dulwich.pack.DeltaChainIterator

class documentation

class DeltaChainIterator(Generic[T]):

Known subclasses: dulwich.pack.PackIndexer, dulwich.pack.PackInflater, dulwich.pack.UnpackedObjectIterator

Constructor: DeltaChainIterator(file_obj, hash_func, resolve_ext_ref)

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Abstract iterator over pack data based on delta chains.

Each object in the pack is guaranteed to be inflated exactly once, regardless of how many objects reference it as a delta base. As a result, memory usage is proportional to the length of the longest delta chain.

Subclasses can override _result to define the result type of the iterator. By default, results are UnpackedObjects with the following members set:

  • offset
  • obj_type_num
  • obj_chunks
  • pack_type_num
  • delta_base (for delta types)
  • comp_chunks (if _include_comp is True)
  • decomp_chunks
  • decomp_len
  • crc32 (if _compute_crc32 is True)
Class Method for_pack_data Create a DeltaChainIterator from pack data.
Class Method for_pack_subset Create a DeltaChainIterator for a subset of objects.
Method __init__ Initialize DeltaChainIterator.
Method __iter__ Iterate over objects in the pack.
Method ext_refs Return external references.
Method record Record an unpacked object for later processing.
Method set_pack_data Set the pack data for iteration.
Instance Variable hash_func Undocumented
Method _ensure_no_pending Undocumented
Method _follow_chain Undocumented
Method _resolve_object Undocumented
Method _result Undocumented
Method _walk_all_chains Undocumented
Method _walk_ref_chains Undocumented
Class Variable _compute_crc32 Undocumented
Class Variable _include_comp Undocumented
Instance Variable _ext_refs Undocumented
Instance Variable _file Undocumented
Instance Variable _full_ofs Undocumented
Instance Variable _pending_ofs Undocumented
Instance Variable _pending_ref Undocumented
Instance Variable _resolve_ext_ref Undocumented
def for_pack_data(cls, pack_data: PackData, resolve_ext_ref: ResolveExtRefFn | None = None) -> DeltaChainIterator[T]:

Create a DeltaChainIterator from pack data.

Parameters
pack_data:PackDataPackData object to iterate
resolve_ext_ref:ResolveExtRefFn | NoneOptional function to resolve external refs
Returns
DeltaChainIterator[T]DeltaChainIterator instance
def for_pack_subset(cls, pack: Pack, shas: Iterable[ObjectID | RawObjectID], *, allow_missing: bool = False, resolve_ext_ref: ResolveExtRefFn | None = None) -> DeltaChainIterator[T]:

Create a DeltaChainIterator for a subset of objects.

Parameters
pack:PackPack object containing the data
shas:Iterable[ObjectID | RawObjectID]Iterable of object SHAs to include
allow_missing:boolIf True, skip missing objects
resolve_ext_ref:ResolveExtRefFn | NoneOptional function to resolve external refs
Returns
DeltaChainIterator[T]DeltaChainIterator instance
def __init__(self, file_obj: IO[bytes] | None, hash_func: Callable[[], HashObject], *, resolve_ext_ref: ResolveExtRefFn | None = None):

Initialize DeltaChainIterator.

Parameters
file_obj:IO[bytes] | NoneFile object to read pack data from
hash_func:Callable[[], HashObject]Hash function to use for computing object IDs
resolve_ext_ref:ResolveExtRefFn | NoneOptional function to resolve external references
def __iter__(self) -> Iterator[T]:

Iterate over objects in the pack.

def ext_refs(self) -> list[RawObjectID]:

Return external references.

def record(self, unpacked: UnpackedObject):

Record an unpacked object for later processing.

Parameters
unpacked:UnpackedObjectUnpackedObject to record
def set_pack_data(self, pack_data: PackData):

Set the pack data for iteration.

Parameters
pack_data:PackDataPackData object to use
hash_func =

Undocumented

def _ensure_no_pending(self):

Undocumented

def _follow_chain(self, offset: int, obj_type_num: int, base_chunks: list[bytes] | None) -> Iterator[T]:

Undocumented

def _resolve_object(self, offset: int, obj_type_num: int, base_chunks: list[bytes] | None) -> UnpackedObject:

Undocumented

def _result(self, unpacked: UnpackedObject) -> T:
overridden in dulwich.pack.PackIndexer, dulwich.pack.PackInflater, dulwich.pack.UnpackedObjectIterator

Undocumented

def _walk_all_chains(self) -> Iterator[T]:

Undocumented

def _walk_ref_chains(self) -> Iterator[T]:

Undocumented

_compute_crc32: bool =
overridden in dulwich.pack.PackIndexer

Undocumented

_include_comp: bool =

Undocumented

_ext_refs: list[RawObjectID] =

Undocumented

_file =

Undocumented

_full_ofs: list[tuple[int, int]] =

Undocumented

_pending_ofs: dict[int, list[int]] =

Undocumented

_pending_ref: dict[bytes, list[int]] =

Undocumented

_resolve_ext_ref =

Undocumented