New submission from David Haney <david.ha...@gmail.com>:
The implementation of open relies on a codecs' IncrementalEncoder, however it never calls `encode` with final=True. This appears to violate the documentation for IncrementalEncoder.encode which states that the last call to encode _must_ set final=True. The attached test case demonstrates this behavior. A codec "delayed" is implemented that holds the last encoded string until the next call to `encode`, at which point it returns the encoded string. When final=True, both the previous and current string are returned. When `codecs.iterencode` is used to encode a sequence of strings, the encode function is called for each element in the sequence, with final=False. encode is then called a final time with an empty string and final=True. When `open` is used to open a file stream for the encoding, each call to `write` calls `encode` with final=False, however it never calls `encode` with final=True, and it doesn't appear there's an API for forcing it to occur (for instance `flush` and `close` do not). ---------- components: IO files: test.py messages: 332701 nosy: haney priority: normal severity: normal status: open title: open doesn't call IncrementalEncoder with final=True type: behavior versions: Python 3.7 Added file: https://bugs.python.org/file48022/test.py _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue35611> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com