Inconsistent documentation of tell/seek on textiobase/textiowrapper

[qha]

BPO	38788
Nosy	@terryjreedy, @qha

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2019-11-13.14:36:28.180>
labels = ['3.8', 'library']
title = 'Inconsistent documentation of tell/seek on textiobase/textiowrapper'
updated_at = <Date 2019-11-15.20:28:43.659>
user = 'https://github.com/qha'

bugs.python.org fields:

activity = <Date 2019-11-15.20:28:43.659>
actor = 'terry.reedy'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2019-11-13.14:36:28.180>
creator = 'qha'
dependencies = []
files = []
hgrepos = []
issue_num = 38788
keywords = []
message_count = 1.0
messages = ['356534']
nosy_count = 2.0
nosy_names = ['terry.reedy', 'qha']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = None
url = 'https://bugs.python.org/issue38788'
versions = ['Python 3.8']

[qha]

The class hierarchy suggests the only tell/seek implementations one
needs to look up are in iobase and those have the semantics i was
expecting:
https://docs.python.org/3.8/library/io.html#class-hierarchy

Plowing on one might discover that there are separate implementations
of tell/seek for textiobase whose documentation probably explains the
unexpected values tell returns.

The documentation for tell available from the help() command still
reflects the semantics i was expecting.

The documentation for seek available from the help() command still
reflects the semantics i was expecting. It does however suggest that
the first argument has been renamed from offset to cookie which the
online documentation has not yet caught up to at:
https://docs.python.org/3.8/library/io.html#io.TextIOBase.seek

The documentation body for seek from the help() command still refers to
offset though there is now no argument of that name.

>>> help(fh.tell)
Help on built-in function tell:

tell() method of _io.TextIOWrapper instance
Return current stream position.

>>> help(fh.seek)
Help on built-in function seek:

seek(cookie, whence=0, /) method of _io.TextIOWrapper instance
Change stream position.

Change the stream position to the given byte offset. The offset is
interpreted relative to the position indicated by whence.  Values
for whence are:

* 0 -- start of stream (the default); offset should be zero or positive
* 1 -- current stream position; offset may be negative
* 2 -- end of stream; offset is usually negative

Return the new absolute position.

[serhiy-storchaka]

Closed as a duplicate of newer issue #107801 which has more activity.

[erlend-aasland]

Closed as a duplicate of newer issue #107801 which has more activity.

+1