Add support for unite.vim about :GoDecls / :GoDeclsDir

[delphinus]

unite.vim is a powerful "listing & selecting" plugin that looks like ctrlp.vim. I want to use :GoDeclsDir feature with unite.vim and have implemented it.

It has almost like :GoDeclsDir / :GoDecls, but differs at some points below.

• :Unite decls has features for both :GoDeclsDir and :GoDecls, but the main target is :GoDeclsDir because unite.vim has already :Unite outline that is similar to :GoDecls.
• :Unite decls does not conflict with the existent :GoDecls / :GoDeclsDir, so both of them can be used if both unite.vim and ctrp.vim are installed.

The document about this on vim-go.txt is the one I am worrying about. I placed it at the next of :GoDeclsDir, but does anyone have an idea to place somewhere better?

:Unite decls

:Unite decls:appengine.go

FYI: existing function from unite.vim :Unite outline

[delphinus]

Fixed docs & pass the tests

[fatih]

Thanks @delphinus I need to install unite.vim and see how it behaves and works. One question though, while quick skimming the code, I wonder what happens if motion returns an error. For example introduce a syntax error and call Unite. What happens? I think Unite takes care of it?

[delphinus]

Ah, good point. I see many unite addon have error handling from source command output. I will add it.

[delphinus]

done. If motion returned errors, unite handles them.

[arp242]

You should shellescape() most or all the variables you're printf-ing in the command string; otherwise stuff will break if the path contains spaces or special shell characters (this is uncommon in Go, but not illegal either, and especially an issue on systems like Windows with stuff Application Data in the path).

For example, if I use :Unite decls on ~/go/src/a/space path/space name.go I get [unite.vim] [decls] command returned invalid response..

Other than this it seems to work well 👍

[delphinus]

Thx for reviewing 👍 I fixed it.