Kill process if it's still running before starting a new one

Changelog.org

@@ -1,3 +1,8 @@
+* Unreleased
+
+- Kill process if it's still running before starting a new one in the same
+  buffer.
+
 * 0.14
 
 - Respect buffer-local environments, for compatibility with ~envrc.el~

justl.el

@@ -64,7 +64,7 @@
 ;; buffer via `justl-recipe width`.  By default it has a value of 20.
 ;;
 ;; You can change the shell between `eshell' and `vterm' using the `justl-shell'
 ;; variable. Using vterm requires the `vterm' package to be installed.
 ;;
 
 ;;; Code:
@@ -119,7 +119,7 @@
 
 (defcustom justl-shell 'eshell
   "Shell to use when running recipes.
 Can be either Eshell or vterm. Using vterm requires the vterm package to
 be installed."
   :type '(choice (const eshell)
                  (const vterm)))
@@ -285,6 +285,21 @@
 (defun justl-recompile ()
   "Execute the same just target again."
   (interactive)
+  ;; This is copied and adapted from `compilation-start'.
+  (let ((comp-proc (get-buffer-process (current-buffer))))
+    (if comp-proc
+        (if (or (not (eq (process-status comp-proc) 'run))
+                (eq (process-query-on-exit-flag comp-proc) nil)
+                (yes-or-no-p "The last target is still running; kill it? "))
+            (condition-case ()
+                (progn
+                  (interrupt-process comp-proc)
+                  (sit-for 1)
+                  (delete-process comp-proc))
+              (error nil))
+          (error "Cannot have two processes in `%s' at once"
+                 (buffer-name)))))
+
   (justl--make-process justl--compile-command (list :buffer (buffer-name)
                                                     :process "just"
                                                     :directory (if justl-justfile
@@ -523,10 +538,10 @@
   (interactive)
   (unless (require 'vterm nil t)
     (user-error "Package `vterm' was not found!"))
   (let* ((recipe (justl--get-recipe-under-cursor))
          (vterm-buffer-name (format "justl - vterm - %s" (justl--recipe-name recipe)))
          (default-directory (f-dirname justl-justfile)))
     (vterm)
 
     (let* ((recipe-name (justl--recipe-name recipe))
            (recipe-args (justl--recipe-args recipe))
@@ -535,9 +550,9 @@
                             (append transient-args
                                     (list recipe-name)
                                     (mapcar 'justl--arg-default recipe-args)))))
       (vterm-insert (string-join args-list " ")))
     (unless no-send
       (vterm-send-return))))
 
 (defun justl-no-exec-vterm ()
   "Open vterm with the recipe but do not execute it."