tests/test-run-tests.py

revert: extract actual revert in its own function

With this small refactoring, the computation of the action to perform and the
actual change to the disk happen in different function. This allows extension to
wrap the later in case of need. The initial motivation is the `remotefilelog`
extension that need to prefetch all the file content to be checked out.

"""test line matching with some failing examples and some which warn

run-test.t only checks positive matches and can not see warnings
(both by design)
"""

import os, re
# this is hack to make sure no escape characters are inserted into the output
if 'TERM' in os.environ:
    del os.environ['TERM']
import doctest
run_tests = __import__('run-tests')

def lm(expected, output):
    r"""check if output matches expected

    does it generally work?
        >>> lm('H*e (glob)\n', 'Here\n')
        True

    fail on bad test data
        >>> try: lm('a\n','a')
        ... except AssertionError, ex: print ex
        missing newline
        >>> try: lm('single backslash\n', 'single \backslash\n')
        ... except AssertionError, ex: print ex
        single backslash or unknown char
    """
    assert expected.endswith('\n') and output.endswith('\n'), 'missing newline'
    assert not re.search(r'[^ \w\\/\r\n()*?]', expected + output), \
           'single backslash or unknown char'
    match = run_tests.linematch(expected, output)
    if isinstance(match, str):
        return 'special: ' + match
    else:
        return bool(match) # do not return match object

def wintests():
    r"""test matching like running on windows

    enable windows matching on any os
        >>> _osaltsep = os.altsep
        >>> os.altsep = True

    valid match on windows
        >>> lm('g/a*/d (glob)\n', 'g\\abc/d\n')
        True

    direct matching, glob unnecessary
        >>> lm('g/b (glob)\n', 'g/b\n')
        'special: -glob'

    missing glob
        >>> lm('/g/c/d/fg\n', '\\g\\c\\d/fg\n')
        'special: +glob'

    restore os.altsep
        >>> os.altsep = _osaltsep
    """
    pass

def otherostests():
    r"""test matching like running on non-windows os

    disable windows matching on any os
        >>> _osaltsep = os.altsep
        >>> os.altsep = False

    backslash does not match slash
        >>> lm('h/a* (glob)\n', 'h\\ab\n')
        False

    direct matching glob can not be recognized
        >>> lm('h/b (glob)\n', 'h/b\n')
        True

    missing glob can not not be recognized
        >>> lm('/h/c/df/g/\n', '\\h/c\\df/g\\\n')
        False

    restore os.altsep
        >>> os.altsep = _osaltsep
    """
    pass

if __name__ == '__main__':
    doctest.testmod()