[Emacs-diffs] scratch/fix-33794-extend-electric-layout-mode 41a9132: Extend electric-layout-mode to handle more complex layouts

[João Távora]

branch: scratch/fix-33794-extend-electric-layout-mode
commit 41a913210d6e6dd720aa13e41ed8deb4b977ff37
Author: João Távora <address@hidden>
Commit: João Távora <address@hidden>

    Extend electric-layout-mode to handle more complex layouts
    
    Also, have it play nice with electric-pair-mode.
    
    Multiple matching entries in `electric-layout-rules' are executed in
    order of appearance.  When inserting a newline in the 'after-stay
    rule, ensure electric-pair-open-newline-between-pairs is nil.
    
    Arguably the logic behind electric-pair-open-newline-between-pairs
    should be moved to electric-layout-mode, but the current rule-matching
    engine doesn't allow for it.  The current solution seems to be good
    enough for the situations reported in bug#33794.
    
    * lisp/electric.el (electric-layout-rules): Adjust docstring.
    (electric-layout-post-self-insert-function): Loop through rules.  Bind
    electric-pair-open-newline-between-pairs to nil when handling
    after-stay.
---
 lisp/electric.el | 63 ++++++++++++++++++++++++++++++--------------------------
 1 file changed, 34 insertions(+), 29 deletions(-)

diff --git a/lisp/electric.el b/lisp/electric.el
index 6dbf46b8..9567772 100644
--- a/lisp/electric.el
+++ b/lisp/electric.el
@@ -370,38 +370,43 @@ function of no arguments that returns one of those 
symbols.
 
 The symbols specify where in relation to CHAR the newline
 character(s) should be inserted. `after-stay' means insert a
-newline after CHAR but stay in the same place.")
+newline after CHAR but stay in the same place.
+
+If multiple rules match, they are all executed in order of
+appearance.")
 
 (defun electric-layout-post-self-insert-function ()
-  (let* ((rule (cdr (assq last-command-event electric-layout-rules)))
-         pos)
-    (when (and rule
-               (setq pos (electric--after-char-pos))
-               ;; Not in a string or comment.
-               (not (nth 8 (save-excursion (syntax-ppss pos)))))
-      (let ((end (point-marker))
-            (sym (if (functionp rule) (funcall rule) rule)))
-        (set-marker-insertion-type end (not (eq sym 'after-stay)))
-        (goto-char pos)
-        (pcase sym
-          ;; FIXME: we used `newline' down here which called
-          ;; self-insert-command and ran post-self-insert-hook recursively.
-          ;; It happened to make electric-indent-mode work automatically with
-          ;; electric-layout-mode (at the cost of re-indenting lines
-          ;; multiple times), but I'm not sure it's what we want.
-          ;;
-          ;; FIXME: check eolp before inserting \n?
-          ('before (goto-char (1- pos)) (skip-chars-backward " \t")
-                   (unless (bolp) (insert "\n")))
-          ('after  (insert "\n"))
-          ('after-stay (save-excursion
-                         (let ((electric-layout-rules nil))
-                           (newline 1 t))))
-          ('around (save-excursion
-                     (goto-char (1- pos)) (skip-chars-backward " \t")
+  (let (pos)
+    (dolist (rule electric-layout-rules)
+      (when (and
+             (eq last-command-event (car rule))
+             (setq pos (electric--after-char-pos))
+             ;; Not in a string or comment.
+             (not (nth 8 (save-excursion (syntax-ppss pos)))))
+        (let ((end (point-marker))
+              (sym (if (functionp rule) (funcall rule) rule)))
+          (set-marker-insertion-type end (not (eq sym 'after-stay)))
+          (goto-char pos)
+          (pcase sym
+            ;; FIXME: we used `newline' down here which called
+            ;; self-insert-command and ran post-self-insert-hook recursively.
+            ;; It happened to make electric-indent-mode work automatically with
+            ;; electric-layout-mode (at the cost of re-indenting lines
+            ;; multiple times), but I'm not sure it's what we want.
+            ;;
+            ;; FIXME: check eolp before inserting \n?
+            ('before (goto-char (1- pos)) (skip-chars-backward " \t")
                      (unless (bolp) (insert "\n")))
-                   (insert "\n")))      ; FIXME: check eolp before inserting 
\n?
-        (goto-char end)))))
+            ('after  (insert "\n"))
+            ('after-stay (save-excursion
+                           (let ((electric-layout-rules nil)
+                                 (electric-pair-open-newline-between-pairs 
nil))
+                             (newline 1 t))))
+            ('around (save-excursion
+                       (goto-char (1- pos)) (skip-chars-backward " \t")
+                       (unless (bolp) (insert "\n")))
+                     (insert "\n")))      ; FIXME: check eolp before inserting 
\n?
+          (goto-char end))))))
 
 (put 'electric-layout-post-self-insert-function 'priority  40)