From 85de93ba93a001a7d709c8ec9e0a9ae7fbd9598a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Th=C3=A9o=20DELRIEU?= <theo.delrieu@tanker.io>
Date: Tue, 6 Jun 2017 13:44:35 +0200
Subject: [PATCH 1/2] add std::pair<CompatibleStringType, T> support
---
src/json.hpp | 36 +++++++++++++++++++++++++++++++---
test/src/unit-constructor1.cpp | 26 ++++++++++++++++++++++++
2 files changed, 59 insertions(+), 3 deletions(-)
diff --git a/src/json.hpp b/src/json.hpp
index 4efe51f7..87e4e546 100644
--- a/src/json.hpp
+++ b/src/json.hpp
@@ -285,7 +285,7 @@ class invalid_iterator : public exception
Exceptions have ids 3xx.
-name / id | example massage | description
+name / id | example message | description
----------------------------- | --------------- | -------------------------
json.exception.type_error.301 | cannot create object from initializer list | To create an object from an initializer list, the initializer list must consist only of a list of pairs whose first element is a string. When this constraint is violated, an array is created instead.
json.exception.type_error.302 | type must be object, but is array | During implicit or explicit value conversion, the JSON type must be compatible to the target type. For instance, a JSON string can only be converted into string types, but not into numbers or boolean types.
@@ -324,7 +324,7 @@ class type_error : public exception
Exceptions have ids 4xx.
-name / id | example massage | description
+name / id | example message | description
------------------------------- | --------------- | -------------------------
json.exception.out_of_range.401 | array index 3 is out of range | The provided array index @a i is larger than @a size-1.
json.exception.out_of_range.402 | array index '-' (3) is out of range | The special array index `-` in a JSON Pointer never describes a valid element of the array, but the index past the end. That is, it can only be used to add elements at this position, but not to read it.
@@ -355,9 +355,10 @@ class out_of_range : public exception
Exceptions have ids 5xx.
-name / id | example massage | description
+name / id | example message | description
------------------------------ | --------------- | -------------------------
json.exception.other_error.501 | unsuccessful: {"op":"test","path":"/baz", "value":"bar"} | A JSON Patch operation 'test' failed. The unsuccessful operation is also printed.
+json.exception.other_error.502 | invalid object size for conversion | Some conversions to user-defined types impose constraints on the object size (e.g. std::pair)
@since version 3.0.0
*/
@@ -865,6 +866,14 @@ void to_json(BasicJsonType& j, T (&arr)[N])
external_constructor<value_t::array>::construct(j, arr);
}
+template <typename BasicJsonType, typename CompatibleString, typename T,
+ enable_if_t<std::is_constructible<typename BasicJsonType::string_t,
+ CompatibleString>::value, int> = 0>
+void to_json(BasicJsonType& j, std::pair<CompatibleString, T> const& p)
+{
+ j[p.first] = p.second;
+}
+
///////////////
// from_json //
///////////////
@@ -1086,6 +1095,27 @@ void from_json(const BasicJsonType& j, ArithmeticType& val)
}
}
+template <typename BasicJsonType, typename CompatibleString, typename T,
+ enable_if_t<std::is_constructible<typename BasicJsonType::string_t,
+ CompatibleString>::value, int> = 0>
+void from_json(const BasicJsonType& j, std::pair<CompatibleString, T>& p)
+{
+ if (not j.is_object())
+ {
+ JSON_THROW(type_error::create(302, "type must be object, but is " + j.type_name()));
+ }
+
+ auto const inner_object = j.template get_ptr<const typename BasicJsonType::object_t*>();
+ auto const size = inner_object->size();
+ if (size != 1)
+ {
+ JSON_THROW(other_error::create(502, "conversion to std::pair requires the object to have exactly one field, but it has " + std::to_string(size)));
