tools/eval: add +overlay feature

Now, inline evaluation will display results in an overlay next to the
cursor, rather than in the minibuffer (unless it gets too big, in which
case it'll use a popup buffer).

modules/tools/eval/autoload/eval.el

@@ -1,5 +1,51 @@
 ;;; tools/eval/autoload/eval.el -*- lexical-binding: t; -*-
 
+;;;###autoload
+(defun +eval-display-results-in-popup (output &optional source-buffer)
+  "Display OUTPUT in a popup buffer."
+  (let ((output-buffer (get-buffer-create "*doom eval*"))
+        (origin (selected-window)))
+    (with-current-buffer output-buffer
+      (setq-local scroll-margin 0)
+      (erase-buffer)
+      (insert output)
+      (goto-char (point-min))
+      (if (fboundp '+word-wrap-mode)
+          (+word-wrap-mode +1)
+        (visual-line-mode +1)))
+    (when-let (win (display-buffer output-buffer))
+      (fit-window-to-buffer win))
+    (select-window origin)
+    output-buffer))
+
+;;;###autoload
+(defun +eval-display-results-in-overlay (output &optional source-buffer)
+  "Display OUTPUT in a floating overlay next to the cursor."
+  (let ((this-command #'+eval/buffer-or-region)
+        eros-overlays-use-font-lock)
+    (with-current-buffer (or source-buffer (current-buffer))
+      (eros--make-result-overlay output
+        :where (line-end-position)
+        :duration eros-eval-result-duration))))
+
+;;;###autoload
+(defun +eval-display-results (output &optional source-buffer)
+  "Display OUTPUT in an overlay or a popup buffer."
+  (funcall (if (and (or current-prefix-arg
+                        (with-temp-buffer
+                          (insert output)
+                          (>= (count-lines (point-min) (point-max))
+                              +eval-overlay-max-lines)))
+                    (require 'eros nil t))
+               #'+eval-display-results-in-popup
+             #'+eval-display-results-in-overlay)
+           output source-buffer)
+  output)
+
+
+;;
+;;; Commands
+
 ;;;###autoload
 (defun +eval/buffer ()
   "Evaluate the whole buffer."