Update V8 to r5780 as required by WebKit r71558

Change-Id: Ie3936550b99967a13755930d0dac0a59c3562625
diff --git a/test/mjsunit/debug-compile-event.js b/test/mjsunit/debug-compile-event.js
index e7ecf47..b00a907 100644
--- a/test/mjsunit/debug-compile-event.js
+++ b/test/mjsunit/debug-compile-event.js
@@ -36,7 +36,6 @@
 var source_count = 0;  // Total number of scources compiled.
 var host_compilations = 0;  // Number of scources compiled through the API.
 var eval_compilations = 0;  // Number of scources compiled through eval.
-var json_compilations = 0;  // Number of scources compiled through JSON.parse.
 
 
 function compileSource(source) {
@@ -62,9 +61,6 @@
           case Debug.ScriptCompilationType.Eval:
             eval_compilations++;
             break;
-          case Debug.ScriptCompilationType.JSON:
-            json_compilations++;
-            break;
         }
       }
 
@@ -74,13 +70,6 @@
         // For source with 'eval' there will be compile events with substrings
         // as well as with with the exact source.
         assertTrue(current_source.indexOf(event_data.script().source()) >= 0);
-      } else if (current_source.indexOf('JSON.parse') == 0) {
-        // For JSON the JSON source will be in parentheses.
-        var s = event_data.script().source();
-        if (s[0] == '(') {
-          s = s.substring(1, s.length - 2);
-        }
-        assertTrue(current_source.indexOf(s) >= 0);
       } else {
         // For source without 'eval' there will be a compile events with the
         // exact source.
@@ -113,7 +102,7 @@
 compileSource('eval("eval(\'(function(){return a;})\')")');
 source_count += 2;  // Using eval causes additional compilation event.
 compileSource('JSON.parse(\'{"a":1,"b":2}\')');
-source_count++;  // Using JSON.parse causes additional compilation event.
+// Using JSON.parse does not causes additional compilation events.
 compileSource('x=1; //@ sourceURL=myscript.js');
 
 // Make sure that the debug event listener was invoked.
@@ -123,10 +112,9 @@
 assertEquals(before_compile_count, after_compile_count);
 
 // Check the actual number of events (no compilation through the API as all
-// source compiled through eval except for one JSON.parse call).
+// source compiled through eval).
 assertEquals(source_count, after_compile_count);
 assertEquals(0, host_compilations);
-assertEquals(source_count - 1, eval_compilations);
-assertEquals(1, json_compilations);
+assertEquals(source_count, eval_compilations);
 
 Debug.setListener(null);
diff --git a/test/mjsunit/mirror-script.js b/test/mjsunit/mirror-script.js
index 8631028..7156170 100644
--- a/test/mjsunit/mirror-script.js
+++ b/test/mjsunit/mirror-script.js
@@ -83,12 +83,10 @@
 
 
 // Test the script mirror for different functions.
-testScriptMirror(function(){}, 'mirror-script.js', 100, 2, 0);
+testScriptMirror(function(){}, 'mirror-script.js', 98, 2, 0);
 testScriptMirror(Math.sin, 'native math.js', -1, 0, 0);
 testScriptMirror(eval('(function(){})'), null, 1, 2, 1, '(function(){})', 87);
 testScriptMirror(eval('(function(){\n  })'), null, 2, 2, 1, '(function(){\n  })', 88);
-testScriptMirror(%CompileString('{"a":1,"b":2}', true), null, 1, 2, 2, '{"a":1,"b":2}');
-testScriptMirror(%CompileString('{"a":1,\n  "b":2}', true), null, 2, 2, 2, '{"a":1,\n  "b":2}');
 
