test_utils.py

import copy
import filecmp
import os
import tarfile
import zipfile
from collections import deque
from io import BytesIO

import pytest

from requests import compat
from requests._internal_utils import unicode_is_ascii
from requests.cookies import RequestsCookieJar
from requests.structures import CaseInsensitiveDict
from requests.utils import (
    _parse_content_type_header,
    add_dict_to_cookiejar,
    address_in_network,
    dotted_netmask,
    extract_zipped_paths,
    get_auth_from_url,
    get_encoding_from_headers,
    get_encodings_from_content,
    get_environ_proxies,
    guess_filename,
    guess_json_utf,
    is_ipv4_address,
    is_valid_cidr,
    iter_slices,
    parse_dict_header,
    parse_header_links,
    prepend_scheme_if_needed,
    requote_uri,
    select_proxy,
    set_environ,
    should_bypass_proxies,
    super_len,
    to_key_val_list,
    to_native_string,
    unquote_header_value,
    unquote_unreserved,
    urldefragauth,
)

from .compat import StringIO, cStringIO


class TestSuperLen:
    @pytest.mark.parametrize(
        "stream, value",
        (
            (StringIO.StringIO, "Test"),
            (BytesIO, b"Test"),
            pytest.param(
                cStringIO, "Test", marks=pytest.mark.skipif("cStringIO is None")
            ),
        ),
    )
    def test_io_streams(self, stream, value):
        """Ensures that we properly deal with different kinds of IO streams."""
        assert super_len(stream()) == 0
        assert super_len(stream(value)) == 4

    def test_super_len_correctly_calculates_len_of_partially_read_file(self):
        """Ensure that we handle partially consumed file like objects."""
        s = StringIO.StringIO()
        s.write("foobarbogus")
        assert super_len(s) == 0

    @pytest.mark.parametrize("error", [IOError, OSError])
    def test_super_len_handles_files_raising_weird_errors_in_tell(self, error):
        """If tell() raises errors, assume the cursor is at position zero."""

        class BoomFile:
            def __len__(self):
                return 5

            def tell(self):
                raise error()

        assert super_len(BoomFile()) == 0

    @pytest.mark.parametrize("error", [IOError, OSError])
    def test_super_len_tell_ioerror(self, error):
        """Ensure that if tell gives an IOError super_len doesn't fail"""

        class NoLenBoomFile:
            def tell(self):
                raise error()

            def seek(self, offset, whence):
                pass

        assert super_len(NoLenBoomFile()) == 0

    def test_string(self):
        assert super_len("Test") == 4

    @pytest.mark.parametrize(
        "mode, warnings_num",
        (
            ("r", 1),
            ("rb", 0),
        ),
    )
    def test_file(self, tmpdir, mode, warnings_num, recwarn):
        file_obj = tmpdir.join("test.txt")
        file_obj.write("Test")
        with file_obj.open(mode) as fd:
            assert super_len(fd) == 4
        assert len(recwarn) == warnings_num

    def test_tarfile_member(self, tmpdir):
        file_obj = tmpdir.join("test.txt")
        file_obj.write("Test")

        tar_obj = str(tmpdir.join("test.tar"))
        with tarfile.open(tar_obj, "w") as tar:
            tar.add(str(file_obj), arcname="test.txt")

        with tarfile.open(tar_obj) as tar:
            member = tar.extractfile("test.txt")
            assert super_len(member) == 4

    def test_super_len_with__len__(self):
        foo = [1, 2, 3, 4]
        len_foo = super_len(foo)
        assert len_foo == 4

    def test_super_len_with_no__len__(self):
        class LenFile:
            def __init__(self):
                self.len = 5

        assert super_len(LenFile()) == 5

    def test_super_len_with_tell(self):
        foo = StringIO.StringIO("12345")
        assert super_len(foo) == 5
        foo.read(2)
        assert super_len(foo) == 3

    def test_super_len_with_fileno(self):
        with open(__file__, "rb") as f:
            length = super_len(f)
            file_data = f.read()
        assert length == len(file_data)

    def test_super_len_with_no_matches(self):
        """Ensure that objects without any length methods default to 0"""
        assert super_len(object()) == 0


