char*>())
+      remove(key.template as<const char*>());
+  }
+
   // Removes the member with the specified key.
   // https://arduinojson.org/v7/api/jsonobject/remove/
   template <typename TChar>
@@ -144,7 +164,6 @@ class JsonObject : public detail::VariantOperators<JsonObject> {
   // Returns true if the object contains the specified key.
   // https://arduinojson.org/v7/api/jsonobject/containskey/
   template <typename TString>
-
   typename detail::enable_if<detail::IsString<TString>::value, bool>::type
   containsKey(const TString& key) const {
     return detail::ObjectData::getMember(data_, detail::adaptString(key),
@@ -154,13 +173,20 @@ class JsonObject : public detail::VariantOperators<JsonObject> {
   // Returns true if the object contains the specified key.
   // https://arduinojson.org/v7/api/jsonobject/containskey/
   template <typename TChar>
-
   typename detail::enable_if<detail::IsString<TChar*>::value, bool>::type
   containsKey(TChar* key) const {
     return detail::ObjectData::getMember(data_, detail::adaptString(key),
                                          resources_) != 0;
   }
 
+  // Returns true if the object contains the specified key.
+  // https://arduinojson.org/v7/api/jsonobject/containskey/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value, bool>::type
+  containsKey(const TVariant& key) const {
+    return containsKey(key.template as<const char*>());
+  }
+
   // DEPRECATED: use obj[key].to<JsonArray>() instead
   template <typename TChar>
   ARDUINOJSON_DEPRECATED("use obj[key].to<JsonArray>() instead")

src/ArduinoJson/Object/JsonObjectConst.hpp

@@ -71,7 +71,8 @@ class JsonObjectConst : public detail::VariantOperators<JsonObjectConst> {
   // Returns true if the object contains the specified key.
   // https://arduinojson.org/v7/api/jsonobjectconst/containskey/
   template <typename TString>
-  bool containsKey(const TString& key) const {
+  typename detail::enable_if<detail::IsString<TString>::value, bool>::type
+  containsKey(const TString& key) const {
     return detail::ObjectData::getMember(data_, detail::adaptString(key),
                                          resources_) != 0;
   }
@@ -84,6 +85,14 @@ class JsonObjectConst : public detail::VariantOperators<JsonObjectConst> {
                                          resources_) != 0;
   }
 
+  // Returns true if the object contains the specified key.
+  // https://arduinojson.org/v7/api/jsonobjectconst/containskey/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value, bool>::type
+  containsKey(const TVariant& key) const {
+    return containsKey(key.template as<const char*>());
+  }
+
   // Gets the member with specified key.
   // https://arduinojson.org/v7/api/jsonobjectconst/subscript/
   template <typename TString>
@@ -106,6 +115,18 @@ class JsonObjectConst : public detail::VariantOperators<JsonObjectConst> {
                             resources_);
   }
 
+  // Gets the member with specified key.
+  // https://arduinojson.org/v7/api/jsonobjectconst/subscript/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value,
+                             JsonVariantConst>::type
+  operator[](const TVariant& key) const {
+    if (key.template is<const char*>())
+      return operator[](key.template as<const char*>());
+    else
+      return JsonVariantConst();
+  }
+
   // DEPRECATED: always returns zero
   ARDUINOJSON_DEPRECATED("always returns zero")
   size_t memoryUsage() const {

src/ArduinoJson/Polyfills/type_traits/is_enum.hpp

@@ -14,7 +14,7 @@ ARDUINOJSON_BEGIN_PRIVATE_NAMESPACE
 
 template <typename T>
 struct is_enum {
-  static const bool value = is_convertible<T, int>::value &&
+  static const bool value = is_convertible<T, long long>::value &&
                             !is_class<T>::value && !is_integral<T>::value &&
                             !is_floating_point<T>::value;
 };

src/ArduinoJson/Variant/JsonVariantConst.hpp

@@ -86,9 +86,13 @@ class JsonVariantConst : public detail::VariantTag,
 
   // Gets array's element at specified index.
   // https://arduinojson.org/v7/api/jsonvariantconst/subscript/
-  JsonVariantConst operator[](size_t index) const {
+  template <typename T>
+  typename detail::enable_if<detail::is_integral<T>::value,
+                             JsonVariantConst>::type
+  operator[](T index) const {
     return JsonVariantConst(
-        detail::VariantData::getElement(data_, index, resources_), resources_);
+        detail::VariantData::getElement(data_, size_t(index), resources_),
+        resources_);
   }
 
