json/test/src/unit-json_pointer.cpp
Patrick Boettcher 9225cf2f57 allow push_back() and pop_back() calls on json_pointer
Putting pop_back() to public and creating a trivial push_back()
method allows users of nlohmann::json_pointer to manipulate an
existing json-pointer by adding or removing keys at the end.

This is useful for traversing a JSON-instance and keeping track
of its "absolute path" at any moment.

In my case for a schema-validator error-handler.
2019-01-15 14:43:46 +01:00

516 lines
20 KiB
C++

/*
__ _____ _____ _____
__| | __| | | | JSON for Modern C++ (test suite)
| | |__ | | | | | | version 3.5.0
|_____|_____|_____|_|___| https://github.com/nlohmann/json
Licensed under the MIT License <http://opensource.org/licenses/MIT>.
SPDX-License-Identifier: MIT
Copyright (c) 2013-2018 Niels Lohmann <http://nlohmann.me>.
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
#include "catch.hpp"
#define private public
#include <nlohmann/json.hpp>
using nlohmann::json;
TEST_CASE("JSON pointers")
{
SECTION("errors")
{
CHECK_THROWS_AS(json::json_pointer("foo"), json::parse_error&);
CHECK_THROWS_WITH(json::json_pointer("foo"),
"[json.exception.parse_error.107] parse error at byte 1: JSON pointer must be empty or begin with '/' - was: 'foo'");
CHECK_THROWS_AS(json::json_pointer("/~~"), json::parse_error&);
CHECK_THROWS_WITH(json::json_pointer("/~~"),
"[json.exception.parse_error.108] parse error: escape character '~' must be followed with '0' or '1'");
CHECK_THROWS_AS(json::json_pointer("/~"), json::parse_error&);
CHECK_THROWS_WITH(json::json_pointer("/~"),
"[json.exception.parse_error.108] parse error: escape character '~' must be followed with '0' or '1'");
json::json_pointer p;
CHECK_THROWS_AS(p.top(), json::out_of_range&);
CHECK_THROWS_WITH(p.top(),
"[json.exception.out_of_range.405] JSON pointer has no parent");
CHECK_THROWS_AS(p.pop_back(), json::out_of_range&);
CHECK_THROWS_WITH(p.pop_back(),
"[json.exception.out_of_range.405] JSON pointer has no parent");
SECTION("array index error")
{
json v = {1, 2, 3, 4};
json::json_pointer ptr("/10e");
CHECK_THROWS_AS(v[ptr], json::out_of_range&);
CHECK_THROWS_WITH(v[ptr],
"[json.exception.out_of_range.404] unresolved reference token '10e'");
}
}
SECTION("examples from RFC 6901")
{
SECTION("nonconst access")
{
json j = R"(
{
"foo": ["bar", "baz"],
"": 0,
"a/b": 1,
"c%d": 2,
"e^f": 3,
"g|h": 4,
"i\\j": 5,
"k\"l": 6,
" ": 7,
"m~n": 8
}
)"_json;
// the whole document
CHECK(j[json::json_pointer()] == j);
CHECK(j[json::json_pointer("")] == j);
// array access
CHECK(j[json::json_pointer("/foo")] == j["foo"]);
CHECK(j[json::json_pointer("/foo/0")] == j["foo"][0]);
CHECK(j[json::json_pointer("/foo/1")] == j["foo"][1]);
CHECK(j["/foo/1"_json_pointer] == j["foo"][1]);
// checked array access
CHECK(j.at(json::json_pointer("/foo/0")) == j["foo"][0]);
CHECK(j.at(json::json_pointer("/foo/1")) == j["foo"][1]);
// empty string access
CHECK(j[json::json_pointer("/")] == j[""]);
