interfaces: introduce and use a protocol class for the `bdiff` module
This is allowed by PEP 544[1], and we basically follow the example there. The
class here is copied from `mercurial.pure.bdiff`, and the implementation
removed.
There are several modules that have a few different implementations, and the
implementation chosen is controlled by `HGMODULEPOLICY`. The module is loaded
via `mercurial/policy.py`, and has been inferred by pytype as `Any` up to this
point. Therefore it and PyCharm were blind to all functions on the module, and
their signatures. Also, having multiple instances of the same module allows
their signatures to get out of sync.
Introducing a protocol class allows the loaded module that is stored in a
variable to be given type info, which cascades through the various places it is
used. This change alters 11 *.pyi files, for example. In theory, this would
also allow us to ensure the various implementations of the same module are kept
in alignment- simply import the module in a test module, attempt to pass it to a
function that uses the corresponding protocol as an argument, and run pytype on
it.
In practice, this doesn't work (yet). PyCharm (erroneously) flags imported
modules being passed where a protocol class is used[2]. Pytype has problems the
other way- it fails to detect when a module that doesn't adhere to the protocol
is passed to a protocol argument. The good news is that mypy properly detects
this case. The bad news is that mypy spews a bunch of other errors when
importing even simple modules, like the various `bdiff` modules. Therefore I'm
punting on the tests for now because the type info around a loaded module in
PyCharm is a clear win by itself.
[1] https://peps.python.org/pep-0544/#modules-as-implementations-of-protocols
[2] https://youtrack.jetbrains.com/issue/PY-58679/Support-modules-implementing-protocols
# Copyright 2020 Joerg Sonnenberger <joerg@bec.de>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""export repositories as git fast-import stream"""
# The format specification for fast-import streams can be found at
# https://git-scm.com/docs/git-fast-import#_input_format
from __future__ import annotations
import re
from mercurial.i18n import _
from mercurial.node import hex, nullrev
from mercurial.utils import stringutil
from mercurial import (
error,
logcmdutil,
registrar,
scmutil,
)
from .convert import convcmd
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = b"ships-with-hg-core"
cmdtable = {}
command = registrar.command(cmdtable)
GIT_PERSON_PROHIBITED = re.compile(b'[<>\n"]')
GIT_EMAIL_PROHIBITED = re.compile(b"[<> \n]")
def convert_to_git_user(authormap, user, rev):
mapped_user = authormap.get(user, user)
user_person = stringutil.person(mapped_user)
user_email = stringutil.email(mapped_user)
if GIT_EMAIL_PROHIBITED.match(user_email) or GIT_PERSON_PROHIBITED.match(
user_person
):
raise error.Abort(
_(b"Unable to parse user into person and email for revision %s")
% rev
)
if user_person:
return b'"%s" <%s>' % (user_person, user_email)
else:
return b"<%s>" % user_email
def convert_to_git_date(date):
timestamp, utcoff = date
tzsign = b"+" if utcoff <= 0 else b"-"
if utcoff % 60 != 0:
raise error.Abort(
_(b"UTC offset in %b is not an integer number of seconds") % (date,)
)
utcoff = abs(utcoff) // 60
tzh = utcoff // 60
tzmin = utcoff % 60
return b"%d " % int(timestamp) + tzsign + b"%02d%02d" % (tzh, tzmin)
def convert_to_git_ref(branch):
# XXX filter/map depending on git restrictions
return b"refs/heads/" + branch
def write_data(buf, data, add_newline=False):
buf.append(b"data %d\n" % len(data))
buf.append(data)
if add_newline or data[-1:] != b"\n":
buf.append(b"\n")
def export_commit(ui, repo, rev, marks, authormap):
ctx = repo[rev]
revid = ctx.hex()
if revid in marks:
ui.debug(b"warning: revision %s already exported, skipped\n" % revid)
return
parents = [p for p in ctx.parents() if p.rev() != nullrev]
for p in parents:
if p.hex() not in marks:
ui.warn(
_(b"warning: parent %s of %s has not been exported, skipped\n")
% (p, revid)
)
