[clang-tools-extra] [clangd] Improve Markup Rendering (PR #140498)

[Maksim Ivanov via cfe-commits]

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@@ -118,8 +138,8 @@ class Document {
   BulletList &addBulletList();
 
   /// Doesn't contain any trailing newlines.
-  /// We try to make the markdown human-readable, e.g. avoid extra escaping.
-  /// At least one client (coc.nvim) displays the markdown verbatim!
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emaxx-google wrote:

Yes I was thinking at autodetection based on comment kinds. However looking at Headerdoc and QDoc which use the same `/*!` syntax as the one recognized by Doxygen, I suppose we'd end up regressing in some cases. Distinguishing based on presence of Doxygen `\` commands also won't help rendering Markdown-only comments.

So seems like the new Doxygen/Markdown logic should be guarded by a config option - something like `CommentFormat: Doxygen/Markdown/Plaintext` where `Plaintext` is the default that enables escaping?

> Note: this patch is the first one to support parsing of doxygen style comments and showing the parsed documentation as markdown in the hover.

I understand and I agree this is a valuable contribution long awaited by the community - thanks for tackling this. Willing to help finding a reasonable path forward for this chain of PRs, without introducing problems for existing projects.

https://github.com/llvm/llvm-project/pull/140498