Merge from origin/emacs-31

4f13f52a3aa * build-aux/git-hooks/commit-msg: Replace Markdown-style ...
dd42133315b vc-test--rename-file: Disable part of test for SCCS
eb653865c3a markdown-ts-mode: Don't enable unconditionally by default

# Conflicts:
#	etc/NEWS

4 files changed, 35 insertions, 26 deletions

diff --git a/build-aux/git-hooks/commit-msg b/build-aux/git-hooks/commit-msg
index 159990b1406..ddde1b4e586 100755
--- a/build-aux/git-hooks/commit-msg
+++ b/build-aux/git-hooks/commit-msg
@@ -75,6 +75,7 @@ exec $awk \
     }
     c_lower = "abcdefghijklmnopqrstuvwxyz"
     unsafe_gnu_url = "(http|ftp)://([" c_lower ".]*\\.)?(gnu|fsf)\\.org"
+    markdown_quotation = "(^|[^\\\\])`[^'\''`]+`"
   }
 
   { input[NR] = $0 }
@@ -92,11 +93,6 @@ exec $awk \
     status = 1
   }
 
-  /(^|[^\\])`[^'\''`]+`/ {
-    print "Markdown-style quotes in commit message"
-    status = 1
-  }
-
   nlines == 0 && $0 !~ non_space { next }
 
   { nlines++ }
@@ -141,7 +137,7 @@ exec $awk \
     status = 1
   }
 
-  $0 ~ unsafe_gnu_url {
+  $0 ~ unsafe_gnu_url || $0 ~ markdown_quotation {
     needs_rewriting = 1
   }
 
@@ -167,7 +163,13 @@ exec $awk \
 	  suffix = substr(line, RSTART)
 	  line = prefix "https:" substr(suffix, 5 + (suffix ~ /^http:/))
 	}
-	print line >file
+	while (match(line, markdown_quotation)) {
+	  prefix = substr(line, 1, RSTART)
+	  within = substr(line, RSTART + 2, RLENGTH - 3)
+	  suffix = substr(line, RSTART + RLENGTH)
+	  line = prefix "'\''" within "'\''" suffix
+	}
+        print line >file
       }
       if (close(file) != 0) {
 	print "Cannot rewrite: " file
diff --git a/etc/NEWS.31 b/etc/NEWS.31
index 083e6b50ea4..7fc998ff547 100644
--- a/etc/NEWS.31
+++ b/etc/NEWS.31
@@ -3938,19 +3938,12 @@ A major mode based on 'conf-mode' for editing ".npmrc" files.
 
 *** New major mode 'markdown-ts-mode'.
 A major mode based on the tree-sitter library for editing Markdown
-files.  This is now the default major mode for Markdown files.  If you
-don't have the necessary tree-sitter grammar libraries installed, or if
-your Emacs was built without tree-sitter support, Emacs will now show a
-warning to that effect when you visit a Markdown file.  If you don't
-want to use this mode and want to avoid these warnings, add the
-following to your init file:
+files.  Markdown files are visited using this mode when the required
+tree-sitter grammars ('markdown' and 'markdown-inline') are available,
+or when the user has opted in via 'treesit-enabled-modes'.  Otherwise,
+Markdown files fall back to 'text-mode'.
 
-  (add-to-list 'auto-mode-alist '("\\.md\\'" . fundamental-mode))
-  (add-to-list 'auto-mode-alist '("\\.markdown\\'" . fundamental-mode))
-  (add-to-list 'auto-mode-alist '("\\.mdx\\'" . fundamental-mode))
-
-This will cause Emacs to visit Markdown files in Fundamental mode, which
-was the default before this mode was added to Emacs.
+To install the grammars, use 'M-x markdown-ts-mode-install-parsers'.
 
 *** New major mode 'mhtml-ts-mode'.
 An optional major mode based on the tree-sitter library for editing HTML
diff --git a/lisp/textmodes/markdown-ts-mode.el b/lisp/textmodes/markdown-ts-mode.el
index be2247b870e..fed6ded192c 100644
--- a/lisp/textmodes/markdown-ts-mode.el
+++ b/lisp/textmodes/markdown-ts-mode.el
@@ -5401,14 +5401,14 @@ With a prefix argument, ARG, if needed, install parsers for `html',
     (cond ((treesit-ready-p '(markdown markdown-inline) t)
            (markdown-ts--set-up))
           (t
-           (warn "markdown-ts-mode cannot be set up; using fundamental-mode.
+           (warn "markdown-ts-mode cannot be set up; using text-mode.
 %s."
                  (if (treesit-available-p)
                      "The tree-sitter parsers `markdown' and `markdown-inline' were not found.
 Use the command `markdown-ts-mode-install-parsers' to install them.
 With a prefix argument, it can also install optional parsers"
                    "Emacs was built without Tree-sitter support, or could not load Tree-sitter"))
-           (fundamental-mode)))))
+           (text-mode)))))
 
 ;;;###autoload
 (define-derived-mode markdown-ts-mode text-mode "Markdown"
@@ -5620,10 +5620,24 @@ If non-nil and `point' is in a table, enable
                       #'markdown-ts--enable-in-table-mode 'local))))
 
 ;;;###autoload
+(defun markdown-ts-mode-maybe ()
+  "Enable `markdown-ts-mode' when its grammars are available.
+Also propose to install the grammars when `treesit-enabled-modes'
+is t or contains the mode name."
+  (declare-function treesit-language-available-p "treesit.c")
+  (if (or (and (treesit-language-available-p 'markdown)
+               (treesit-language-available-p 'markdown-inline))
+          (eq treesit-enabled-modes t)
+          (memq 'markdown-ts-mode treesit-enabled-modes))
+      (markdown-ts-mode)
+    (text-mode)))
+
+;;;###autoload
 (when (boundp 'treesit-major-mode-remap-alist)
-  (add-to-list 'auto-mode-alist '("\\.md\\'" . markdown-ts-mode))
-  (add-to-list 'auto-mode-alist '("\\.markdown\\'" . markdown-ts-mode))
-  (add-to-list 'auto-mode-alist '("\\.mdx\\'" . markdown-ts-mode))
+  (add-to-list 'auto-mode-alist '("\\.md\\'"        . markdown-ts-mode-maybe))
+  (add-to-list 'auto-mode-alist '("\\.markdown\\'"  . markdown-ts-mode-maybe))
+  (add-to-list 'auto-mode-alist '("\\.mdx\\'"       . markdown-ts-mode-maybe))
+  ;; To be able to toggle between an external package and core ts-mode:
   (add-to-list 'treesit-major-mode-remap-alist
                '(markdown-mode . markdown-ts-mode)))
 
diff --git a/test/lisp/vc/vc-tests/vc-tests.el b/test/lisp/vc/vc-tests/vc-tests.el
index 1fb17842478..8e2ae2c4454 100644
--- a/test/lisp/vc/vc-tests/vc-tests.el
+++ b/test/lisp/vc/vc-tests/vc-tests.el
@@ -592,8 +592,8 @@ This checks also `vc-backend' and `vc-responsible-backend'."
                                'added))))
 
             ;; Test OK-IF-ALREADY-EXISTS.
-            ;; RCS and SRC don't support `vc-delete-file'.
-            (unless (memq backend '(RCS SRC))
+            ;; RCS, SRC and SCCS don't support `vc-delete-file'.
+            (unless (memq backend '(RCS SRC SCCS))
               (let ((tmp-name (expand-file-name "qux" default-directory))
                     (new-name (expand-file-name "quuux" default-directory)))
                 (write-region "qux" nil tmp-name nil 'nomessage)