// __ _____ _____ _____ // __| | __| | | | JSON for Modern C++ (supporting code) // | | |__ | | | | | | version 3.12.0 // |_____|_____|_____|_|___| https://github.com/nlohmann/json // // SPDX-FileCopyrightText: 2013-2026 Niels Lohmann // SPDX-License-Identifier: MIT #include "doctest_compatibility.h" #include using nlohmann::json; using nlohmann::ordered_json; TEST_CASE("ordered_json") { json j; ordered_json oj; j["element3"] = 3; j["element1"] = 1; j["element2"] = 2; oj["element3"] = 3; oj["element1"] = 1; oj["element2"] = 2; CHECK(j.dump() == "{\"element1\":1,\"element2\":2,\"element3\":3}"); CHECK(oj.dump() == "{\"element3\":3,\"element1\":1,\"element2\":2}"); CHECK(j == json(oj)); CHECK(ordered_json(json(oj)) == ordered_json(j)); j.erase("element1"); oj.erase("element1"); CHECK(j.dump() == "{\"element2\":2,\"element3\":3}"); CHECK(oj.dump() == "{\"element3\":3,\"element2\":2}"); // remove again and nothing changes j.erase("element1"); oj.erase("element1"); CHECK(j.dump() == "{\"element2\":2,\"element3\":3}"); CHECK(oj.dump() == "{\"element3\":3,\"element2\":2}"); // There are no dup keys cause constructor calls emplace... json const multi {{"z", 1}, {"m", 2}, {"m", 3}, {"y", 4}, {"m", 5}}; CHECK(multi.size() == 3); CHECK(multi.dump() == "{\"m\":2,\"y\":4,\"z\":1}"); ordered_json multi_ordered {{"z", 1}, {"m", 2}, {"m", 3}, {"y", 4}, {"m", 5}}; CHECK(multi_ordered.size() == 3); CHECK(multi_ordered.dump() == "{\"z\":1,\"m\":2,\"y\":4}"); CHECK(multi_ordered.erase("m") == 1); CHECK(multi_ordered.dump() == "{\"z\":1,\"y\":4}"); // Ranged insert test. // It seems that values shouldn't be overwritten. Only new values are added json j1 {{"c", 1}, {"b", 2}, {"a", 3}}; const json j2 {{"c", 77}, {"d", 42}, {"a", 4}}; j1.insert( j2.cbegin(), j2.cend() ); CHECK(j1.size() == 4); CHECK(j1.dump() == "{\"a\":3,\"b\":2,\"c\":1,\"d\":42}"); ordered_json oj1 {{"c", 1}, {"b", 2}, {"a", 3}}; const ordered_json oj2 {{"c", 77}, {"d", 42}, {"a", 4}}; oj1.insert( oj2.cbegin(), oj2.cend() ); CHECK(oj1.size() == 4); CHECK(oj1.dump() == "{\"c\":1,\"b\":2,\"a\":3,\"d\":42}"); } TEST_CASE("regression test for issue #3732 - iteration_proxy_value>") { // Naming the proxy type in a function-parameter position forces eager // instantiation of basic_json; previously this hit an // incomplete-type error in set_parents(). auto fn = [](nlohmann::detail::iteration_proxy_value> const & val) { return val.value(); }; static_cast(fn); } TEST_CASE("regression test - diff() must account for ordered_json member order") { SECTION("pure reorder, no value changes") { ordered_json a = {{"a", 1}, {"b", 2}}; ordered_json b = {{"b", 2}, {"a", 1}}; CHECK(a != b); // order-sensitive equality CHECK(a.patch(ordered_json::diff(a, b)) == b); } SECTION("new key must land at the front") { ordered_json c = {{"b", 2}}; ordered_json e = {{"a", 1}, {"b", 2}}; CHECK(c.patch(ordered_json::diff(c, e)) == e); } SECTION("reorder plus a value change on one of the reordered keys") { ordered_json a = {{"a", 1}, {"b", 2}}; ordered_json b = {{"b", 20}, {"a", 1}}; CHECK(a != b); CHECK(a.patch(ordered_json::diff(a, b)) == b); } SECTION("reorder plus a deleted key") { ordered_json a = {{"a", 1}, {"b", 2}, {"c", 3}}; ordered_json b = {{"b", 2}, {"a", 1}}; CHECK(a != b); CHECK(a.patch(ordered_json::diff(a, b)) == b); } SECTION("reorder plus a nested value that itself needs a recursive diff") { ordered_json a = {{"a", {{"x", 1}, {"y", 2}}}, {"b", 2}}; ordered_json b = {{"b", 2}, {"a", {{"x", 1}, {"y", 99}}}}; CHECK(a != b); CHECK(a.patch(ordered_json::diff(a, b)) == b); } SECTION("three or more keys shuffled into a different order") { ordered_json a = {{"a", 1}, {"b", 2}, {"c", 3}, {"d", 4}}; ordered_json b = {{"d", 4}, {"b", 2}, {"a", 1}, {"c", 3}}; CHECK(a != b); CHECK(a.patch(ordered_json::diff(a, b)) == b); } SECTION("matching order still produces a minimal patch (fast path unaffected)") { ordered_json a = {{"a", 1}, {"b", 2}, {"c", 3}}; ordered_json b = {{"a", 1}, {"b", 20}, {"c", 3}}; auto p = ordered_json::diff(a, b); // only the changed value should be touched, not a wholesale remove+add CHECK(p.size() == 1); CHECK(p[0]["op"] == "replace"); CHECK(p[0]["path"] == "/b"); CHECK(a.patch(p) == b); } SECTION("plain json (std::map-backed) is unaffected by same-key-different-insertion-order") { json a; a["b"] = 2; a["a"] = 1; json b; b["a"] = 1; b["b"] = 2; // std::map iteration is always sorted by key, so a == b regardless of // insertion order, and diff() must still produce the same minimal // (empty) result as before this fix CHECK(a == b); auto p = json::diff(a, b); CHECK(p.empty()); CHECK(a.patch(p) == b); } }