+ }
+ auto const& obj = *inner_object->begin();
+ // cannot use *inner_object, need to convert both members
+ p = std::make_pair(obj.first, obj.second.template get<T>());
+}
+
struct to_json_fn
{
private:
diff --git a/test/src/unit-constructor1.cpp b/test/src/unit-constructor1.cpp
index 18c032e0..f16e15c1 100644
--- a/test/src/unit-constructor1.cpp
+++ b/test/src/unit-constructor1.cpp
@@ -156,6 +156,20 @@ TEST_CASE("constructors")
CHECK(j == j_reference);
}
+ SECTION("std::pair<CompatibleString, T>")
+ {
+ std::pair<std::string, std::string> p{"first", "second"};
+ json j(p);
+
+ CHECK((j.get<decltype(p)>() == p));
+
+ std::pair<std::string, int> p2{"first", 1};
+ // use char const*
+ json j2(std::make_pair("first", 1));
+
+ CHECK((j2.get<decltype(p2)>() == p2));
+ }
+
SECTION("std::map<const char*, json>")
{
std::map<const char*, json> o {{"a", json(1)}, {"b", json(1u)}, {"c", json(2.2)}, {"d", json(false)}, {"e", json("string")}, {"f", json()}};
@@ -164,6 +178,7 @@ TEST_CASE("constructors")
CHECK(j == j_reference);
}
+
SECTION("std::multimap<json::string_t, json>")
{
std::multimap<json::string_t, json> o {{"a", json(1)}, {"b", json(1u)}, {"c", json(2.2)}, {"d", json(false)}, {"e", json("string")}, {"f", json()}};
@@ -954,6 +969,17 @@ TEST_CASE("constructors")
"[json.exception.type_error.301] cannot create object from initializer list");
}
+ SECTION("std::pair<CompatibleString, T> with error")
+ {
+ json j{{"too", "much"}, {"string", "fields"}};
+ CHECK_THROWS_AS((j.get<std::pair<std::string, std::string>>()), json::other_error);
+ CHECK_THROWS_WITH((j.get<std::pair<std::string, std::string>>()),
+ "[json.exception.other_error.502] conversion "
+ "to std::pair requires the object to have "
+ "exactly one field, but it has 2");
+ }
+
+
SECTION("empty array")
{
json j = json::array();
From cea39dfaa892115adb05985221cfa2090f92bab9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Th=C3=A9o=20DELRIEU?= <theo.delrieu@tanker.io>
Date: Tue, 6 Jun 2017 14:18:32 +0200
Subject: [PATCH 2/2] fix #600
Instead of calling CompatibleObjectType iterator-range constructor,
first convert json::value_type to CompatibleObjectType::value_type
---
src/json.hpp | 28 +++++++++++++++-----
test/src/unit-constructor1.cpp | 48 +++++++++++++++++++++++++---------
2 files changed, 56 insertions(+), 20 deletions(-)
diff --git a/src/json.hpp b/src/json.hpp
index 87e4e546..d5618fb8 100644
--- a/src/json.hpp
+++ b/src/json.hpp
@@ -867,11 +867,11 @@ void to_json(BasicJsonType& j, T (&arr)[N])
}
template <typename BasicJsonType, typename CompatibleString, typename T,
- enable_if_t<std::is_constructible<typename BasicJsonType::string_t,
- CompatibleString>::value, int> = 0>
+ enable_if_t<std::is_constructible<typename BasicJsonType::string_t,
+ CompatibleString>::value, int> = 0>
void to_json(BasicJsonType& j, std::pair<CompatibleString, T> const& p)
{
- j[p.first] = p.second;
+ j[p.first] = p.second;
}
///////////////
@@ -1046,10 +1046,24 @@ void from_json(const BasicJsonType& j, CompatibleObjectType& obj)
auto inner_object = j.template get_ptr<const typename BasicJsonType::object_t*>();
using std::begin;
using std::end;
+ using value_type = typename CompatibleObjectType::value_type;
+ std::vector<value_type> v;
+ v.reserve(j.size());
+ std::transform(
+ inner_object->begin(), inner_object->end(), std::back_inserter(v),
+ [](typename BasicJsonType::object_t::value_type const & p)
+ {
+ return value_type
+ {
+ p.first,
+ p.second
+ .template get<typename CompatibleObjectType::mapped_type>()};
+ });
// we could avoid the assignment, but this might require a for loop, which
// might be less efficient than the container constructor for some
// containers (would it?)
