265762 - Javascript "invalid quantifier" message received when calling replace function

Status: RESOLVED WONTFIX

(Core :: JavaScript Engine, defect)

Description

[Sohail Mirza]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; rv:1.7.3) Gecko/20040913 Firefox/0.10.1
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; rv:1.7.3) Gecko/20040913 Firefox/0.10.1

I encountered this problem when looking into a defect report filed by a client
that was having a problem in their migration to Netscape 7 (not sure which
specific version).

When a script tag has specified the language in type ONLY by using the now
deprecated "language" attribute, a strange javascript error is encountered when
attempting to replace the '+' or '*' characters.

The replace function call is being made as such:

var temp = str.replace("+", " ");

Using that call will result in the following Javascript error:

Error: invalid quantifier *

There are three workarounds that I discovered:

1)  Specify the language as "JavaScript" instead of a more specific version such
as "JavaScript1.2".
2)  Use the more acceptable "type" attribute.  When specifying the type as
"text/javascript" the script will run without error whether the language is
specified or not.
3)  Alternately, search for the '+' or '*' characters via regex, like so:

var temp = str.replace(/\+/, " ");

This problem was always reproducible on any Gecko embedding browser (Mozilla
Suite, Netscape, Firefox) produced from a version of the Mozilla codebase, later
than version 1.4.  Where Netscape 7.1 would running the problem script without
error, Netscape 7.2 would not.

The following is a list of user-agents I tried and was successfully able to
reproduce the problem with:

Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.2) Gecko/20040804
Netscape/7.2 (ax)
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.6) Gecko/20040113
Mozilla/5.0 (Windows; U; Windows NT 5.1; rv:1.7.3) Gecko/20040913 Firefox/0.10.1

I did try Netscape 7.1 (based on Mozilla 1.4) and could run the problem script
successfully.  I did not record the exact user-agent string, unfortunately.

I will attach 4 test cases -- 1 illustrating the problem, and 3 implementing the
various workarounds.

Reproducible: Always
Steps to Reproduce:
1. Write script tag specifying a language of "JavaScript1.2"
2. Utilize 'replace' function to replace instances of the '+' or '*' characters
in a string with any other character(s)
3. Run script.

Actual Results:  
Recorded javascript error, " Error: invalid quantifier * ".

Expected Results:  
Run through script successfully.

Comment 1

[Sohail Mirza]

Attachment: Testcase with error.

Comment 2

[Sohail Mirza]

Attachment: First testcase that works.

This testcase implements the script "type" workaround.

Comment 3

[Sohail Mirza]

Attachment: Second testcase that works.

This testcase implements the language="JavaScript" workaround.

Comment 4

[Sohail Mirza]

Attachment: Third testcase that works.

This testcase implements the regex workaround.

Comment 5

[Brendan Eich [:brendan]]

Deprecation (hardly effective in the real world) of language has nothing to do
with the problem you see -- if you had used <script
type="application/x-javascript;version=1.2"> you would have seen the same results.

Why are you selecting 1.2?  It's an ancient version, not compatible with
ECMA-262 because it actually pre-dates the final Edition 1 spec, and our
compatibility code was carried along from the days when Netscape had enough
market share to matter.  It seems IE and Opera do not make changes to JS syntax
or semantics based on any version selector, so we're considering doing likewise
for HTML scripts.

More when I have time to analyze this in a fresh build.

/be

Comment 6

[Sohail Mirza]

Just a clarification:  it is not my choice to use version 1.2.

I work for a Fortune 500 company and our team supports a legacy application
served to hundreds of thousands of users.  To change all our script tags would
require a monumental effort and a fairly large investment.  One of our clients
recently updated their workstations to use some version of the Mozilla suite
(obviously later than 1.4), and our app broke.

I implemented a workaround, but just filed the bug to in case the issue is due
to a regression in the Moz JS Engine functionality.  :)

Comment 7

[Bob Clary [:bc] (inactive)]

Sohail, just for curiosity's sake, how are the files of your application stored?
are they simply text files or are they embedded in a database? If they are in
text files, a simple command line program can change strings of the form
language="javascript1.2" to language="javascript" in an arbitrary number of
files. The only outstanding issue would be caching of the files in your client's
browsers.

Comment 8

[Sohail Mirza]

bc, while I'd love to do that, the beaurocracy and overhead involved in doing
that (not to mention the expense of regression testing every script in the
application) would make it more plausible for our organization to fund a
re-write of the entire Mozilla line of applications!  :)

Again, it's not in my control to do that.  :)

Comment 9

[Bob Clary [:bc] (inactive)]

background info (see the implementation note)
http://bclary.com/2004/09/26/boot-camp-javascript#String.prototype.replace

this behavior will change in firefox 1.1 and mozilla 1.8 due to bug 255895. 

considering this behavior is by design, marking invalid.

Comment 10

[Sohail Mirza]

Bob,

Thank you for your response, and for taking the time to reply to the bug.  :)

Your efforts are much appreciated!

Sohail Mirza