textDocument/hover Markdown and double escaping of punctuation characters

[danielmartin]

My editor is getting the following Markdown as part of the textDocument/hover payload:

Result: {
  "range": {
    "start": {
      "line": 46,
      "character": 37
    },
    "end": {
      "line": 46,
      "character": 54
    }
  },
  "contents": {
    "value": "### variable `annotationBuilder`  \n\n---\nType\\: `FBS::AnnotationPropertiesBuilder`  \n\n---\n```cpp\n// In AnnotationFlatbufferTest_PrimitiveTypeDeserialization_Test::TestBody\nFBS::AnnotationPropertiesBuilder annotationBuilder(builder)\n```",
    "kind": "markdown"
  }
}

As you can see, the colon after "Type" is double escaped: Type\\: This is causing that my editor shows an additional backlash in its documentation window:

If I paste the same Markdown into a GH issue and preview it, the same additional backslash is rendered:

The double backlash seems to be added at https://github.com/llvm/llvm-project/blob/c0b27c489104f6c3c055a3ac1573d05393fe32eb/clang-tools-extra/clangd/FormattedString.cpp#L42 I'm not very familiar with Markdown syntax so my question is, is it really needed to add a double backslash here or a single one would suffice? I'm deciding If this is something that should be fixed server-side or client-side. Thanks.

[sam-mccall]

There's just a single backslash in the content, the second one is in the JSON encoding of the string only.

That said, we're indeed doing too much escaping here - it's not necessary and apparently not recognized by GFM.

Over escaping also causes problems in coc.nvim that chooses to display and highlight the markdown.