46429 - Regexp matching error in JS Engine

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect, P3)

Description

[Patrick]

From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux 2.2.13 i686; en-US; m17) Gecko/20000724
BuildID:    2000072420

The match property of a String object in javascript produces an erroneus match
inside a bookmarklet

Reproducible: Always
Steps to Reproduce:
1. create a new bookmarklet by pasting the javascript code below into a new bookmark
2. click on the bookmark, executing the bookmarklet (you must have javascript
turned on for this)
3. the code produces an alert box illustrating the way the string was matched
against the regexp


Actual Results:  the alert box says:
~aa123bb -> [123bb] [123bb] [123] [bb]

Expected Results:  it should say (and does so in Netscape 4.x ):
~aa123bb -> [~aa123bb] [~aa] [123] [bb]

Testcase: (jacascript code from a bookmarklet)
----
javascript:string="~aa123bb"; regexp=/(.*[a-z])?(\d+)(\w*)/;
result = string.match(regexp);
alert(string+ " -> ["+result[0]+"] ["+result[1]+"] ["+result[2]+"]
["+result[3]+"]");
------
The regexp is supposed to break up the string into a an optional part ending
with a letter, then a number and then more letters. Note: It seems to work for
just matching the first 2 parts of the regexp against "~aa123"

Comment 1

[Gregory McLean]

I can confirm this with 2000080113 on Linux.
Addtionally the console spits the following out:
Error loading URL javascript:string="~aa123bb"; regexp=/(.*[a-z])?(\d+)(\w*)/;
result = string.match(regexp); alert(string+ " -> ["+result[0]+"]
["+result[1]+"] ["+result[2]+"] ["+result[3]+"]");

Comment 2

[rogerl (gone)]

This is an example of failures in the general case of ([a-z]*[a-z])*b (i.e. the 
outer back-tracker is not informed of success by the inner back-tracker). Urgh.

Comment 3

[Phil Schwartau]

Updating summary -

Comment 4

[Patrick C. Beard]

This a serious regression. Marking nsbeta3+.

Comment 5

[Patrick]

*** Bug 48568 has been marked as a duplicate of this bug. ***

Comment 6

[rogerl (gone)]

*** Bug 48568 has been marked as a duplicate of this bug. ***

Comment 7

[rogerl (gone)]

Fix checked in