tests/test-doctest.py

rust-cpython: prepare for writing tests that require libpython

What I wanted is to disable the "cpython/extension-module<ver>" feature
while building tests executable, but that seems not doable. Instead,
this patch adds new features dedicated for tests.

The make rule is extracted so that we can easily run cargo tests.

Added a minimal test of ref-sharing as an example. More tests will follow.

# this is hack to make sure no escape characters are inserted into the output

from __future__ import absolute_import

import doctest
import os
import re
import sys

ispy3 = sys.version_info[0] >= 3

if 'TERM' in os.environ:
    del os.environ['TERM']


class py3docchecker(doctest.OutputChecker):
    def check_output(self, want, got, optionflags):
        want2 = re.sub(r'''\bu(['"])(.*?)\1''', r'\1\2\1', want)  # py2: u''
        got2 = re.sub(r'''\bb(['"])(.*?)\1''', r'\1\2\1', got)  # py3: b''
        # py3: <exc.name>: b'<msg>' -> <name>: <msg>
        #      <exc.name>: <others> -> <name>: <others>
        got2 = re.sub(
            r'''^mercurial\.\w+\.(\w+): (['"])(.*?)\2''',
            r'\1: \3',
            got2,
            re.MULTILINE,
        )
        got2 = re.sub(r'^mercurial\.\w+\.(\w+): ', r'\1: ', got2, re.MULTILINE)
        return any(
            doctest.OutputChecker.check_output(self, w, g, optionflags)
            for w, g in [(want, got), (want2, got2)]
        )


def testmod(name, optionflags=0, testtarget=None):
    __import__(name)
    mod = sys.modules[name]
    if testtarget is not None:
        mod = getattr(mod, testtarget)

    # minimal copy of doctest.testmod()
    finder = doctest.DocTestFinder()
    checker = None
    if ispy3:
        checker = py3docchecker()
    runner = doctest.DocTestRunner(checker=checker, optionflags=optionflags)
    for test in finder.find(mod, name):
        runner.run(test)
    runner.summarize()


testmod('mercurial.changegroup')
testmod('mercurial.changelog')
testmod('mercurial.cmdutil')
testmod('mercurial.color')
testmod('mercurial.config')
testmod('mercurial.context')
testmod('mercurial.dagparser', optionflags=doctest.NORMALIZE_WHITESPACE)
testmod('mercurial.dispatch')
testmod('mercurial.encoding')
testmod('mercurial.fancyopts')
testmod('mercurial.formatter')
testmod('mercurial.hg')
testmod('mercurial.hgweb.hgwebdir_mod')
testmod('mercurial.match')
testmod('mercurial.mdiff')
testmod('mercurial.minirst')
testmod('mercurial.patch')
testmod('mercurial.pathutil')
testmod('mercurial.parser')
testmod('mercurial.pycompat')
testmod('mercurial.revlog')
testmod('mercurial.revlogutils.deltas')
testmod('mercurial.revset')
testmod('mercurial.revsetlang')
testmod('mercurial.smartset')
testmod('mercurial.store')
testmod('mercurial.subrepo')
testmod('mercurial.templatefilters')
testmod('mercurial.templater')
testmod('mercurial.ui')
testmod('mercurial.url')
testmod('mercurial.util')
testmod('mercurial.util', testtarget='platform')
testmod('mercurial.utils.stringutil')
testmod('hgext.convert.convcmd')
testmod('hgext.convert.cvsps')
testmod('hgext.convert.filemap')
testmod('hgext.convert.p4')
testmod('hgext.convert.subversion')
testmod('hgext.fix')
testmod('hgext.mq')
# Helper scripts in tests/ that have doctests:
testmod('drawdag')