tests: allow xrange warning from perf.py
The use of xrange in this file is acceptable.
We need to make the output optional - and not conditional on
the Python version - because `pyflakes` could be executed by any
Python version and pyflakes behaves differently depending on the
Python version.
Differential Revision: https://phab.mercurial-scm.org/D6990
#require test-repo pyflakes hg10
$ . "$TESTDIR/helpers-testrepo.sh"
run pyflakes on all tracked files ending in .py or without a file ending
(skipping binary file random-seed)
$ cat > test.py <<EOF
> print(undefinedname)
> EOF
$ pyflakes test.py 2>/dev/null | "$TESTDIR/filterpyflakes.py"
test.py:1: undefined name 'undefinedname'
$ cd "`dirname "$TESTDIR"`"
$ testrepohg locate 'set:**.py or grep("^#!.*python")' \
> -X hgext/fsmonitor/pywatchman \
> -X mercurial/pycompat.py -X contrib/python-zstandard \
> -X mercurial/thirdparty/cbor \
> -X mercurial/thirdparty/concurrent \
> -X mercurial/thirdparty/zope \
> 2>/dev/null \
> | xargs pyflakes 2>/dev/null | "$TESTDIR/filterpyflakes.py"
contrib/perf.py:*: undefined name 'xrange' (glob) (?)