nvim-go

A minimal implementation of Golang development plugin written in Lua for Neovim.

Introduction

Neovim (from v0.5) embeds a built-in Language Server Protocol (LSP) client. And Debug Adapter Protocol (DAP) are also brought into Neovim as a general debugger. With the power of them, we are able to easily turn Neovim into a powerful editor.

nvim-go is designed to collaborate with them, provides sufficient features, and leverages community toolchains to get Golang development done.

Features

• Auto format with :GoFormat (via goimports, gofmt, gofumpt and lsp) when saving.
• Run linters with :GoLint (via revive) automatically.
• Quickly test with :GoTest, :GoTestFunc, :GoTestFile and :GoTestAll. Generate test with :GoAddTest.
• Import packages with :GoGet and :GoImport.
• Modify struct tags with :GoAddTags, :GoRemoveTags, :GoClearTags, :GoAddTagOptions, :GoRemoveTagOptions and :GoClearTagOptions.
• Generates JSON models with :GoQuickType (via quicktype).
• Generate if err based on function return values with :GoIfErr (via iferr).

Screenshots

Recommended Features

This section can be regarded as a guide or common practice to develop with nvim-go, LSP (gopls) and DAP. If you are familiar with these tools or other equivalent, you may skip this chapter.

Language Server

Language server provides vital language features to make Golang development easy. We highly recommend you to use LSP client together with nvim-go.

1. Setup gopls with neovim/nvim-lspconfig.
2. Setup your favorite completion engine such as nvim-cmp.
3. Setup and map the following methods based on what you need:

• Declaration: vim.lsp.buf.declaration()
• Definition: vim.lsp.buf.definition() and vim.lsp.buf.type_definition()
• Implementation: vim.lsp.buf.implementation()
• Hover: vim.lsp.buf.hover()
• Signature: vim.lsp.buf.signature_help()
• References: vim.lsp.buf.reference()
• Symbols: vim.lsp.buf.document_symbol() and vim.lsp.buf.workspace_symbol()
• Rename: vim.lsp.buf.rename()
• Format: vim.lsp.buf.format(), also works with GoFormat.
• Diagnostic: vim.diagnostic will also show lint issues with Virtual Text, which runs go/analysis. You may disable auto_lint if this works well with your project.

For details of gopls, please refer to https://github.com/golang/tools/blob/master/gopls/doc/design/design.md#features.

Debugger

• nvim-dap

Installation

Prerequisites:

• Neovim (>= 0.7)
• npm (for quicktype)

Install with your favorite package manager:

" dependencies
use('nvim-lua/plenary.nvim')

" nvim-go
use('crispgm/nvim-go')

" (optional) if you enable nvim-notify
use('rcarriga/nvim-notify')

" (recommend) LSP config
use('neovim/nvim-lspconfig')

Finally, run :GoInstallBinaries after plugin installed.

Install quicktype with yarn or pnpm:

nvim-go install quicktype with npm by default, you may replace it with yarn or pnpm.

require('go').config.update_tool('quicktype', function(tool)
    tool.pkg_mgr = 'yarn'
end)

Usage

Setup

-- setup nvim-go
require('go').setup({})

-- setup lsp client
require('lspconfig').gopls.setup({})

Defaults

require('go').setup({
    -- notify: use nvim-notify
    notify = false,
    -- auto commands
    auto_format = true,
    auto_lint = true,
    -- linters: revive, errcheck, staticcheck, golangci-lint
    linter = 'revive',
    -- linter_flags: e.g., {revive = {'-config', '/path/to/config.yml'}}
    linter_flags = {},
    -- lint_prompt_style: qf (quickfix), vt (virtual text)
    lint_prompt_style = 'qf',
    -- formatter: goimports, gofmt, gofumpt, lsp
    formatter = 'goimports',
    -- maintain cursor position after formatting loaded buffer
    maintain_cursor_pos = false,
    -- test flags: -count=1 will disable cache
    test_flags = {'-v'},
    test_timeout = '30s',
    test_env = {},
    -- show test result with popup window
    test_popup = true,
    test_popup_auto_leave = false,
    test_popup_width = 80,
    test_popup_height = 10,
    -- test open
    test_open_cmd = 'edit',
    -- struct tags
    tags_name = 'json',
    tags_options = {'json=omitempty'},
    tags_transform = 'snakecase',
    tags_flags = {'-skip-unexported'},
    -- quick type
    quick_type_flags = {'--just-types'},
})

Manual

Display within Neovim with:

:help nvim-go

Advanced Configuration

Statusline Count

vim-airline:

function! LintIssuesCount()
    if exists('g:nvim_go#lint_issues_count')
        return g:nvim_go#lint_issues_count
    endif
endfunction
call airline#parts#define_function('nvim_go', 'LintIssuesCount')
call airline#parts#define_condition('nvim_go', '&filetype == "go"')
let g:airline_section_warning = airline#section#create_right(['nvim_go'])

lightline:

function! LintIssuesCount()
    if exists('g:nvim_go#lint_issues_count') && &filetype == 'go'
        return g:nvim_go#lint_issues_count
    endif
endfunction
let g:lightline = {
  \ 'colorscheme': 'wombat',
  \ 'active': {
  \   'left': [ [ 'mode', 'paste' ],
  \             [ 'readonly', 'filename', 'modified', 'lintcount' ] ]
  \ },
  \ 'component_function': {
  \   'lintcount': 'LintIssuesCount'
  \ },
  \ }

nvim-hardline:

require('hardline').setup({
    -- ...
    sections = {
        {
            class = 'error',
            item = function()
                if
                    vim.bo.filetype == 'go'
                    and vim.g['nvim_go#lint_issues_count'] ~= nil
                then
                    return vim.g['nvim_go#lint_issues_count']
                else
                    return ''
                end
            end,
        },
    -- ...
    }

Show Lint Issues without Focusing

augroup NvimGo
  autocmd!
  autocmd User NvimGoLintPopupPost wincmd p
augroup END

Or equivalently:

local NvimGo = vim.api.nvim_create_augroup("NvimGo", {
  clear = true,
})
vim.api.nvim_create_autocmd({ "User" }, {
  pattern = "NvimGoLintPopupPost",
  group = NvimGo,
  command = "wincmd p",
})

License

MIT