testing/test_monkeypatch.py

from __future__ import absolute_import, division, print_function
import os
import sys
import textwrap

import pytest
from _pytest.monkeypatch import MonkeyPatch


@pytest.fixture
def mp():
    cwd = os.getcwd()
    sys_path = list(sys.path)
    yield MonkeyPatch()
    sys.path[:] = sys_path
    os.chdir(cwd)


def test_setattr():
    class A(object):
        x = 1

    monkeypatch = MonkeyPatch()
    pytest.raises(AttributeError, "monkeypatch.setattr(A, 'notexists', 2)")
    monkeypatch.setattr(A, "y", 2, raising=False)
    assert A.y == 2
    monkeypatch.undo()
    assert not hasattr(A, "y")

    monkeypatch = MonkeyPatch()
    monkeypatch.setattr(A, "x", 2)
    assert A.x == 2
    monkeypatch.setattr(A, "x", 3)
    assert A.x == 3
    monkeypatch.undo()
    assert A.x == 1

    A.x = 5
    monkeypatch.undo()  # double-undo makes no modification
    assert A.x == 5


class TestSetattrWithImportPath(object):
    def test_string_expression(self, monkeypatch):
        monkeypatch.setattr("os.path.abspath", lambda x: "hello2")
        assert os.path.abspath("123") == "hello2"

    def test_string_expression_class(self, monkeypatch):
        monkeypatch.setattr("_pytest.config.Config", 42)
        import _pytest

        assert _pytest.config.Config == 42

    def test_unicode_string(self, monkeypatch):
        monkeypatch.setattr("_pytest.config.Config", 42)
        import _pytest

        assert _pytest.config.Config == 42
        monkeypatch.delattr("_pytest.config.Config")

    def test_wrong_target(self, monkeypatch):
        pytest.raises(TypeError, lambda: monkeypatch.setattr(None, None))

    def test_unknown_import(self, monkeypatch):
        pytest.raises(ImportError, lambda: monkeypatch.setattr("unkn123.classx", None))

    def test_unknown_attr(self, monkeypatch):
        pytest.raises(
            AttributeError, lambda: monkeypatch.setattr("os.path.qweqwe", None)
        )

    def test_unknown_attr_non_raising(self, monkeypatch):
        # https://github.com/pytest-dev/pytest/issues/746
        monkeypatch.setattr("os.path.qweqwe", 42, raising=False)
        assert os.path.qweqwe == 42

    def test_delattr(self, monkeypatch):
        monkeypatch.delattr("os.path.abspath")
        assert not hasattr(os.path, "abspath")
        monkeypatch.undo()
        assert os.path.abspath


def test_delattr():
    class A(object):
        x = 1

    monkeypatch = MonkeyPatch()
    monkeypatch.delattr(A, "x")
    assert not hasattr(A, "x")
    monkeypatch.undo()
    assert A.x == 1

    monkeypatch = MonkeyPatch()
    monkeypatch.delattr(A, "x")
    pytest.raises(AttributeError, "monkeypatch.delattr(A, 'y')")
    monkeypatch.delattr(A, "y", raising=False)
    monkeypatch.setattr(A, "x", 5, raising=False)
    assert A.x == 5
    monkeypatch.undo()
    assert A.x == 1


def test_setitem():
    d = {"x": 1}
    monkeypatch = MonkeyPatch()
    monkeypatch.setitem(d, "x", 2)
    monkeypatch.setitem(d, "y", 1700)
    monkeypatch.setitem(d, "y", 1700)
    assert d["x"] == 2
    assert d["y"] == 1700
    monkeypatch.setitem(d, "x", 3)
    assert d["x"] == 3
    monkeypatch.undo()
    assert d["x"] == 1
    assert "y" not in d
    d["x"] = 5
    monkeypatch.undo()
    assert d["x"] == 5


def test_setitem_deleted_meanwhile():
    d = {}
    monkeypatch = MonkeyPatch()
    monkeypatch.setitem(d, "x", 2)
    del d["x"]
    monkeypatch.undo()
    assert not d


@pytest.mark.parametrize("before", [True, False])
def test_setenv_deleted_meanwhile(before):
    key = "qwpeoip123"
    if before:
        os.environ[key] = "world"
    monkeypatch = MonkeyPatch()
    monkeypatch.setenv(key, "hello")
    del os.environ[key]
    monkeypatch.undo()
    if before:
        assert os.environ[key] == "world"
        del os.environ[key]
    else:
        assert key not in os.environ


def test_delitem():
    d = {"x": 1}
    monkeypatch = MonkeyPatch()
    monkeypatch.delitem(d, "x")
    assert "x" not in d
    monkeypatch.delitem(d, "y", raising=False)
    pytest.raises(KeyError, "monkeypatch.delitem(d, 'y')")
    assert not d
    monkeypatch.setitem(d, "y", 1700)
    assert d["y"] == 1700
    d["hello"] = "world"
    monkeypatch.setitem(d, "x", 1500)
    assert d["x"] == 1500
    monkeypatch.undo()
    assert d == {"hello": "world", "x": 1}