 // Test taking slices of source.
 var mirror = debug.MakeMirror(eval('(function(){\n  1;\n})')).script();
diff --git a/test/mjsunit/mjsunit.status b/test/mjsunit/mjsunit.status
index 3c8cbdb..820dca7 100644
--- a/test/mjsunit/mjsunit.status
+++ b/test/mjsunit/mjsunit.status
@@ -45,6 +45,10 @@
 # Skip long running test in debug and allow it to timeout in release mode.
 regress/regress-524: (PASS || TIMEOUT), SKIP if $mode == debug
 
+# Stack manipulations in LiveEdit are buggy - see bug 915
+debug-liveedit-check-stack: SKIP
+debug-liveedit-patch-positions-replace: SKIP
+
 [ $arch == arm ]
 
 # Slow tests which times out in debug mode.
@@ -61,14 +65,9 @@
 # Skip long running test in debug mode on ARM.
 string-indexof-2: PASS, SKIP if $mode == debug
 
-# Stack manipulations in LiveEdit is implemented for ia32 only.
-debug-liveedit-check-stack: SKIP
 
 [ $arch == mips ]
 
-# Stack manipulations in LiveEdit is implemented for ia32 only.
-debug-liveedit-check-stack: SKIP
-
 # Skip all tests on MIPS.
 *: SKIP
 
