New style {format} strings in logging calls

[pradyunsg]

I do wonder if there's some way to make the format strings for logging calls to use the new-style formatting.

Originally posted by @pradyunsg in #6973 (comment)

It'd be nice to be able to switch over TBH.

[pradyunsg]

Relabeled, since I think everyone would agree that switching to a single format would be best. :)

[uranusjr]

The logging module can handle brace formatting, but IIRC the conversion needs to be done in one shot, not incrementally.

[McSinyx]

Hi there, this seems to have been done in GH-7826, then reverted because of regression (probably due to some minor mistake have to do with implicit use of kwargs, e.g. locals). May I take over this since it's not technically a too difficult task?

[pradyunsg]

Looking at the Python 2 support situation for this change, I think we should wait until Python 2 support is dropped to do this.

[McSinyx]

Oops I saw the comment in the PR and reply to it first. There are 2 things needed to be changed:

• The formatting of messages passed to logger.*, i.e. positional arguments, which can be done now IMHO
• The formatting of the formatted messages, i.e. the %(field)s -> {field} kind of thing, which must be deferred since it's hardcoded as % in Python 2.

[pradyunsg]

Closing this out. I don’t think we’d be able to do this in the near future. If someone thinks it’s possible, let’s open a new issue instead.