tests/hghave

hgweb: always return iterable from @webcommand functions (API)

We had to hack up this function to support our transition to the
new response API. Now that we're done with the transition (!!),
we can return to returning an iterator of content chunks from
these functions.

It is tempting to return a normal object and not a generator.
However, as the keyword extension demonstrates, extensions may
wish to wrap commands and have a try..finally block around
execution. Since there is a generator producing content and
that generator could be executing code, the try..finally needs
to live for as long as the generator is running. That means we
have to return a generator so wrappers can consume the generator
inside a try..finally.

.. api::

   hgweb @webcommand functions must use the new response object
   passed in via ``web.res`` to initiate sending of a response.
   The hgweb WSGI application will no longer start sending the
   response automatically.

Differential Revision: https://phab.mercurial-scm.org/D2796

#!/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.
"""

from __future__ import absolute_import, print_function

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)