coc-snippets

Snippets solution for coc.nvim

Snippet preview requires neovim 0.4 or latest vim8

It's capable of:

• Load UltiSnips snippets.
• Load snipmate snippets.
• Load VSCode snippets from coc.nvim extensions.
• Load VSCode snippets from custom directories.
• Load VSCode snippets from ${workspaceFolder}/.vscode.
• Load UltiSnips snippets from configured folder.
• Load massCode snippets from running massCode application (disabled by default).
• Create massCode snippets through the snippets.editMassCodeSnippets command.
• Provide snippets as completion items.
• Provide expand and expandOrJump keymaps for snippet.
• Provide snippets list for edit snippet.
• Provide snippets.editSnippets command for edit user snippets of current filetype.

Note: some features of ultisnips and snipmate format snippets not supported, checkout Ultisnips features.

Why?

• Use same keys for jump placeholder.
• Nested snippet support.
• Always async, never slows you down.
• Preview snippet context in float window/popup.
• Improved match for complete items with TextEdit support.
• Edit snippets of current buffer by :CocList snippets.

Python support

Ultisnips provider needs pythonx support on (neo)vim, to check the feature exists, try:

:echo has('pythonx')

On neovim, run command:

:checkhealth

If it is not installed, run:

pip install pynvim

and make sure you have Python 3 provider for neovim installed.

On vim8, run command:

:pyx print(1)

in your vim, if it throws, it means your vim is not compiled with python support or the python dynamic lib required by vim is missing(or broken).

Note: some python code may require python feature that not supported by the python interpreter used by vim, error will throw on that case.

~Error will be shown when pythonx with (neo)vim can't work, fix pythonx support or disable ultisnips support by add "snippets.ultisnips.enable": false in your configuration file.~

Install

In your vim/neovim, run command:

:CocInstall coc-snippets

Examples

" Use <C-l> for trigger snippet expand.
imap <C-l> <Plug>(coc-snippets-expand)

" Use <C-j> for select text for visual placeholder of snippet.
vmap <C-j> <Plug>(coc-snippets-select)

" Use <C-j> for jump to next placeholder, it's default of coc.nvim
let g:coc_snippet_next = '<c-j>'

" Use <C-k> for jump to previous placeholder, it's default of coc.nvim
let g:coc_snippet_prev = '<c-k>'

" Use <C-j> for both expand and jump (make expand higher priority.)
imap <C-j> <Plug>(coc-snippets-expand-jump)

" Use <leader>x for convert visual selected code to snippet
xmap <leader>x  <Plug>(coc-convert-snippet)

Make <tab> used for trigger completion, completion confirm, snippet expand and jump like VSCode.

Note from coc.nvim 0.0.82, functions starts with coc#pum should be used for custom completion of coc.nvim.

inoremap <silent><expr> <TAB>
      \ coc#pum#visible() ? coc#_select_confirm() :
      \ coc#expandableOrJumpable() ? "\<C-r>=coc#rpc#request('doKeymap', ['snippets-expand-jump',''])\<CR>" :
      \ CheckBackspace() ? "\<TAB>" :
      \ coc#refresh()

function! CheckBackspace() abort
  let col = col('.') - 1
  return !col || getline('.')[col - 1]  =~# '\s'
endfunction

let g:coc_snippet_next = '<tab>'

Ultisnips features

Some ultisnips features are not supported:

• Position check of trigger option, including b, w and i.
• Execute vim, python and shell code in snippet.
• extends, priority and clearsnippets command in snippet file.
• Visual placeholder.
• Placeholder and variable transform.
• Expression snippet.
• Automatic trigger snippet.
• Context snippets.
• Support loading snipmate snippets.
• Replacement String, (:h UltiSnips-replacement-string), requires latest coc.nvim.
• Update python code block after change of placeholder.
• Execute shell code with custom shabang (will not support).
• Option m, trim all whitespaces from right side of snippet lines.
• Reformat snippet options, including t, s.
• All snippet actions including pre_expand, post_expand and jump (can't support).
• snip.expand_anon() and other properties with UltiSnips actions.

Note: snip.expand_anon expand the snippet in async manner by use timer when used with pre_expand and post_expand action, which means the state is lost in your python script (should only happens on some rare cases).

Note: python regex in snippet are converted to javascript regex, however, some regex patterns can't be supported by javascript, including (?x) (?s) \Z (?(id/name)yes-pattern|no-pattern).

Functions

• coc#expandable() return 1 when can do snippet expand.
• coc#jumpable() return 1 when snippet activated and can jump to next placeholder.
• coc#expandableOrJumpable() return 1 when can do snippet expand or can jump to next placeholder.

Key-mappings

Note you can't use noremap with <Plug> key-mappings.

• <Plug>(coc-convert-snippet) Create new snippet with current selected text, visual mode only.
• <Plug>(coc-snippets-expand) Expand snippet with current inserted text, insert mode only.
• <Plug>(coc-snippets-expand-async) None block variant of <Plug>(coc-snippets-expand).
• <Plug>(coc-snippets-expand-jump) Expand snippet or jump to next placeholder of current snippet when possible, insert mode only.
• <Plug>(coc-snippets-expand-jump-async) None block variant of <Plug>(coc-snippets-expand-jump).
• <Plug>(coc-snippets-select) Remove selected text and save to g:coc_selected_text which will replace $VISUAL on next snippet expand.

