windows: prevent bytes from being passed to registry APIs
There was a TortoiseHg bug report in this area[1], and from inspection, it looks
like passing `b""` as `valname` would fail to convert to unicode. The
underlying API allows both `""` and `NULL` to return the default value for the
key.
[1] https://foss.heptapod.net/mercurial/tortoisehg/thg/-/issues/5803
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# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
# no unicode literals
import sys
"""Compatibility module across Python 2 and 3."""
PYTHON2 = sys.version_info < (3, 0)
PYTHON3 = sys.version_info >= (3, 0)
# This is adapted from https://bitbucket.org/gutworth/six, and used under the
# MIT license. See LICENSE for a full copyright notice.
if PYTHON3:
def reraise(tp, value, tb=None):
try:
if value is None:
value = tp()
if value.__traceback__ is not tb:
raise value.with_traceback(tb)
raise value
finally:
value = None
tb = None
else:
exec(
"""
def reraise(tp, value, tb=None):
try:
raise tp, value, tb
finally:
tb = None
""".strip()
)
if PYTHON3:
UNICODE = str
else:
UNICODE = unicode # noqa: F821 We handled versioning above