diff --git a/grammars/javascript.cson b/grammars/javascript.cson
index 5572d851..6a3b81e8 100644
--- a/grammars/javascript.cson
+++ b/grammars/javascript.cson
@@ -297,7 +297,7 @@
   {
     # [async] function [name](params)
     # function* name(params) – generator function declaration
-    'begin': '(?=(\\basync\\b\\s*)?\\bfunction\\b)'
+    'begin': '(?=(\\basync\\b\\s*)?\\bfunction\\b(?!\\s*:))'
     'end': '(?<=})'
     'patterns': [
       {
@@ -591,7 +591,7 @@
       (?<=})|
       ((?!
         \\s*{|
-        \\G[\\w$]+:|
+        \\G[\\w$]+\\s*:|
         \\s*/\\*|\\s*//
       )(?=\\s*\\S))
     '''
diff --git a/spec/javascript-spec.coffee b/spec/javascript-spec.coffee
index 68f0b29c..4c7bee56 100644
--- a/spec/javascript-spec.coffee
+++ b/spec/javascript-spec.coffee
@@ -1084,6 +1084,23 @@ describe "Javascript grammar", ->
       expect(tokens[7]).toEqual value: 'foo', scopes: ['source.js', 'meta.function.json.js', 'entity.name.function.js']
       expect(tokens[8]).toEqual value: '(', scopes: ['source.js', 'meta.function.json.js', 'meta.parameters.js', 'punctuation.definition.parameters.begin.bracket.round.js']
 
+      {tokens} = grammar.tokenizeLine('function : a => a')
+      expect(tokens[0]).toEqual value: 'function', scopes: ['source.js', 'meta.function.arrow.json.js', 'entity.name.function.js']
+      expect(tokens[2]).toEqual value: ':', scopes: ['source.js', 'meta.function.arrow.json.js', 'keyword.operator.assignment.js']
+      expect(tokens[4]).toEqual value: 'a', scopes: ['source.js', 'meta.function.arrow.json.js', 'meta.parameters.js', 'variable.parameter.function.js']
+      expect(tokens[6]).toEqual value: '=>', scopes: ['source.js', 'meta.function.arrow.json.js', 'storage.type.function.arrow.js']
+      expect(tokens[7]).toEqual value: ' a', scopes: ['source.js']
+
+      {tokens} = grammar.tokenizeLine('"func": a => a')
+      expect(tokens[1]).toEqual value: 'func', scopes: ['source.js', 'meta.function.arrow.json.js', 'string.quoted.double.js', 'entity.name.function.js']
+      expect(tokens[3]).toEqual value: ':', scopes: ['source.js', 'meta.function.arrow.json.js', 'keyword.operator.assignment.js']
+      expect(tokens[5]).toEqual value: 'a', scopes: ['source.js', 'meta.function.arrow.json.js', 'meta.parameters.js', 'variable.parameter.function.js']
+      expect(tokens[7]).toEqual value: '=>', scopes: ['source.js', 'meta.function.arrow.json.js', 'storage.type.function.arrow.js']
+      expect(tokens[8]).toEqual value: ' a', scopes: ['source.js']
+
+      {tokens} = grammar.tokenizeLine('"func" : a => a')
+      expect(tokens[8]).toEqual value: '=>', scopes: ['source.js', 'meta.function.arrow.json.js', 'storage.type.function.arrow.js']
+
     it "tokenizes generator functions", ->
       {tokens} = grammar.tokenizeLine('function* foo(){}')
       expect(tokens[0]).toEqual value: 'function', scopes: ['source.js', 'meta.function.js', 'storage.type.function.js']