Subject: bug#64283: closed (Re: bug#64283: 29.0.91; js-mode's mark-defun does not work correctly when functions have a comment on top)

From: [email-masked] (GNU bug Tracking System)
Date: Thu, 29 Jun 2023 05:41:02 +0000

Your bug report

#64283: 29.0.91; js-mode's mark-defun does not work correctly when functions have a comment on top

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
64283: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=64283
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#64283: 29.0.91; js-mode's mark-defun does not work correctly when functions have a comment on top
From: Eli Zaretskii <[email-masked]>
To: Yuan Fu <[email-masked]>
Cc: [email-masked], [email-masked], [email-masked]
Date: Thu, 29 Jun 2023 08:41:00 +0300
List-Id: <debbugs-submit.debbugs.gnu.org>

> From: Yuan Fu <[email-masked]>
> Date: Wed, 28 Jun 2023 13:11:43 -0700
> Cc: Daniel Martín <[email-masked]>,
>  Dmitry Gutov <[email-masked]>,
>  [email-masked]
> 
> 
> 
> > On Jun 27, 2023, at 4:01 AM, Eli Zaretskii <[email-masked]> wrote:
> > 
> >> From: Yuan Fu <[email-masked]>
> >> Date: Mon, 26 Jun 2023 18:42:41 -0700
> >> Cc: Eli Zaretskii <[email-masked]>,
> >> Dmitry Gutov <[email-masked]>,
> >> [email-masked]
> >> 
> >>> 
> >>> What I see is that, after 4489450f37deafb013b1f0fc00c89f0973fda14a,
> >>> defun movement may be subtly broken if beginning-of-defun-function does
> >>> not return non-nil when it found the beginning of a defun.  One of the
> >>> affected modes is js-mode, but who knows if there are more out there.
> >>> 
> >>> We could either revert 4489450f37deafb013b1f0fc00c89f0973fda14a, because
> >>> of the incompatibilities it may cause (Yuan, what is the bug it tries to
> >>> fix?), or maybe adjust js-mode so that it follows the documentation of
> >>> beginning-of-defun-function and returns non-nil when it found the
> >>> beginning of a defun.  I've attached a patch that follows this second
> >>> approach, with some unit tests.  It fixes the bug on my side.
> >>> 
> >>> <0001-Make-js-beginning-of-defun-return-non-nil-on-success.patch>
> >> 
> >> The original problem that I tried to solve is that sometimes end-of-defun-function was called when point isn’t at the beginning of a defun, contrary to what the documentation claims. 
> >> 
> >> I first find out about it when writing defun movement functions for tree-sitter, but if you revert the commit now tree-sitter defun functions wouldn’t break: they have change quite a bit since then and treesit-end-of-defun don’t need to be called at the beginning of the defun anymore.
> > 
> > Thanks.
> > 
> > Do you (or anyone else) see a problem with the alternative proposed by
> > Daniel?  If not, I'd prefer not to revert at this stage, but instead
> > to apply the simple fix Daniel suggested.
> 
> I don’t see any problem :-)

Thanks.  So I've now installed Daniel's patch on the released branch,
and I'm therefore closing this bug.

Subject: 29.0.91; js-mode's mark-defun does not work correctly when functions have a comment on top
From: Daniel Martín <[email-masked]>
To: [email-masked]
Date: Sun, 25 Jun 2023 15:05:45 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

This is a regression from Emacs 28.2.

emacs -Q
C-x b sample.js RET
M-x js-mode
Paste the following code:

function foo() {
  var value = 1;
}

/* Hello */
function bar() {
  var value = 1;
}

Place the point inside function bar.
C-M-h

Expected result:

Function bar is marked.

Actual result:

Comment "/* Hello */" is marked.

This is probably related to the following regression:

When point is between function foo and function bar, C-M-e moves point
to the _beginning_ of bar, not to the end of bar.

In GNU Emacs 29.0.91 (build 8, aarch64-apple-darwin21.6.0, NS
 appkit-2113.60 Version 12.6 (Build 21G115)) of 2023-06-07 built on
 Daniels-MacBook-Pro.local
Repository revision: bcc222251e1a750a11e365f2faa641cc56c1169d
Repository branch: emacs-29
Windowing system distributor 'Apple', version 10.3.2113
System Description:  macOS 12.6.7

Configured using:
 'configure 'CFLAGS=-O0 -g3 -fsanitize=address'
 CPPFLAGS=-I/opt/homebrew/opt/openjdk@11/include'

Configured features:
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SQLITE3 THREADS TOOLKIT_SCROLL_BARS WEBP ZLIB

Important settings:
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  locale-coding-system: utf-8-unix

Major mode: Shell

Minor modes in effect:
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  tooltip-mode: t
  global-eldoc-mode: t
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Load-path shadows:
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Memory information:
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