612580 - Javascript implementation of substring causes unexpected behavior when end index is undefined.

Status: RESOLVED DUPLICATE of bug 373118

(Core :: JavaScript Engine, defect)

Description

[Ryan]

User-Agent:       Opera/9.80 (Windows NT 6.1; U; en) Presto/2.6.30 Version/10.63
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.1.15) Gecko/20101026 Firefox/3.5.15

If the end index is undefined when calling substring on a string in certain conditions the call will return nothing rather than start index to the end of the string.

Reproducible: Always

Steps to Reproduce:
var testString = "This is a test.";
var startIndex = 0;
var endIndex;
testString.substring(startIndex, endIndex);
Actual Results:  
""

Expected Results:  
"This is a test."

Comment 1

[Boris Zbarsky [:bzbarsky]]

Ryan, thanks for the bug report!  This will be fixed in Gecko 2.0; you can test out the fix in Firefox 4 beta 7 if you want.