Bug 3144 - Incorrect regex matching with empty pattern at the beginning of group
Summary: Incorrect regex matching with empty pattern at the beginning of group
Alias: None
Product: Class Libraries
Classification: Mono
Component: mscorlib ()
Version: 2.10.x
Hardware: PC Linux
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2012-01-30 14:37 UTC by gsvick
Modified: 2014-11-25 05:03 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description gsvick 2012-01-30 14:37:22 UTC
Description of Problem:

The regular expression "^(|.*)*$" should match any string, but it doesn't. On the other hand, both "^(|.*)$" (without asterisk) and "^(.*|)*$" (with the empty pattern moved) seem to work correctly.

Steps to reproduce the problem:

Compile and run a program with the following code in Main():

string text = "text";
var regex = new Regex("^(|.*)*$");
var match = regex.Match(text);

Actual Results:

The value of match.Success is false.

Expected Results:

The value of match.Success is true and match should contain the whole matched string.

How often does this happen? 


Additional Information:

Compiled using Monodevelop 2.6 and run under mono 2.10.5.
Comment 1 Marek Safar 2014-11-25 05:03:37 UTC
Resolved in master