Rework displaying source line with new hook dape-display-source-hook

Pulse has an huge performance hit on macOS and as it's the spirit of
dape to do configuration by hooks, add another.

This allows to easily restore old pulse behavior like:
`(add-hook 'dape-display-source-hook
 'pulse-momentary-highlight-one-line)`

README.org

@@ -60,6 +60,9 @@ Screenshots taken with [[https://elpa.gnu.org/packages/standard-themes.html][sta
     ;; Global bindings for setting breakpoints with mouse
     ;; (dape-breakpoint-global-mode)
 
+    ;; Pulse source line (performance hit)
+    ;; (add-hook 'dape-display-source-hook 'pulse-momentary-highlight-one-line)
+
     ;; To not display info and/or buffers on startup
     ;; (remove-hook 'dape-start-hook 'dape-info)
     ;; (remove-hook 'dape-start-hook 'dape-repl)

dape.el

@@ -510,6 +510,10 @@ present in an group."
   "Called when it's sensible to refresh UI."
   :type 'hook)
 
+(defcustom dape-display-source-hook '()
+  "Called in buffer when placing overlay arrow for stack frame."
+  :type 'hook)
+
 (defcustom dape-memory-page-size 1024
   "The bytes read with `dape-read-memory'."
   :type 'natnum)
@@ -523,9 +527,8 @@ present in an group."
   "Align columns in variable tables."
   :type 'boolean)
 
-(defcustom dape-info-variable-table-row-config `((name . 20)
-                                                 (value . 50)
-                                                 (type . 20))
+(defcustom dape-info-variable-table-row-config
+  `((name . 20) (value . 50) (type . 20))
   "Configuration for table rows of variables.
 
 An alist that controls the display of the name, type and value of
@@ -673,9 +676,9 @@ The hook is run with one argument, the compilation buffer."
   '((t :extend t :inherit (error tooltip)))
   "Face used to display exception descriptions inline.")
 
-(defface dape-stack-trace-face
-  '((t :extend t))
-  "Face used to display stack trace overlays.")
+(defface dape-source-line-face
+  '((t))
+  "Face used to display stack frame source line overlays.")
 
 (defface dape-repl-success-face
   '((t :inherit compilation-mode-line-exit :extend t))
@@ -1782,7 +1785,8 @@ selected stack frame."
         (dolist (frame (plist-get thread :stackFrames))
           (plist-put frame :scopes nil)))))
     (dape--with-request (dape--stack-trace conn current-thread 1)
-      (dape--stack-frame-display conn display)
+      (when display
+        (dape--stack-frame-display conn))
       (dape--with-request (dape--scopes conn (dape--current-stack-frame conn))
         (run-hooks 'dape-update-ui-hook)))))
 
@@ -3129,7 +3133,7 @@ See `dape-request' for expected CB signature."
             (dape--request-return cb)))))))))
 
 
-;;; Stack frame
+;;; Stack frame source
 
 (defvar dape--overlay-arrow-position (make-marker)
   "Dape stack position marker.")
@@ -3149,9 +3153,8 @@ See `dape-request' for expected CB signature."
     (delete-overlay dape--stack-position-overlay))
   (set-marker dape--overlay-arrow-position nil))
 
-(defun dape--stack-frame-display (conn display)
+(defun dape--stack-frame-display (conn)
   "Update stack frame arrow marker for adapter CONN.
-When DISPLAY is non nil display buffer if possible with
 `dape-display-source-buffer-action'."
   (dape--stack-frame-cleanup)
   (when-let (((dape--stopped-threads conn))
@@ -3162,47 +3165,45 @@ When DISPLAY is non nil display buffer if possible with
         ;; An update event could have fired between call to
         ;; `dape--stack-frame-cleanup' and callback, we have make
         ;; sure that overlay is deleted before we are dropping the
-        ;; reference.
+        ;; reference
         (dape--stack-frame-cleanup)
         (when-let ((marker (dape--object-to-marker conn frame)))
-          (when display
-            (when-let ((window
-                        (display-buffer (marker-buffer marker)
-                                        dape-display-source-buffer-action)))
-              ;; Change selected window if not dape-repl buffer is selected
-              (unless (with-current-buffer (window-buffer)
-                        (memq major-mode '(dape-repl-mode)))
-                (select-window window))
-              ;; FIXME Should be called with idle-timer as to
-              ;;       guarantee that we are not in `save-excursion'
-              ;;       context.  But this makes tests to hard write.
-              (with-selected-window window
-                (goto-char (marker-position marker))
-                (pulse-momentary-highlight-region (line-beginning-position)
-                                                  (line-beginning-position 2)
-                                                  'next-error))))
           (with-current-buffer (marker-buffer marker)
             (dape--add-eldoc-hook)
             (save-excursion
               (goto-char (marker-position marker))
               (setq dape--stack-position-overlay
                     (let ((ov (make-overlay (line-beginning-position)
                                             (line-beginning-position 2))))
-                      (overlay-put ov 'face 'dape-stack-trace-face)
+                      (overlay-put ov 'face 'dape-source-line-face)
                       (when deepest-p
                         (when-let ((exception-description
                                     (dape--exception-description conn)))
                           (overlay-put ov 'after-string
-                                        (propertize (concat exception-description "\n")
-                                                    'face
-                                                    'dape-exception-description-face))))
-                      ov))
-              (setq fringe-indicator-alist
+                                       (propertize (concat exception-description "\n")
+                                                   'face
+                                                   'dape-exception-description-face))))
+                      ov)
+                    fringe-indicator-alist
                     (unless deepest-p
                       '((overlay-arrow . hollow-right-triangle))))
               ;; Finally lets move arrow to point
               (move-marker dape--overlay-arrow-position
-                           (line-beginning-position)))))))))
+                           (line-beginning-position)))
+            (when-let ((window
+                        (display-buffer (marker-buffer marker)
+                                        dape-display-source-buffer-action)))
+              ;; Change selected window if not dape-repl buffer is selected
+              (unless (with-current-buffer (window-buffer)
+                        (memq major-mode '(dape-repl-mode)))
+                (select-window window))
+              ;; FIXME Should be called with idle-timer as to
+              ;;       guarantee that we are not in `save-excursion'
+              ;;       context.  But this makes tests to hard write.
+              (with-selected-window window
+                (goto-char (marker-position marker))
+                (run-hooks 'dape-display-source-hook)))))))))
+
 
 ;;; Info Buffers