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Subject: Re: [PATCH v4] pretty-formats: add hard truncation, without ellipsis,
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From:   Philip Oakley <philipoakley@iee.email>
To:     Junio C Hamano <gitster@pobox.com>
Cc:     GitList <git@vger.kernel.org>, Taylor Blau <me@ttaylorr.com>,
        NSENGIYUMVA WILBERFORCE <nsengiyumvawilberforce@gmail.com>
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On 26/11/2022 14:32, Philip Oakley wrote:
> A careful read (and testing) of the existing 'mtrunc' does show a
> rounding error bug though. Its a confusion between the computed start
> and end points of the cut that loses one display column (the string
> displayed is short by one when the count is odd, IIUC).

I had confused myself.

My test case `git log --graph --format="%<(19,mtrunc)%d=2" -6` had a
2-char step in the graph that I confused with the effects between
repeated runs with the 'N' value adjusted by +1 and -1.

I then jumped to conclusions about the integer division in the mid
string position of the mtrunc case win the code.

Sorry for that.