diff --git a/test/mjsunit/object-literal-conversions.js b/test/mjsunit/object-literal-conversions.js
new file mode 100644
index 0000000..8540d93
--- /dev/null
+++ b/test/mjsunit/object-literal-conversions.js
@@ -0,0 +1,46 @@
+// Copyright 2010 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Test that the various conversions between property names are correctly
+// used when overwriting initializers.
+
+var test1 = { 13: 6, "13": 7 };
+var test2 = { 13: 7, "13.0": 6 };
+var test3 = { "13": 6, 13.0000000000000000: 7 };
+var test4 = { 13.213000: 6, "13.213": 7 };
+
+assertEquals(7, test1[13]);
+assertEquals(7, test2[13]);
+assertEquals(7, test3[13]);
+assertEquals(7, test4[13.213]);
+
+var test5 = { 13: function() {}, "13": 7 };
+var test6 = { 17.31: function() {}, "17.31": 7 };
+
+assertEquals(7, test5[13]);
+assertEquals(7, test6[17.31]);
+  
\ No newline at end of file
diff --git a/test/mjsunit/object-literal-overwrite.js b/test/mjsunit/object-literal-overwrite.js
new file mode 100644
index 0000000..5c58a2d
--- /dev/null
+++ b/test/mjsunit/object-literal-overwrite.js
@@ -0,0 +1,118 @@
+// Copyright 2010 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Check that constants and computed properties are overwriting each other
+// correctly, i.e., the last initializer for any name is stored in the object.
+
+
+// Tests for the full code generator (if active).
+
+var foo1 = {
+  bar: 6,
+  bar: 7
+};
+
+var foo2 = {
+  bar: function(a){},
+  bar: 7
+};
+
+var foo3 = {
+  bar: function(a){},
+  bar: function(b){},
+  bar: 7
+};
+
+var foo4 = {
+  bar: function(b){},
+  bar: 7,
+  bar: function(){return 7},
+};
+
+var foo5 = {
+  13: function(a){},
+  13: 7
+}
+
+var foo6 = {
+  14.31: function(a){},
+  14.31: 7
+}
+
+var foo7 = {
+  15: 6,
+  15: 7
+}
+
+assertEquals(7, foo1.bar);
+assertEquals(7, foo2.bar);
+assertEquals(7, foo3.bar);
+assertEquals(7, foo4.bar());
+assertEquals(7, foo5[13]);
+assertEquals(7, foo6[14.31]);
+assertEquals(7, foo7[15]);
+
+// Test for the classic code generator.
+
+function fun(x) {
+  var inner = { j: function(x) { return x; }, j: 7 }; 
+  return inner.j;
+}
+
+assertEquals(7, fun(7) );
+
+// Check that the initializers of computed properties are executed, even if
+// no store instructions are generated for the literals.
+
+var glob1 = 0;
+
+var bar1 = { x: glob1++, x: glob1++, x: glob1++, x: 7};
+
+assertEquals(3, glob1);
+
+
+var glob2 = 0;
+
+function fun2() {
+  var r = { y: glob2++, y: glob2++, y: glob2++, y: 7};
+  return r.y;
+}
+
+var y = fun2();
+assertEquals(7, y);
+assertEquals(3, glob2);
+
+var glob3 = 0;
+
+function fun3() {
+  var r = { 113: glob3++, 113: glob3++, 113: glob3++, 113: 7};
+  return r[113];
+}
+
+var y = fun3();
+assertEquals(7, y);
+assertEquals(3, glob3);
\ No newline at end of file
diff --git a/test/mjsunit/regress/regress-conditional-position.js b/test/mjsunit/regress/regress-conditional-position.js
new file mode 100644
index 0000000..cd8f7bd
--- /dev/null
+++ b/test/mjsunit/regress/regress-conditional-position.js
@@ -0,0 +1,95 @@
+// Copyright 2010 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --always-full-compiler
+
+var functionToCatch;
+var lineNumber;
+
+function catchLineNumber () {
+  var x = {};
+
+  Error.prepareStackTrace = function (error, stackTrace) {
+    stackTrace.some(function (frame) {
+      if (frame.getFunction() == functionToCatch) {
+        lineNumber = frame.getLineNumber();
+        return true;
+      }
+      return false;
+    });
+    return lineNumber;
+  };
+
+  Error.captureStackTrace(x);
+  return x.stack;
+}
+
+function log() {
+  catchLineNumber();
+}
+
+function foo() {}
+
+function test1() {
+  log(foo() == foo()
+      ? 'a'
+      : 'b');
+}
+
+function test2() {
+  var o = { foo: function () {}}
+  log(o.foo() == o.foo()
+      ? 'a'
+      : 'b');
+}
+
+function test3() {
+  var o = { log: log, foo: function() { } };
+  o.log(o.foo() == o.foo()
+      ? 'a'
+      : 'b');
+
+}
+
+function test(f, expectedLineNumber) {
+  functionToCatch = f;
+  f();
+
+  assertEquals(expectedLineNumber, lineNumber);
+}
+
+test(test1, 58);
+test(test2, 65);
+test(test3, 72);
+
+eval(test1.toString() + "//@ sourceUrl=foo");
+eval(test2.toString() + "//@ sourceUrl=foo");
+eval(test3.toString() + "//@ sourceUrl=foo");
+
+test(test1, 2);
+test(test2, 3);
+test(test3, 3);
diff --git a/test/mjsunit/string-externalize.js b/test/mjsunit/string-externalize.js
index 5b1f917..da89786 100644
--- a/test/mjsunit/string-externalize.js
+++ b/test/mjsunit/string-externalize.js
@@ -25,7 +25,7 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --expose-externalize-string
+// Flags: --expose-externalize-string --expose-gc
 
 var size = 1024;
 
@@ -93,3 +93,7 @@
 for (var i = 0; i < 10; i++) {
   test();
 }
+
+// Clean up string to make Valgrind happy.
+gc();
+gc();
diff --git a/test/mjsunit/string-replace-with-empty.js b/test/mjsunit/string-replace-with-empty.js
index 0e1e70a..aa97f27 100644
--- a/test/mjsunit/string-replace-with-empty.js
+++ b/test/mjsunit/string-replace-with-empty.js
@@ -25,33 +25,45 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --expose-externalize-string
+// Flags: --expose-externalize-string --expose-gc
 
-assertEquals("0123", "aa0bb1cc2dd3".replace(/[a-z]/g, ""));
-assertEquals("0123", "\u1234a0bb1cc2dd3".replace(/[\u1234a-z]/g, ""));
+function test() {
+  assertEquals("0123", "aa0bb1cc2dd3".replace(/[a-z]/g, ""));
+  assertEquals("0123", "\u1234a0bb1cc2dd3".replace(/[\u1234a-z]/g, ""));
 
