Use compilation-filter as subprocess filter

justl.el

@@ -24,7 +24,7 @@
 ;; Keywords: just justfile tools processes
 ;; URL: https://github.com/psibi/justl.el
 ;; License: GNU General Public License >= 3
-;; Package-Requires: ((transient "0.1.0") (emacs "25.3") (xterm-color "2.0") (s "1.2.0") (f "0.20.0"))
+;; Package-Requires: ((transient "0.1.0") (emacs "25.3") (s "1.2.0") (f "0.20.0"))
 
 ;;; Commentary:
 
@@ -60,12 +60,23 @@
 ;;
 ;; You can also control the width of the RECIPE column in the justl
 ;; buffer via `justl-recipe width`.  By default it has a value of 20.
+;;
+;; You can enable coloring of the output by adding proper hook to
+;; `compilation-filter-hook`. For Emacs older than 28.1 you need to
+;; define it like this:
+;; (require 'ansi-color)
+;; (defun my-color-compilation-filter ()
+;;   (let ((inhibit-read-only t))
+;;     (ansi-color-apply-on-region compilation-filter-start (point))))
+;; (add-hook 'compilation-filter-hook 'my-color-compilation-filter)
+;; For Emacs 28.1 or newer it's as simple as:
+;; (require 'ansi-color)
+;; (add-hook 'compilation-filter-hook 'ansi-color-compilation-filter)
 
 ;;; Code:
 
 (require 'transient)
 (require 'cl-lib)
-(require 'xterm-color)
 (require 'eshell)
 (require 'esh-mode)
 (require 's)
@@ -283,21 +294,6 @@ CMD is the just command as a list."
                  process-name
                  err))))))
 
-(defun justl--xterm-color-filter (proc string)
-  "Filter function for PROC handling colors.
-
-STRING is the data returned by the PROC"
-  (when (buffer-live-p (process-buffer proc))
-    (with-current-buffer (process-buffer proc)
-      (let ((inhibit-read-only t)
-            (moving (= (point) (process-mark proc))))
-        (save-excursion
-          ;; Insert the text, advancing the process marker.
-          (goto-char (process-mark proc))
-          (insert (xterm-color-filter string))
-          (set-marker (process-mark proc) (point)))
-        (if moving (goto-char (process-mark proc)))))))
-
 (defun justl-compilation-setup-buffer (buf dir mode &optional no-mode-line)
   "Setup the compilation buffer for just-compile-mode.
 
@@ -349,7 +345,7 @@ ARGS is a plist that affects how the process is run.
 
         (setq-local justl--justfile (justl--justfile-from-arg (elt command 1)))
         (run-hook-with-args 'compilation-start-hook process)
-        (set-process-filter process 'justl--xterm-color-filter)
+        (set-process-filter process 'compilation-filter)
         (set-process-sentinel process sentinel)
         (set-process-coding-system process 'utf-8-emacs-unix 'utf-8-emacs-unix)
         (pop-to-buffer buf)))))
@@ -430,7 +426,7 @@ ARGS is a ist of arguments."
     (justl--log-command process-name cmd)
     (make-process :name process-name
                   :buffer buffer-name
-                  :filter 'justl--xterm-color-filter
+                  :filter 'compilation-filter
                   :sentinel #'justl--sentinel
                   :file-handler t
                   :stderr nil