// other cases
CHECK(j[json::json_pointer("/ ")] == j[" "]);
CHECK(j[json::json_pointer("/c%d")] == j["c%d"]);
CHECK(j[json::json_pointer("/e^f")] == j["e^f"]);
CHECK(j[json::json_pointer("/g|h")] == j["g|h"]);
CHECK(j[json::json_pointer("/i\\j")] == j["i\\j"]);
CHECK(j[json::json_pointer("/k\"l")] == j["k\"l"]);
// checked access
CHECK(j.at(json::json_pointer("/ ")) == j[" "]);
CHECK(j.at(json::json_pointer("/c%d")) == j["c%d"]);
CHECK(j.at(json::json_pointer("/e^f")) == j["e^f"]);
CHECK(j.at(json::json_pointer("/g|h")) == j["g|h"]);
CHECK(j.at(json::json_pointer("/i\\j")) == j["i\\j"]);
CHECK(j.at(json::json_pointer("/k\"l")) == j["k\"l"]);
// escaped access
CHECK(j[json::json_pointer("/a~1b")] == j["a/b"]);
CHECK(j[json::json_pointer("/m~0n")] == j["m~n"]);
// unescaped access
// access to nonexisting values yield object creation
CHECK_NOTHROW(j[json::json_pointer("/a/b")] = 42);
CHECK(j["a"]["b"] == json(42));
CHECK_NOTHROW(j[json::json_pointer("/a/c/1")] = 42);
CHECK(j["a"]["c"] == json({nullptr, 42}));
CHECK_NOTHROW(j[json::json_pointer("/a/d/-")] = 42);
CHECK(j["a"]["d"] == json::array({42}));
// "/a/b" works for JSON {"a": {"b": 42}}
CHECK(json({{"a", {{"b", 42}}}})[json::json_pointer("/a/b")] == json(42));
// unresolved access
json j_primitive = 1;
CHECK_THROWS_AS(j_primitive["/foo"_json_pointer], json::out_of_range&);
CHECK_THROWS_WITH(j_primitive["/foo"_json_pointer],
"[json.exception.out_of_range.404] unresolved reference token 'foo'");
CHECK_THROWS_AS(j_primitive.at("/foo"_json_pointer), json::out_of_range&);
CHECK_THROWS_WITH(j_primitive.at("/foo"_json_pointer),
"[json.exception.out_of_range.404] unresolved reference token 'foo'");
}
SECTION("const access")
{
const json j = R"(
{
"foo": ["bar", "baz"],
"": 0,
"a/b": 1,
"c%d": 2,
"e^f": 3,
"g|h": 4,
"i\\j": 5,
"k\"l": 6,
" ": 7,
"m~n": 8
}
)"_json;
// the whole document
CHECK(j[json::json_pointer()] == j);
CHECK(j[json::json_pointer("")] == j);
// array access
CHECK(j[json::json_pointer("/foo")] == j["foo"]);
CHECK(j[json::json_pointer("/foo/0")] == j["foo"][0]);
CHECK(j[json::json_pointer("/foo/1")] == j["foo"][1]);
CHECK(j["/foo/1"_json_pointer] == j["foo"][1]);
// checked array access
CHECK(j.at(json::json_pointer("/foo/0")) == j["foo"][0]);
CHECK(j.at(json::json_pointer("/foo/1")) == j["foo"][1]);
// empty string access
CHECK(j[json::json_pointer("/")] == j[""]);
// other cases
CHECK(j[json::json_pointer("/ ")] == j[" "]);
CHECK(j[json::json_pointer("/c%d")] == j["c%d"]);
CHECK(j[json::json_pointer("/e^f")] == j["e^f"]);
CHECK(j[json::json_pointer("/g|h")] == j["g|h"]);
CHECK(j[json::json_pointer("/i\\j")] == j["i\\j"]);
CHECK(j[json::json_pointer("/k\"l")] == j["k\"l"]);
// checked access
CHECK(j.at(json::json_pointer("/ ")) == j[" "]);
CHECK(j.at(json::json_pointer("/c%d")) == j["c%d"]);
CHECK(j.at(json::json_pointer("/e^f")) == j["e^f"]);
CHECK(j.at(json::json_pointer("/g|h")) == j["g|h"]);