-var expected = "0123";
-var cons = "a0b1c2d3";
-for (var i = 0; i < 5; i++) {
-  expected += expected;
-  cons += cons;
-}
-assertEquals(expected, cons.replace(/[a-z]/g, ""));
-cons = "\u12340b1c2d3";
-for (var i = 0; i < 5; i++) {
-  cons += cons;
-}
-assertEquals(expected, cons.replace(/[\u1234a-z]/g, ""));
+  var expected = "0123";
+  var cons = "a0b1c2d3";
+  for (var i = 0; i < 5; i++) {
+    expected += expected;
+    cons += cons;
+  }
+  assertEquals(expected, cons.replace(/[a-z]/g, ""));
+  cons = "\u12340b1c2d3";
+  for (var i = 0; i < 5; i++) {
+    cons += cons;
+  }
+  assertEquals(expected, cons.replace(/[\u1234a-z]/g, ""));
 
-cons = "a0b1c2d3";
-for (var i = 0; i < 5; i++) {
-  cons += cons;
+  cons = "a0b1c2d3";
+  for (var i = 0; i < 5; i++) {
+    cons += cons;
+  }
+  externalizeString(cons, true/* force two-byte */);
+  assertEquals(expected, cons.replace(/[a-z]/g, ""));
+  cons = "\u12340b1c2d3";
+  for (var i = 0; i < 5; i++) {
+    cons += cons;
+  }
+  externalizeString(cons);
+  assertEquals(expected, cons.replace(/[\u1234a-z]/g, ""));
 }
-externalizeString(cons, true/* force two-byte */);
-assertEquals(expected, cons.replace(/[a-z]/g, ""));
-cons = "\u12340b1c2d3";
-for (var i = 0; i < 5; i++) {
-  cons += cons;
-}
-externalizeString(cons);
-assertEquals(expected, cons.replace(/[\u1234a-z]/g, ""));
+
+test();
+
+// Clear the regexp cache to allow the GC to work.
+"foo".replace(/foo/g, "");
+
+// GC in order to free up things on the C side so we don't get
+// a memory leak.  This makes valgrind happy.
+gc();
+gc();
diff --git a/test/mjsunit/string-split.js b/test/mjsunit/string-split.js
index 59d3ad3..c741f6a 100644
--- a/test/mjsunit/string-split.js
+++ b/test/mjsunit/string-split.js
@@ -27,76 +27,45 @@
 
 expected = ["A", undefined, "B", "bold", "/", "B", "and", undefined, "CODE", "coded", "/", "CODE", ""];
 result = "A<B>bold</B>and<CODE>coded</CODE>".split(/<(\/)?([^<>]+)>/);
-assertArrayEquals(expected, result, 1);
+assertArrayEquals(expected, result);
 
-expected = ["a", "b"];
-result = "ab".split(/a*?/);
-assertArrayEquals(expected, result, 2);
 
-expected = ["", "b"];
-result = "ab".split(/a*/);
-assertArrayEquals(expected, result, 3);
+assertArrayEquals(["a", "b"], "ab".split(/a*?/));
 
-expected = ["a"];
-result = "ab".split(/a*?/, 1);
-assertArrayEquals(expected, result, 4);
+assertArrayEquals(["", "b"], "ab".split(/a*/));
 
-expected = [""];
-result = "ab".split(/a*/, 1);
-assertArrayEquals(expected, result, 5);
+assertArrayEquals(["a"], "ab".split(/a*?/, 1));
 
-expected = ["as","fas","fas","f"];
-result = "asdfasdfasdf".split("d");
-assertArrayEquals(expected, result, 6);
+assertArrayEquals([""], "ab".split(/a*/, 1));
 
