Merge pull request jashkenas#2334 from michaelficarra/issue2333

fixes jashkenas#2333: fix prohibition of duplicate object properties

src/helpers.coffee

@@ -54,3 +54,8 @@ exports.del = (obj, key) ->
 
 # Gets the last item of an array(-like) object.
 exports.last = (array, back) -> array[array.length - (back or 0) - 1]
+
+# Typical Array::some
+exports.some = Array::some ? (fn) ->
+  return true for e in this when fn e
+  false

src/nodes.coffee

@@ -7,7 +7,7 @@
 {RESERVED, STRICT_PROSCRIBED} = require './lexer'
 
 # Import the helpers we plan to use.
-{compact, flatten, extend, merge, del, starts, ends, last} = require './helpers'
+{compact, flatten, extend, merge, del, starts, ends, last, some} = require './helpers'
 
 exports.extend = extend  # for parser
 
@@ -802,11 +802,26 @@ exports.Obj = class Obj extends Base
   compileNode: (o) ->
     props = @properties
     propNames = []
+    normalise = (s) -> switch s[0]
+      when '"' then s[1...-1].replace /\\"/g, '"'
+      when "'" then s[1...-1].replace /\\'/g, "'"
+    isDuplicate = (x) ->
+      mx = x.match /^['"]/
+      (y) ->
+        return true if y is x or +y is +x
+        my = y.match /^['"]/
+        if mx and my
+          return true if normalise(x) is normalise y
+        else if mx
+          return true if y is x[1...-1]
+        else if my
+          return true if x is y[1...-1]
+        false
     for prop in @properties
       prop = prop.variable if prop.isComplex()
       if prop?
         propName = prop.unwrapAll().value.toString()
-        if propName in propNames
+        if some.call propNames, isDuplicate propName
           throw SyntaxError "multiple object literal properties named \"#{propName}\""
         propNames.push propName
     return (if @front then '({})' else '{}') unless props.length

test/strict.coffee

@@ -57,9 +57,23 @@ test "octal escape sequences prohibited", ->
 
 
 test "duplicate property definitions in object literals are prohibited", ->
-  strict 'o = {x:1,x:1}'
+  strict 'o = {x:1, x:1}'
   strict 'x = 1; o = {x, x: 2}'
 
+test "#2333: more duplicate property prohibitions", ->
+  strict '{a:0, "a":0}'
+  strict "{'a':0, a:0}"
+  strict '{\'a\':0, "a":0}'
+  strict '{0:0, 0x0:0}'
+  strict '{0:0, "\\x30":0}'
+  strict '{.1:0, 0.1:0}'
+  strict '{.1:0, 1e-1:0}'
+  strict '{100:0, 1e2:0}'
+  strict '{"\\0":0, "\\x00":0}'
+  strict 'a = 0; {a, "a":0}'
+  strictOk '{0:0, "0x0":0}'
+  strictOk '{"a":0, "\'a\'":0}'
+
 test "duplicate formal parameters are prohibited", ->
   nonce = {}