git-filter-repo/t/t9391/unusual.py
Elijah Newren 88c1269d5a filter-repo: ensure branches are updated as we go
When we prune a commit for being empty, there is no update to the branch
associated with the commit in the fast-import stream.  If the parent
commit had been associated with a different branch, then the branch
associated with the pruned commit would not be updated without
additional measures.  In the past, we resolved this by recording that
the branch needed an update in _seen_refs.  While this works, it is a
bit more complicated than just issuing an immediate Reset.  Also, note
that we need to avoid calling callbacks on that Reset because those
could rename branches (again, if the commit-callback already renamed
once) causing us to not update the intended branch.

There was actually one testcase where the old method didn't work: when a
branch was pruned away to nothing.  A testcase accidentally encoded the
wrong behavior, hiding this problem.  Fix the testcase to check for
correct behavior.

Signed-off-by: Elijah Newren <newren@gmail.com>
2019-06-22 22:32:04 -06:00

129 lines
4.4 KiB
Python
Executable File

#!/usr/bin/env python3
# Please: DO NOT USE THIS AS AN EXAMPLE.
#
# This file is NOT for demonstration of how to use git-filter-repo as a
# libary; it exists to test corner cases or otherwise unusual inputs, and
# to verify some invariants that git-filter-repo currently aims to maintain
# (these invariants might be different in future versions of
# git-filter-repo). As such, it reaches deep into the internals and does
# weird things that you should probably avoid in your usage of
# git-filter-repo. Any code in this testcase is much more likely to have
# API breaks than other files in t9391.
import collections
import os
import random
import io
import sys
import textwrap
import git_filter_repo as fr
total_objects = {'common': 0, 'uncommon': 0}
def track_everything(obj, *_ignored):
if type(obj) == fr.Blob or type(obj) == fr.Commit:
total_objects['common'] += 1
else:
total_objects['uncommon'] += 1
if type(obj) == fr.Reset:
def assert_not_reached(x): raise SystemExit("should have been skipped!")
obj.dump = assert_not_reached
obj.skip()
if hasattr(obj, 'id'):
# The creation of myblob should cause objects in stream to get their ids
# increased by 1; this shouldn't be depended upon as API by external
# projects, I'm just verifying an invariant of the current code.
assert fr._IDS._reverse_translation[obj.id] == [obj.id - 1]
def handle_progress(progress):
print(b"Decipher this: "+bytes(reversed(progress.message)))
track_everything(progress)
def handle_checkpoint(checkpoint_object):
# Flip a coin; see if we want to pass the checkpoint through.
if random.randint(0,1) == 0:
checkpoint_object.dump(parser._output)
track_everything(checkpoint_object)
mystr = b'This is the contents of the blob'
compare = b"Blob:\n blob\n mark :1\n data %d\n %s" % (len(mystr), mystr)
# Next line's only purpose is testing code coverage of something that helps
# debugging git-filter-repo; it is NOT something external folks should depend
# upon.
myblob = fr.Blob(mystr)
assert bytes(myblob) == compare
# Everyone should be using RepoFilter objects, not FastExportParser. But for
# testing purposes...
parser = fr.FastExportParser(blob_callback = track_everything,
reset_callback = track_everything,
commit_callback = track_everything,
tag_callback = track_everything,
progress_callback = handle_progress,
checkpoint_callback = handle_checkpoint)
parser.run(input = sys.stdin.detach(),
output = open(os.devnull, 'bw'))
# DO NOT depend upon or use _IDS directly you external script writers. I'm
# only testing here for code coverage; the capacity exists to help debug
# git-filter-repo itself, not for external folks to use.
assert str(fr._IDS).startswith("Current count: 4")
print("Found {} blobs/commits and {} other objects"
.format(total_objects['common'], total_objects['uncommon']))
stream = io.BytesIO(textwrap.dedent('''
blob
mark :1
data 5
hello
commit refs/heads/A
mark :2
author Just Me <just@here.org> 1234567890 -0200
committer Just Me <just@here.org> 1234567890 -0200
data 2
A
commit refs/heads/B
mark :3
author Just Me <just@here.org> 1234567890 -0200
committer Just Me <just@here.org> 1234567890 -0200
data 2
B
from :2
M 100644 :1 greeting
commit refs/heads/C
mark :4
author Just Me <just@here.org> 1234567890 -0200
committer Just Me <just@here.org> 1234567890 -0200
data 2
C
from :3
M 100644 :1 salutation
'''[1:]).encode())
counts = collections.Counter()
def look_for_reset(obj, metadata):
print("Processing {}".format(obj))
counts[type(obj)] += 1
if type(obj) == fr.Reset:
assert obj.ref == b'refs/heads/B'
# Use all kinds of internals that external scripts should NOT use and which
# are likely to break in the future, just to verify a few invariants...
args = fr.FilteringOptions.parse_args(['--stdin', '--dry-run',
'--path', 'salutation'])
filter = fr.RepoFilter(args,
blob_callback = look_for_reset,
reset_callback = look_for_reset,
commit_callback = look_for_reset,
tag_callback = look_for_reset)
filter._input = stream
filter._setup_output()
filter._sanity_checks_handled = True
filter.run()
assert counts == collections.Counter({fr.Blob: 1, fr.Commit: 3})