x/tools/gopls: render package documentation when hovering over imported package name identifiers

[GSmithApps]

Is your feature request related to a problem? Please describe.
Package-level description isn't rendering

Describe the solution you'd like
I'd like the package-level description to render when hovering over an imported package, as shown in the screenshots below. ChatGPT suggests that if a package is spread across multiple files, Go uses first (alphabetically) nonempty comment, but I'm not totally sure. I don't know if VSCode is just getting confused.

Describe alternatives you've considered
One option is to ignore it. Another is to use GoLand. Another is to just always have the docs up

Additional context

GoLand

I know the docs are there. They're in doc.go, and they're rendering in Godoc, and they're showing in GoLand

https://pkg.go.dev/go.temporal.io/sdk@v1.31.0/workflow#Go

VSCode

[GSmithApps]

I might be able to help out on this too

Here's the Godoc github. I figure their logic is in here somewhere. Maybe we could use that

[firelizzard18]

@GSmithApps There's already logic in gopls for rendering package documentation. If you set "gopls": { "ui.documentation.hoverKind": "FullDocumentation" } and hover over the import URL it will render the full package documentation (the image below). The hover implementation is here. I'm not sure precisely what needs to be changed, but I believe it would only require a minor modification to hover.go. But this might not be something most users want to see. CC @findleyr

[GSmithApps]

Hey @firelizzard18 thanks so much for looking at this! Yeah I'm having luck when I hover over the import statement, but not when I hover over the variable name that it imports to. In your example, it would be if you hover over testeval somewhere later in your code where you're using it. For my example, it's when I hover over the workflow variable later in my code.

And that includes if I add that note you posted to both my project and user-level settings.json

[firelizzard18]

Yeah, that matches what I saw. While I'm confident that implementing your feature would involve tweaking the Hover function, it's not clear to me what the code path is for hovering on a package identifier (e.g. testeval) vs a package import, which is why I said I'm not certain what needs to change.

[findleyr]

This is quite old logic, and it looks like https://go.dev/cl/230417 just added special handling for import specs. The case of a PkgName object in the code falls back to default behavior for object references.

We could certainly do this, if people would find it helpful. I will move this to the gopls issue tracker as a feature request.