class TestToKeyValList:
    @pytest.mark.parametrize(
        "value, expected",
        (
            ([("key", "val")], [("key", "val")]),
            ((("key", "val"),), [("key", "val")]),
            ({"key": "val"}, [("key", "val")]),
            (None, None),
        ),
    )
    def test_valid(self, value, expected):
        assert to_key_val_list(value) == expected

    def test_invalid(self):
        with pytest.raises(ValueError):
            to_key_val_list("string")


class TestUnquoteHeaderValue:
    @pytest.mark.parametrize(
        "value, expected",
        (
            (None, None),
            ("Test", "Test"),
            ('"Test"', "Test"),
            ('"Test\\\\"', "Test\\"),
            ('"\\\\Comp\\Res"', "\\Comp\\Res"),
        ),
    )
    def test_valid(self, value, expected):
        assert unquote_header_value(value) == expected

    def test_is_filename(self):
        assert unquote_header_value('"\\\\Comp\\Res"', True) == "\\\\Comp\\Res"


class TestGetEnvironProxies:
    """Ensures that IP addresses are correctly matches with ranges
    in no_proxy variable.
    """

    @pytest.fixture(autouse=True, params=["no_proxy", "NO_PROXY"])
    def no_proxy(self, request, monkeypatch):
        monkeypatch.setenv(
            request.param, "192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1"
        )

    @pytest.mark.parametrize(
        "url",
        (
            "http://192.168.0.1:5000/",
            "http://192.168.0.1/",
            "http://172.16.1.1/",
            "http://172.16.1.1:5000/",
            "http://localhost.localdomain:5000/v1.0/",
        ),
    )
    def test_bypass(self, url):
        assert get_environ_proxies(url, no_proxy=None) == {}

    @pytest.mark.parametrize(
        "url",
        (
            "http://192.168.1.1:5000/",
            "http://192.168.1.1/",
            "http://www.requests.com/",
        ),
    )
    def test_not_bypass(self, url):
        assert get_environ_proxies(url, no_proxy=None) != {}

    @pytest.mark.parametrize(
        "url",
        (
            "http://192.168.1.1:5000/",
            "http://192.168.1.1/",
            "http://www.requests.com/",
        ),
    )
    def test_bypass_no_proxy_keyword(self, url):
        no_proxy = "192.168.1.1,requests.com"
        assert get_environ_proxies(url, no_proxy=no_proxy) == {}

    @pytest.mark.parametrize(
        "url",
        (
            "http://192.168.0.1:5000/",
            "http://192.168.0.1/",
            "http://172.16.1.1/",
            "http://172.16.1.1:5000/",
            "http://localhost.localdomain:5000/v1.0/",
        ),
    )
    def test_not_bypass_no_proxy_keyword(self, url, monkeypatch):
        # This is testing that the 'no_proxy' argument overrides the
        # environment variable 'no_proxy'
        monkeypatch.setenv("http_proxy", "http://proxy.example.com:3128/")
        no_proxy = "192.168.1.1,requests.com"
        assert get_environ_proxies(url, no_proxy=no_proxy) != {}


class TestIsIPv4Address:
    def test_valid(self):
        assert is_ipv4_address("8.8.8.8")

    @pytest.mark.parametrize("value", ("8.8.8.8.8", "localhost.localdomain"))
    def test_invalid(self, value):
        assert not is_ipv4_address(value)


class TestIsValidCIDR:
    def test_valid(self):
        assert is_valid_cidr("192.168.1.0/24")

    @pytest.mark.parametrize(
        "value",
        (
            "8.8.8.8",
            "192.168.1.0/a",
            "192.168.1.0/128",
            "192.168.1.0/-1",
            "192.168.1.999/24",
        ),
    )
    def test_invalid(self, value):
        assert not is_valid_cidr(value)


class TestAddressInNetwork:
    def test_valid(self):
        assert address_in_network("192.168.1.1", "192.168.1.0/24")

    def test_invalid(self):
        assert not address_in_network("172.16.0.1", "192.168.1.0/24")


class TestGuessFilename:
    @pytest.mark.parametrize(
        "value",
        (1, type("Fake", (object,), {"name": 1})()),
    )
    def test_guess_filename_invalid(self, value):
        assert guess_filename(value) is None

