bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Unknown]

The new smiley-style called emoji takes advantage of the harfbuzz glyph
rendering to represent smileys as colorful unicode emoji rather than
images.

* lisp/gnus/smiley.el (smiley-style): Add emoji
tag. (smiley-emoji-regexp-alist): New defcustom. (smiley-update-cache,
smiley-region): Support emoji (non-image) replacement.
---

How about an option to use emoji for smileys in Gnus?

 lisp/gnus/smiley.el | 76 +++++++++++++++++++++++++++++++++------------
 1 file changed, 56 insertions(+), 20 deletions(-)

diff --git a/lisp/gnus/smiley.el b/lisp/gnus/smiley.el
index 5504a52078..7d6efacfe0 100644
--- a/lisp/gnus/smiley.el
+++ b/lisp/gnus/smiley.el
@@ -44,6 +44,7 @@
 ;; cry               😢
 ;; dead              😵
 ;; grin              😀
+;; halo              😇
 
 ;;; Code:
 
@@ -64,7 +65,8 @@ smiley-style
   "Smiley style."
   :type '(choice (const :tag "small, 3 colors" low-color)  ;; 13x14
 		 (const :tag "medium, ~10 colors" medium)  ;; 16x16
-		 (const :tag "dull, grayscale" grayscale)) ;; 14x14
+		 (const :tag "dull, grayscale" grayscale)  ;; 14x14
+                 (const :tag "emoji, full color" emoji))
   :set (lambda (symbol value)
 	 (set-default symbol value)
 	 (setq smiley-data-directory (smiley-directory))
@@ -96,6 +98,35 @@ smiley-data-directory
   :type 'directory
   :group 'smiley)
 
+(defcustom smiley-emoji-regexp-alist
+  '(("\\(😉\\)\\W" 1 "😉")
+    ("[^;]\\(😉\\)\\W" 1 "😉")
+    ("\\(😬\\)\\W" 1 "😬")
+    ("\\(🥴\\)\\W" 1 "🥴")
+    ("\\(😐\\)\\W" 1 "😐")
+    ("\\(:-[/\\]\\)\\W" 1 "😕")
+    ("\\(😠\\)\\W" 1 "😠")
+    ("\\(😵\\)\\W" 1 "😵") ; 💀
+    ("\\(😦\\)\\W" 1 "😦")
+    ("\\(😈\\)\\W" 1 "😈")
+    ("\\(😢\\)\\W" 1 "😢")
+    ("\\(😀\\)\\W" 1 "😀")
+    ("\\(😇\\)\\W" 1 "😇")
+    ;; "smile" must be come after "evil"
+    ("\\(\\^?:-?)\\)\\W" 1 "🙂"))
+  "A list of regexps to map smilies to emoji.
+The elements are (REGEXP MATCH EMOJI), where MATCH is the submatch in
+regexp to replace with EMOJI."
+  :version "28.1"
+  :type '(repeat (list regexp
+		       (integer :tag "Regexp match number")
+		       (string :tag "Emoji")))
+  :set (lambda (symbol value)
+	 (set-default symbol value)
+	 (smiley-update-cache))
+  :initialize 'custom-initialize-default
+  :group 'smiley)
+
 ;; The XEmacs version has a baroque, if not rococo, set of these.
 (defcustom smiley-regexp-alist
   '(("\\(😉\\)\\W" 1 "blink")
@@ -142,23 +173,25 @@ smiley-cached-regexp-alist
 
 (defun smiley-update-cache ()
   (setq smiley-cached-regexp-alist nil)
-  (dolist (elt (if (symbolp smiley-regexp-alist)
-		   (symbol-value smiley-regexp-alist)
-		 smiley-regexp-alist))
-    (let ((types gnus-smiley-file-types)
-	  file type)
-      (while (and (not file)
-		  (setq type (pop types)))
-	(unless (file-exists-p
-		 (setq file (expand-file-name (concat (nth 2 elt) "." type)
-					      smiley-data-directory)))
-	  (setq file nil)))
-      (when type
-	(let ((image (gnus-create-image file (intern type) nil
-					:ascent 'center)))
-	  (when image
-	    (push (list (car elt) (cadr elt) image)
-		  smiley-cached-regexp-alist)))))))
+  (if (eq smiley-style 'emoji)
+      (setq smiley-cached-regexp-alist smiley-emoji-regexp-alist)
+    (dolist (elt (if (symbolp smiley-regexp-alist)
+		     (symbol-value smiley-regexp-alist)
+		   smiley-regexp-alist))
+      (let ((types gnus-smiley-file-types)
+	    file type)
+        (while (and (not file)
+		    (setq type (pop types)))
+	  (unless (file-exists-p
+		   (setq file (expand-file-name (concat (nth 2 elt) "." type)
+					        smiley-data-directory)))
+	    (setq file nil)))
+        (when type
+	  (let ((image (gnus-create-image file (intern type) nil
+					  :ascent 'center)))
+	    (when image
+	      (push (list (car elt) (cadr elt) image)
+		    smiley-cached-regexp-alist))))))))
 
