make it compatible with vim-javascript

Author: crusoexia

after/syntax/javascript.vim

@@ -1,29 +1,22 @@
-echo "after javascript is in charge"
-
-if !exists("main_syntax")
-  if version < 600
-    syntax clear
-  elseif exists("b:current_syntax")
-    finish
-  endif
-  let main_syntax = 'javascript'
-endif
-
-"" Drop fold if it is set but VIM doesn't support it.
-let b:javascript_fold='true'
-if version < 600    " Don't support the old version
-  unlet! b:javascript_fold
-endif
-
-"" dollar sign is permittd anywhere in an identifier
-setlocal iskeyword+=$
-
-syntax sync fromstart
-syntax keyword jsLibrary        _ underscore
-syntax keyword jsLibrary        jQuery $
-syntax keyword jsLibrary        Backbone nextgroup=jsBackboneClass
-
-syntax match jsBackboneClass    /\v%(\.)\zs<%(Model|View|Collection|Events|Router)>/
+" Vim syntax file
+" This is a [vim-javascript](https://github.com/pangloss/vim-javascript)'s companion, 
+" which is used for highlight the javascript library keywords.
+"
+" Language:     JavaScript
+" Maintainer:   crusoexia
+" URL:          https://github.com/crusoexia/vim-javascript-lib
+
+syntax keyword  jsLibrary           _ underscore
+syntax keyword  jsLibrary           jQuery $
+syntax keyword  jsLibrary           Backbone nextgroup=jsBBoneAccessExpr
+syntax keyword  jsLibrary           angular
+syntax keyword  jsLibrary           jasmine
+
+syntax match    jsBBoneAccessExpr   /\./ contained nextgroup=jsBackboneClass
+syntax keyword  jsBackboneClass     Model View Collection Events Router History contained
+
+" Add to [vim-javascript](https://github.com/pangloss/vim-javascript) syntax groups.
+syntax cluster  jsExpression        add=jsLibrary
 
 if version >= 508 || !exists("did_javascript_lib_syn_inits")
   if version < 508
@@ -34,12 +27,7 @@ if version >= 508 || !exists("did_javascript_lib_syn_inits")
   endif
 
   HiLink jsLibrary              Constant
-  HiLink jsBackboneClass        Type
+  HiLink jsBackboneClass        Constant
 
   delcommand HiLink
 endif
-
-let b:current_syntax = "javascript"
-if main_syntax == 'javascript'
-  unlet main_syntax
-endif