unpack requires a string argument of length 1

[Clark Boylan]

With the recent release of python-subunit 0.0.14 some of our python27 unittests have begun failing with a "unpack requires a string argument of length 1" message (http://logs.openstack.org/37/43537/1/check/gate-zuul-python27/44a6863/console.html). Downgrading the python-subunit package to version 0.0.13 corrects the problem.

For what it is worth these error does not seem to occur under python 2.6 (http://logs.openstack.org/37/43537/1/check/gate-zuul-python26/a36aadc/console.html).

You can reproduce this locally by git cloning https://git.openstack.org/openstack-infra/zuul and running `tox -epy27` in the root dir of that project.

[Clark Boylan (cboylan)]

I neglected to mention that the unittests are being run by testr which forks subunit.run. The error seems to occur when running `testr list-tests` as well.

[Robert Collins (lifeless)]

nuts. Will look at it asapish.

[Robert Collins (lifeless)]

=== modified file 'python/subunit/v2.py'
--- python/subunit/v2.py 2013-08-23 21:47:28 +0000
+++ python/subunit/v2.py 2013-08-24 12:31:59 +0000
@@ -385,8 +385,10 @@
                         % (crc, packet_crc))
             if safe_hasattr(builtins, 'memoryview'):
                 body = memoryview(packet[-1])
+ view = True
             else:
                 body = packet[-1]
+ view = False
             # Discard CRC-32
             body = body[:-4]
             # One packet could have both file and status data; the Python API
@@ -421,6 +423,8 @@
                 content_length, consumed = self._parse_varint(body, pos)
                 pos += consumed
                 file_bytes = body[pos:pos+content_length]
+ if view:
+ file_bytes = file_bytes.tobytes()
                 if len(file_bytes) != content_length:
                     raise ParseError('File content extends past end of packet: '
                         'claimed %d bytes, %d available' % (

may help, though I can't yet reproduce the problem.

[ZhiQiang Fan (aji-zqfan)]

Thanks for your update, i modify the file and test it in
python-neutronclient via `tox -e py27`, but doesn't work. Need more
confirmation.

On Sat, Aug 24, 2013 at 8:41 PM, Robert Collins
<email address hidden>wrote:

> === modified file 'python/subunit/v2.py'
> --- python/subunit/v2.py 2013-08-23 21:47:28 +0000
> +++ python/subunit/v2.py 2013-08-24 12:31:59 +0000
> @@ -385,8 +385,10 @@
> % (crc, packet_crc))
> if safe_hasattr(builtins, 'memoryview'):
> body = memoryview(packet[-1])
> + view = True
> else:
> body = packet[-1]
> + view = False
> # Discard CRC-32
> body = body[:-4]
> # One packet could have both file and status data; the Python
> API
> @@ -421,6 +423,8 @@
> content_length, consumed = self._parse_varint(body, pos)
> pos += consumed
> file_bytes = body[pos:pos+content_length]
> + if view:
> + file_bytes = file_bytes.tobytes()
> if len(file_bytes) != content_length:
> raise ParseError('File content extends past end of
> packet: '
> 'claimed %d bytes, %d available' % (
>
>
> may help, though I can't yet reproduce the problem.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1216163
>
> Title:
> unpack requires a string argument of length 1
>
> Status in SubUnit:
> New
>
> Bug description:
> With the recent release of python-subunit 0.0.14 some of our python27
> unittests have begun failing with a "unpack requires a string argument
> of length 1" message (http://logs.openstack.org/37/43537/1/check/gate-
> zuul-python27/44a6863/console.html). Downgrading the python-subunit
> package to version 0.0.13 corrects the problem.
>
> For what it is worth these error does not seem to occur under python
> 2.6 (http://logs.openstack.org/37/43537/1/check/gate-zuul-
> python26/a36aadc/console.html).
>
> You can reproduce this locally by git cloning
> https://git.openstack.org/openstack-infra/zuul and running `tox
> -epy27` in the root dir of that project.
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/subunit/+bug/1216163/+subscriptions
>

--
blog: zqfan.github.com
git: github.com/zqfan

[Robert Collins (lifeless)]

2.7.3 shows the problem, 2.7.5 doesn't; 3.2 does. I suspect memoryview and struct being incompatible in those releases :(

[ZhiQiang Fan (aji-zqfan)]

yes, my python version is 2.7.3, confirmed, thank you.

[Jay Buffington (jaybuff)]

For the record, this bug manifested itself for me with this error message:
    sequence item 15: expected string, memoryview found

This is with python 2.7.5