bug#55889: 29.0.50; Support mksh-specific function names in imenu

[Visuwesh <visuweshm@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 626 bytes --]

Tags: patch

mksh supports characters well beyond [:alnum:_] in its function names.
More specifically, syn.c:function_body says the following

	/*-
	 * Check for valid characters in name. POSIX and AT&T ksh93 say
	 * only allow [a-zA-Z_0-9] but this allows more as old pdkshs
	 * have allowed more; the following were never allowed:
	 *	NUL TAB NL SP " $ & ' ( ) ; < = > \ ` |
	 * C_QUOTE|C_SPC covers all but adds # * ? [ ]
	 */

However, it seems like executing a function with a forward-slash (/)
character in it is impossible as well.

Attached patch adds a mksh-specific entry to sh-imenu-generic-expression
to do that.


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0001-Support-mksh-specific-function-names-in-imenu.patch --]
[-- Type: text/x-diff, Size: 1609 bytes --]

From 53139e53b75aa37cc808c1c8b3e3be367ae09fb3 Mon Sep 17 00:00:00 2001
From: Visuwesh <visuweshm@gmail.com>
Date: Fri, 10 Jun 2022 20:01:03 +0530
Subject: [PATCH] Support mksh-specific function names in imenu

* lisp/progmodes/sh-script.el (sh-imenu-generic-expression): Add
mksh-specific function names to imenu-generic-expression.
---
 lisp/progmodes/sh-script.el | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/lisp/progmodes/sh-script.el b/lisp/progmodes/sh-script.el
index 4d2554c087..844fb690a5 100644
--- a/lisp/progmodes/sh-script.el
+++ b/lisp/progmodes/sh-script.el
@@ -286,7 +286,7 @@ sh-shell-arg
   :group 'sh-script)
 
 (defcustom sh-imenu-generic-expression
-  '((sh
+  `((sh
      . ((nil
 	 ;; function FOO
 	 ;; function FOO()
@@ -295,8 +295,21 @@ sh-imenu-generic-expression
 	;; FOO()
 	(nil
 	 "^\\s-*\\([[:alpha:]_][[:alnum:]_]*\\)\\s-*()"
-	 1)
-	)))
+	 1)))
+    (mksh
+     . ((nil
+         ;; function FOO
+         ;; function FOO()
+         ,(rx bol (* (syntax whitespace)) "function" (+ (syntax whitespace))
+              (group (1+ (not (any "\0\t\n \"$&'();<=>\\`|#*?[]/"))))
+              (* (syntax whitespace)) (? "()"))
+         1)
+        (nil
+         ;; FOO()
+         ,(rx bol (* (syntax whitespace))
+              (group (1+ (not (any "\0\t\n \"$&'();<=>\\`|#*?[]/"))))
+             (* (syntax whitespace)) "()")
+         1))))
   "Alist of regular expressions for recognizing shell function definitions.
 See `sh-feature' and `imenu-generic-expression'."
   :type '(alist :key-type (symbol :tag "Shell")
-- 
2.35.1