vim-go

Go (golang) support for Vim. It comes with pre-defined sensible settings (like auto gofmt on save), has autocomplete, snippet support, improved syntax highlighting, go toolchain commands, etc... If needed vim-go installs all necessary binaries for providing seamless Vim integration with current commands. It's highly customizable and each individual feature can be disabled/enabled easily.

Features

• Improved Syntax highlighting, such as Functions, Operators, Methods..
• Auto completion support via gocode
• Better gofmt on save, keeps cursor position and doesn't break your undo history
• Go to symbol/declaration with godef
• Look up documentation with godoc inside Vim or open it in browser.
• Automatically import packages via goimports
• Compile and go build your package, install it with go install
• go run quickly your current file/files
• Run go test and see any errors in quickfix window
• Create a coverage profile and display annotated source code in browser to see which functions are covered.
• Lint your code with golint
• Run your code through go vet to catch static errors.
• Advanced source analysis tool with oracle
• Precise type-safe renaming of identifiers with gorename
• List all source files and dependencies
• Checking with errcheck for unchecked errors.
• Integrated and improved snippets. Supports ultisnips or neosnippet
• Share your current code to play.golang.org
• On-the-fly type information about the word under the cursor
• Tagbar support to show tags of the source code in a sidebar with gotags

Install

First of all, do not use it with other Go plugins. If you use pathogen, just clone it into your bundle directory:

$ cd ~/.vim/bundle
$ git clone https://github.com/fatih/vim-go.git

For Vundle add this line to your vimrc:

Plugin 'fatih/vim-go'

and execute :PluginInstall (or :BundleInstall for older versions of Vundle)

Please be sure all necessary binaries are installed (such as gocode, godef, goimports, etc..). You can easily install them with the included :GoInstallBinaries. Those binaries will be automatically downloaded and installed to your $GOBIN environment (if not set it will use $GOPATH/bin). It requires git and hg for fetching the individual Go packages.

Optional

• Autocompletion is enabled by default via <C-x><C-o>, to get real-time completion (completion by type) install: YCM or neocomplete.
• To get displayed source code tag informations on a sidebar install tagbar.
• For snippet feature install: ultisnips or neosnippet.
• Screenshot color scheme is a slightly modified molokai: fatih/molokai.

Usage

All features are enabled by default. There are no additional settings needed. Usage and commands are listed in doc/vim-go.txt. Just open the help page to see all commands:

:help vim-go

Mappings

vim-go has several <Plug> mappings which can be used to create custom mappings. Below are some examples you might find useful:

Show a list of interfaces which is implemented by the type under your cursor with <leader>s

au FileType go nmap <Leader>s <Plug>(go-implements)

Show type info for the word under your cursor with <leader>i (useful if you have disabled auto showing type info via g:go_auto_type_info)

au FileType go nmap <Leader>i <Plug>(go-info)

Open the relevant Godoc for the word under the cursor with <leader>gd or open it vertically with <leader>gv

au FileType go nmap <Leader>gd <Plug>(go-doc)
au FileType go nmap <Leader>gv <Plug>(go-doc-vertical)

Or open the Godoc in browser

au FileType go nmap <Leader>gb <Plug>(go-doc-browser)

Run commands, such as go run with <leader>r for the current file or go build and go test for the current package with <leader>b and <leader>t. Display a beautiful annotated source code to see which functions are covered with <leader>c.

au FileType go nmap <leader>r <Plug>(go-run)
au FileType go nmap <leader>b <Plug>(go-build)
au FileType go nmap <leader>t <Plug>(go-test)
au FileType go nmap <leader>c <Plug>(go-coverage)

By default the mapping gd is enabled which opens the target identifier in current buffer. You can also open the definition/declaration in a new vertical, horizontal or tab for the word under your cursor:

au FileType go nmap <Leader>ds <Plug>(go-def-split)
au FileType go nmap <Leader>dv <Plug>(go-def-vertical)
au FileType go nmap <Leader>dt <Plug>(go-def-tab)

Rename the identifier under the cursor to a new name

au FileType go nmap <Leader>e <Plug>(go-rename)

More <Plug> mappings can be seen with :he go-mappings. Also these are just recommendations, you are free to create more advanced mappings or functions based on :he go-commands.

Settings

Below are some settings you might find useful. For the full list see :he go-settings.

Disable opening browser after posting to your snippet to play.golang.org:

let g:go_play_open_browser = 0

By default vim-go shows errors for the fmt command, to disable it:

let g:go_fmt_fail_silently = 1

Enable goimports to automatically insert import paths instead of gofmt:

let g:go_fmt_command = "goimports"

Disable auto fmt on save:

let g:go_fmt_autosave = 0

By default binaries are installed to $GOBIN or $GOPATH/bin. To change it:

let g:go_bin_path = expand("~/.gotools")
let g:go_bin_path = "/home/fatih/.mypath"      "or give absolute path

By default syntax-highlighting for Functions, Methods and Structs is disabled. To change it:

let g:go_highlight_functions = 1
let g:go_highlight_methods = 1
let g:go_highlight_structs = 1

Snippets

Snippets are useful and very powerful. By default ultisnips is used, however you can change it to neosnippet with:

let g:go_snippet_engine = "neosnippet"

Snippet feature is enabled only if the snippet plugins are installed. Below are some examples snippets and the corresponding trigger keywords, The | character defines the cursor. Ultisnips has support for multiple cursors

ff is useful for debugging:

fmt.Printf(" | %+v\n", |)

errn expands to:

if err != nil {
    return err
}

Use gof to quickly create a anonymous goroutine :

go func() {
    |
}()

To add json tags to a struct field, use json trigger:

type foo struct {
    bar string  `json:"myField"
           ^ type `json` here, hit tab and type "myField". It will expand to `json:"myField"`
}

...

And many more! For the full list have a look at the included snippets:

Troubleshooting

I'm using Fish shell but have some problems using Vim-go

First environment variables in Fish are applied differently, it should be like:

set -x GOPATH /your/own/gopath

Second, Vim needs a POSIX compatible shell (more info here: https://github.com/dag/vim-fish#teach-a-vim-to-fish). If you use Fish to open vim, it will make certain shell based commands fail (means vim-go will fail too). To overcome this problem change the default shell by adding the following into your .vimrc (on the top of the file):

if $SHELL =~ 'fish'
  set shell='/bin/bash'
endif

or

set shell='/bin/bash'

Why another plugin?

This plugin/package is born mainly from frustration. I had to re-install my Vim plugins and especially for Go I had to install a lot of separate different plugins, setup the necessary binaries to make them work together and hope not to lose them again. Lots of plugins out there lack proper settings. This plugin is improved and contains all my fixes/changes that I'm using for months under heavy go development environment.

Give it a try. I hope you like it. Feel free to contribute to the project.

Credits

• Go Authors for official vim plugins
• Gocode, Godef, Golint, Oracle, Goimports, Gotags, Errcheck projects and authors of those projects.
• Other vim-plugins, thanks for inspiration (vim-golang, go.vim, vim-gocode, vim-godef)