 ;; Not implemented:
 ;; (defvar smiley-mouse-map
@@ -190,8 +223,11 @@ smiley-region
 	    (when image
 	      (push image images)
 	      (gnus-add-wash-type 'smiley)
-	      (gnus-add-image 'smiley image)
-	      (gnus-put-image image string 'smiley))))
+              (if (symbolp image)
+                  (progn
+	            (gnus-add-image 'smiley image)
+	            (gnus-put-image image string 'smiley))
+                (insert image)))))
 	images))))
 
 ;;;###autoload
-- 

2.28.0

-- 
 "I'm sorry I sound calm. I assure you that                 Adam Sjøgren
  I am hysterical."                                    asjo@koldfront.dk


In GNU Emacs 28.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.23, cairo version 1.16.0)
 of 2020-10-03 built on tullinup
Repository revision: 98728d576cf4db789a3f7e1ff01a4edcac985485
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12009000
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bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Eli Zaretskii]

> Date: Fri, 09 Oct 2020 21:35:06 +0200
> From: Adam Sjøgren via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> The new smiley-style called emoji takes advantage of the harfbuzz glyph
> rendering to represent smileys as colorful unicode emoji rather than
> images.

It doesn't actually test for HarfBuzz availability, or did I miss
that?

Thanks.

bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Unknown]

Eli writes:

>> The new smiley-style called emoji takes advantage of the harfbuzz glyph
>> rendering to represent smileys as colorful unicode emoji rather than
>> images.
>
> It doesn't actually test for HarfBuzz availability, or did I miss
> that?

It doesn't - you have to choose the style yourself, by customizing the
smiley-style variable.

The patch does not change the default value of smiley-style, it just
adds yet another option for the user to choose.

I could have presented it better: what I was trying to say is that now
that Emacs can present unicode emoji in colors (which I understand is
due to harfbuzz), this option can be a useful alternative to
representing smileys with color images, to achieve the desired effect.


  Best regards,

    Adam

-- 
 "SUVs are gross because they're the solution to a          Adam Sjøgren
  gross problem. (How to make minivans look more       asjo@koldfront.dk
  masculine.)"

bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Eli Zaretskii]

> From: Adam Sjøgren <asjo@koldfront.dk>
> Cc: 43889@debbugs.gnu.org
> Date: Sat, 10 Oct 2020 13:12:32 +0200
> 
> Eli writes:
> 
> >> The new smiley-style called emoji takes advantage of the harfbuzz glyph
> >> rendering to represent smileys as colorful unicode emoji rather than
> >> images.
> >
> > It doesn't actually test for HarfBuzz availability, or did I miss
> > that?
> 
> It doesn't - you have to choose the style yourself, by customizing the
> smiley-style variable.

How about adding that: the font-backend frame parameter should tell
you if HarfBuzz is available.

> The patch does not change the default value of smiley-style, it just
> adds yet another option for the user to choose.

My point was to help the user in this matter, by using this only if
available.

> I could have presented it better: what I was trying to say is that now
> that Emacs can present unicode emoji in colors (which I understand is
> due to harfbuzz), this option can be a useful alternative to
> representing smileys with color images, to achieve the desired effect.

Perhaps when HarfBuzz is being used, it should be the default?  I
don't use Gnus, but maybe such a new default will make sense to Gnus
users?

bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Unknown]

Eli writes:

>>> It doesn't actually test for HarfBuzz availability, or did I miss
>>> that?
>> 
>> It doesn't - you have to choose the style yourself, by customizing the
>> smiley-style variable.
>
> How about adding that: the font-backend frame parameter should tell
> you if HarfBuzz is available.

Do you mean removing the option if HarfBuzz isn't available?

As far as I understand it, emoji can be displayed without, they just
won't have color? Which might be something that users without HarfBuzz
would like to be able to choose.

(Having color emoji is just my motivation to make the patch.)

> Perhaps when HarfBuzz is being used, it should be the default?  I
> don't use Gnus, but maybe such a new default will make sense to Gnus
> users?

I think changing the default would be annoying to users, but I don't
have any evidence in either direction. Maybe some users would consider
it "modern" to change it.


  Best regards,

    Adam

-- 
 "Do not feed the oysters under the clouds"                 Adam Sjøgren
                                                       asjo@koldfront.dk

bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Lars Ingebrigtsen]

Adam Sjøgren <asjo@koldfront.dk> writes:

> The new smiley-style called emoji takes advantage of the harfbuzz glyph
> rendering to represent smileys as colorful unicode emoji rather than
> images.
>
> * lisp/gnus/smiley.el (smiley-style): Add emoji
> tag. (smiley-emoji-regexp-alist): New defcustom. (smiley-update-cache,
> smiley-region): Support emoji (non-image) replacement.

Sounds good to me, but I think the patch was destroyed somewhere along
the way?  At least it doesn't apply to me, and...  it doesn't quite
make sense, either because it's all

+    ("\\(😬\\)\\W" 1 "😬")

If we see a 😬, then transform it to 😬?  Has something pre-transformed
smilies into Unicode along the way?  Very mysterious.

