diff --git a/tests/tests.js b/tests/tests.js
index 63e093061c32..57df02a7b2c4 100644
--- a/tests/tests.js
+++ b/tests/tests.js
@@ -4284,6 +4284,178 @@
   });
 }).call(this);
 
+// Generated by LiveScript 1.3.1
+(function(){
+  var eq, toString$ = {}.toString;
+  QUnit.module('ES6');
+  eq = strictEqual;
+  test('String#replace regression', function(){
+    var instance, e;
+    ok(toString$.call(''.replace).slice(8, -1) === 'Function', 'String#replace is function');
+    eq(''.replace.length, 2, 'String#replace length is 2');
+    ok(/native code/.test(''.replace), 'looks like native');
+    if ('name' in ''.replace) {
+      eq(''.replace.name, 'replace', 'String#replace is "replace" (can fail if compressed)');
+    }
+    instance = Object(true);
+    instance.replace = String.prototype.replace;
+    eq(instance.replace(true, 1), '1', 'S15.5.4.11_A1_T1');
+    instance = Object(false);
+    instance.replace = String.prototype.replace;
+    eq(instance.replace(false, void 8), 'undefined', 'S15.5.4.11_A1_T2');
+    eq('gnulluna'.replace(null, function(a1, a2, a3){
+      return a2 + '';
+    }), 'g1una', 'S15.5.4.11_A1_T4');
+    eq('gnulluna'.replace(null, function(){}), 'gundefineduna', 'S15.5.4.11_A1_T5');
+    eq(Object('undefined').replace(void 8, function(){
+      return arguments[1] + 42;
+    }), '42', 'S15.5.4.11_A1_T6');
+    eq('undefined'.replace('e', void 8), 'undundefinedfined', 'S15.5.4.11_A1_T7');
+    eq(String({
+      toString: function(){}
+    }).replace(/e/g, void 8), 'undundefinedfinundefinedd', 'S15.5.4.11_A1_T8');
+    eq(new String({
+      valueOf: function(){},
+      toString: void 8
+    }).replace(function(){}(), function(a1, a2, a3){
+      return a1 + a2 + a3;
+    }), 'undefined0undefined', 'S15.5.4.11_A1_T9');
+    eq('ABB\u0041BABAB'.replace({
+      toString: function(){
+        return '\u0041B';
+      }
+    }, function(){}), 'undefinedBABABAB', 'S15.5.4.11_A1_T10');
+    try {
+      'ABB\u0041BABAB'.replace({
+        toString: function(){
+          throw 'insearchValue';
+        }
+      }, {
+        toString: function(){
+          throw 'inreplaceValue';
+        }
+      });
+      ok(false, 'S15.5.4.11_A1_T11 #1 lead to throwing exception');
+    } catch (e$) {
+      e = e$;
+      eq(e, 'insearchValue', 'S15.5.4.11_A1_T11 #2');
+    }
+    try {
+      Object('ABB\u0041BABAB').replace({
+        toString: function(){
+          return {};
+        },
+        valueOf: function(){
+          throw 'insearchValue';
+        }
+      }, {
+        toString: function(){
+          throw 'inreplaceValue';
+        }
+      });
+      ok(false, 'S15.5.4.11_A1_T12 #1 lead to throwing exception');
+    } catch (e$) {
+      e = e$;
+      eq(e, 'insearchValue', 'S15.5.4.11_A1_T12 #2');
+    }
+    try {
+      'ABB\u0041BABAB\u0031BBAA'.replace({
+        toString: function(){
+          return {};
+        },
+        valueOf: function(){
+          throw 'insearchValue';
+        }
+      }, {
+        toString: function(){
+          return 1;
+        }
+      });
+      ok(false, 'S15.5.4.11_A1_T13 #1 lead to throwing exception');
+    } catch (e$) {
+      e = e$;
