360930 - test_file_protocol.js can fail based on execution environment

Status: RESOLVED FIXED

(Core :: Networking, defect)

Description

[Jeff Walden [:Waldo]]

test_file_protocol.js tests the file: protocol.  Among the ways in which it tests this is stream comparison of a file read through the protocol vs. a file read directly from disk.  To do the stream comparison, the test reads from the appropriate input stream into a string:

http://bonsai.mozilla.org/cvsblame.cgi?file=mozilla/netwerk/test/unit/test_file_protocol.js&rev=1.2&mark=42#29

The code which does this, however, can fail.  The highlighted line in the URL above theoretically works (albeit in a thoroughly horrendous manner), but it can fail in practice.  The reason for this is that SpiderMonkey restricts function calls to 65535 arguments.  This isn't often a problem, but one of the tests consists of checking for properly-formatted directory listings for the TmpD directory.  If /tmp contains an especially large number of files, the second iteration of read_stream will be called with a count of 65536 (first time is 4096).  This causes onDataAvailable to throw, which causes the isSuccessCode test in onStopRequest to fail, which causes the entire test to fail.

Patch in a sec...

Comment 1

[Jeff Walden [:Waldo]]

Attachment: Patch

Comment 2

[Jeff Walden [:Waldo]]

Attachment: Patch v2

Bah, this is why reviews are a good thing...

Comment 3

[Christian :Biesinger (don't email me, ping me on IRC)]

Comment on attachment 245775 [details] [diff] [review]
Patch v2

+      do_throw("Partial read from input stream!");

it's not so much partial but really nothing read, but whatever

Comment 4

[Jeff Walden [:Waldo]]

Fixed on trunk, with s/Partial/Nothing/.