# vim-go

Go (golang) support for Vim, which comes with pre-defined sensible settings (like
auto gofmt on save), with autocomplete, snippet support, improved syntax
highlighting, go toolchain commands, and more.  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.

![vim-go](https://dl.dropboxusercontent.com/u/174404/vim-go-2.png)

## Features

* Improved Syntax highlighting with items such as Functions, Operators, Methods.
* Auto completion support via `gocode`
* Better `gofmt` on save, which 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 `:GoImport` or plug it into autosave
* Compile your package with `:GoBuild`, install it with `:GoInstall` or test
  them with `:GoTest` (also supports running single tests via `:GoTestFunc`)
* Quickly execute your current file/files with `:GoRun`
* Automatic `GOPATH` detection based on the directory structure (i.e. `gb`
  projects, `godep` vendored projects)
* Change or display `GOPATH` with `:GoPath`
* Create a coverage profile and display annotated source code in browser to see
  which functions are covered with `:GoCoverage`
* Call `gometalinter` with `:GoMetaLinter`, which invokes all possible linters
  (golint, vet, errcheck, deadcode, etc..) and shows the warnings/errors
* Lint your code with `:GoLint`
* Run your code through `:GoVet` to catch static errors
* Advanced source analysis tools utilizing oracle, such as `:GoImplements`,
  `:GoCallees`, and `:GoReferrers`
* Precise type-safe renaming of identifiers with `:GoRename`
* List all source files and dependencies
* Unchecked error checking with `:GoErrCheck`
* Integrated and improved snippets, supporting `ultisnips` or `neosnippet`
* Share your current code to [play.golang.org](http://play.golang.org) with `:GoPlay`
* On-the-fly type information about the word under the cursor. Plug it into
  your custom vim function.
* Tagbar support to show tags of the source code in a sidebar with `gotags`
* Custom vim text objects such as `a function` or `inner function`
* All commands support collecting and displaying errors in Vim's location
  list.

## Install

Vim-go follows the standard runtime path structure, so I highly recommend to use
a common and well known plugin manager to install vim-go. Do not use vim-go with
other Go oriented vim plugins. For Pathogen just clone the repo. For other plugin managers
add the appropriate lines and execute the plugin's install command.

*  [Pathogen](https://github.com/tpope/vim-pathogen)
  * `git clone https://github.com/fatih/vim-go.git ~/.vim/bundle/vim-go`
*  [vim-plug](https://github.com/junegunn/vim-plug)
  * `Plug 'fatih/vim-go'`
*  [NeoBundle](https://github.com/Shougo/neobundle.vim)
  * `NeoBundle 'fatih/vim-go'`
*  [Vundle](https://github.com/gmarik/vundle)
  * `Plugin 'fatih/vim-go'`

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

### Optional

* Autocompletion is enabled by default via `<C-x><C-o>`. To get real-time
completion (completion by type) install:
[YCM](https://github.com/Valloric/YouCompleteMe) or
[neocomplete](https://github.com/Shougo/neocomplete.vim).
* To display source code tag information on a sidebar install
[tagbar](https://github.com/majutsushi/tagbar).
* For snippet features install:
[ultisnips](https://github.com/SirVer/ultisnips) or
[neosnippet](https://github.com/Shougo/neosnippet.vim).
* Screenshot color scheme is a slightly modified molokai: [fatih/molokai](https://github.com/fatih/molokai).
* For a better documentation viewer checkout: [go-explorer](https://github.com/garyburd/go-explorer).

## Usage

Many of the plugin's [features](#features) are enabled by default. There are no
additional settings needed. All usages and commands are listed in
`doc/vim-go.txt`. Note that help tags needs to be populated. Check your plugin
manager settings to generate the documentation (some do it automatically).
After that 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:

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

```vim
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:

```vim
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)
```

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

```vim
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

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

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

```vim
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`)

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

Rename the identifier under the cursor to a new name

```vim
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`.

### Location list navigation

All commands support collecting and displaying errors in Vim's location
  list.

Quickly navigate through these location lists with `:lne` for next error and `:lp` 
for previous.  You can also bind these to keys, for example:

```vim
map <C-n> :lne<CR>
map <C-m> :lp<CR>
```

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

By default syntax-highlighting for Functions, Methods and Structs is disabled.
To change it:
```vim
let g:go_highlight_functions = 1
let g:go_highlight_methods = 1
let g:go_highlight_structs = 1
let g:go_highlight_operators = 1
let g:go_highlight_build_constraints = 1
```

Enable goimports to automatically insert import paths instead of gofmt:

```vim
let g:go_fmt_command = "goimports"
```

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

```vim
let g:go_fmt_fail_silently = 1
```

Disable auto fmt on save:

```vim
let g:go_fmt_autosave = 0
```

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

```vim
let g:go_play_open_browser = 0
```

By default when `:GoInstallBinaries` is called, the binaries are installed to
`$GOBIN` or `$GOPATH/bin`. To change it:

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

## Using with Syntastic
Sometimes when using both `vim-go` and `syntastic` Vim will start lagging while saving and opening
files. The following fixes this:

```vim
let g:syntastic_go_checkers = ['golint', 'govet', 'errcheck']
let g:syntastic_mode_map = { 'mode': 'active', 'passive_filetypes': ['go'] }
```

## More info

Check out the [Wiki](https://github.com/fatih/vim-go/wiki) page for more information. It includes [Screencasts](https://github.com/fatih/vim-go/wiki/Screencasts), an [FAQ
section](https://github.com/fatih/vim-go/wiki/FAQ-Troubleshooting), and many other [various pieces](https://github.com/fatih/vim-go/wiki) of information.

## 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)
* [Contributors](https://github.com/fatih/vim-go/graphs/contributors) of vim-go

## License

The BSD 3-Clause License - see `LICENSE` for more details