- obj = CompatibleObjectType(begin(*inner_object), end(*inner_object));
+ obj = CompatibleObjectType(std::make_move_iterator(begin(v)),
+ std::make_move_iterator(end(v)));
}
// overload for arithmetic types, not chosen for basic_json template arguments
@@ -1096,8 +1110,8 @@ void from_json(const BasicJsonType& j, ArithmeticType& val)
}
template <typename BasicJsonType, typename CompatibleString, typename T,
- enable_if_t<std::is_constructible<typename BasicJsonType::string_t,
- CompatibleString>::value, int> = 0>
+ enable_if_t<std::is_constructible<typename BasicJsonType::string_t,
+ CompatibleString>::value, int> = 0>
void from_json(const BasicJsonType& j, std::pair<CompatibleString, T>& p)
{
if (not j.is_object())
@@ -1112,7 +1126,7 @@ void from_json(const BasicJsonType& j, std::pair<CompatibleString, T>& p)
JSON_THROW(other_error::create(502, "conversion to std::pair requires the object to have exactly one field, but it has " + std::to_string(size)));
}
auto const& obj = *inner_object->begin();
- // cannot use *inner_object, need to convert both members
+ // cannot use *inner_object, need to convert both members
p = std::make_pair(obj.first, obj.second.template get<T>());
}
diff --git a/test/src/unit-constructor1.cpp b/test/src/unit-constructor1.cpp
index f16e15c1..db100a69 100644
--- a/test/src/unit-constructor1.cpp
+++ b/test/src/unit-constructor1.cpp
@@ -158,16 +158,27 @@ TEST_CASE("constructors")
SECTION("std::pair<CompatibleString, T>")
{
- std::pair<std::string, std::string> p{"first", "second"};
- json j(p);
+ std::pair<std::string, std::string> p{"first", "second"};
+ json j(p);
- CHECK((j.get<decltype(p)>() == p));
+ CHECK((j.get<decltype(p)>() == p));
- std::pair<std::string, int> p2{"first", 1};
- // use char const*
- json j2(std::make_pair("first", 1));
+ std::pair<std::string, int> p2{"first", 1};
+ // use char const*
+ json j2(std::make_pair("first", 1));
- CHECK((j2.get<decltype(p2)>() == p2));
+ CHECK((j2.get<decltype(p2)>() == p2));
+ }
+
+ SECTION("std::map<std::string, std::string> #600")
+ {
+ std::map<std::string, std::string> m;
+ m["a"] = "b";
+ m["c"] = "d";
+ m["e"] = "f";
+
+ json j(m);
+ CHECK((j.get<decltype(m)>() == m));
}
SECTION("std::map<const char*, json>")
@@ -971,12 +982,23 @@ TEST_CASE("constructors")
SECTION("std::pair<CompatibleString, T> with error")
{
- json j{{"too", "much"}, {"string", "fields"}};
- CHECK_THROWS_AS((j.get<std::pair<std::string, std::string>>()), json::other_error);
- CHECK_THROWS_WITH((j.get<std::pair<std::string, std::string>>()),
- "[json.exception.other_error.502] conversion "
- "to std::pair requires the object to have "
- "exactly one field, but it has 2");
+ SECTION("wrong field number")
+ {
+ json j{{"too", "much"}, {"string", "fields"}};
+ CHECK_THROWS_AS((j.get<std::pair<std::string, std::string>>()), json::other_error);
+ CHECK_THROWS_WITH((j.get<std::pair<std::string, std::string>>()),
+ "[json.exception.other_error.502] conversion "
+ "to std::pair requires the object to have "
+ "exactly one field, but it has 2");
+ }
+
+ SECTION("wrong JSON type")
+ {
+ json j(42);
+ CHECK_THROWS_AS((j.get<std::pair<std::string, std::string>>()), json::type_error);
+ CHECK_THROWS_WITH((j.get<std::pair<std::string, std::string>>()),
+ "[json.exception.type_error.302] type must be object, but is number");
+ }
}