view tests/test-ctxmanager.py @ 28445:d749b1832d2f

revset: remove useless extpredicate class (API)

Previous patch makes this classes useless by replacing it with
revsetpredicate of registrar.

BTW, extpredicate itself has already been broken by that patch,
because revsetpredicate of registrar doesn't have compatibility with
original predicate (derived from funcregistrar of registrar), in fact.

from __future__ import absolute_import

import silenttestrunner
import unittest

from mercurial.util import ctxmanager

class contextmanager(object):
    def __init__(self, name, trace):
        self.name = name
        self.entered = False
        self.exited = False
        self.trace = trace

    def __enter__(self):
        self.entered = True
        self.trace(('enter', self.name))
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        self.exited = exc_type, exc_val, exc_tb
        self.trace(('exit', self.name))

    def __repr__(self):
        return '<ctx %r>' % self.name

class ctxerror(Exception):
    pass

class raise_on_enter(contextmanager):
    def __enter__(self):
        self.trace(('raise', self.name))
        raise ctxerror(self.name)

class raise_on_exit(contextmanager):
    def __exit__(self, exc_type, exc_val, exc_tb):
        self.trace(('raise', self.name))
        raise ctxerror(self.name)

def ctxmgr(name, trace):
    return lambda: contextmanager(name, trace)

class test_ctxmanager(unittest.TestCase):
    def test_basics(self):
        trace = []
        addtrace = trace.append
        with ctxmanager(ctxmgr('a', addtrace), ctxmgr('b', addtrace)) as c:
            a, b = c.enter()
            c.atexit(addtrace, ('atexit', 'x'))
            c.atexit(addtrace, ('atexit', 'y'))
        self.assertEqual(trace, [('enter', 'a'), ('enter', 'b'),
                                 ('atexit', 'y'), ('atexit', 'x'),
                                 ('exit', 'b'), ('exit', 'a')])

    def test_raise_on_enter(self):
        trace = []
        addtrace = trace.append
        def go():
            with ctxmanager(ctxmgr('a', addtrace),
                           lambda: raise_on_enter('b', addtrace)) as c:
                c.enter()
                addtrace('unreachable')
        self.assertRaises(ctxerror, go)
        self.assertEqual(trace, [('enter', 'a'), ('raise', 'b'), ('exit', 'a')])

    def test_raise_on_exit(self):
        trace = []
        addtrace = trace.append
        def go():
            with ctxmanager(ctxmgr('a', addtrace),
                           lambda: raise_on_exit('b', addtrace)) as c:
                c.enter()
                addtrace('running')
        self.assertRaises(ctxerror, go)
        self.assertEqual(trace, [('enter', 'a'), ('enter', 'b'), 'running',
                                 ('raise', 'b'), ('exit', 'a')])

if __name__ == '__main__':
    silenttestrunner.main(__name__)