copies: filter out copies from non-existent source later in _chain()
_changesetforwardcopies() repeatedly calls _chain(). That is very
expensive because _chain() does lookups in the manifest. I hope to
split up the function in two parts: 1) simple chaining, not
considering end points, and 2) filter out files that don't exist in
the end points (and ping-pong copies/renames).
This patches gets us closer to that by moving the check for
non-existent source later in the function. Now there are no more
checks for "src" and "dst" in the first loop; all the filtering of
invalid copies is done in the second loop. The code also looks much
more consistent now.
No measureable impact on `hg debugpathcopies 4.0 4.8`. That shouldn't
be surprising since the only case we're doing more checks now is in
case of chained copies/renames, which are quire rare in practice.
Differential Revision: https://phab.mercurial-scm.org/D6277
from __future__ import absolute_import, print_function
# Import something from Mercurial, so the module loader gets initialized.
from mercurial import pycompat
del pycompat # unused for now
from hgext.lfs import pointer
def tryparse(text):
r = {}
try:
r = pointer.deserialize(text)
print('ok')
except Exception as ex:
print((b'%s' % ex).decode('ascii'))
if r:
text2 = r.serialize()
if text2 != text:
print('reconstructed text differs')
return r
t = (b'version https://git-lfs.github.com/spec/v1\n'
b'oid sha256:4d7a214614ab2935c943f9e0ff69d22eadbb8f32b1'
b'258daaa5e2ca24d17e2393\n'
b'size 12345\n'
b'x-foo extra-information\n')
tryparse(b'')
tryparse(t)
tryparse(t.replace(b'git-lfs', b'unknown'))
tryparse(t.replace(b'v1\n', b'v1\n\n'))
tryparse(t.replace(b'sha256', b'ahs256'))
tryparse(t.replace(b'sha256:', b''))
tryparse(t.replace(b'12345', b'0x12345'))
tryparse(t.replace(b'extra-information', b'extra\0information'))
tryparse(t.replace(b'extra-information', b'extra\ninformation'))
tryparse(t.replace(b'x-foo', b'x_foo'))
tryparse(t.replace(b'oid', b'blobid'))
tryparse(t.replace(b'size', b'size-bytes').replace(b'oid', b'object-id'))