Commands

• Use :CocList snippets to open snippets list used by current buffer.
• Use :CocCommand snippets.openSnippetFiles to choose and open a snippet file that used by current document.
• Use :CocCommand snippets.editSnippets to edit user's ultisnips snippets of current document filetype.
• Use :CocCommand snippets.openOutput to open output channel of snippets.
• Use :CocCommand snippets.addFiletypes to add additional filetypes of current buffer.

Use b:coc_snippets_filetypes to add additional filetypes on buffer create.

Options

• snippets.priority: Completion source priority of snippets. Default: 90
• snippets.editSnippetsCommand: Open command used for snippets.editSnippets command, use coc.preferences.jumpCommand by default. Default: ""
• snippets.trace: Trace level of snippets channel, used for textmate snippets only. Default: "error" Valid options: ["error","verbose"]
• snippets.excludePatterns: List of minimatch patterns for filepath to exclude, support expand homedir and environment variables. Default: []
• snippets.loadFromExtensions: Enable load snippets from extensions. Default: true
• snippets.textmateSnippetsRoots: List of directories that contains textmate/VSCode snippets to load. Default: []
• snippets.loadVSCodeProjectSnippets: Load code snippets in folder ${workspaceFolder}/.vscode Default: true
• snippets.extends: Configure filetypes to inherit with, ex: {"cpp": ["c"], "javascriptreact": ["javascript"]} Default: {}
• snippets.userSnippetsDirectory: Directory that contains custom user ultisnips snippets, use ultisnips in extension root of coc.nvim by default. Default: ""
• snippets.shortcut: Shortcut in completion menu. Default: "S"
• snippets.triggerCharacters: Trigger characters for trigger snippets completion. Default: []
• snippets.disableSyntaxes: Disable snippets completion when syntax name matches one of disabled syntaxes. Default: []
• snippets.execContext: Execute a snippet's context (if it exists) to check if the snippet should be shown in completion menu Default: false
• snippets.autoTrigger: Enable trigger auto trigger snippet after type character. Default: true
• snippets.ultisnips.enable: Enable load snippets from ultisnips folders. Default: true
• snippets.ultisnips.pythonPrompt: Show prompt for user when python not supported on vim. Default: true
• snippets.ultisnips.trace: Trace verbose snippet information. Default: false
• snippets.ultisnips.directories: Directories that searched for ultisnips snippet files, could be directory as subfolder in $runtimepath or absolute paths. Default: ["UltiSnips"]
• snippets.massCode.enable: Enable load snippets from MassCode. Default: false
• snippets.massCode.host: Http host of MassCode. Default: "localhost"
• snippets.massCode.port: Http port of MassCode. Default: 3033
• snippets.massCode.trace: Trace verbose snippet information. Default: false
• snippets.snipmate.enable: Load snipmate snippets from snippets directory in runtimepath. Default: true
• snippets.snipmate.trace: Trace verbose snippet information. Default: false
• snippets.snipmate.author: Author name used for g:snips_author Default: ""

F.A.Q

Q: How to add snippet filetypes on buffer create?

A: Use autocmd like: autocmd BufRead *.md let b:coc_snippets_filetypes = ['tex']

Q: How to trigger snippets completion when type special characters?

A: Use configuration like: "snippets.triggerCharacters": ["'"].

Q: How to check if a snippet successfully loaded?

A: Use command :CocCommand workspace.showOutput snippets

Q: Some ultisnips snippet not works as expected.

A: Reformat after change of placeholder feature can't be supported for now, and some regex pattern can't be converted to javascript regex pattern, so the snippet can be failed to load.

Q: Where to get snippets?

A: One solution is install honza/vim-snippets which is widely used. To create snippets yourself:

• For Ultisnips, create ${filetype}.snippets in "snippets.ultisnips.directories"
• For snipmate snippets, create ${filetype}.snippets in snippets folder under your vim's runtimepath.
• For VSCode snippets, create ${filetype}.json in your "snippets.textmateSnippetsRoots".

Q: Get error message ModuleNotFoundError: No module named 'vimsnippets'

A: Make sure honza/vim-snippets in your vim's &runtimepath.

Q: Do I need to install Ultisnips.

A: No! This extension is designed to work with or without Ultisnips, you can still install Ultisnips, but this extension would not run any code or read configuration from it.

Q: How to check jumpable or expandable at current position.

A: Use functions provided by coc.nvim: coc#expandable() coc#jumpable() and coc#expandableOrJumpable().

Q: How could I add custom UltiSnips snippets.

A: You can create snippet files in folder: $VIMCONFIG/coc/ultisnips, use command :CocCommand snippets.editSnippets to open user snippet of current filetype.

Supporting

If you like this extension, consider supporting me on Patreon or PayPal:

License

MIT