Character escapes in jsonpath::json_location::to_string

[gerdy-d]

Describe the bug

It seems that json_location::to_string (jsonpath) only escapes single quotes (and no other characters) within a json_location_node_kind::name.

Enumerate the steps to reproduce the bug

Please see the example below.

Include a small, self-contained example if possible

Consider the following example program (#includes omitted):

    const json j = json::parse(LR"({"\\":0})");
    const std::wstring p = LR"($['\\'])";
    jsonpath::json_query(j,
                         p,
                         [](const json::string_view_type& normalized_path, const json&) {
                             std::wcout << normalized_path;
                         },
                         jsonpath::result_options::path);

This prints: $['']

I'm not entirely sure, but I would expect the program to print $['\\']

Using jsoncons::jsonpath::escape_string(node->name().c_str(), node->name().length(), buffer); at lines 331-342 seems to result in the output $['\\'], but I'm uncertain if this modification in the code would be correct.

Thanks in advance for looking into this.

What compiler, architecture, and operating system?

• Compiler: Visual C++ 2019
• Architecture (e.g. x86, x64) x86
• Operating system: Windows 10

What jsoncons library version?

• [X] Latest release 0.169.0
• [ ] Other release __
• [ ] master

[danielaparker]

Regarding your example, I'm pretty sure we don't support that combination of narrow characters and wide characters!

But yes, you're right, we should be using jsoncons::jsonpath::escape string to escape the node names. This will be fixed in the next release.

[danielaparker]

Fix is on master. This code

std::string json_string = R"({"\\":0})";
std::cout << "json string: " << json_string << "\n\n";

const json j = json::parse(json_string);

const std::string p = R"($['\\'])";
jsonpath::json_query(j,
    p,
    [j](const json::string_view_type& normalized_path, const json&) {
        auto result = jsonpath::json_query(j, normalized_path);
        std::cout << "normalized_path: " << normalized_path << ", result: " << result << "\n";
    },
    jsonpath::result_options::path);

now produces

json string: {"\\":0}

normalized_path: $['\\'], result: [0]

[gerdy-d]

Sorry for the confusion regarding narrow and wide characters, I forgot to paste this line in my example: using json = jsoncons::wojson;

Thanks for the fix!

[danielaparker]

Fix is in 0.170.0