>From fab65a75b71d2800e5d549f01a746b3be98a0444 Mon Sep 17 00:00:00 2001
From: Barna Zsombor <address@hidden>
Date: Tue, 7 Apr 2020 16:46:51 +0200
Subject: [PATCH] Add ERC support for italic control characters

ERC lacked support for the ']' control character, it didn't
display italic text as italic.

- Added erc-italic-face

- Updated the regexes

- Added cond branches and extended the let expressions
---
 lisp/erc/erc-goodies.el | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/lisp/erc/erc-goodies.el b/lisp/erc/erc-goodies.el
index 94d5de280c..0e9b9384b3 100644
--- a/lisp/erc/erc-goodies.el
+++ b/lisp/erc/erc-goodies.el
@@ -241,6 +241,10 @@ erc-underline-face
   "ERC underline face."
   :group 'erc-faces)
 
+(defface erc-italic-face '((t :slant italic))
+  "ERC italic face."
+  :group 'erc-faces)
+
 (defface fg:erc-color-face0 '((t :foreground "White"))
   "ERC face."
   :group 'erc-faces)
@@ -385,6 +389,7 @@ erc-controls-interpret
               (let ((boldp nil)
                     (inversep nil)
                     (underlinep nil)
+                    (italicp nil)
                     (fg nil)
                     (bg nil))
                 (while (string-match erc-controls-highlight-regexp s)
@@ -405,6 +410,8 @@ erc-controls-interpret
                            (setq inversep (not inversep)))
                           ((string= control "\C-_")
                            (setq underlinep (not underlinep)))
+                          ((string= control "\C-]")
+                           (setq italicp (not italicp)))
                           ((string= control "\C-c")
                            (setq fg nil
                                  bg nil))
@@ -419,7 +426,7 @@ erc-controls-interpret
                                  bg nil))
                           (t nil))
                     (erc-controls-propertize
-                     start end boldp inversep underlinep fg bg s)))
+                     start end boldp inversep underlinep italicp fg bg s)))
                 s))
              (t s)))))
 
@@ -432,11 +439,11 @@ erc-controls-strip
       s)))
 
 (defvar erc-controls-remove-regexp
-  "\C-b\\|\C-_\\|\C-v\\|\C-g\\|\C-o\\|\C-c[0-9]?[0-9]?\\(,[0-9][0-9]?\\)?"
+  "\C-b\\|\C-_\\|\C-]\\|\C-v\\|\C-g\\|\C-o\\|\C-c[0-9]?[0-9]?\\(,[0-9][0-9]?\\)?"
   "Regular expression which matches control characters to remove.")
 
 (defvar erc-controls-highlight-regexp
-  (concat "\\(\C-b\\|\C-v\\|\C-_\\|\C-g\\|\C-o\\|"
+  (concat "\\(\C-b\\|\C-v\\|\C-_\\|\C-]\\|\C-g\\|\C-o\\|"
           "\C-c\\([0-9][0-9]?\\)?\\(,\\([0-9][0-9]?\\)\\)?\\)"
           "\\([^\C-b\C-v\C-_\C-c\C-g\C-o\n]*\\)")
   "Regular expression which matches control chars and the text to highlight.")
@@ -453,6 +460,7 @@ erc-controls-highlight
          (let ((boldp nil)
                (inversep nil)
                (underlinep nil)
+               (italicp nil)
                (fg nil)
                (bg nil))
            (while (re-search-forward erc-controls-highlight-regexp nil t)
@@ -471,6 +479,8 @@ erc-controls-highlight
                       (setq inversep (not inversep)))
                      ((string= control "\C-_")
                       (setq underlinep (not underlinep)))
+                     ((string= control "\C-]")
+                      (setq italicp (not italicp)))
                      ((string= control "\C-c")
                       (setq fg nil
                             bg nil))
@@ -481,14 +491,15 @@ erc-controls-highlight
                       (setq boldp nil
                             inversep nil
                             underlinep nil
+                            italicp nil
                             fg nil
                             bg nil))
                      (t nil))
                (erc-controls-propertize start end
-                                        boldp inversep underlinep fg bg)))))
+                                        boldp inversep underlinep italicp fg bg)))))
         (t nil)))
 
-(defun erc-controls-propertize (from to boldp inversep underlinep fg bg
+(defun erc-controls-propertize (from to boldp inversep underlinep italicp fg bg
                                      &optional str)
   "Prepend properties from IRC control characters between FROM and TO.
 If optional argument STR is provided, apply to STR, otherwise prepend properties
@@ -506,6 +517,9 @@ erc-controls-propertize
            (if underlinep
                '(erc-underline-face)
              nil)
+           (if italicp
+               '(erc-italic-face)
+             nil)
            (if fg
                (list (erc-get-fg-color-face fg))
              nil)
-- 
2.26.0