[Emacs-diffs] master ef0fc0b: New edebug-spec, nested-backquote-form. This fixes bug #31090

[Alan Mackenzie]

branch: master
commit ef0fc0bed1c97a1c803fa83bee438ca9cfd238b0
Author: Alan Mackenzie <address@hidden>
Commit: Alan Mackenzie <address@hidden>

    New edebug-spec, nested-backquote-form.  This fixes bug #31090
    
    * lisp/emacs-lisp/edebug.el: (nested-backquote-form): a new edebug-spec 
which
    handles nested backquote structures without a , or ,@ "between" the outer 
and
    inner backquotes.
    (backquote-form): Use nested-backquote-form.
---
 lisp/emacs-lisp/edebug.el | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/lisp/emacs-lisp/edebug.el b/lisp/emacs-lisp/edebug.el
index c898da3..7170269 100644
--- a/lisp/emacs-lisp/edebug.el
+++ b/lisp/emacs-lisp/edebug.el
@@ -2165,6 +2165,9 @@ into `edebug--cl-macrolet-defs' which is checked in 
`edebug-list-form-args'."
 ;; but only at the top level inside unquotes.
 (def-edebug-spec backquote-form
   (&or
+   ;; Disallow instrumentation of , and ,@ inside a nested backquote, since
+   ;; these are likely to be forms generated by a macro being debugged.
+   ("`" nested-backquote-form)
    ([&or "," ",@"] &or ("quote" backquote-form) form)
    ;; The simple version:
    ;;   (backquote-form &rest backquote-form)
@@ -2180,6 +2183,16 @@ into `edebug--cl-macrolet-defs' which is checked in 
`edebug-list-form-args'."
    (vector &rest backquote-form)
    sexp))
 
+(def-edebug-spec nested-backquote-form
+  (&or
+   ;; Allow instrumentation of any , or ,@ contained within the (\, ...) or
+   ;; (\,@ ...) matched on the next line.
+   ([&or "," ",@"] backquote-form)
+   (nested-backquote-form [&rest [&not "," ",@"] nested-backquote-form]
+                          . [&or nil nested-backquote-form])
+   (vector &rest nested-backquote-form)
+   sexp))
+
 ;; Special version of backquote that instruments backquoted forms
 ;; destined to be evaluated, usually as the result of a
 ;; macroexpansion.  Backquoted code can only have unquotes (, and ,@)