    @pytest.mark.parametrize(
        "value, expected_type",
        (
            (b"value", compat.bytes),
            (b"value".decode("utf-8"), compat.str),
        ),
    )
    def test_guess_filename_valid(self, value, expected_type):
        obj = type("Fake", (object,), {"name": value})()
        result = guess_filename(obj)
        assert result == value
        assert isinstance(result, expected_type)


class TestExtractZippedPaths:
    @pytest.mark.parametrize(
        "path",
        (
            "/",
            __file__,
            pytest.__file__,
            "/etc/invalid/location",
        ),
    )
    def test_unzipped_paths_unchanged(self, path):
        assert path == extract_zipped_paths(path)

    def test_zipped_paths_extracted(self, tmpdir):
        zipped_py = tmpdir.join("test.zip")
        with zipfile.ZipFile(zipped_py.strpath, "w") as f:
            f.write(__file__)

        _, name = os.path.splitdrive(__file__)
        zipped_path = os.path.join(zipped_py.strpath, name.lstrip(r"\/"))
        extracted_path = extract_zipped_paths(zipped_path)

        assert extracted_path != zipped_path
        assert os.path.exists(extracted_path)
        assert filecmp.cmp(extracted_path, __file__)

    def test_invalid_unc_path(self):
        path = r"\\localhost\invalid\location"
        assert extract_zipped_paths(path) == path


class TestContentEncodingDetection:
    def test_none(self):
        encodings = get_encodings_from_content("")
        assert not len(encodings)

    @pytest.mark.parametrize(
        "content",
        (
            # HTML5 meta charset attribute
            '<meta charset="UTF-8">',
            # HTML4 pragma directive
            '<meta http-equiv="Content-type" content="text/html;charset=UTF-8">',
            # XHTML 1.x served with text/html MIME type
            '<meta http-equiv="Content-type" content="text/html;charset=UTF-8" />',
            # XHTML 1.x served as XML
            '<?xml version="1.0" encoding="UTF-8"?>',
        ),
    )
    def test_pragmas(self, content):
        encodings = get_encodings_from_content(content)
        assert len(encodings) == 1
        assert encodings[0] == "UTF-8"

    def test_precedence(self):
        content = """
        <?xml version="1.0" encoding="XML"?>
        <meta charset="HTML5">
        <meta http-equiv="Content-type" content="text/html;charset=HTML4" />
        """.strip()
        assert get_encodings_from_content(content) == ["HTML5", "HTML4", "XML"]


class TestGuessJSONUTF:
    @pytest.mark.parametrize(
        "encoding",
        (
            "utf-32",
            "utf-8-sig",
            "utf-16",
            "utf-8",
            "utf-16-be",
            "utf-16-le",
            "utf-32-be",
            "utf-32-le",
        ),
    )
    def test_encoded(self, encoding):
        data = "{}".encode(encoding)
        assert guess_json_utf(data) == encoding

    def test_bad_utf_like_encoding(self):
        assert guess_json_utf(b"\x00\x00\x00\x00") is None

    @pytest.mark.parametrize(
        ("encoding", "expected"),
        (
            ("utf-16-be", "utf-16"),
            ("utf-16-le", "utf-16"),
            ("utf-32-be", "utf-32"),
            ("utf-32-le", "utf-32"),
        ),
    )
    def test_guess_by_bom(self, encoding, expected):
        data = "\ufeff{}".encode(encoding)
        assert guess_json_utf(data) == expected


USER = PASSWORD = "%!*'();:@&=+$,/?#[] "
ENCODED_USER = compat.quote(USER, "")
ENCODED_PASSWORD = compat.quote(PASSWORD, "")


