Fix some bugs in accessing details of the lastest regexp

test/mjsunit/regexp-capture-3.js

Index: test/mjsunit/regexp-capture-3.js
===================================================================
--- test/mjsunit/regexp-capture-3.js	(revision 11415)
+++ test/mjsunit/regexp-capture-3.js	(working copy)
@@ -86,3 +86,71 @@
 for (var i = 3; i < 10; i++) {
   assertEquals("", RegExp['$' + i]);
 }
+
+
+function Override() {
+  // Set the internal lastMatchInfoOverride.  After calling this we do a normal
+  // match and verify the override was cleared and that we record the new
+  // captures.
+  "abcdabcd".replace(/(b)(c)/g, function() { });
+}
+
+
+function TestOverride(input, expect, property, re_src) {
+  var re = new RegExp(re_src);
+  var re_g = new RegExp(re_src, "g");
+
+  function OverrideCase(fn) {
+    Override();
+    fn();
+    assertEquals(expect, RegExp[property]);
+  }
+
+  OverrideCase(function() { return input.replace(re, "x"); });
+  OverrideCase(function() { return input.replace(re_g, "x"); });
+  OverrideCase(function() { return input.replace(re, ""); });
+  OverrideCase(function() { return input.replace(re_g, ""); });
+  OverrideCase(function() { return input.match(re); });
+  OverrideCase(function() { return input.match(re_g); });
+  OverrideCase(function() { return re.test(input); });
+  OverrideCase(function() { return re_g.test(input); });
+}
+
+var input = "bar.foo baz......";
+var re_str = "(ba.).*?f";
+TestOverride(input, "bar", "$1", re_str);
+
+input = "foo bar baz";
+var re_str = "bar";
+TestOverride(input, "bar", "$&", re_str);
+
+
+function no_last_match(fn) {
+  fn();
+  assertEquals("hestfisk", RegExp.$1);
+}
+
+/(hestfisk)/.test("There's no such thing as a hestfisk!");
+
+no_last_match(function() { "foo".replace("f", ""); });
+no_last_match(function() { "foo".replace("f", "f"); });
+no_last_match(function() { "foo".split("o"); });
+
+var base = "In the music.  In the music.  ";
+var cons = base + base + base + base;
+no_last_match(function() { cons.replace("x", "y"); });
+no_last_match(function() { cons.replace("e", "E"); });
+
+
+// Here's one that matches once, then tries to match again, but fails.
+// Verify that the last match info is from the last match, not from the
+// failure that came after.
+"bar.foo baz......".replace(/(ba.).*?f/g, function() { return "x";});
+assertEquals("bar", RegExp.$1);
+
+
+var a = "foo bar baz".replace(/^|bar/g, "");
+assertEquals("foo  baz", a);
+
+a = "foo bar baz".replace(/^|bar/g, "*");
+assertEquals("*foo * baz", a);