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#include "json.hh"
#include "exception.hh"
#include "string_utils.hh"
#include "unit_tests.hh"
#include "utils.hh"
#include "ranges.hh"
#include <algorithm>
#include <cstdio>
namespace Kakoune
{
String to_json(int i) { return to_string(i); }
String to_json(bool b) { return b ? "true" : "false"; }
String to_json(StringView str)
{
String res;
res.reserve(str.length() + 4);
res += '"';
for (auto it = str.begin(), end = str.end(); it != end; )
{
auto next = std::find_if(it, end, [](char c) {
return c == '\\' or c == '"' or (unsigned char) c <= 0x1F;
});
res += StringView{it, next};
if (next == end)
break;
char buf[7] = {'\\', *next, 0};
if ((unsigned char) *next <= 0x1F)
format_to(buf, "\\u{:04}", hex(*next));
res += buf;
it = next+1;
}
res += '"';
return res;
}
static bool is_digit(char c) { return c >= '0' and c <= '9'; }
static constexpr size_t max_parsing_depth = 100;
JsonResult parse_json_impl(const char* pos, const char* end, size_t depth)
{
if (not skip_while(pos, end, is_blank))
return {};
if (depth >= max_parsing_depth)
throw runtime_error("maximum parsing depth reached");
if (is_digit(*pos) or *pos == '-')
{
auto digit_end = pos + 1;
skip_while(digit_end, end, is_digit);
return { Value{str_to_int({pos, digit_end})}, digit_end };
}
if (end - pos > 4 and StringView{pos, pos+4} == "true")
return { Value{true}, pos+4 };
if (end - pos > 5 and StringView{pos, pos+5} == "false")
return { Value{false}, pos+5 };
if (*pos == '"')
{
String value;
bool escaped = false;
++pos;
for (auto string_end = pos; string_end != end; ++string_end)
{
if (escaped)
{
escaped = false;
value += StringView{pos, string_end};
value.back() = *string_end;
pos = string_end+1;
continue;
}
if (*string_end == '\\')
escaped = true;
if (*string_end == '"')
{
value += StringView{pos, string_end};
return {std::move(value), string_end+1};
}
}
return {};
}
if (*pos == '[')
{
JsonArray array;
if (++pos == end)
throw runtime_error("unable to parse array");
if (*pos == ']')
return {std::move(array), pos+1};
while (true)
{
auto [element, new_pos] = parse_json_impl(pos, end, depth+1);
if (not element)
return {};
pos = new_pos;
array.push_back(std::move(element));
if (not skip_while(pos, end, is_blank))
return {};
if (*pos == ',')
++pos;
else if (*pos == ']')
return {std::move(array), pos+1};
else
throw runtime_error("unable to parse array, expected ',' or ']'");
}
}
if (*pos == '{')
{
if (++pos == end)
throw runtime_error("unable to parse object");
JsonObject object;
if (*pos == '}')
return {std::move(object), pos+1};
while (true)
{
auto [name_value, name_end] = parse_json_impl(pos, end, depth+1);
if (not name_value)
return {};
pos = name_end;
String& name = name_value.as<String>();
if (not skip_while(pos, end, is_blank))
return {};
if (*pos++ != ':')
throw runtime_error("expected :");
auto [element, element_end] = parse_json_impl(pos, end, depth+1);
if (not element)
return {};
pos = element_end;
object.insert({ std::move(name), std::move(element) });
if (not skip_while(pos, end, is_blank))
return {};
if (*pos == ',')
++pos;
else if (*pos == '}')
return {std::move(object), pos+1};
else
throw runtime_error("unable to parse object, expected ',' or '}'");
}
}
throw runtime_error("unable to parse json");
}
JsonResult parse_json(const char* pos, const char* end) { return parse_json_impl(pos, end, 0); }
JsonResult parse_json(StringView json) { return parse_json_impl(json.begin(), json.end(), 0); }
UnitTest test_json_parser{[]()
{
{
auto value = parse_json(R"({ "jsonrpc": "2.0", "method": "keys", "params": [ "b", "l", "a", "h" ] })").value;
kak_assert(value);
}
{
auto value = parse_json("[10,20]").value;
kak_assert(value and value.is_a<JsonArray>());
kak_assert(value.as<JsonArray>().at(1).as<int>() == 20);
}
{
auto value = parse_json("-1").value;
kak_assert(value.as<int>() == -1);
}
{
auto value = parse_json("{}").value;
kak_assert(value and value.is_a<JsonObject>());
kak_assert(value.as<JsonObject>().empty());
}
{
char big_nested_array[max_parsing_depth*2+2+1] = {};
for (size_t i = 0; i < max_parsing_depth+1; i++)
{
big_nested_array[i] = '[';
big_nested_array[i+max_parsing_depth+1] = ']';
}
kak_expect_throw(runtime_error, parse_json(big_nested_array));
}
}};
UnitTest test_to_json{[]()
{
kak_assert(to_json(true) == "true");
kak_assert(to_json(false) == "false");
kak_assert(to_json(HashMap<String, Vector<int>>{{"foo", {1,2,3}}, {"\033", {3, 4, 5}}}) == R"({"foo": [1, 2, 3],"\u001b": [3, 4, 5]})");
}};
}
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