+      eq(e, 'insearchValue', 'S15.5.4.11_A1_T13 #2');
+    }
+    eq('ABB\u0041BABAB\u0037\u0037BBAA'.replace(new RegExp('77'), 1), 'ABBABABAB\u0031BBAA', 'S15.5.4.11_A1_T14');
+    instance = Object(1100.00777001);
+    instance.replace = String.prototype.replace;
+    try {
+      instance.replace({
+        toString: function(){
+          return /77/;
+        }
+      }, 1);
+      ok(false, 'S15.5.4.11_A1_T15 #1 lead to throwing exception');
+    } catch (e$) {
+      e = e$;
+      ok(e instanceof TypeError, 'S15.5.4.11_A1_T15 #2');
+    }
+    instance = Object(1100.00777001);
+    instance.replace = String.prototype.replace;
+    try {
+      instance.replace(/77/, {
+        toString: function(){
+          return function(a1, a2, a3){
+            return a2 + 'z';
+          };
+        }
+      });
+      ok(false, 'S15.5.4.11_A1_T16 #1 lead to throwing exception');
+    } catch (e$) {
+      e = e$;
+      ok(e instanceof TypeError, 'S15.5.4.11_A1_T16 #2');
+    }
+    eq('asdf'.replace(RegExp('', 'g'), '1'), '1a1s1d1f1', 'S15.5.4.11_A1_T17');
+    eq('She sells seashells by the seashore.'.replace(/sh/g, 'sch'), 'She sells seaschells by the seaschore.', 'S15.5.4.11_A2_T1');
+    eq('She sells seashells by the seashore.'.replace(/sh/g, '$$sch'), 'She sells sea$schells by the sea$schore.', 'S15.5.4.11_A2_T2');
+    eq('She sells seashells by the seashore.'.replace(/sh/g, '$&sch'), 'She sells seashschells by the seashschore.', 'S15.5.4.11_A2_T3');
+    eq('She sells seashells by the seashore.'.replace(/sh/g, '$`sch'), 'She sells seaShe sells seaschells by the seaShe sells seashells by the seaschore.', 'S15.5.4.11_A2_T4');
+    eq('She sells seashells by the seashore.'.replace(/sh/g, "$'sch"), 'She sells seaells by the seashore.schells by the seaore.schore.', 'S15.5.4.11_A2_T5');
+    eq('She sells seashells by the seashore.'.replace(/sh/, 'sch'), 'She sells seaschells by the seashore.', 'S15.5.4.11_A2_T6');
+    eq('She sells seashells by the seashore.'.replace(/sh/, '$$sch'), 'She sells sea$schells by the seashore.', 'S15.5.4.11_A2_T7');
+    eq('She sells seashells by the seashore.'.replace(/sh/, '$&sch'), 'She sells seashschells by the seashore.', 'S15.5.4.11_A2_T8');
+    eq('She sells seashells by the seashore.'.replace(/sh/, '$`sch'), 'She sells seaShe sells seaschells by the seashore.', 'S15.5.4.11_A2_T9');
+    eq('She sells seashells by the seashore.'.replace(/sh/, "$'sch"), 'She sells seaells by the seashore.schells by the seashore.', 'S15.5.4.11_A2_T10');
+    eq('uid=31'.replace(/(uid=)(\d+)/, '$1115'), 'uid=115', 'S15.5.4.11_A3_T1');
+    eq('uid=31'.replace(/(uid=)(\d+)/, '$11A15'), 'uid=1A15', 'S15.5.4.11_A3_T3');
+    eq('abc12 def34'.replace(/([a-z]+)([0-9]+)/, function(){
+      return arguments[2] + arguments[1];
+    }), '12abc def34', 'S15.5.4.11_A4_T1');
+    eq('aaaaaaaaaa,aaaaaaaaaaaaaaa'.replace(/^(a+)\1*,\1+$/, '$1'), 'aaaaa', 'S15.5.4.11_A5_T1');
+  });
+  test('RegExp#@@replace', function(){
+    ok(toString$.call(/./[Symbol.replace]).slice(8, -1) === 'Function', 'RegExp#@@replace is function');
+    eq(/./[Symbol.replace].length, 2, 'RegExp#@@replace length is 2');
+    eq(/([a-z]+)([0-9]+)/[Symbol.replace]('abc12 def34', function(){