CHECK(j.at(json::json_pointer("/i\\j")) == j["i\\j"]);
CHECK(j.at(json::json_pointer("/k\"l")) == j["k\"l"]);
// escaped access
CHECK(j[json::json_pointer("/a~1b")] == j["a/b"]);
CHECK(j[json::json_pointer("/m~0n")] == j["m~n"]);
// unescaped access
CHECK_THROWS_AS(j.at(json::json_pointer("/a/b")), json::out_of_range&);
CHECK_THROWS_WITH(j.at(json::json_pointer("/a/b")),
"[json.exception.out_of_range.403] key 'a' not found");
// unresolved access
const json j_primitive = 1;
CHECK_THROWS_AS(j_primitive["/foo"_json_pointer], json::out_of_range&);
CHECK_THROWS_WITH(j_primitive["/foo"_json_pointer],
"[json.exception.out_of_range.404] unresolved reference token 'foo'");
CHECK_THROWS_AS(j_primitive.at("/foo"_json_pointer), json::out_of_range&);
CHECK_THROWS_WITH(j_primitive.at("/foo"_json_pointer),
"[json.exception.out_of_range.404] unresolved reference token 'foo'");
}
SECTION("user-defined string literal")
{
json j = R"(
{
"foo": ["bar", "baz"],
"": 0,
"a/b": 1,
"c%d": 2,
"e^f": 3,
"g|h": 4,
"i\\j": 5,
"k\"l": 6,
" ": 7,
"m~n": 8
}
)"_json;
// the whole document
CHECK(j[""_json_pointer] == j);
// array access
CHECK(j["/foo"_json_pointer] == j["foo"]);
CHECK(j["/foo/0"_json_pointer] == j["foo"][0]);
CHECK(j["/foo/1"_json_pointer] == j["foo"][1]);
}
}
SECTION("array access")
{
SECTION("nonconst access")
{
json j = {1, 2, 3};
const json j_const = j;
// check reading access
CHECK(j["/0"_json_pointer] == j[0]);
CHECK(j["/1"_json_pointer] == j[1]);
CHECK(j["/2"_json_pointer] == j[2]);
// assign to existing index
j["/1"_json_pointer] = 13;
CHECK(j[1] == json(13));
// assign to nonexisting index
j["/3"_json_pointer] = 33;
CHECK(j[3] == json(33));
// assign to nonexisting index (with gap)
j["/5"_json_pointer] = 55;
CHECK(j == json({1, 13, 3, 33, nullptr, 55}));
// error with leading 0
CHECK_THROWS_AS(j["/01"_json_pointer], json::parse_error&);
CHECK_THROWS_WITH(j["/01"_json_pointer],
"[json.exception.parse_error.106] parse error: array index '01' must not begin with '0'");
CHECK_THROWS_AS(j_const["/01"_json_pointer], json::parse_error&);
CHECK_THROWS_WITH(j_const["/01"_json_pointer],
"[json.exception.parse_error.106] parse error: array index '01' must not begin with '0'");
CHECK_THROWS_AS(j.at("/01"_json_pointer), json::parse_error&);
CHECK_THROWS_WITH(j.at("/01"_json_pointer),
"[json.exception.parse_error.106] parse error: array index '01' must not begin with '0'");
CHECK_THROWS_AS(j_const.at("/01"_json_pointer), json::parse_error&);
CHECK_THROWS_WITH(j_const.at("/01"_json_pointer),
"[json.exception.parse_error.106] parse error: array index '01' must not begin with '0'");
// error with incorrect numbers
CHECK_THROWS_AS(j["/one"_json_pointer] = 1, json::parse_error&);
CHECK_THROWS_WITH(j["/one"_json_pointer] = 1,
"[json.exception.parse_error.109] parse error: array index 'one' is not a number");
CHECK_THROWS_AS(j_const["/one"_json_pointer] == 1, json::parse_error&);
CHECK_THROWS_WITH(j_const["/one"_json_pointer] == 1,
