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Actually I think the   is a bug on the lsp-mode/emacs side. But I'm not sure why gopls is returning e.g. \\. for punctuation. I'd expect \..

^ Nevermind, I confirm gopls is indeed returning escaped &, that's why I see   in the render.

This is probably because lsp-mode is requesting its hover results to be formatted in Markdown. There is an option on the language client's end to request plaintext results, but a lot of clients choose Markdown because users may have other plugins installed that display Markdown nicely. I would recommend opening up an issue to offer a configuration in lsp-mode or seeing if you can install a plugin to format the hover.

I see this is expected based on the LSP spec. So I'll dig further on the lsp-mode side.

lsp-mode change to handle this at emacs-lsp/lsp-mode#1614.

@stamblerre do you know why gopls returns so much whitespace around indents though?

For example here is the original godoc:

// Expect wraps an actual value allowing assertions to be made on it:
//    Expect("foo").To(Equal("foo"))

And the MarkupContent inserts 2 lines between the sentence and the following indent:

  "contents": {
    "value": "```go\nfunc ..Expect(actual interface{}, extra ...interface{}) ..Assertion\n```\n\n[`gomega.Expect` on pkg.go.dev](https://pkg.go.dev/github.com/onsi/gomega@v1.5.0#Expect)\n\nExpect wraps an actual value allowing assertions to be made on it\\:\n\n\n    Expect(\"foo\").To(Equal(\"foo\"))\n\n\nIf Expect is passed more than one argument it will pass the \\*first\\* argument to the matcher\\.\nAll subsequent arguments will be required to be nil\\/zero\\.\n\nThis is convenient if you want to make an assertion on a method\\/function that returns\na value and an error \\- a common patter in Go\\.\n\nFor example, given a function with signature\\:\n\n\n    func MyAmazingThing() (int, error)\n\n\nThen\\:\n\n\n    Expect(MyAmazingThing()).Should(Equal(3))\n\n\nWill succeed only if \\`MyAmazingThing\\(\\)\\` returns \\`\\(3, nil\\)\\`\n\nExpect and Ω are identical\n",
    "kind": "markdown"
  }

I believe that this is done to make the indent render properly in the Markdown. I'm not an expert, but this is the code that does the conversion: https://github.com/golang/tools/blob/f3a5411a4c3bfd7b6429abf664039dc43b37d985/internal/lsp/source/comment.go#L40.

I would imagine that the extra whitespace will not be there in the plaintext mode.