Update

syntax/vue.vim

@@ -10,6 +10,11 @@ if exists("b:current_syntax")
   finish
 endif
 
+" Convert deprecated variable to new one
+if exists('g:vue_disable_pre_processors') && g:vue_disable_pre_processors
+  let g:vue_pre_processors = []
+endif
+
 runtime! syntax/html.vim
 syntax clear htmlTagName
 syntax match htmlTagName contained "\<[a-zA-Z0-9:-]*\>"
@@ -21,47 +26,57 @@ function! s:attr(name, value)
   return a:name . '=\("\|''\)[^\1]*' . a:value . '[^\1]*\1'
 endfunction
 
-""
-" Check whether a syntax file for a given {language} exists.
-function! s:syntax_available(language)
-  return !empty(globpath(&runtimepath, 'syntax/' . a:language . '.vim'))
+function! s:should_register(language, start_pattern)
+  " Check whether a syntax file for {language} exists
+  if empty(globpath(&runtimepath, 'syntax/' . a:language . '.vim'))
+    return 0
+  endif
+
+  if exists('g:vue_pre_processors')
+    if type(g:vue_pre_processors) == v:t_list
+      return index(g:vue_pre_processors, s:language.name) != -1
+    elseif g:vue_pre_processors is# 'detect_on_enter'
+      return search(a:start_pattern, 'n') != 0
+    endif
+  endif
+
+  return 1
 endfunction
 
-""
-" Register {language} for a given {tag}. If [attr_override] is given and not
-" empty, it will be used for the attribute pattern.
-function! s:register_language(language, tag, ...)
-  let attr_override = a:0 ? a:1 : ''
-  let attr = !empty(attr_override) ? attr_override : s:attr('lang', a:language)
+let s:languages = [
+      \ {'name': 'less',       'tag': 'style'},
+      \ {'name': 'pug',        'tag': 'template', 'attr_pattern': s:attr('lang', '\%(pug\|jade\)')},
+      \ {'name': 'slm',        'tag': 'template'},
+      \ {'name': 'handlebars', 'tag': 'template'},
+      \ {'name': 'haml',       'tag': 'template'},
+      \ {'name': 'typescript', 'tag': 'script', 'attr_pattern': '\%(lang=\("\|''\)[^\1]*\(ts\|typescript\)[^\1]*\1\|ts\)'},
+      \ {'name': 'coffee',     'tag': 'script'},
+      \ {'name': 'stylus',     'tag': 'style'},
+      \ {'name': 'sass',       'tag': 'style'},
+      \ {'name': 'scss',       'tag': 'style'},
+      \ ]
 
-  if s:syntax_available(a:language)
-    execute 'syntax include @' . a:language . ' syntax/' . a:language . '.vim'
+for s:language in s:languages
+  let s:attr_pattern = has_key(s:language, 'attr_pattern') ? s:language.attr_pattern : s:attr('lang', s:language.name)
+  let s:start_pattern = '<' . s:language.tag . '\>\_[^>]*' . s:attr_pattern . '\_[^>]*>'
+
+  if s:should_register(s:language.name, s:start_pattern)
+    execute 'syntax include @' . s:language.name . ' syntax/' . s:language.name . '.vim'
     unlet! b:current_syntax
-    execute 'syntax region vue_' . a:language
+    execute 'syntax region vue_' . s:language.name
           \ 'keepend'
-          \ 'start=/<' . a:tag . '\>\_[^>]*' . attr . '\_[^>]*>/'
-          \ 'end="</' . a:tag . '>"me=s-1'
-          \ 'contains=@' . a:language . ',vueSurroundingTag'
+          \ 'start=/' . s:start_pattern . '/'
+          \ 'end="</' . s:language.tag . '>"me=s-1'
+          \ 'contains=@' . s:language.name . ',vueSurroundingTag'
           \ 'fold'
   endif
-endfunction
-
-if !exists("g:vue_disable_pre_processors") || !g:vue_disable_pre_processors
-  call s:register_language('less', 'style')
-  call s:register_language('pug', 'template', s:attr('lang', '\%(pug\|jade\)'))
-  call s:register_language('slm', 'template')
-  call s:register_language('handlebars', 'template')
-  call s:register_language('haml', 'template')
-  call s:register_language('typescript', 'script', '\%(lang=\("\|''\)[^\1]*\(ts\|typescript\)[^\1]*\1\|ts\)')
-  call s:register_language('coffee', 'script')
-  call s:register_language('stylus', 'style')
-  call s:register_language('sass', 'style')
-  call s:register_language('scss', 'style')
-endif
+endfor
 
 syn region  vueSurroundingTag   contained start=+<\(script\|style\|template\)+ end=+>+ fold contains=htmlTagN,htmlString,htmlArg,htmlValue,htmlTagError,htmlEvent
 syn keyword htmlSpecialTagName  contained template
 syn keyword htmlArg             contained scoped ts
 syn match   htmlArg "[@v:][-:.0-9_a-z]*\>" contained
 
+syntax sync fromstart
+
 let b:current_syntax = "vue"