283477 - String.prototype.lastIndexOf returns numbers smaller than -1 on failure

Status: VERIFIED FIXED

(Core :: JavaScript Engine, defect, P1)

Description

[Sjoerd Visscher]

a.lastIndexOf(b, c) should return -1 when there is no match, but it returns
a.length - b.length when a is shorter than b and c is, or can be converted to, a
number.

Example: 
"".lastIndexOf("hello", 0) returns -5
"".lastIndexOf("hello") returns -1

Comment 1

[Brendan Eich [:brendan]]

Thanks, this bug is almost ten years old!  Fix forthwith.

/be

Comment 2

[Brendan Eich [:brendan]]

Attachment: fix

Conserving the original code structure, but if you follow ECMA-262 Edition 3,
the code would be

	    d = js_DoubleToInteger(d);
	    i = (jsint) JS_MIN(JS_MAX(d, 0), textlen);

Checking in now.

/be

Comment 3

[Brendan Eich [:brendan]]

Sjoerd, thanks very much!

Surprising that the testsuite didn't insist on -1 for patlen > textlen, but
there it is: a hole in test coverage.  Not the last one, either!

/be

Comment 4

[Sjoerd Visscher]

Well, if you write code for Mozilla, the whole world is your testsuite. 
My "Find previous" code always found matches on empty lines!

But thanks for the quick response. Maybe if you have time you could add a
comment (just a comment, not a fix) to bug 274888 too.

Comment 5

[Bob Clary [:bc] (inactive)]

js/tests/js1_5/Regress/regress-283477.js checked in.

Comment 6

[Bob Clary [:bc] (inactive)]

verified fixed 1.8.x and trunk.