vim-svelte-plugin

Vim syntax and indent plugin for .svelte files. Forked from vim-vue-plugin.

Installation

This plugin works if it has set filetype to svelte. Please stay up to date. Feel free to open an issue or pull request.

How it works

It combines HTML, CSS and JavaScript syntax and indent in one file.

Supports

• Svelte directives.

• Less/Sass/Scss, Pug with vim-pug, Coffee with vim-coffee-script, TypeScript with typescript-vim or yats.vim.^

  Relative plugins need to be installed.

• A builtin foldexpr foldmethod.^

• emmet-vim HTML/CSS/JavaScript filetype detection.

^: see Configuration for details.

Configuration

Set global variable to 1 to enable or 0 to disable. Ex:

let g:vim_svelte_plugin_load_full_syntax = 1

*: Vim may be slow if the feature is enabled. Find a balance between syntax highlight and speed. By the way, custom syntax can be added in ~/.vim/syntax or $VIM/vimfiles/syntax.

Note

• filetype is set to svelte so autocmds and other custom settings for javascript have to be manually enabled for svelte.
• g:vim_svelte_plugin_load_full_syntax applies to HTML/Sass/Less.
• See https://svelte.dev/docs#svelte_preprocess for how to use Less/Sass/Pug... in svelte.

Neovim & Treesiter

For css syntax highlighting you will need the css language parser for Treesiter. You can install it like so:

:TSInstall css

Context based behavior

As there are more than one language in .svelte file, the different behaviors like mapping, completion, and local options may be expected according to tags or subtypes(current language type).

This plugin provides functions to get the tag/subtype where the cursor is in.

• GetSvelteTag() => String: Return value is one of 'template', 'script', 'style'.

  " Example
  autocmd FileType svelte inoremap <buffer><expr> : InsertColon()
  
  function! InsertColon()
    let tag = GetSvelteTag()
    return tag == 'template' ? ':' : ': '
  endfunction
  

• GetSvelteSubtype() => String: Return value is one of 'html', 'javascript', 'css', 'scss', ....

• OnChangeSvelteSubtype(subtype): An event listener that is called when subtype changes.

  You can also define an event listener function OnChangeSvelteSubtype(subtype) in your vimrc to get the subtype and set its local options whenever it changes.

  " Example: set local options based on subtype
  function! OnChangeSvelteSubtype(subtype)
    echom 'Subtype is '.a:subtype
    if empty(a:subtype) || a:subtype == 'html'
      setlocal commentstring=<!--%s-->
      setlocal comments=s:<!--,m:\ \ \ \ ,e:-->
    elseif a:subtype =~ 'css'
      setlocal comments=s1:/*,mb:*,ex:*/ commentstring&
    else
      setlocal commentstring=//%s
      setlocal comments=sO:*\ -,mO:*\ \ ,exO:*/,s1:/*,mb:*,ex:*/,://
    endif
  endfunction
  

emmet-vim

Currently emmet-vim works regarding your HTML/CSS/JavaScript emmet settings, but it depends on how emmet-vim gets filetype and may change in the future. Feel free to report an issue if any problem appears.

Avoid overload

Since there are many sub languages included, most delays come from syntax files overload. A variable named b:current_loading_main_syntax is set to svelte which can be used as loading condition if you'd like to manually find and modify the syntax files causing overload.

For example, the builtin syntax sass.vim and less.vim in vim8.1 runtime always load css.vim which this plugin already loads. It can be optimized like

- runtime! syntax/css.vim
+ if !exists("b:current_loading_main_syntax")
+   runtime! syntax/css.vim
+ endif

See also

• vim-svelte-theme svelte syntax color
• vim-vue-plugin
• mxw/vim-jsx

License

This plugin is under The Unlicense. Other than this, lib/indent/* files are extracted from vim runtime.