Feature or enhancement

Regular file objects returned by theopen() building havename andname andmode attributes. Some code may use these optional attributes for different purposes, for example to distinguish readable files from writable files, binary files from text files, or just for formatting the repr or error messages. For example:

• cpython/Lib/tarfile.py

  Line 1666 in5a83292

  if (nameisNoneandhasattr(fileobj,"name")and

• cpython/Lib/tarfile.py

  Line 1669 in5a83292

  ifhasattr(fileobj,"mode"):

• cpython/Lib/socket.py

  Line 455 in5a83292

  if'b'notingetattr(file,'mode','b'):

• cpython/Lib/gzip.py

  Line 201 in5a83292

  mode=getattr(fileobj,'mode','rb')

• cpython/Lib/asyncio/base_events.py

  Line 982 in5a83292

  if'b'notingetattr(file,'mode','b'):

• cpython/Lib/wave.py

  Line 654 in5a83292

  ifhasattr(f,'mode'):

There are several file-like objects in compressing modulesgzip,bz2 andlama and archiving moduleszipfile andtarfile. They usually implement the raw or buffered file protocols fromio, but not always havename andmode attributes, and when they have, they not always have common semantic.

GzipFile, unlike toBZ2File andLZMAFile, hasname andmode attributes, butmode is an integer, that confusestarfile (see#62775).

ZipExtFile has themode attribute which is always'r'. It is a legacy from Python 2, when it could also be'U' or'rU' for files with universal newlines. But this mode was removed long time ago, and since it is a binary file, its mode should be'rb'.

See also#68446,#91373,#91374. I opened this issue because consider it all the parts of larger image.

Linked PRs

• gh-115961: Improve tests for compressed file-like objects #115963
• [3.12] gh-115961: Improve tests for compressed file-like objects (GH-115963) #116032
• gh-115961: Add name and mode attributes for compressed file-like objects #116036
• [3.11] gh-115961: Improve tests for compressed file-like objects (GH-115963) #116039