view tests/test-atomictempfile.py @ 44763:94f4f2ec7dee stable

packaging: support building Inno installer with PyOxidizer

We want to start distributing Mercurial on Python 3 on
Windows. PyOxidizer will be our vehicle for achieving that.

This commit implements basic support for producing Inno
installers using PyOxidizer.

While it is an eventual goal of PyOxidizer to produce
installers, those features aren't yet implemented. So our
strategy for producing Mercurial installers is similar to
what we've been doing with py2exe: invoke a build system to
produce files then stage those files into a directory so they
can be turned into an installer.

We had to make significant alterations to the pyoxidizer.bzl
config file to get it to produce the files that we desire for
a Windows install. This meant differentiating the build targets
so we can target Windows specifically.

We've added a new module to hgpackaging to deal with interacting
with PyOxidizer. It is similar to pyexe: we invoke a build process
then copy files to a staging directory. Ideally these extra
files would be defined in pyoxidizer.bzl. But I don't think it
is worth doing at this time, as PyOxidizer's config files are
lacking some features to make this turnkey.

The rest of the change is introducing a variant of the
Inno installer code that invokes PyOxidizer instead of
py2exe.

Comparing the Python 2.7 based Inno installers with this
one, the following changes were observed:

* No lib/*.{pyd, dll} files
* No Microsoft.VC90.CRT.manifest
* No msvc{m,p,r}90.dll files
* python27.dll replaced with python37.dll
* Add vcruntime140.dll file

The disappearance of the .pyd and .dll files is acceptable, as
PyOxidizer has embedded these in hg.exe and loads them from
memory.

The disappearance of the *90* files is acceptable because those
provide the Visual C++ 9 runtime, as required by Python 2.7.
Similarly, the appearance of vcruntime140.dll is a requirement
of Python 3.7.

Differential Revision: https://phab.mercurial-scm.org/D8473

from __future__ import absolute_import

import glob
import os
import shutil
import stat
import tempfile
import unittest

from mercurial import (
    pycompat,
    util,
)

atomictempfile = util.atomictempfile

if pycompat.ispy3:
    xrange = range


class testatomictempfile(unittest.TestCase):
    def setUp(self):
        self._testdir = tempfile.mkdtemp(b'atomictempfiletest')
        self._filename = os.path.join(self._testdir, b'testfilename')

    def tearDown(self):
        shutil.rmtree(self._testdir, True)

    def testsimple(self):
        file = atomictempfile(self._filename)
        self.assertFalse(os.path.isfile(self._filename))
        tempfilename = file._tempname
        self.assertTrue(
            tempfilename
            in glob.glob(os.path.join(self._testdir, b'.testfilename-*'))
        )

        file.write(b'argh\n')
        file.close()

        self.assertTrue(os.path.isfile(self._filename))
        self.assertTrue(
            tempfilename
            not in glob.glob(os.path.join(self._testdir, b'.testfilename-*'))
        )

    # discard() removes the temp file without making the write permanent
    def testdiscard(self):
        file = atomictempfile(self._filename)
        (dir, basename) = os.path.split(file._tempname)

        file.write(b'yo\n')
        file.discard()

        self.assertFalse(os.path.isfile(self._filename))
        self.assertTrue(basename not in os.listdir(b'.'))

    # if a programmer screws up and passes bad args to atomictempfile, they
    # get a plain ordinary TypeError, not infinite recursion
    def testoops(self):
        with self.assertRaises(TypeError):
            atomictempfile()

    # checkambig=True avoids ambiguity of timestamp
    def testcheckambig(self):
        def atomicwrite(checkambig):
            f = atomictempfile(self._filename, checkambig=checkambig)
            f.write(b'FOO')
            f.close()

        # try some times, because reproduction of ambiguity depends on
        # "filesystem time"
        for i in xrange(5):
            atomicwrite(False)
            oldstat = os.stat(self._filename)
            if oldstat[stat.ST_CTIME] != oldstat[stat.ST_MTIME]:
                # subsequent changing never causes ambiguity
                continue

            repetition = 3

            # repeat atomic write with checkambig=True, to examine
            # whether st_mtime is advanced multiple times as expected
            for j in xrange(repetition):
                atomicwrite(True)
            newstat = os.stat(self._filename)
            if oldstat[stat.ST_CTIME] != newstat[stat.ST_CTIME]:
                # timestamp ambiguity was naturally avoided while repetition
                continue

            # st_mtime should be advanced "repetition" times, because
            # all atomicwrite() occurred at same time (in sec)
            oldtime = (oldstat[stat.ST_MTIME] + repetition) & 0x7FFFFFFF
            self.assertTrue(newstat[stat.ST_MTIME] == oldtime)
            # no more examination is needed, if assumption above is true
            break
        else:
            # This platform seems too slow to examine anti-ambiguity
            # of file timestamp (or test happened to be executed at
            # bad timing). Exit silently in this case, because running
            # on other faster platforms can detect problems
            pass

    def testread(self):
        with open(self._filename, 'wb') as f:
            f.write(b'foobar\n')
        file = atomictempfile(self._filename, mode=b'rb')
        self.assertTrue(file.read(), b'foobar\n')
        file.discard()

    def testcontextmanagersuccess(self):
        """When the context closes, the file is closed"""
        with atomictempfile(b'foo') as f:
            self.assertFalse(os.path.isfile(b'foo'))
            f.write(b'argh\n')
        self.assertTrue(os.path.isfile(b'foo'))

    def testcontextmanagerfailure(self):
        """On exception, the file is discarded"""
        try:
            with atomictempfile(b'foo') as f:
                self.assertFalse(os.path.isfile(b'foo'))
                f.write(b'argh\n')
                raise ValueError
        except ValueError:
            pass
        self.assertFalse(os.path.isfile(b'foo'))


if __name__ == '__main__':
    import silenttestrunner

    silenttestrunner.main(__name__)