bug#41868: [PATCH] Add project-clean-up command

[Philip K.]

Dmitry Gutov <dgutov@yandex.ru> writes:

> On 15.06.2020 21:18, Philip K. wrote:
>
>  > +(defcustom project-spare-buffers-regexps
>  > +  '("\\*Help\\*")
>
> Perhaps also call this project-buffer-spare-conditions? Or something 
> like that. Point is, no tie the name to regexps, for easy extension into 
> having functions in that list as well.

Renamed it an implemented support for predicates too.

>  > +  "List of regular expressions to be ignored by `project-clean-up'."
>
> Forgotten reference to the previous name.

There was also some superfluous code from an attempt to reimplement
yes-or-no-p with a third option I removed. Also fixed an inconsistency,
where the prompt would tell the user that more buffers would be killed
that would actually be, depending on the value of
project-buffer-spare-conditions.

(naively) Hoping everything it ok this time.

-- 
        Philip K.

>From 20ab9f1f8fe603e8ea8fe24a7d0e1fdd60be08bb Mon Sep 17 00:00:00 2001
From: Philip K <philip@warpmail.net>
Date: Fri, 12 Jun 2020 23:37:51 +0200
Subject: [PATCH] Add project-kill-buffers command

---
 lisp/progmodes/project.el | 41 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/lisp/progmodes/project.el b/lisp/progmodes/project.el
index f3df44fa7b..50155e55dd 100644
--- a/lisp/progmodes/project.el
+++ b/lisp/progmodes/project.el
@@ -744,6 +744,47 @@ project-compile
          (default-directory (project-root pr)))
     (compile command comint)))
 
+(defcustom project-spare-buffers-conditions
+  '("\\*Help\\*")
+  "List of conditions to be ignored by `project-kill-buffers'.
+If a condition is a string, it will be interpreted as a regular
+expression. If the buffer name matches the regular expresion, the
+buffer will not be killed.  If a contition is a function, it will
+be called with the buffer object. If it returns a non-nil value,
+the buffer will not be killed."
+  :type '(repeat (choice regexp function))
+  :version "28.1")
+
+(defun project--buffer-list (pr)
+  "Return a list of all buffers in project PR."
+  (let ((root (project-root pr)) bufs)
+    (dolist (buf (buffer-list))
+      (let ((filename (or (buffer-file-name buf)
+                          (buffer-local-value 'default-directory buf))))
+        (when (and filename (file-in-directory-p filename root))
+          (push buf bufs))))
+    (nreverse bufs)))
+
+;;;###autoload
+(defun project-kill-buffers ()
+  "Kill all live buffers of a project.
+Certain buffers may be ignored, depending on the value of
+`project-spare-buffers-conditions'."
+  (interactive)
+  (let* ((pr (project-current t)) bufs)
+    (dolist (buf (project--buffer-list pr))
+      (unless (seq-some
+               (lambda (c)
+                 (cond ((stringp c)
+                        (string-match-p c (buffer-name buf)))
+                       ((functionp c)
+                        (funcall c buf))))
+               project-spare-buffers-conditions)
+        (push buf bufs)))
+    (when (yes-or-no-p (format "Kill %d buffers in %s? "
+                               (length bufs) (project-root pr)))
+      (mapc #'kill-buffer bufs))))
+
 
 ;;; Project list
 
-- 
2.20.1