return
# For all files modified by the commit, check if they have already
# been exported and otherwise dump the blob with the new mark.
for fname in ctx.files():
if fname not in ctx:
continue
filectx = ctx.filectx(fname)
filerev = hex(filectx.filenode())
if filerev not in marks:
mark = len(marks) + 1
marks[filerev] = mark
data = filectx.data()
buf = [b"blob\n", b"mark :%d\n" % mark]
write_data(buf, data, True)
ui.write(*buf, keepprogressbar=True)
del buf
# Assign a mark for the current revision for references by
# latter merge commits.
mark = len(marks) + 1
marks[revid] = mark
ref = convert_to_git_ref(ctx.branch())
buf = [
b"commit %s\n" % ref,
b"mark :%d\n" % mark,
b"committer %s %s\n"
% (
convert_to_git_user(authormap, ctx.user(), revid),
convert_to_git_date(ctx.date()),
),
]
write_data(buf, ctx.description())
if parents:
buf.append(b"from :%d\n" % marks[parents[0].hex()])
if len(parents) == 2:
buf.append(b"merge :%d\n" % marks[parents[1].hex()])
p0ctx = repo[parents[0]]
files = ctx.manifest().diff(p0ctx.manifest())
else:
files = ctx.files()
filebuf = []
for fname in files:
if fname not in ctx:
filebuf.append((fname, b"D %s\n" % fname))
else:
filectx = ctx.filectx(fname)
filerev = filectx.filenode()
fileperm = b"755" if filectx.isexec() else b"644"
changed = b"M %s :%d %s\n" % (fileperm, marks[hex(filerev)], fname)
filebuf.append((fname, changed))
filebuf.sort()
buf.extend(changed for (fname, changed) in filebuf)
del filebuf
buf.append(b"\n")
ui.write(*buf, keepprogressbar=True)
del buf
isrev = re.compile(b"^[0-9a-f]{40}$")
@command(
b"fastexport",
[
(b"r", b"rev", [], _(b"revisions to export"), _(b"REV")),
(b"i", b"import-marks", b"", _(b"old marks file to read"), _(b"FILE")),
(b"e", b"export-marks", b"", _(b"new marks file to write"), _(b"FILE")),
(
b"A",
b"authormap",
b"",
_(b"remap usernames using this file"),
_(b"FILE"),
),
],
_(b"[OPTION]... [REV]..."),
helpcategory=command.CATEGORY_IMPORT_EXPORT,
)
def fastexport(ui, repo, *revs, **opts):
"""export repository as git fast-import stream
This command lets you dump a repository as a human-readable text stream.
It can be piped into corresponding import routines like "git fast-import".
Incremental dumps can be created by using marks files.
"""
revs += tuple(opts.get("rev", []))
if not revs:
revs = scmutil.revrange(repo, [b":"])
else:
revs = logcmdutil.revrange(repo, revs)
if not revs:
raise error.Abort(_(b"no revisions matched"))
authorfile = opts.get("authormap")
if authorfile:
authormap = convcmd.readauthormap(ui, authorfile)
else:
authormap = {}
import_marks = opts.get("import_marks")
marks = {}
if import_marks:
with open(import_marks, "rb") as import_marks_file:
for line in import_marks_file:
line = line.strip()
if not isrev.match(line) or line in marks:
raise error.Abort(_(b"Corrupted marks file"))
marks[line] = len(marks) + 1
revs.sort()
with ui.makeprogress(
_(b"exporting"), unit=_(b"revisions"), total=len(revs)
) as progress:
for rev in revs:
export_commit(ui, repo, rev, marks, authormap)
progress.increment()
export_marks = opts.get("export_marks")
if export_marks:
with open(export_marks, "wb") as export_marks_file:
output_marks = [None] * len(marks)
for k, v in marks.items():
output_marks[v - 1] = k
for k in output_marks:
export_marks_file.write(k + b"\n")