"[json.exception.parse_error.109] parse error: array index 'one' is not a number");
CHECK_THROWS_AS(j.at("/one"_json_pointer) = 1, json::parse_error&);
CHECK_THROWS_WITH(j.at("/one"_json_pointer) = 1,
"[json.exception.parse_error.109] parse error: array index 'one' is not a number");
CHECK_THROWS_AS(j_const.at("/one"_json_pointer) == 1, json::parse_error&);
CHECK_THROWS_WITH(j_const.at("/one"_json_pointer) == 1,
"[json.exception.parse_error.109] parse error: array index 'one' is not a number");
CHECK_THROWS_AS(json({{"/list/0", 1}, {"/list/1", 2}, {"/list/three", 3}}).unflatten(), json::parse_error&);
CHECK_THROWS_WITH(json({{"/list/0", 1}, {"/list/1", 2}, {"/list/three", 3}}).unflatten(),
"[json.exception.parse_error.109] parse error: array index 'three' is not a number");
// assign to "-"
j["/-"_json_pointer] = 99;
CHECK(j == json({1, 13, 3, 33, nullptr, 55, 99}));
// error when using "-" in const object
CHECK_THROWS_AS(j_const["/-"_json_pointer], json::out_of_range&);
CHECK_THROWS_WITH(j_const["/-"_json_pointer],
"[json.exception.out_of_range.402] array index '-' (3) is out of range");
// error when using "-" with at
CHECK_THROWS_AS(j.at("/-"_json_pointer), json::out_of_range&);
CHECK_THROWS_WITH(j.at("/-"_json_pointer),
"[json.exception.out_of_range.402] array index '-' (7) is out of range");
CHECK_THROWS_AS(j_const.at("/-"_json_pointer), json::out_of_range&);
CHECK_THROWS_WITH(j_const.at("/-"_json_pointer),
"[json.exception.out_of_range.402] array index '-' (3) is out of range");
}
SECTION("const access")
{
const json j = {1, 2, 3};
// check reading access
CHECK(j["/0"_json_pointer] == j[0]);
CHECK(j["/1"_json_pointer] == j[1]);
CHECK(j["/2"_json_pointer] == j[2]);
// assign to nonexisting index
CHECK_THROWS_AS(j.at("/3"_json_pointer), json::out_of_range&);
CHECK_THROWS_WITH(j.at("/3"_json_pointer),
"[json.exception.out_of_range.401] array index 3 is out of range");
// assign to nonexisting index (with gap)
CHECK_THROWS_AS(j.at("/5"_json_pointer), json::out_of_range&);
CHECK_THROWS_WITH(j.at("/5"_json_pointer),
"[json.exception.out_of_range.401] array index 5 is out of range");
// assign to "-"
CHECK_THROWS_AS(j["/-"_json_pointer], json::out_of_range&);
CHECK_THROWS_WITH(j["/-"_json_pointer],
"[json.exception.out_of_range.402] array index '-' (3) is out of range");
CHECK_THROWS_AS(j.at("/-"_json_pointer), json::out_of_range&);
CHECK_THROWS_WITH(j.at("/-"_json_pointer),
"[json.exception.out_of_range.402] array index '-' (3) is out of range");
}
}
SECTION("flatten")
{
json j =
{
{"pi", 3.141},
{"happy", true},
{"name", "Niels"},
{"nothing", nullptr},
{
"answer", {
{"everything", 42}
}
},
{"list", {1, 0, 2}},
{
"object", {
{"currency", "USD"},
{"value", 42.99},
{"", "empty string"},
{"/", "slash"},
{"~", "tilde"},
{"~1", "tilde1"}
}
}
};
json j_flatten =
{
{"/pi", 3.141},
{"/happy", true},
{"/name", "Niels"},
{"/nothing", nullptr},
{"/answer/everything", 42},
{"/list/0", 1},
{"/list/1", 0},
