`json_schema` fails to compile with `wjson`

[rmadlal]

Describe the bug

jsonschema::make_json_schema seemingly accepts any Json type, but fails to compile with a wjson at a random location in the code:

C:\Users\Ron\Code\jsoncons\include\jsoncons_ext\jsonschema\json_schema_factory.hpp(43): error C2665: 'jsoncons::basic_json<wchar_t,jsoncons::sorted_policy,std::allocator<char>>::find': no overloaded function could convert all the argument types

The error is at this line:

jsoncons/include/jsoncons_ext/jsonschema/json_schema_factory.hpp

Line 43 in 01218c7

auto it = root_schema->find("$schema");

Replacing "$schema" with JSONCONS_CSTRING_CONSTANT(Json::char_type, "$schema") works, but there are many other places where adjustments need to be made in order for the code to be CharT-agnostic. Fixing that line makes compilation fail elsewhere.

I would expect either full support for all Json types, or an explicit enable_if for json/ojson only.

Enumerate the steps to reproduce the bug

Try to create a json_schema<wjson> object.

Include a small, self-contained example if possible

using jsoncons::wjson;
namespace jsonschema = jsoncons::jsonschema;

wjson schema = wjson::parse(LR"(
{
    "properties": {
        "foo": {
            "type": "string"
        }
    }
}
)");

jsonschema::json_schema<wjson> compiled = jsonschema::make_json_schema(schema);

What compiler, architecture, and operating system?

• Compiler: MSVC
• Architecture (e.g. x86, x64) x64
• Operating system: Windows

What jsoncons library version?

• Latest release 1.8.1
• Other release ______
• master

[danielaparker]

Yes, there are currently some limitations with what can be passed as a basic_json argument to the jsonschema functions. Wide characters aren't supported, nor are stateful allocators that lack a default constructor. I agree that this should be better documented and incorporated into constraints.