+      return arguments[2] + arguments[1];
+    }), '12abc def34');
+  });
+  test('@@replace logic', function(){
+    var O, ref$, re;
+    O = (ref$ = {}, ref$[Symbol.replace] = function(a, b){
+      return {
+        a: a,
+        b: b
+      };
+    }, ref$);
+    eq('qwe'.replace(O, 42).a, 'qwe');
+    eq('qwe'.replace(O, 42).b, 42);
+    eq(''.replace.call(123, O, 42).a, '123');
+    eq(''.replace.call(123, O, 42).b, 42);
+    re = /./;
+    re[Symbol.replace] = function(a, b){
+      return {
+        a: a,
+        b: b
+      };
+    };
+    eq('qwe'.replace(re, 42).a, 'qwe');
+    eq('qwe'.replace(re, 42).b, 42);
+    eq(''.replace.call(123, re, 42).a, '123');
+    eq(''.replace.call(123, re, 42).b, 42);
+  });
+}).call(this);
+
 // Generated by LiveScript 1.3.1
 (function(){
   var isFunction, isIterator, same, getOwnPropertyDescriptor, freeze, eq, deq, toString$ = {}.toString;
diff --git a/tests/tests/es6.regexp.replace.ls b/tests/tests/es6.regexp.replace.ls
new file mode 100644
index 000000000000..347d8ffdc36e
--- /dev/null
+++ b/tests/tests/es6.regexp.replace.ls
@@ -0,0 +1,86 @@
+QUnit.module \ES6
+
+eq = strictEqual
+
+test 'String#replace regression' !->
+  ok typeof! ''replace is \Function, 'String#replace is function'
+  eq ''replace.length, 2, 'String#replace length is 2'
+  ok /native code/.test(''replace), 'looks like native'
+  if \name of ''replace => eq ''replace.name, \replace, 'String#replace is "replace" (can fail if compressed)'
+  # based on https://github.com/tc39/test262/tree/master/test/built-ins/String/prototype/replace
+  instance = Object true
+  instance.replace = String::replace
+  eq instance.replace(on, 1), \1, 'S15.5.4.11_A1_T1'
+  instance = Object no
+  instance.replace = String::replace
+  eq instance.replace(no, void), \undefined, 'S15.5.4.11_A1_T2'
+  eq 'gnulluna'replace(null, (a1, a2, a3)-> a2 + ''), \g1una, 'S15.5.4.11_A1_T4'
+  eq 'gnulluna'replace(null, ->), \gundefineduna, 'S15.5.4.11_A1_T5'
+  eq Object(\undefined)replace(void, -> &[1] + 42), \42, 'S15.5.4.11_A1_T6'
+  eq 'undefined'replace(\e, void), \undundefinedfined, 'S15.5.4.11_A1_T7'
+  eq String({toString: ->})replace(/e/g, void), \undundefinedfinundefinedd, 'S15.5.4.11_A1_T8'
+  eq new String({valueOf: (->), toString: void})replace((->)!, (a1, a2, a3)-> a1 + a2 + a3), \undefined0undefined, 'S15.5.4.11_A1_T9'
+  eq 'ABB\u0041BABAB'replace({toString: -> '\u0041B'}, ->), \undefinedBABABAB, 'S15.5.4.11_A1_T10'
+  try
+    'ABB\u0041BABAB'replace {toString: -> throw \insearchValue}, {toString: -> throw \inreplaceValue}
+    ok no, 'S15.5.4.11_A1_T11 #1 lead to throwing exception'
+  catch e
+    eq e, \insearchValue, 'S15.5.4.11_A1_T11 #2'
+  try
+    Object('ABB\u0041BABAB')replace {toString: (->{}), valueOf: -> throw \insearchValue}, {toString: -> throw \inreplaceValue}
+    ok no, 'S15.5.4.11_A1_T12 #1 lead to throwing exception'
+  catch e
+    eq e, \insearchValue, 'S15.5.4.11_A1_T12 #2'
+  try
+    'ABB\u0041BABAB\u0031BBAA'replace {toString: (->{}), valueOf: -> throw \insearchValue}, {toString: -> 1}
+    ok no, 'S15.5.4.11_A1_T13 #1 lead to throwing exception'
+  catch e