@pytest.mark.parametrize(
    "url, auth",
    (
        (
            f"http://{ENCODED_USER}:{ENCODED_PASSWORD}@request.com/url.html#test",
            (USER, PASSWORD),
        ),
        ("http://user:pass@complex.url.com/path?query=yes", ("user", "pass")),
        (
            "http://user:pass%20pass@complex.url.com/path?query=yes",
            ("user", "pass pass"),
        ),
        ("http://user:pass pass@complex.url.com/path?query=yes", ("user", "pass pass")),
        (
            "http://user%25user:pass@complex.url.com/path?query=yes",
            ("user%user", "pass"),
        ),
        (
            "http://user:pass%23pass@complex.url.com/path?query=yes",
            ("user", "pass#pass"),
        ),
        ("http://complex.url.com/path?query=yes", ("", "")),
    ),
)
def test_get_auth_from_url(url, auth):
    assert get_auth_from_url(url) == auth


@pytest.mark.parametrize(
    "uri, expected",
    (
        (
            # Ensure requoting doesn't break expectations
            "http://example.com/fiz?buz=%25ppicture",
            "http://example.com/fiz?buz=%25ppicture",
        ),
        (
            # Ensure we handle unquoted percent signs in redirects
            "http://example.com/fiz?buz=%ppicture",
            "http://example.com/fiz?buz=%25ppicture",
        ),
    ),
)
def test_requote_uri_with_unquoted_percents(uri, expected):
    """See: https://github.com/psf/requests/issues/2356"""
    assert requote_uri(uri) == expected


@pytest.mark.parametrize(
    "uri, expected",
    (
        (
            # Illegal bytes
            "http://example.com/?a=%--",
            "http://example.com/?a=%--",
        ),
        (
            # Reserved characters
            "http://example.com/?a=%300",
            "http://example.com/?a=00",
        ),
    ),
)
def test_unquote_unreserved(uri, expected):
    assert unquote_unreserved(uri) == expected


@pytest.mark.parametrize(
    "mask, expected",
    (
        (8, "255.0.0.0"),
        (24, "255.255.255.0"),
        (25, "255.255.255.128"),
    ),
)
def test_dotted_netmask(mask, expected):
    assert dotted_netmask(mask) == expected


http_proxies = {
    "http": "http://http.proxy",
    "http://some.host": "http://some.host.proxy",
}
all_proxies = {
    "all": "socks5://http.proxy",
    "all://some.host": "socks5://some.host.proxy",
}
mixed_proxies = {
    "http": "http://http.proxy",
    "http://some.host": "http://some.host.proxy",
    "all": "socks5://http.proxy",
}


@pytest.mark.parametrize(
    "url, expected, proxies",
    (
        ("hTTp://u:p@Some.Host/path", "http://some.host.proxy", http_proxies),
        ("hTTp://u:p@Other.Host/path", "http://http.proxy", http_proxies),
        ("hTTp:///path", "http://http.proxy", http_proxies),
        ("hTTps://Other.Host", None, http_proxies),
        ("file:///etc/motd", None, http_proxies),
        ("hTTp://u:p@Some.Host/path", "socks5://some.host.proxy", all_proxies),
        ("hTTp://u:p@Other.Host/path", "socks5://http.proxy", all_proxies),
        ("hTTp:///path", "socks5://http.proxy", all_proxies),
        ("hTTps://Other.Host", "socks5://http.proxy", all_proxies),
        ("http://u:p@other.host/path", "http://http.proxy", mixed_proxies),
        ("http://u:p@some.host/path", "http://some.host.proxy", mixed_proxies),
        ("https://u:p@other.host/path", "socks5://http.proxy", mixed_proxies),
        ("https://u:p@some.host/path", "socks5://http.proxy", mixed_proxies),
        ("https://", "socks5://http.proxy", mixed_proxies),
        # XXX: unsure whether this is reasonable behavior
        ("file:///etc/motd", "socks5://http.proxy", all_proxies),
    ),
)
def test_select_proxies(url, expected, proxies):
    """Make sure we can select per-host proxies correctly."""
    assert select_proxy(url, proxies) == expected


@pytest.mark.parametrize(
    "value, expected",
    (
        ('foo="is a fish", bar="as well"', {"foo": "is a fish", "bar": "as well"}),
        ("key_without_value", {"key_without_value": None}),
    ),
)
def test_parse_dict_header(value, expected):
    assert parse_dict_header(value) == expected