def test_setenv():
    monkeypatch = MonkeyPatch()
    monkeypatch.setenv("XYZ123", 2)
    import os

    assert os.environ["XYZ123"] == "2"
    monkeypatch.undo()
    assert "XYZ123" not in os.environ


def test_delenv():
    name = "xyz1234"
    assert name not in os.environ
    monkeypatch = MonkeyPatch()
    pytest.raises(KeyError, "monkeypatch.delenv(%r, raising=True)" % name)
    monkeypatch.delenv(name, raising=False)
    monkeypatch.undo()
    os.environ[name] = "1"
    try:
        monkeypatch = MonkeyPatch()
        monkeypatch.delenv(name)
        assert name not in os.environ
        monkeypatch.setenv(name, "3")
        assert os.environ[name] == "3"
        monkeypatch.undo()
        assert os.environ[name] == "1"
    finally:
        if name in os.environ:
            del os.environ[name]


def test_setenv_prepend():
    import os

    monkeypatch = MonkeyPatch()
    monkeypatch.setenv("XYZ123", 2, prepend="-")
    assert os.environ["XYZ123"] == "2"
    monkeypatch.setenv("XYZ123", 3, prepend="-")
    assert os.environ["XYZ123"] == "3-2"
    monkeypatch.undo()
    assert "XYZ123" not in os.environ


def test_monkeypatch_plugin(testdir):
    reprec = testdir.inline_runsource(
        """
        def test_method(monkeypatch):
            assert monkeypatch.__class__.__name__ == "MonkeyPatch"
    """
    )
    res = reprec.countoutcomes()
    assert tuple(res) == (1, 0, 0), res


def test_syspath_prepend(mp):
    old = list(sys.path)
    mp.syspath_prepend("world")
    mp.syspath_prepend("hello")
    assert sys.path[0] == "hello"
    assert sys.path[1] == "world"
    mp.undo()
    assert sys.path == old
    mp.undo()
    assert sys.path == old


def test_syspath_prepend_double_undo(mp):
    mp.syspath_prepend("hello world")
    mp.undo()
    sys.path.append("more hello world")
    mp.undo()
    assert sys.path[-1] == "more hello world"


def test_chdir_with_path_local(mp, tmpdir):
    mp.chdir(tmpdir)
    assert os.getcwd() == tmpdir.strpath


def test_chdir_with_str(mp, tmpdir):
    mp.chdir(tmpdir.strpath)
    assert os.getcwd() == tmpdir.strpath


def test_chdir_undo(mp, tmpdir):
    cwd = os.getcwd()
    mp.chdir(tmpdir)
    mp.undo()
    assert os.getcwd() == cwd


def test_chdir_double_undo(mp, tmpdir):
    mp.chdir(tmpdir.strpath)
    mp.undo()
    tmpdir.chdir()
    mp.undo()
    assert os.getcwd() == tmpdir.strpath


def test_issue185_time_breaks(testdir):
    testdir.makepyfile(
        """
        import time
        def test_m(monkeypatch):
            def f():
                raise Exception
            monkeypatch.setattr(time, "time", f)
    """
    )
    result = testdir.runpytest()
    result.stdout.fnmatch_lines(
        """
        *1 passed*
    """
    )


def test_importerror(testdir):
    p = testdir.mkpydir("package")
    p.join("a.py").write(
        textwrap.dedent(
            """\
        import doesnotexist

        x = 1
    """
        )
    )
    testdir.tmpdir.join("test_importerror.py").write(
        textwrap.dedent(
            """\
        def test_importerror(monkeypatch):
            monkeypatch.setattr('package.a.x', 2)
    """
        )
    )
    result = testdir.runpytest()
    result.stdout.fnmatch_lines(
        """
        *import error in package.a: No module named {0}doesnotexist{0}*
    """.format(
            "'" if sys.version_info > (3, 0) else ""
        )
    )


class SampleNew(object):
    @staticmethod
    def hello():
        return True


class SampleNewInherit(SampleNew):
    pass


class SampleOld(object):
    # oldstyle on python2
    @staticmethod
    def hello():
        return True


class SampleOldInherit(SampleOld):
    pass


@pytest.mark.parametrize(
    "Sample",
    [SampleNew, SampleNewInherit, SampleOld, SampleOldInherit],
    ids=["new", "new-inherit", "old", "old-inherit"],
)
def test_issue156_undo_staticmethod(Sample):
    monkeypatch = MonkeyPatch()

    monkeypatch.setattr(Sample, "hello", None)
    assert Sample.hello is None

    monkeypatch.undo()
    assert Sample.hello()


def test_issue1338_name_resolving():
    pytest.importorskip("requests")
    monkeypatch = MonkeyPatch()
    try:
        monkeypatch.delattr("requests.sessions.Session.request")
    finally:
        monkeypatch.undo()


def test_context():
    monkeypatch = MonkeyPatch()

    import functools
    import inspect

    with monkeypatch.context() as m:
        m.setattr(functools, "partial", 3)
        assert not inspect.isclass(functools.partial)
    assert inspect.isclass(functools.partial)