+    eq e, \insearchValue, 'S15.5.4.11_A1_T13 #2'
+  eq 'ABB\u0041BABAB\u0037\u0037BBAA'replace(new RegExp(\77), 1), 'ABBABABAB\u0031BBAA', 'S15.5.4.11_A1_T14'
+  instance = Object 1100.00777001
+  instance.replace = String::replace
+  try
+    instance.replace {toString: -> /77/}, 1
+    ok no, 'S15.5.4.11_A1_T15 #1 lead to throwing exception'
+  catch e
+    ok e instanceof TypeError, 'S15.5.4.11_A1_T15 #2'
+  instance = Object 1100.00777001
+  instance.replace = String::replace
+  try
+    instance.replace /77/, {toString: -> (a1, a2, a3)-> a2 + \z}
+    ok no, 'S15.5.4.11_A1_T16 #1 lead to throwing exception'
+  catch e
+    ok e instanceof TypeError, 'S15.5.4.11_A1_T16 #2'
+  eq 'asdf'replace(RegExp('' \g), \1), \1a1s1d1f1, 'S15.5.4.11_A1_T17'
+  eq 'She sells seashells by the seashore.'replace(/sh/g, \sch), 'She sells seaschells by the seaschore.', 'S15.5.4.11_A2_T1'
+  eq 'She sells seashells by the seashore.'replace(/sh/g, \$$sch), 'She sells sea$schells by the sea$schore.', 'S15.5.4.11_A2_T2'
+  eq 'She sells seashells by the seashore.'replace(/sh/g, '$&sch'), 'She sells seashschells by the seashschore.', 'S15.5.4.11_A2_T3'
+  eq 'She sells seashells by the seashore.'replace(/sh/g, '$`sch'), 'She sells seaShe sells seaschells by the seaShe sells seashells by the seaschore.', 'S15.5.4.11_A2_T4'
+  eq 'She sells seashells by the seashore.'replace(/sh/g, "$'sch"), 'She sells seaells by the seashore.schells by the seaore.schore.', 'S15.5.4.11_A2_T5'
+  eq 'She sells seashells by the seashore.'replace(/sh/, \sch), 'She sells seaschells by the seashore.', 'S15.5.4.11_A2_T6'
+  eq 'She sells seashells by the seashore.'replace(/sh/, \$$sch), 'She sells sea$schells by the seashore.', 'S15.5.4.11_A2_T7'
+  eq 'She sells seashells by the seashore.'replace(/sh/, '$&sch'), 'She sells seashschells by the seashore.', 'S15.5.4.11_A2_T8'
+  eq 'She sells seashells by the seashore.'replace(/sh/, '$`sch'), 'She sells seaShe sells seaschells by the seashore.', 'S15.5.4.11_A2_T9'
+  eq 'She sells seashells by the seashore.'replace(/sh/, "$'sch"), 'She sells seaells by the seashore.schells by the seashore.', 'S15.5.4.11_A2_T10'
+  eq 'uid=31'replace(/(uid=)(\d+)/, '$1115'), 'uid=115', 'S15.5.4.11_A3_T1'
+  eq 'uid=31'replace(/(uid=)(\d+)/, '$11A15'), 'uid=1A15', 'S15.5.4.11_A3_T3'
+  eq 'abc12 def34'replace(/([a-z]+)([0-9]+)/, -> &.2 + &.1), '12abc def34', 'S15.5.4.11_A4_T1'
+  eq 'aaaaaaaaaa,aaaaaaaaaaaaaaa'replace(/^(a+)\1*,\1+$/, '$1'), \aaaaa, 'S15.5.4.11_A5_T1'
+
+test 'RegExp#@@replace' !->
+  ok typeof! /./[Symbol.replace] is \Function, 'RegExp#@@replace is function'
+  eq /./[Symbol.replace].length, 2, 'RegExp#@@replace length is 2'
+  eq /([a-z]+)([0-9]+)/[Symbol.replace]('abc12 def34', -> &.2 + &.1), '12abc def34'
+
+test '@@replace logic' !->
+  O = {(Symbol.replace): (a, b)-> {a, b}}
+  eq 'qwe'replace(O, 42)a, \qwe
+  eq 'qwe'replace(O, 42)b, 42
+  eq ''replace.call(123, O, 42)a, \123
+  eq ''replace.call(123, O, 42)b, 42
+  re = /./
+  re[Symbol.replace] = (a, b)-> {a, b}
+  eq 'qwe'replace(re, 42)a, \qwe
+  eq 'qwe'replace(re, 42)b, 42
+  eq ''replace.call(123, re, 42)a, \123
+  eq ''replace.call(123, re, 42)b, 42
\ No newline at end of file