Pass through octal and binary literals as-is

See coffeescript6/discuss#45

src/lexer.coffee

@@ -191,8 +191,10 @@ exports.Lexer = class Lexer
   # Be careful not to interfere with ranges-in-progress.
   numberToken: ->
     return 0 unless match = NUMBER.exec @chunk
+
     number = match[0]
     lexedLength = number.length
+
     if /^0[BOX]/.test number
       @error "radix prefix in '#{number}' must be lowercase", offset: 1
     else if /E/.test(number) and not /^0x/.test number
@@ -202,14 +204,12 @@ exports.Lexer = class Lexer
       @error "decimal literal '#{number}' must not be prefixed with '0'", length: lexedLength
     else if /^0\d+/.test number
       @error "octal literal '#{number}' must be prefixed with '0o'", length: lexedLength
-    if octalLiteral = /^0o([0-7]+)/.exec number
-      numberValue = parseInt(octalLiteral[1], 8)
-      number = "0x#{numberValue.toString 16}"
-    else if binaryLiteral = /^0b([01]+)/.exec number
-      numberValue = parseInt(binaryLiteral[1], 2)
-      number = "0x#{numberValue.toString 16}"
-    else
+
+    numberValue = number
+
+    unless /^(0o[0-7]+)/.test(number) or /^(0b[01]+)/.test(number)
       numberValue = parseFloat(number)
+
     tag = if numberValue is Infinity then 'INFINITY' else 'NUMBER'
     @token tag, number, 0, lexedLength
     lexedLength

test/numbers.coffee

@@ -13,9 +13,26 @@
 # Binary Integer Literals
 # Binary notation is understood as would be decimal notation.
 
+toJS = (str) ->
+  CoffeeScript.compile str, bare: yes
+  .replace /^\s+|\s+$/g, '' # Trim leading/trailing whitespace
+
 test "Parser recognises binary numbers", ->
   eq 4, 0b100
 
+test "Binary literals are compiled to binary literals", ->
+  input = """
+  a = 0b100
+  """
+
+  output = """
+  var a;
+
+  a = 0b100;
+  """
+
+  eq toJS(input), output
+
 # Decimal Integer Literals
 
 test "call methods directly on numbers", ->
@@ -24,6 +41,32 @@ test "call methods directly on numbers", ->
 
 eq -1, 3 -4
 
+test "Decimal literals are compiled to decimal literals", ->
+  input = """
+  a = 10
+  """
+
+  output = """
+  var a;
+
+  a = 10;
+  """
+
+  eq toJS(input), output
+
+test "Decimal literals are compiled to decimal literals", ->
+  input = """
+  a = 10.1
+  """
+
+  output = """
+  var a;
+
+  a = 10.1;
+  """
+
+  eq toJS(input), output
+
 #764: Numbers should be indexable
 eq Number::toString, 42['toString']
 
@@ -66,6 +109,19 @@ test "Python-style octal literal notation '0o777'", ->
   eq Number::toString, 0o777['toString']
   eq Number::toString, 0o777.toString
 
+test "Octal literals are compiled to octal literals", ->
+  input = """
+  a = 0o123
+  """
+
+  output = """
+  var a;
+
+  a = 0o123;
+  """
+
+  eq toJS(input), output
+
 test "#2060: Disallow uppercase radix prefixes and exponential notation", ->
   for char in ['b', 'o', 'x', 'e']
     program = "0#{char}0"