[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
bug#22763: 25.1.50; Feature Request -- A faster method to obtain line nu
From: |
Eli Zaretskii |
Subject: |
bug#22763: 25.1.50; Feature Request -- A faster method to obtain line number at position. |
Date: |
Fri, 21 May 2021 08:46:45 +0300 |
> Date: Thu, 20 May 2021 20:40:31 +0000
> From: Ben Levy via "Bug reports for GNU Emacs,
> the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
>
> (with-temp-buffer
> (insert "foo\nbar\nbaz")
> (narrow-to-region 4 5)
> (message "%s" (line-number-at-pos 1 t)))
>
> On the latest master (ef7a6eec20), this errors with
>
> Args out of range: 1, 4, 5
>
> But on emacs-27.2, it prints "1".
This is the expected behavior: the POSITION argument must be in the
accessible portion of the buffer, like every position argument in
Emacs. A Lisp program which calls this function like above has a bug
that needs to be fixed.
This is not a bug.
> >From what I can tell, this is because the lisp version of line-number-at-pos
> allowed the argument to be outside the visible range, and it widened before
> counting lines to allow this.
Right, the Lisp implementation was incorrect, and failed to do the
test before widening.