{"/list/2", 2},
{"/object/currency", "USD"},
{"/object/value", 42.99},
{"/object/", "empty string"},
{"/object/~1", "slash"},
{"/object/~0", "tilde"},
{"/object/~01", "tilde1"}
};
// check if flattened result is as expected
CHECK(j.flatten() == j_flatten);
// check if unflattened result is as expected
CHECK(j_flatten.unflatten() == j);
// error for nonobjects
CHECK_THROWS_AS(json(1).unflatten(), json::type_error&);
CHECK_THROWS_WITH(json(1).unflatten(),
"[json.exception.type_error.314] only objects can be unflattened");
// error for nonprimitve values
CHECK_THROWS_AS(json({{"/1", {1, 2, 3}}}).unflatten(), json::type_error&);
CHECK_THROWS_WITH(json({{"/1", {1, 2, 3}}}).unflatten(),
"[json.exception.type_error.315] values in object must be primitive");
// error for conflicting values
json j_error = {{"", 42}, {"/foo", 17}};
CHECK_THROWS_AS(j_error.unflatten(), json::type_error&);
CHECK_THROWS_WITH(j_error.unflatten(),
"[json.exception.type_error.313] invalid value to unflatten");
// explicit roundtrip check
CHECK(j.flatten().unflatten() == j);
// roundtrip for primitive values
json j_null;
CHECK(j_null.flatten().unflatten() == j_null);
json j_number = 42;
CHECK(j_number.flatten().unflatten() == j_number);
json j_boolean = false;
CHECK(j_boolean.flatten().unflatten() == j_boolean);
json j_string = "foo";
CHECK(j_string.flatten().unflatten() == j_string);
// roundtrip for empty structured values (will be unflattened to null)
json j_array(json::value_t::array);
CHECK(j_array.flatten().unflatten() == json());
json j_object(json::value_t::object);
CHECK(j_object.flatten().unflatten() == json());
}
SECTION("string representation")
{
for (auto ptr :
{"", "/foo", "/foo/0", "/", "/a~1b", "/c%d", "/e^f", "/g|h", "/i\\j", "/k\"l", "/ ", "/m~0n"
})
{
CHECK(json::json_pointer(ptr).to_string() == ptr);
}
}
SECTION("conversion")
{
SECTION("array")
{
json j;
// all numbers -> array
j["/12"_json_pointer] = 0;
CHECK(j.is_array());
}
SECTION("object")
{
json j;
// contains a number, but is not a number -> object
j["/a12"_json_pointer] = 0;
CHECK(j.is_object());
}
}
SECTION("push and pop")
{
const json j =
{
{"", "Hello"},
{"pi", 3.141},
{"happy", true},
{"name", "Niels"},
{"nothing", nullptr},
{
"answer", {
{"everything", 42}
}
},
{"list", {1, 0, 2}},
{
"object", {
{"currency", "USD"},
{"value", 42.99},
{"", "empty string"},
{"/", "slash"},
{"~", "tilde"},
{"~1", "tilde1"}
}
}
};
// empty json_pointer returns the root JSON-object
auto ptr = ""_json_pointer;
CHECK(j[ptr] == j);
// simple field access
ptr.push_back("pi");
CHECK(j[ptr] == j["pi"]);
ptr.pop_back();
CHECK(j[ptr] == j);
// object and children access
ptr.push_back("answer");
ptr.push_back("everything");
CHECK(j[ptr] == j["answer"]["everything"]);
ptr.pop_back();
ptr.pop_back();
CHECK(j[ptr] == j);
// push key which has to be encoded
ptr.push_back("object");
ptr.push_back("/");
CHECK(j[ptr] == j["object"]["/"]);
CHECK(ptr.to_string() == "/object/~1");
}
}