refactor(media): extract the playback sentinel as a named builder

- cj/media--play-sentinel returns the per-process closure.
- Three new tests pin the reap-on-exit behavior.

2 files changed, 48 insertions, 10 deletions

diff --git a/modules/media-utils.el b/modules/media-utils.el
index e3f4022f..99b5dc37 100644
--- a/modules/media-utils.el
+++ b/modules/media-utils.el
@@ -162,6 +162,19 @@ nothing."
 				(error "yt-dlp resolved no stream URL for %s" url))))
 	  (delete-file err-file))))
 
+(defun cj/media--play-sentinel (url-display)
+  "A process sentinel reporting playback of URL-DISPLAY.
+Messages success or failure and reaps the process buffer once the
+player finishes or exits."
+  (lambda (proc event)
+	(cond
+	 ((string-match-p "finished" event)
+	  (message "✓ Finished playing: %s" url-display))
+	 ((string-match-p "exited abnormally" event)
+	  (message "✗ Playback failed: %s" url-display)))
+	(when (string-match-p "finished\\|exited" event)
+	  (kill-buffer (process-buffer proc)))))
+
 (defun cj/media-play-it (url)
   "Play the URL with the configured media player in an async process.
 A player flagged :needs-stream-url gets the URL resolved first via a
@@ -193,16 +206,7 @@ with a plain argv list -- no shell anywhere in the pipeline."
 	  (cj/log-silently "DEBUG: Executing: %s" (string-join argv " "))
 
 	  (let ((process (apply #'start-process player-name buffer-name argv)))
-		(set-process-sentinel
-		 process
-		 (lambda (proc event)
-		   (cond
-			((string-match-p "finished" event)
-			 (message "✓ Finished playing: %s" url-display))
-			((string-match-p "exited abnormally" event)
-			 (message "✗ Playback failed: %s" url-display)))
-		   (when (string-match-p "finished\\|exited" event)
-			 (kill-buffer (process-buffer proc)))))))))
+		(set-process-sentinel process (cj/media--play-sentinel url-display))))))
 
 ;; ------------------------- Media-Download Via yt-dlp -------------------------
 
diff --git a/tests/test-media-utils.el b/tests/test-media-utils.el
index c682dffe..23b36eeb 100644
--- a/tests/test-media-utils.el
+++ b/tests/test-media-utils.el
@@ -114,6 +114,40 @@ launches the player with the resolved URL as argv -- no shell either step."
       (should-error (cj/media-play-it "https://example.com/v")))
     (should-not launched)))
 
+;; -------------------------- cj/media--play-sentinel --------------------------
+
+(ert-deftest test-media-utils--play-sentinel-normal-finished-kills-buffer ()
+  "Normal: a finished event reports success and reaps the process buffer."
+  (let ((buf (generate-new-buffer " *sentinel-test*"))
+        (said nil))
+    (cl-letf (((symbol-function 'process-buffer) (lambda (_p) buf))
+              ((symbol-function 'message)
+               (lambda (fmt &rest args) (setq said (apply #'format fmt args)))))
+      (funcall (cj/media--play-sentinel "https://a/v") 'proc "finished\n"))
+    (should (string-match-p "Finished" said))
+    (should-not (buffer-live-p buf))))
+
+(ert-deftest test-media-utils--play-sentinel-normal-abnormal-exit-kills-buffer ()
+  "Normal: an abnormal exit reports failure and reaps the process buffer."
+  (let ((buf (generate-new-buffer " *sentinel-test*"))
+        (said nil))
+    (cl-letf (((symbol-function 'process-buffer) (lambda (_p) buf))
+              ((symbol-function 'message)
+               (lambda (fmt &rest args) (setq said (apply #'format fmt args)))))
+      (funcall (cj/media--play-sentinel "https://a/v") 'proc "exited abnormally with code 2\n"))
+    (should (string-match-p "failed" said))
+    (should-not (buffer-live-p buf))))
+
+(ert-deftest test-media-utils--play-sentinel-boundary-other-event-keeps-buffer ()
+  "Boundary: a non-terminal event (e.g. stop) leaves the buffer alone."
+  (let ((buf (generate-new-buffer " *sentinel-test*")))
+    (unwind-protect
+        (cl-letf (((symbol-function 'process-buffer) (lambda (_p) buf))
+                  ((symbol-function 'message) #'ignore))
+          (funcall (cj/media--play-sentinel "https://a/v") 'proc "stopped\n")
+          (should (buffer-live-p buf)))
+      (when (buffer-live-p buf) (kill-buffer buf)))))
+
 ;; ------------------------------- cj/yt-dl-it ---------------------------------
 
 (ert-deftest test-media-yt-dl-it-errors-without-yt-dlp ()