@pytest.mark.parametrize(
    "value, expected",
    (
        ("application/xml", ("application/xml", {})),
        (
            "application/json ; charset=utf-8",
            ("application/json", {"charset": "utf-8"}),
        ),
        (
            "application/json ; Charset=utf-8",
            ("application/json", {"charset": "utf-8"}),
        ),
        ("text/plain", ("text/plain", {})),
        (
            "multipart/form-data; boundary = something ; boundary2='something_else' ; no_equals ",
            (
                "multipart/form-data",
                {
                    "boundary": "something",
                    "boundary2": "something_else",
                    "no_equals": True,
                },
            ),
        ),
        (
            'multipart/form-data; boundary = something ; boundary2="something_else" ; no_equals ',
            (
                "multipart/form-data",
                {
                    "boundary": "something",
                    "boundary2": "something_else",
                    "no_equals": True,
                },
            ),
        ),
        (
            "multipart/form-data; boundary = something ; 'boundary2=something_else' ; no_equals ",
            (
                "multipart/form-data",
                {
                    "boundary": "something",
                    "boundary2": "something_else",
                    "no_equals": True,
                },
            ),
        ),
        (
            'multipart/form-data; boundary = something ; "boundary2=something_else" ; no_equals ',
            (
                "multipart/form-data",
                {
                    "boundary": "something",
                    "boundary2": "something_else",
                    "no_equals": True,
                },
            ),
        ),
        ("application/json ; ; ", ("application/json", {})),
    ),
)
def test__parse_content_type_header(value, expected):
    assert _parse_content_type_header(value) == expected


@pytest.mark.parametrize(
    "value, expected",
    (
        (CaseInsensitiveDict(), None),
        (
            CaseInsensitiveDict({"content-type": "application/json; charset=utf-8"}),
            "utf-8",
        ),
        (CaseInsensitiveDict({"content-type": "text/plain"}), "ISO-8859-1"),
    ),
)
def test_get_encoding_from_headers(value, expected):
    assert get_encoding_from_headers(value) == expected


@pytest.mark.parametrize(
    "value, length",
    (
        ("", 0),
        ("T", 1),
        ("Test", 4),
        ("Cont", 0),
        ("Other", -5),
        ("Content", None),
    ),
)
def test_iter_slices(value, length):
    if length is None or (length <= 0 and len(value) > 0):
        # Reads all content at once
        assert len(list(iter_slices(value, length))) == 1
    else:
        assert len(list(iter_slices(value, 1))) == length


@pytest.mark.parametrize(
    "value, expected",
    (
        (
            '<http:/.../front.jpeg>; rel=front; type="image/jpeg"',
            [{"url": "http:/.../front.jpeg", "rel": "front", "type": "image/jpeg"}],
        ),
        ("<http:/.../front.jpeg>", [{"url": "http:/.../front.jpeg"}]),
        ("<http:/.../front.jpeg>;", [{"url": "http:/.../front.jpeg"}]),
        (
            '<http:/.../front.jpeg>; type="image/jpeg",<http://.../back.jpeg>;',
            [
                {"url": "http:/.../front.jpeg", "type": "image/jpeg"},
                {"url": "http://.../back.jpeg"},
            ],
        ),
        ("", []),
    ),
)
def test_parse_header_links(value, expected):
    assert parse_header_links(value) == expected


@pytest.mark.parametrize(
    "value, expected",
    (
        ("example.com/path", "http://example.com/path"),
        ("//example.com/path", "http://example.com/path"),
        ("example.com:80", "http://example.com:80"),
        (
            "http://user:pass@example.com/path?query",
            "http://user:pass@example.com/path?query",
        ),
        ("http://user@example.com/path?query", "http://user@example.com/path?query"),
    ),
)
def test_prepend_scheme_if_needed(value, expected):
    assert prepend_scheme_if_needed(value, "http") == expected


@pytest.mark.parametrize(
    "value, expected",
    (
        ("T", "T"),
        (b"T", "T"),
        ("T", "T"),
    ),
)
def test_to_native_string(value, expected):
    assert to_native_string(value) == expected