So could you resend the patch as an attachment?

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Unknown]

Lars writes:

> I think the patch was destroyed somewhere along the way?

I couldn't make M-x report-emacs-bug work for me, it kept spawning
browsers, and, yes, something seems to have gone wrong.


  Anyway,

   Adam

-- 
 "Set out on a laughless day                                Adam Sjøgren
  Like a troupe of clowns"                             asjo@koldfront.dk

bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Lars Ingebrigtsen]

Adam Sjøgren <asjo@koldfront.dk> writes:

> I couldn't make M-x report-emacs-bug work for me, it kept spawning
> browsers, and, yes, something seems to have gone wrong.

But are you going to re-send the patch as an attachment?  :-)

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Robert Pluim]

(*sigh*, either gmane or bug-gnu-emacs or Gnus mangled the Reply-To
header here)

>>>>> On Sat, 10 Oct 2020 13:55:54 +0200, Unknown <unknown@unknown.invalid> said:

    Adam> Eli writes:
    >>>> It doesn't actually test for HarfBuzz availability, or did I miss
    >>>> that?
    >>> 
    >>> It doesn't - you have to choose the style yourself, by customizing the
    >>> smiley-style variable.
    >> 
    >> How about adding that: the font-backend frame parameter should tell
    >> you if HarfBuzz is available.

By looking for the substring 'hb' in it? Could we add something a
little less icky, along the lines of 'libxml-available-p'?

    Adam> Do you mean removing the option if HarfBuzz isn't available?

I donʼt think this is dependent on Harfbuzz, etc/NEWS.27:

    ** Multicolor fonts such as "Noto Color Emoji" can be displayed on
    Emacs configured with Cairo drawing and linked with cairo >= 1.16.0.

(and on macOS, if explicitly requested)

    Adam> As far as I understand it, emoji can be displayed without, they just
    Adam> won't have color? Which might be something that users without HarfBuzz
    Adam> would like to be able to choose.

    Adam> (Having color emoji is just my motivation to make the patch.)

They'd be displayed with whatever font Emacs found for them.

    >> Perhaps when HarfBuzz is being used, it should be the default?  I
    >> don't use Gnus, but maybe such a new default will make sense to Gnus
    >> users?


    Adam> I think changing the default would be annoying to users, but I don't
    Adam> have any evidence in either direction. Maybe some users would consider
    Adam> it "modern" to change it.

As a Gnus user I wouldnʼt object to it being the default, as long as
there was a reasonable fallback for when those characters cannot be
displayed.

Robert
-- 

bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Eli Zaretskii]

> From: Robert Pluim <rpluim@gmail.com>
> Cc: Eli Zaretskii <eliz@gnu.org>,  43889@debbugs.gnu.org
> Date: Mon, 12 Oct 2020 11:03:53 +0200
> 
>     >> How about adding that: the font-backend frame parameter should tell
>     >> you if HarfBuzz is available.
> 
> By looking for the substring 'hb' in it?

Not necessarily.  The set of HarfBuzz-based font backends is very
small, so we could just have a list and test against it.

> Could we add something a little less icky, along the lines of
> 'libxml-available-p'?

We could, but it wouldn't tell us whether HarfBuzz is actually being
used (as opposed to being the fallback).

But this looks like a moot point, given what you write below:

>     Adam> Do you mean removing the option if HarfBuzz isn't available?
> 
> I donʼt think this is dependent on Harfbuzz, etc/NEWS.27:
> 
>     ** Multicolor fonts such as "Noto Color Emoji" can be displayed on
>     Emacs configured with Cairo drawing and linked with cairo >= 1.16.0.
> 
> (and on macOS, if explicitly requested)
> 
>     Adam> As far as I understand it, emoji can be displayed without, they just
>     Adam> won't have color? Which might be something that users without HarfBuzz
>     Adam> would like to be able to choose.
> 
>     Adam> (Having color emoji is just my motivation to make the patch.)
> 
> They'd be displayed with whatever font Emacs found for them.
> 
>     >> Perhaps when HarfBuzz is being used, it should be the default?  I
>     >> don't use Gnus, but maybe such a new default will make sense to Gnus
>     >> users?
> 
> 
>     Adam> I think changing the default would be annoying to users, but I don't
>     Adam> have any evidence in either direction. Maybe some users would consider
>     Adam> it "modern" to change it.
> 
> As a Gnus user I wouldnʼt object to it being the default, as long as
> there was a reasonable fallback for when those characters cannot be
> displayed.

bug#43889: 28.0.50; [PATCH] Add new smiley-style emoji to Gnus

[Lars Ingebrigtsen]

Adam Sjøgren <asjo@koldfront.dk> writes:

> Here's the unmangled patch:

Thanks; I've now pushed it to Emacs 28.

But I see that it really rewrites the buffer instead of using display
properties, so I changed that (so that the transformation can be
reversed, and doesn't propagate to saved files).