   // Gets object's member with specified key.
@@ -113,10 +117,22 @@ class JsonVariantConst : public detail::VariantTag,
                             resources_);
   }
 
+  // Gets object's member with specified key or the array's element at the
+  // specified index.
+  // https://arduinojson.org/v7/api/jsonvariantconst/subscript/
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value,
+                             JsonVariantConst>::type
+  operator[](const TVariant& key) const {
+    if (key.template is<size_t>())
+      return operator[](key.template as<size_t>());
+    else
+      return operator[](key.template as<const char*>());
+  }
+
   // Returns true if tge object contains the specified key.
   // https://arduinojson.org/v7/api/jsonvariantconst/containskey/
   template <typename TString>
-
   typename detail::enable_if<detail::IsString<TString>::value, bool>::type
   containsKey(const TString& key) const {
     return detail::VariantData::getMember(getData(), detail::adaptString(key),
@@ -126,13 +142,18 @@ class JsonVariantConst : public detail::VariantTag,
   // Returns true if tge object contains the specified key.
   // https://arduinojson.org/v7/api/jsonvariantconst/containskey/
   template <typename TChar>
-
   typename detail::enable_if<detail::IsString<TChar*>::value, bool>::type
   containsKey(TChar* key) const {
     return detail::VariantData::getMember(getData(), detail::adaptString(key),
                                           resources_) != 0;
   }
 
+  template <typename TVariant>
+  typename detail::enable_if<detail::IsVariant<TVariant>::value, bool>::type
+  containsKey(const TVariant& key) const {
+    return containsKey(key.template as<const char*>());
+  }
+
   // DEPRECATED: always returns zero
   ARDUINOJSON_DEPRECATED("always returns zero")
   size_t memoryUsage() const {

src/ArduinoJson/Variant/VariantRefBase.hpp

@@ -169,6 +169,17 @@ class VariantRefBase : public VariantTag {
                               getResourceManager());
   }
 
+  // Removes a member of the object or an element of the array.
+  // https://arduinojson.org/v7/api/jsonvariant/remove/
+  template <typename TVariant>
+  typename enable_if<IsVariant<TVariant>::value>::type remove(
+      const TVariant& key) const {
+    if (key.template is<size_t>())
+      remove(key.template as<size_t>());
+    else
+      remove(key.template as<const char*>());
+  }
+
   // Gets or sets an array element.
   // https://arduinojson.org/v7/api/jsonvariant/subscript/
   ElementProxy<TDerived> operator[](size_t index) const;
@@ -185,6 +196,12 @@ class VariantRefBase : public VariantTag {
   typename enable_if<IsString<TChar*>::value, bool>::type containsKey(
       TChar* key) const;
 
+  // Returns true if the object contains the specified key.
+  // https://arduinojson.org/v7/api/jsonvariant/containskey/
+  template <typename TVariant>
+  typename enable_if<IsVariant<TVariant>::value, bool>::type containsKey(
+      const TVariant& key) const;
+
   // Gets or sets an object member.
   // https://arduinojson.org/v7/api/jsonvariant/subscript/
   template <typename TString>
@@ -199,6 +216,17 @@ class VariantRefBase : public VariantTag {
                                   MemberProxy<TDerived, TChar*>>::type
   operator[](TChar* key) const;
 
+  // Gets an object member or an array element.
+  // https://arduinojson.org/v7/api/jsonvariant/subscript/
+  template <typename TVariant>
+  typename enable_if<IsVariant<TVariant>::value, JsonVariantConst>::type
+  operator[](const TVariant& key) const {
+    if (key.template is<size_t>())
+      return operator[](key.template as<size_t>());
+    else
+      return operator[](key.template as<const char*>());
+  }
+
   // DEPRECATED: use add<JsonVariant>() instead
   ARDUINOJSON_DEPRECATED("use add<JsonVariant>() instead")
   JsonVariant add() const;

src/ArduinoJson/Variant/VariantRefBaseImpl.hpp

@@ -90,6 +90,13 @@ VariantRefBase<TDerived>::containsKey(TChar* key) const {
                                 getResourceManager()) != 0;
 }
 
+template <typename TDerived>
+template <typename TVariant>
+inline typename enable_if<IsVariant<TVariant>::value, bool>::type
+VariantRefBase<TDerived>::containsKey(const TVariant& key) const {
+  return containsKey(key.template as<const char*>());
+}
+
 template <typename TDerived>
 inline JsonVariant VariantRefBase<TDerived>::getVariant() const {
   return JsonVariant(getData(), getResourceManager());