@pytest.mark.parametrize(
    "url, expected",
    (
        ("http://u:p@example.com/path?a=1#test", "http://example.com/path?a=1"),
        ("http://example.com/path", "http://example.com/path"),
        ("//u:p@example.com/path", "//example.com/path"),
        ("//example.com/path", "//example.com/path"),
        ("example.com/path", "//example.com/path"),
        ("scheme:u:p@example.com/path", "scheme://example.com/path"),
    ),
)
def test_urldefragauth(url, expected):
    assert urldefragauth(url) == expected


@pytest.mark.parametrize(
    "url, expected",
    (
        ("http://192.168.0.1:5000/", True),
        ("http://192.168.0.1/", True),
        ("http://172.16.1.1/", True),
        ("http://172.16.1.1:5000/", True),
        ("http://localhost.localdomain:5000/v1.0/", True),
        ("http://google.com:6000/", True),
        ("http://172.16.1.12/", False),
        ("http://172.16.1.12:5000/", False),
        ("http://google.com:5000/v1.0/", False),
        ("file:///some/path/on/disk", True),
    ),
)
def test_should_bypass_proxies(url, expected, monkeypatch):
    """Tests for function should_bypass_proxies to check if proxy
    can be bypassed or not
    """
    monkeypatch.setenv(
        "no_proxy",
        "192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1, google.com:6000",
    )
    monkeypatch.setenv(
        "NO_PROXY",
        "192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1, google.com:6000",
    )
    assert should_bypass_proxies(url, no_proxy=None) == expected


@pytest.mark.parametrize(
    "url, expected",
    (
        ("http://172.16.1.1/", "172.16.1.1"),
        ("http://172.16.1.1:5000/", "172.16.1.1"),
        ("http://user:pass@172.16.1.1", "172.16.1.1"),
        ("http://user:pass@172.16.1.1:5000", "172.16.1.1"),
        ("http://hostname/", "hostname"),
        ("http://hostname:5000/", "hostname"),
        ("http://user:pass@hostname", "hostname"),
        ("http://user:pass@hostname:5000", "hostname"),
    ),
)
def test_should_bypass_proxies_pass_only_hostname(url, expected, mocker):
    """The proxy_bypass function should be called with a hostname or IP without
    a port number or auth credentials.
    """
    proxy_bypass = mocker.patch("requests.utils.proxy_bypass")
    should_bypass_proxies(url, no_proxy=None)
    proxy_bypass.assert_called_once_with(expected)


@pytest.mark.parametrize(
    "cookiejar",
    (
        compat.cookielib.CookieJar(),
        RequestsCookieJar(),
    ),
)
def test_add_dict_to_cookiejar(cookiejar):
    """Ensure add_dict_to_cookiejar works for
    non-RequestsCookieJar CookieJars
    """
    cookiedict = {"test": "cookies", "good": "cookies"}
    cj = add_dict_to_cookiejar(cookiejar, cookiedict)
    cookies = {cookie.name: cookie.value for cookie in cj}
    assert cookiedict == cookies


@pytest.mark.parametrize(
    "value, expected",
    (
        ("test", True),
        ("æíöû", False),
        ("ジェーピーニック", False),
    ),
)
def test_unicode_is_ascii(value, expected):
    assert unicode_is_ascii(value) is expected


@pytest.mark.parametrize(
    "url, expected",
    (
        ("http://192.168.0.1:5000/", True),
        ("http://192.168.0.1/", True),
        ("http://172.16.1.1/", True),
        ("http://172.16.1.1:5000/", True),
        ("http://localhost.localdomain:5000/v1.0/", True),
        ("http://172.16.1.12/", False),
        ("http://172.16.1.12:5000/", False),
        ("http://google.com:5000/v1.0/", False),
    ),
)
def test_should_bypass_proxies_no_proxy(url, expected, monkeypatch):
    """Tests for function should_bypass_proxies to check if proxy
    can be bypassed or not using the 'no_proxy' argument
    """
    no_proxy = "192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1"
    # Test 'no_proxy' argument
    assert should_bypass_proxies(url, no_proxy=no_proxy) == expected


