templates: add filter to reverse list
The filter supports only lists because for lists, it’s straightforward to
implement. Reversing text doesn’t seem very useful and is hard to implement.
Reversing the bytes would break multi-bytes encodings. Reversing the code
points would break characters consisting of multiple code points. Reversing
graphemes is non-trivial without using a library not included in the standard
library.
#!/usr/bin/env python
"""Test the running system for features availability. Exit with zero
if all features are there, non-zero otherwise. If a feature name is
prefixed with "no-", the absence of feature is tested.
"""
import hghave
import optparse
import os
import sys
checks = hghave.checks
def list_features():
for name, feature in sorted(checks.items()):
desc = feature[1]
print(name + ':', desc)
def test_features():
failed = 0
for name, feature in checks.items():
check, _ = feature
try:
check()
except Exception as e:
print("feature %s failed: %s" % (name, e))
failed += 1
return failed
parser = optparse.OptionParser("%prog [options] [features]")
parser.add_option(
"--test-features", action="store_true", help="test available features"
)
parser.add_option(
"--list-features", action="store_true", help="list available features"
)
def _loadaddon():
if 'TESTDIR' in os.environ:
# loading from '.' isn't needed, because `hghave` should be
# running at TESTTMP in this case
path = os.environ['TESTDIR']
else:
path = '.'
if not os.path.exists(os.path.join(path, 'hghaveaddon.py')):
return
sys.path.insert(0, path)
try:
import hghaveaddon
assert hghaveaddon # silence pyflakes
except BaseException as inst:
sys.stderr.write(
'failed to import hghaveaddon.py from %r: %s\n' % (path, inst)
)
sys.exit(2)
sys.path.pop(0)
if __name__ == '__main__':
options, args = parser.parse_args()
_loadaddon()
if options.list_features:
list_features()
sys.exit(0)
if options.test_features:
sys.exit(test_features())
hghave.require(args)