templates: add filter to reverse list
The filter supports only lists because for lists, it’s straightforward to
implement. Reversing text doesn’t seem very useful and is hard to implement.
Reversing the bytes would break multi-bytes encodings. Reversing the code
points would break characters consisting of multiple code points. Reversing
graphemes is non-trivial without using a library not included in the standard
library.
# 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'))