@pytest.mark.skipif(os.name != "nt", reason="Test only on Windows")
@pytest.mark.parametrize(
    "url, expected, override",
    (
        ("http://192.168.0.1:5000/", True, None),
        ("http://192.168.0.1/", True, None),
        ("http://172.16.1.1/", True, None),
        ("http://172.16.1.1:5000/", True, None),
        ("http://localhost.localdomain:5000/v1.0/", True, None),
        ("http://172.16.1.22/", False, None),
        ("http://172.16.1.22:5000/", False, None),
        ("http://google.com:5000/v1.0/", False, None),
        ("http://mylocalhostname:5000/v1.0/", True, "<local>"),
        ("http://192.168.0.1/", False, ""),
    ),
)
def test_should_bypass_proxies_win_registry(url, expected, override, monkeypatch):
    """Tests for function should_bypass_proxies to check if proxy
    can be bypassed or not with Windows registry settings
    """
    if override is None:
        override = "192.168.*;127.0.0.1;localhost.localdomain;172.16.1.1"
    import winreg

    class RegHandle:
        def Close(self):
            pass

    ie_settings = RegHandle()
    proxyEnableValues = deque([1, "1"])

    def OpenKey(key, subkey):
        return ie_settings

    def QueryValueEx(key, value_name):
        if key is ie_settings:
            if value_name == "ProxyEnable":
                # this could be a string (REG_SZ) or a 32-bit number (REG_DWORD)
                proxyEnableValues.rotate()
                return [proxyEnableValues[0]]
            elif value_name == "ProxyOverride":
                return [override]

    monkeypatch.setenv("http_proxy", "")
    monkeypatch.setenv("https_proxy", "")
    monkeypatch.setenv("ftp_proxy", "")
    monkeypatch.setenv("no_proxy", "")
    monkeypatch.setenv("NO_PROXY", "")
    monkeypatch.setattr(winreg, "OpenKey", OpenKey)
    monkeypatch.setattr(winreg, "QueryValueEx", QueryValueEx)
    assert should_bypass_proxies(url, None) == expected


@pytest.mark.skipif(os.name != "nt", reason="Test only on Windows")
def test_should_bypass_proxies_win_registry_bad_values(monkeypatch):
    """Tests for function should_bypass_proxies to check if proxy
    can be bypassed or not with Windows invalid registry settings.
    """
    import winreg

    class RegHandle:
        def Close(self):
            pass

    ie_settings = RegHandle()

    def OpenKey(key, subkey):
        return ie_settings

    def QueryValueEx(key, value_name):
        if key is ie_settings:
            if value_name == "ProxyEnable":
                # Invalid response; Should be an int or int-y value
                return [""]
            elif value_name == "ProxyOverride":
                return ["192.168.*;127.0.0.1;localhost.localdomain;172.16.1.1"]

    monkeypatch.setenv("http_proxy", "")
    monkeypatch.setenv("https_proxy", "")
    monkeypatch.setenv("no_proxy", "")
    monkeypatch.setenv("NO_PROXY", "")
    monkeypatch.setattr(winreg, "OpenKey", OpenKey)
    monkeypatch.setattr(winreg, "QueryValueEx", QueryValueEx)
    assert should_bypass_proxies("http://172.16.1.1/", None) is False


@pytest.mark.parametrize(
    "env_name, value",
    (
        ("no_proxy", "192.168.0.0/24,127.0.0.1,localhost.localdomain"),
        ("no_proxy", None),
        ("a_new_key", "192.168.0.0/24,127.0.0.1,localhost.localdomain"),
        ("a_new_key", None),
    ),
)
def test_set_environ(env_name, value):
    """Tests set_environ will set environ values and will restore the environ."""
    environ_copy = copy.deepcopy(os.environ)
    with set_environ(env_name, value):
        assert os.environ.get(env_name) == value

    assert os.environ == environ_copy


def test_set_environ_raises_exception():
    """Tests set_environ will raise exceptions in context when the
    value parameter is None."""
    with pytest.raises(Exception) as exception:
        with set_environ("test1", None):
            raise Exception("Expected exception")

    assert "Expected exception" in str(exception.value)