Save match data in markdown-syntax-propertize-extend-region

[syohex]

This function should not overwrite match data.

I suppose this is related to following issues

• Can markdown-mode cause problems with query-replace? #104
• :s/from/to/g only replaces one occurence in markdown-mode syl20bnr/spacemacs#5203

[jrblevin]

Thanks for tracking this down. Were you able to reproduce #104? I wasn't, so I can't check whether this helps.

[syohex]

Were you able to reproduce #104?

No.

However I suppose we can confirm this with simple code.

(defun test-command ()
  (interactive)
  (beginning-of-line)
  (when (re-search-forward "foo" nil t)
    (let ((beg0 (match-beginning 0)))
      (insert "A") ;; <- markdown-syntax-propertize-extend-region is called
      (cl-assert (= beg0 (match-beginning 0))))))

Open following markdown file

abcdefg

foo<- move cursor here and do M-x test-command

With original code, match data is overwritten and assertion is failed, while assertion is not failed with this patch.

[jrblevin]

Thanks for confirming, and for the patch!