Re: [PATCH 1/2] sequencer: truncate labels to accommodate loose refs

From: Junio C Hamano <gitster@pobox.com>
Date: Aug 16, 2023, 16:28 UTC
Message-ID: <xmqqcyzneyt2.fsf@gitster.g>
In-Reply-To: <42dd6b6f-4d33-724c-ab15-ba7bb5ead733@gmx.de>

Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

Show 8 quoted lines

> It is not a performance-critical code path, so I erred on the side of
> simplicity (although I have to admit that the post image of the diff is
> not exactly for the faint of heart).
>
> Could we maybe form the plan to keep in the back of our heads that we
> already have a UTF-8-truncating functionality in sequencer, and in case
> another user should turn up, implemnt that optimized function in
> `utf8.[ch]`?

Yup, that is a good idea. Even though this one only cares about the bytecount, we'd eventually benefit from two variants, truncate by bytecount and truncate by display width. Both variants should return an error when given a bytestring that does not make a valid UTF-8 sequence, and leave it to the caller to truncate at byte boundary as a fallback, which is trivial (the alternative would be to do the truncation by the callee, but then caller cannot tell if the returned result is a fallback result that the end user may need to be warned about or a known-valid UTF-8 substring if we go that route, so it would be suboptimal).

Thanks.