Godoc not appearing in code-completion

[luca-moser]

Hi Luke.

System:

• vscode-go 0.6.26
• Visual Studio Code 0.10.6.
• Windows 10 (64-bit)

Godoc does not appear when using code-completion.

In this animation we have some code written on the right pane which calls a function from the code on the left pane. You see that the func GetGroupIDsOfUser has a comment, however, it does not appear in the code-completion:

Godoc should appear when:

• the cursor is inside the parentheses of a function call
• the auto-completion list is open with suggestions of functions

The godocs do not show up on my own code, however, when using the fmt package as an example, it only shows itself sometimes:

[lukehoban]

Yes - ideally we'll show the GoDoc information in QuickInfo and Completion as well. Currently we only show it in SignatureHelp. Should be fairly straightforward to integrate with these other features as well.

[ramya-rao-a]

We are blocked on nsf/gocode#415 to get the docs during completion.

As of now we have docs in Signature Help and Quick Info.

[ramya-rao-a]

One way we could achieve this is

• Check if the completed item is a function
• If no, then quit
• If yes, then try to get pkg name from the . preceeding the word that is being completed
• goSuggest now has access to mapping between pkg and pkg path, get pkg path from there
• Call godoc and fetch the required docs as is done here: https://github.com/Microsoft/vscode-go/blob/0.6.60/src/goDeclaration.ts#L86 You'd need func signature which is available from gocode

Will not work for pkg with alias
Need to be smart to not call godoc for the same pkg multiple times. Example: fmt.P will give multiple functions, but godoc needs to be called just once.

[antifuchs]

Just a heads-up that there's now a PR to nsf/gocode that adds a package import path field to each autocomplete symbol. It might be possible to get all the information you need from that. Please test this out and let me know if it breaks things!

[segevfiner]

Note that there is even a VS Code API meant for this case: CompletionItemProvider.resolveCompletionItem.

[ramya-rao-a]

That is a good idea @segevfiner

Using resolveCompletionItem is better as we will then be fetching docs for just the suggestion item in focus instead of doing it for all items which would happen if we were to fetch docs in the provideCompletionItems call.

If anyone is interested in picking up this item, here are a few code pointers:

• Build and Debug Extension to get a local set up of the extension up and running
• All changes would be in the goSuggest.ts file
• Extend the CompletionItem object to include a new property called package. Store the package info @antifuchs mentioned in Godoc not appearing in code-completion #194 (comment) in this object and ensure this is returned by provideCompeltionItems function
• Implement the resolveCompletionItem function in the Completion provider. You now have both the package import path and the symbol name which you can then use to call godoc to get the documentation on the symbol.

[ramya-rao-a]

This long pending feature is now out in the latest update of this extension (0.7.0)
Thanks to @segevfiner!