From: Dmitry Gutov <dmitry@gutov.dev>
To: Eli Zaretskii <eliz@gnu.org>,
Arteen Abrishami <arteen@linux.ucla.edu>,
Yuan Fu <casouri@gmail.com>
Cc: 67417@debbugs.gnu.org
Subject: bug#67417: 29.1.50; c-ts-mode syntax issues with no brackets
Date: Fri, 24 Nov 2023 20:26:34 +0200 [thread overview]
Message-ID: <2ba91823-bf3c-4d5d-e556-1622135ab2fd@gutov.dev> (raw)
In-Reply-To: <83h6lbfwcu.fsf@gnu.org>
On 24/11/2023 09:23, Eli Zaretskii wrote:
>> Date: Thu, 23 Nov 2023 12:55:31 -0800
>> From: Arteen Abrishami via "Bug reports for GNU Emacs,
>> the Swiss army knife of text editors"<bug-gnu-emacs@gnu.org>
>>
>> This is specifically for the usage of `c-ts-mode` and is not a problem
>> in `c-mode`. Sometimes, when you type something like:
>>
>> else
>> break
>>
>> it won't indent the "break" until you type a semicolon. In this below
>> scenario, it does not indent the break at all, but `c-mode` does, and
>> switching from `c-mode` to `c-ts-mode` with correct indentation leaves
>> it fixed, but `c-ts-mode` cannot detect or fix it itself.
>>
>> You can put it into a `.c` buffer all by itself and see:
>>
>> ```
>> unsigned
>> heap_pop(struct heapq * heap)
>> {
>> if (heap->sz == 0)
>> return -1;
>>
>> unsigned ret_val = heap->vals[0];
>> heap->vals[0] = heap->vals[heap->len];
>> heap->len -= 1;
>> unsigned i = 0;
>> unsigned lc;
>>
>> while ((lc = HEAPQ_L_CHILD(i)) < heap->len)
>> {
>> unsigned rc = HEAPQ_R_CHILD(i);
>> /* no right child for our guy, special case */
>> if (rc == heap->len)
>> {
>> if (heap->vals[lc] < heap->vals[i])
>> SWAP(heap->vals[lc], heap->vals[i]);
>> break;
>> }
>>
>> if (heap->vals[lc] < heap->vals[i])
>> {
>> SWAP(heap->vals[lc], heap->vals[i]);
>> i = lc;
>> }
>> else if (heap->vals[rc] < heap->vals[i])
>> {
>> SWAP(heap->vals[rc], heap->vals[i]);
>> i = rc;
>> }
>> else
>> break;
>>
>> }
>> }
>> ```
>>
>> The very last break on the else without brackets around it will not indent.c
> Yuan, any comments?
>
> My personal take on this is that as long as typing the required
> semi-colons fixes the indentation, we are okay in these cases, but if
> we can do better (i.e. if the problem is not that tree-sitter returns
> a tree with an error node), we should fix this even without relying on
> the electric semi-colon.
>
> In the specific example above, it looks like tree-sitter does succeed
> in parsing and shows a valid tree:
>
> alternative:
> (else_clause else
> (break_statement break ;)))))
>
> So I wonder why we don't indent the "break;" part here.
In my testing, it indents fine when after "else" there is either:
* some char(s) followed by closing curly
* or (optionally) some char(s) followed by semicolon
When there is _no_ code between "else" and the closing curly, it already
indents fine in my testing (whether the semicolon is added or not).
Without either, the text after "else" isn't parsed as "alternative:" --
it's parsed as a sibling of the "else" node. And, most unfortunately,
when "else" is followed by a closing curly, it's just parsed as (ERROR
else), so simply pressing RET does not indent the empty line properly
even when one is working with electric-pair-mode enabled.
I'd personally consider the last one a more definite bug in the grammar,
but maybe there is some good reason for it. I haven't found anything
relevant in the bug tracker.
BTW, it seems like the latest C grammar changed how else without braces
is parsed, so "break" isn't reindented even with semicolon at the end.
next prev parent reply other threads:[~2023-11-24 18:26 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-23 20:55 bug#67417: 29.1.50; c-ts-mode syntax issues with no brackets Arteen Abrishami via Bug reports for GNU Emacs, the Swiss army knife of text editors
2023-11-24 7:23 ` Eli Zaretskii
2023-11-24 18:26 ` Dmitry Gutov [this message]
2023-11-27 1:47 ` Yuan Fu
2023-11-27 2:22 ` Dmitry Gutov
2023-11-28 6:55 ` Yuan Fu
2023-11-28 14:27 ` Eli Zaretskii
2023-11-28 15:31 ` Dmitry Gutov
2023-12-01 7:58 ` Yuan Fu
2023-12-09 8:27 ` Eli Zaretskii
2023-12-10 9:29 ` Yuan Fu
2023-12-11 0:29 ` Dmitry Gutov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=2ba91823-bf3c-4d5d-e556-1622135ab2fd@gutov.dev \
--to=dmitry@gutov.dev \
--cc=67417@debbugs.gnu.org \
--cc=arteen@linux.ucla.edu \
--cc=casouri@gmail.com \
--cc=eliz@gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this external index
https://git.savannah.gnu.org/cgit/emacs.git
https://git.savannah.gnu.org/cgit/emacs/org-mode.git
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.