def partial_to_complete_sha(self, partial_binsha, canonical_length):
""":return: 20 byte sha as inferred by the given partial binary sha
:param partial_binsha: binary sha with less than 20 bytes
:param canonical_length: length of the corresponding canonical representation.
It is required as binary sha's cannot display whether the original hex sha
had an odd or even number of characters
:raise AmbiguousObjectName:
:raise BadObject: """
candidate = None
for item in self._entities:
item_index = item[1].index().partial_sha_to_index(
partial_binsha, canonical_length)
if item_index is not None:
sha = item[1].index().sha(item_index)
if candidate and candidate != sha:
raise AmbiguousObjectName(partial_binsha)
candidate = sha
# END handle full sha could be found
# END for each entity
if candidate:
return candidate
# still not found ?
raise BadObject(partial_binsha)
def partial_sha_to_index(self, partial_bin_sha, canonical_length):
"""
:return: index as in `sha_to_index` or None if the sha was not found in this
index file
:param partial_bin_sha: an at least two bytes of a partial binary sha as bytes
:param canonical_length: length of the original hexadecimal representation of the
given partial binary sha
:raise AmbiguousObjectName:"""
if len(partial_bin_sha) < 2:
raise ValueError("Require at least 2 bytes of partial sha")
assert isinstance(partial_bin_sha,
bytes), "partial_bin_sha must be bytes"
first_byte = byte_ord(partial_bin_sha[0])
get_sha = self.sha
lo = 0 # lower index, the left bound of the bisection
if first_byte != 0:
lo = self._fanout_table[first_byte - 1]
hi = self._fanout_table[
first_byte] # the upper, right bound of the bisection
# fill the partial to full 20 bytes
filled_sha = partial_bin_sha + NULL_BYTE * (20 - len(partial_bin_sha))
# find lowest
while lo < hi:
mid = (lo + hi) // 2
mid_sha = get_sha(mid)
if filled_sha < mid_sha:
hi = mid
elif filled_sha == mid_sha:
# perfect match
lo = mid
break
else:
lo = mid + 1
# END handle midpoint
# END bisect
if lo < self.size():
cur_sha = get_sha(lo)
if is_equal_canonical_sha(canonical_length, partial_bin_sha,
cur_sha):
next_sha = None
if lo + 1 < self.size():
next_sha = get_sha(lo + 1)
if next_sha and next_sha == cur_sha:
raise AmbiguousObjectName(partial_bin_sha)
return lo
# END if we have a match
# END if we found something
return None
def partial_to_complete_sha_hex(self, partial_hexsha):
""":return: 20 byte binary sha1 string which matches the given name uniquely
:param name: hexadecimal partial name
:raise AmbiguousObjectName:
:raise BadObject: """
candidate = None
for binsha in self.sha_iter():
if bin_to_hex(binsha).startswith(partial_hexsha):
# it can't ever find the same object twice
if candidate is not None:
raise AmbiguousObjectName(partial_hexsha)
candidate = binsha
# END for each object
if candidate is None:
raise BadObject(partial_hexsha)
return candidate
def partial_to_complete_sha_hex(self, partial_hexsha):
"""
:return: 20 byte binary sha1 from the given less-than-40 byte hexsha
:param partial_hexsha: hexsha with less than 40 byte
:raise AmbiguousObjectName: """
databases = list()
_databases_recursive(self, databases)
len_partial_hexsha = len(partial_hexsha)
if len_partial_hexsha % 2 != 0:
partial_binsha = hex_to_bin(partial_hexsha + "0")
else:
partial_binsha = hex_to_bin(partial_hexsha)
# END assure successful binary conversion
candidate = None
for db in databases:
full_bin_sha = None
try:
if hasattr(db, 'partial_to_complete_sha_hex'):
full_bin_sha = db.partial_to_complete_sha_hex(
partial_hexsha)
else:
full_bin_sha = db.partial_to_complete_sha(
partial_binsha, len_partial_hexsha)
# END handle database type
except BadObject:
continue
# END ignore bad objects
if full_bin_sha:
if candidate and candidate != full_bin_sha:
raise AmbiguousObjectName(partial_hexsha)
candidate = full_bin_sha
# END handle candidate
# END for each db
if not candidate:
raise BadObject(partial_binsha)
return candidate