tests/test-demandimport.py

graft: start using the cmdstate class to read and write data to graftstate

This patch replaces the logic to read and write data to graftstate file to use
the state.cmdstate() class.

The previous graftstate format didn't had any version number on top of that, so
we have to catch the CorruptedState error and then read the graftstate in case
of old state files.

This will help us to implement nice additions to graft commands like
`--no-commit`, `--abort`, `--stop` flags.

Passing on test-graft.t shows that things are working fine.

Differential Revision: https://phab.mercurial-scm.org/D3654

from __future__ import absolute_import, print_function

from mercurial import demandimport
demandimport.enable()

import os
import subprocess
import sys

# Only run if demandimport is allowed
if subprocess.call(['python', '%s/hghave' % os.environ['TESTDIR'],
                    'demandimport']):
    sys.exit(80)

if os.name != 'nt':
    try:
        import distutils.msvc9compiler
        print('distutils.msvc9compiler needs to be an immediate '
              'importerror on non-windows platforms')
        distutils.msvc9compiler
    except ImportError:
        pass

import re

rsub = re.sub
def f(obj):
    l = repr(obj)
    l = rsub("0x[0-9a-fA-F]+", "0x?", l)
    l = rsub("from '.*'", "from '?'", l)
    l = rsub("'<[a-z]*>'", "'<whatever>'", l)
    return l

demandimport.disable()
os.environ['HGDEMANDIMPORT'] = 'disable'
# this enable call should not actually enable demandimport!
demandimport.enable()
from mercurial import node
print("node =", f(node))
# now enable it for real
del os.environ['HGDEMANDIMPORT']
demandimport.enable()

# Test access to special attributes through demandmod proxy
from mercurial import error as errorproxy
print("errorproxy =", f(errorproxy))
print("errorproxy.__doc__ = %r"
      % (' '.join(errorproxy.__doc__.split()[:3]) + ' ...'))
print("errorproxy.__name__ = %r" % errorproxy.__name__)
# __name__ must be accessible via __dict__ so the relative imports can be
# resolved
print("errorproxy.__dict__['__name__'] = %r" % errorproxy.__dict__['__name__'])
print("errorproxy =", f(errorproxy))

import os

print("os =", f(os))
print("os.system =", f(os.system))
print("os =", f(os))

from mercurial.utils import procutil

print("procutil =", f(procutil))
print("procutil.system =", f(procutil.system))
print("procutil =", f(procutil))
print("procutil.system =", f(procutil.system))

from mercurial import hgweb
print("hgweb =", f(hgweb))
print("hgweb_mod =", f(hgweb.hgweb_mod))
print("hgweb =", f(hgweb))

import re as fred
print("fred =", f(fred))

import re as remod
print("remod =", f(remod))

import sys as re
print("re =", f(re))

print("fred =", f(fred))
print("fred.sub =", f(fred.sub))
print("fred =", f(fred))

remod.escape  # use remod
print("remod =", f(remod))

print("re =", f(re))
print("re.stderr =", f(re.stderr))
print("re =", f(re))

import contextlib
print("contextlib =", f(contextlib))
try:
    from contextlib import unknownattr
    print('no demandmod should be created for attribute of non-package '
          'module:\ncontextlib.unknownattr =', f(unknownattr))
except ImportError as inst:
    print('contextlib.unknownattr = ImportError: %s'
          % rsub(r"'", '', str(inst)))

from mercurial import util

# Unlike the import statement, __import__() function should not raise
# ImportError even if fromlist has an unknown item
# (see Python/import.c:import_module_level() and ensure_fromlist())
contextlibimp = __import__('contextlib', globals(), locals(), ['unknownattr'])
print("__import__('contextlib', ..., ['unknownattr']) =", f(contextlibimp))
print("hasattr(contextlibimp, 'unknownattr') =",
      util.safehasattr(contextlibimp, 'unknownattr'))