First pass at handling lamba arguments

Author: amadeus

syntax/javascript.vim

@@ -192,7 +192,7 @@ endif "DOM/HTML/CSS
 "" end DOM/HTML/CSS specified things
 
 "" Code blocks
-syntax cluster jsExpression contains=jsComment,jsLineComment,jsBlockComment,jsTaggedTemplate,jsTemplateString,jsStringD,jsStringS,jsRegexpString,jsNumber,jsFloat,jsThis,jsStatic,jsSuper,jsOperator,jsBooleanTrue,jsBooleanFalse,jsNull,jsFunction,jsArrowFunction,jsGlobalObjects,jsExceptions,jsFutureKeys,jsDomErrNo,jsDomNodeConsts,jsHtmlEvents,jsDotNotation,jsBracket,jsParen,jsBlock,jsFuncCall,jsUndefined,jsNan,jsKeyword,jsStorageClass,jsPrototype,jsBuiltins,jsNoise,jsCommonJS,jsAssignmentExpr,jsImportContainer,jsExportContainer,jsArgsObj,jsDecorator,jsAsyncKeyword,jsClassDefinition
+syntax cluster jsExpression contains=jsComment,jsLineComment,jsBlockComment,jsTaggedTemplate,jsTemplateString,jsStringD,jsStringS,jsRegexpString,jsNumber,jsFloat,jsThis,jsStatic,jsSuper,jsOperator,jsBooleanTrue,jsBooleanFalse,jsNull,jsFunction,jsArrowFunction,jsGlobalObjects,jsExceptions,jsFutureKeys,jsDomErrNo,jsDomNodeConsts,jsHtmlEvents,jsDotNotation,jsBracket,jsParen,jsBlock,jsFuncCall,jsUndefined,jsNan,jsKeyword,jsStorageClass,jsPrototype,jsBuiltins,jsNoise,jsCommonJS,jsAssignmentExpr,jsImportContainer,jsExportContainer,jsArgsObj,jsDecorator,jsAsyncKeyword,jsClassDefinition,jsArrowFunction,jsArrowFuncArgs
 syntax cluster jsAll        contains=@jsExpression,jsLabel,jsConditional,jsRepeat,jsReturn,jsStatement,jsTernaryIf,jsException
 syntax region  jsBracket    matchgroup=jsBrackets     start="\[" end="\]" contains=@jsAll,jsParensErrB,jsParensErrC,jsBracket,jsParen,jsBlock,@htmlPreproc fold
 syntax region  jsParen      matchgroup=jsParens       start="("  end=")"  contains=@jsAll,jsOf,jsParensErrA,jsParensErrC,jsParen,jsBracket,jsBlock,@htmlPreproc fold
@@ -214,7 +214,7 @@ if main_syntax == "javascript"
 endif
 
 exe 'syntax match jsFunction /\<function\>/ nextgroup=jsGenerator,jsFuncName,jsFuncArgs skipwhite '.(exists('g:javascript_conceal_function') ? 'conceal cchar='.g:javascript_conceal_function : '')
-exe 'syntax match jsArrowFunction /=>/ skipwhite skipempty nextgroup=jsFuncBlock contains=jsFuncBraces '.(exists('g:javascript_conceal_arrow_function') ? 'conceal cchar='.g:javascript_conceal_arrow_function : '')
+exe 'syntax match jsArrowFunction /=>/ skipwhite nextgroup=jsFuncBlock contains=jsFuncBraces '.(exists('g:javascript_conceal_arrow_function') ? 'conceal cchar='.g:javascript_conceal_arrow_function : '')
 
 syntax match   jsGenerator       contained '\*' nextgroup=jsFuncName skipwhite
 syntax match   jsFuncName        contained /\<[a-zA-Z_$][0-9a-zA-Z_$]*/ nextgroup=jsFuncArgs skipwhite
@@ -223,6 +223,11 @@ syntax match   jsFuncArgCommas   contained ','
 syntax match   jsFuncArgRest     contained /\%(\.\.\.[a-zA-Z_$][0-9a-zA-Z_$]*\))/ contains=jsFuncArgRestDots
 syntax match   jsFuncArgRestDots contained /\.\.\./
 
+" Matches a single keyword argument with no parens
+syntax match   jsArrowFuncArgs  /\(\k\)\+\s\+\(=>\)\@=/ skipwhite contains=jsFuncArgs extend
+" Matches a series of arguments surrounded in parens
+syntax match   jsArrowFuncArgs  /(\(\k\|,\|\s\|\n\)*)\s\+\(=>\)\@=/ skipwhite contains=jsFuncArgs extend
+
 syntax keyword jsClassKeywords extends class contained
 syntax match   jsClassNoise /\./ contained
 syntax keyword jsClassMethodDefinitions get set static contained nextgroup=jsFuncName skipwhite skipempty