Correctly highlight function bodies with an unnamed, generic function.

SamirTalwar · amadeus · commit bc60e0d0041c · 2017-08-25T15:37:08.000-07:00
Given the following JavaScript + Flow code:

    const foo = function&lt;T&gt;(x: T): void {
      // arbitrary, unrelated body
      while (true) {
        console.log(x);
      }
    }

The body won't be highlighted correctly; on my machine, it's mostly in red.

This seems to be caused by incorrectly parsing the `&lt;T&gt;` when the
function is unnamed. Not sure why it ends up highlighting everything in
one colour.

This commit fixes the problem. I might have missed somewhere; I looked
for `jsFuncArgs` and added it to the same places.
diff --git a/syntax/javascript.vim b/syntax/javascript.vim
@@ -164,7 +164,7 @@ syntax region  jsSpreadExpression   contained matchgroup=jsSpreadOperator      s
 syntax region  jsRestExpression     contained matchgroup=jsRestOperator        start=/\.\.\./ end=/[,)]\@=/
 syntax region  jsTernaryIf                    matchgroup=jsTernaryIfOperator   start=/?/  end=/\%(:\|[\}]\@=\)/  contains=@jsExpression extend skipwhite skipempty nextgroup=@jsExpression
 
-syntax match   jsGenerator            contained /\*/ skipwhite skipempty nextgroup=jsFuncName,jsFuncArgs
+syntax match   jsGenerator            contained /\*/ skipwhite skipempty nextgroup=jsFuncName,jsFuncArgs,jsFlowFunctionGroup
 syntax match   jsFuncName             contained /\<[a-zA-Z_$][0-9a-zA-Z_$]*\>/ skipwhite skipempty nextgroup=jsFuncArgs,jsFlowFunctionGroup
 syntax region  jsFuncArgExpression    contained matchgroup=jsFuncArgOperator start=/=/ end=/[,)]\@=/ contains=@jsExpression extend
 syntax match   jsFuncArgCommas        contained ','
@@ -176,10 +176,10 @@ syntax match   jsArrowFuncArgs  /\k\+\s*\%(=>\)\@=/ skipwhite contains=jsFuncArg
 " Matches a series of arguments surrounded in parens
 syntax match   jsArrowFuncArgs  /([^()]*)\s*\(=>\)\@=/ contains=jsFuncArgs skipempty skipwhite nextgroup=jsArrowFunction extend
 
-exe 'syntax match jsFunction /\<function\>/ skipwhite skipempty nextgroup=jsGenerator,jsFuncName,jsFuncArgs skipwhite '.(exists('g:javascript_conceal_function')       ? 'conceal cchar='.g:javascript_conceal_function : '')
-exe 'syntax match jsArrowFunction /=>/      skipwhite skipempty nextgroup=jsFuncBlock,jsCommentFunction               '.(exists('g:javascript_conceal_arrow_function') ? 'conceal cchar='.g:javascript_conceal_arrow_function : '')
-exe 'syntax match jsArrowFunction /()\s*\(=>\)\@=/   skipwhite skipempty nextgroup=jsArrowFunction                    '.(exists('g:javascript_conceal_noarg_arrow_function') ? 'conceal cchar='.g:javascript_conceal_noarg_arrow_function : '').(' contains=jsArrowFuncArgs')
-exe 'syntax match jsArrowFunction /_\s*\(=>\)\@=/    skipwhite skipempty nextgroup=jsArrowFunction                    '.(exists('g:javascript_conceal_underscore_arrow_function') ? 'conceal cchar='.g:javascript_conceal_underscore_arrow_function : '')
+exe 'syntax match jsFunction /\<function\>/ skipwhite skipempty nextgroup=jsGenerator,jsFuncName,jsFuncArgs,jsFlowFunctionGroup skipwhite '.(exists('g:javascript_conceal_function')       ? 'conceal cchar='.g:javascript_conceal_function : '')
+exe 'syntax match jsArrowFunction /=>/      skipwhite skipempty nextgroup=jsFuncBlock,jsCommentFunction                                   '.(exists('g:javascript_conceal_arrow_function') ? 'conceal cchar='.g:javascript_conceal_arrow_function : '')
+exe 'syntax match jsArrowFunction /()\s*\(=>\)\@=/   skipwhite skipempty nextgroup=jsArrowFunction                                        '.(exists('g:javascript_conceal_noarg_arrow_function') ? 'conceal cchar='.g:javascript_conceal_noarg_arrow_function : '').(' contains=jsArrowFuncArgs')
+exe 'syntax match jsArrowFunction /_\s*\(=>\)\@=/    skipwhite skipempty nextgroup=jsArrowFunction                                        '.(exists('g:javascript_conceal_underscore_arrow_function') ? 'conceal cchar='.g:javascript_conceal_underscore_arrow_function : '')
 
 " Classes
 syntax keyword jsClassKeyword           contained class
