tests/test-hgweb-diffs

Fix how setup.py identifies the Mercurial version.

There is a problem with setup.py where it will not identify the Mercurial
version properly when not being ran in within a repository even if
mercurial/__version__.py exists.

To fix, use mercurial.__version__.version when available before defaulting
to "unknown".  (Using mercurial.util.version() is not an option due to a
dependency issue where osutil can be referenced before it is built.)

echo % setting up repo
hg init test
cd test
echo a > a
echo b > b
hg ci -Ama

echo % change permissions for git diffs
chmod 755 a
hg ci -Amb

echo % set up hgweb
hg serve -n test -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log
cat hg.pid >> $DAEMON_PIDS

echo % revision
"$TESTDIR/get-with-headers.py" localhost:$HGPORT '/rev/0'

echo % diff removed file
"$TESTDIR/get-with-headers.py" localhost:$HGPORT '/diff/tip/a'

echo % set up hgweb with git diffs
"$TESTDIR/killdaemons.py"
hg serve --config 'diff.git=1' -n test -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log
cat hg.pid >> $DAEMON_PIDS

echo % revision
"$TESTDIR/get-with-headers.py" localhost:$HGPORT '/rev/0'

echo % diff removed file
"$TESTDIR/get-with-headers.py" localhost:$HGPORT '/diff/tip/a'

echo % errors
cat errors.log