-expected = ["as","fas","fas","f"];
-result = "asdfasdfasdf".split("d", -1);
-assertArrayEquals(expected, result, 7);
+assertArrayEquals(["as","fas","fas","f"], "asdfasdfasdf".split("d"));
 
-expected = ["as", "fas"];
-result = "asdfasdfasdf".split("d", 2);
-assertArrayEquals(expected, result, 8);
+assertArrayEquals(["as","fas","fas","f"], "asdfasdfasdf".split("d", -1));
 
-expected = [];
-result = "asdfasdfasdf".split("d", 0);
-assertArrayEquals(expected, result, 9);
+assertArrayEquals(["as", "fas"], "asdfasdfasdf".split("d", 2));
 
-expected = ["as","fas","fas",""];
-result = "asdfasdfasd".split("d");
-assertArrayEquals(expected, result, 10);
+assertArrayEquals([], "asdfasdfasdf".split("d", 0));
 
-expected = [];
-result = "".split("");
-assertArrayEquals(expected, result, 11);
+assertArrayEquals(["as","fas","fas",""], "asdfasdfasd".split("d"));
 
-expected = [""]
-result = "".split("a");
-assertArrayEquals(expected, result, 12);
+assertArrayEquals([], "".split(""));
 
-expected = ["a","b"]
-result = "axxb".split(/x*/);
-assertArrayEquals(expected, result, 13);
+assertArrayEquals([""], "".split("a"));
 
-expected = ["a","b"]
-result = "axxb".split(/x+/);
-assertArrayEquals(expected, result, 14);
+assertArrayEquals(["a","b"], "axxb".split(/x*/));
 
-expected = ["a","","b"]
-result = "axxb".split(/x/);
-assertArrayEquals(expected, result, 15);
+assertArrayEquals(["a","b"], "axxb".split(/x+/));
+
+assertArrayEquals(["a","","b"], "axxb".split(/x/));
 
 // This was http://b/issue?id=1151354
-expected = ["div", "#id", ".class"]
-result = "div#id.class".split(/(?=[#.])/);
-assertArrayEquals(expected, result, 16);
+assertArrayEquals(["div", "#id", ".class"], "div#id.class".split(/(?=[#.])/));
 
-expected = ["div", "#i", "d", ".class"]
-result = "div#id.class".split(/(?=[d#.])/);
-assertArrayEquals(expected, result, 17);
 
-expected = ["a", "b", "c"]
-result = "abc".split(/(?=.)/);
-assertArrayEquals(expected, result, 18);
+assertArrayEquals(["div", "#i", "d", ".class"], "div#id.class".split(/(?=[d#.])/));
+
+assertArrayEquals(["a", "b", "c"], "abc".split(/(?=.)/));
+
 
 /* "ab".split(/((?=.))/)
  * 
@@ -108,19 +77,23 @@
  * 
  * Opera seems to have this right.  The others make no sense.
  */
-expected = ["a", "", "b"]
-result = "ab".split(/((?=.))/);
-assertArrayEquals(expected, result, 19);
+assertArrayEquals(["a", "", "b"], "ab".split(/((?=.))/));
 
 /* "ab".split(/(?=)/)
  *
  * KJS:   a,b
  * SM:    ab
  * IE:    a,b
- * Opera: a,b
+ * Opera: a,bb
  * V8:    a,b
  */
-expected = ["a", "b"]
-result = "ab".split(/(?=)/);
-assertArrayEquals(expected, result, 20);
+assertArrayEquals(["a", "b"], "ab".split(/(?=)/));
 
+
+// For issue http://code.google.com/p/v8/issues/detail?id=924
+// Splitting the empty string is a special case.
+assertEquals([""], ''.split());
+assertEquals([""], ''.split(/./));
+assertEquals([], ''.split(/.?/));
+assertEquals([], ''.split(/.??/));
+assertEquals([], ''.split(/()()/));