Skip to content

Commit

Permalink
pythongh-126565: Skip zipfile.Path.exists check in write mode (pyth…
Browse files Browse the repository at this point in the history
…onGH-126576)

When `zipfile.Path.open` is called, the implementation will check
whether the path already exists in the ZIP file. However, this check is
only required when the ZIP file is in read mode. By swapping arguments
of the `and` operator, the short-circuiting will prevent the check from
being run in write mode.

This change will improve the performance of `open()`, because checking
whether a file exists is slow in write mode, especially when the archive
has many members.
(cherry picked from commit 160758a)

Co-authored-by: Jan Hicken <janhicken@users.noreply.github.com>
  • Loading branch information
janhicken authored and miss-islington committed Nov 10, 2024
1 parent fa3ee75 commit ab1d6d7
Show file tree
Hide file tree
Showing 2 changed files with 2 additions and 1 deletion.
2 changes: 1 addition & 1 deletion Lib/zipfile/_path/__init__.py
Original file line number Diff line number Diff line change
Expand Up @@ -339,7 +339,7 @@ def open(self, mode='r', *args, pwd=None, **kwargs):
if self.is_dir():
raise IsADirectoryError(self)
zip_mode = mode[0]
if not self.exists() and zip_mode == 'r':
if zip_mode == 'r' and not self.exists():
raise FileNotFoundError(self)
stream = self.root.open(self.at, zip_mode, pwd=pwd)
if 'b' in mode:
Expand Down
Original file line number Diff line number Diff line change
@@ -0,0 +1 @@
Improve performances of :meth:`zipfile.Path.open` for non-reading modes.

0 comments on commit ab1d6d7

Please sign in to comment.