From aad170d1edf70485995aafbabf4af6f4bcbca192 Mon Sep 17 00:00:00 2001
From: Rahul Martim Juliato <rahul.juliato@gmail.com>
Date: Tue, 19 May 2026 17:26:09 -0300
Subject: [PATCH] markdown-ts-mode: hide fence lines in view-mode (bug#81081)

* lisp/textmodes/markdown-ts-mode.el
(markdown-ts--fontify-delimiter): When `markdown-ts-hide-markup'
is enabled in `markdown-ts-view-mode', also hide the whole line
containing a `fenced_code_block_delimiter' (including its
terminating newline) so Eldoc/LSP markdown snippets render
without stray blank lines around the code block.  Scoped to
view-mode and to fenced delimiters on purpose: the same handler
is shared by inline delimiters (emphasis, code span, link
brackets) where munching surrounding whitespace would collapse
word separators, and tuning rendering for
hide-markup-while-editing is not a goal.
---
 lisp/textmodes/markdown-ts-mode.el | 23 +++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/lisp/textmodes/markdown-ts-mode.el b/lisp/textmodes/markdown-ts-mode.el
index 01b7ac09995..7f87ff5d0bc 100644
--- a/lisp/textmodes/markdown-ts-mode.el
+++ b/lisp/textmodes/markdown-ts-mode.el
@@ -842,8 +842,27 @@ OVERRIDE, START, and END are passed through to
    (treesit-node-start node) (treesit-node-end node)
    'markdown-ts-delimiter override start end)
   (when markdown-ts-hide-markup
-    (put-text-property (treesit-node-start node) (treesit-node-end node)
-                       'invisible 'markdown-ts--markup)))
+    (if (and (derived-mode-p 'markdown-ts-view-mode)
+             (equal (treesit-node-type node) "fenced_code_block_delimiter"))
+        ;; In view-mode only, hide the whole line containing the fence
+        ;; (including its terminating newline) so Eldoc/LSP markdown
+        ;; snippets render without stray blank lines around the code
+        ;; block.  Restricted to view-mode because hide-markup while
+        ;; editing already has UX hazards (point movement, backspace
+        ;; across invisible regions) and we should not tune rendering
+        ;; for that mode.  Restricted to fenced_code_block_delimiter
+        ;; because the same handler is shared by inline delimiters
+        ;; (emphasis, code span, link brackets) where munching
+        ;; surrounding whitespace would collapse word separators.
+        (save-excursion
+          (goto-char (treesit-node-start node))
+          (let ((bol (pos-bol))
+                (eol+1 (progn (goto-char (treesit-node-end node))
+                              (min (point-max) (1+ (pos-eol))))))
+            (put-text-property bol eol+1
+                               'invisible 'markdown-ts--markup)))
+      (put-text-property (treesit-node-start node) (treesit-node-end node)
+                         'invisible 'markdown-ts--markup))))
 
 (defun markdown-ts--fontify-atx-delimiter (node override start end &rest _)
   "Fontify atx_heading delimiter NODE and optionally hide its markup.