From f565a9f3187ae99680ec92969bb3f6c29b542b04 Mon Sep 17 00:00:00 2001 Message-ID: From: Ihor Radchenko Date: Mon, 19 Feb 2024 12:19:34 +0300 Subject: [PATCH] Work around regexp size limitation for large number of link targets MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * lisp/ol.el (org-target-link-regexp-limit): New constant defining maximum regexp limit where `org-target-link-regexp' is still safe to use without triggering "Regexp too long" error. (org-target-link-regexps): New variable holding a series of shorter regexps to be used instead of too long single `org-target-link-regexp'. (org--re-list-search-forward): New function like `re-search-forward', but accepting a list of regexps. (org--re-list-looking-at): New function like `looking-at', but accepting a list of regexps. (org-update-radio-target-regexp): When `org-target-link-regexp' is too long, set `org-target-link-regexps', partitioning the link target list into smaller regexps. * lisp/org-element.el (org-element-link-parser): (org-element--object-lex): * lisp/org.el (org-activate-target-links): Use `org--re-list-search-forward' and `org--re-list-looking-at' when `org-target-link-regexps' is non-nil. * testing/lisp/test-org-element.el (test-org-element/link-parser): Add tests. Reported-by: Rudolf Adamkovič Link: https://list.orgmode.org/orgmode/m2lenax5m6.fsf@me.com/ --- lisp/ol.el | 68 ++++++++++++++++++++++++++++++-- lisp/org-element.el | 16 ++++++-- lisp/org.el | 4 +- testing/lisp/test-org-element.el | 17 ++++++++ 4 files changed, 97 insertions(+), 8 deletions(-) diff --git a/lisp/ol.el b/lisp/ol.el index 22782578c..97423738a 100644 --- a/lisp/ol.el +++ b/lisp/ol.el @@ -52,6 +52,7 @@ (declare-function org-before-first-heading-p "org" ()) (declare-function org-do-occur "org" (regexp &optional cleanup)) (declare-function org-element-at-point "org-element" (&optional pom cached-only)) (declare-function org-element-cache-refresh "org-element" (pos)) +(declare-function org-element-cache-reset "org-element" (&optional all no-persistence)) (declare-function org-element-context "org-element" (&optional element)) (declare-function org-element-lineage "org-element-ast" (datum &optional types with-self)) (declare-function org-element-link-parser "org-element" ()) @@ -532,6 +533,13 @@ (defconst org-radio-target-regexp (format "<%s>" org-target-regexp) (defvar-local org-target-link-regexp nil "Regular expression matching radio targets in plain text.") +(defconst org-target-link-regexp-limit (ash 2 10) + "Maximum allowed length of regexp. +See MAX_BUF_SIZE in src/regex-emacs.c") +(defvar-local org-target-link-regexps nil + "List of regular expressions matching radio targets in plain text. +This list is non-nil, when a single regexp would be too long to match +all the possible targets, exceeding Emacs' regexp length limit.") (defvar org-link-types-re nil "Matches a link that has a url-like prefix like \"http:\".") @@ -2170,6 +2178,34 @@ (defun org-insert-link-global () (org-load-modules-maybe) (org-run-like-in-org-mode 'org-insert-link)) +(defun org--re-list-search-forward (regexp-list &optional bound noerror count) + "Like `re-search-forward', but REGEXP-LIST is a list of regexps. +BOUND, NOERROR, and COUNT are passed to `re-search-forward'." + (let (result (min-found most-positive-fixnum) + (pos-found nil) + (min-found-data nil) + (tail regexp-list)) + (while tail + (setq result (save-excursion (re-search-forward (pop tail) bound t count))) + (when (and result (< result min-found)) + (setq min-found result + pos-found (match-end 0) + min-found-data (match-data)))) + (if (= most-positive-fixnum min-found) + (pcase noerror + (`t nil) + (_ (re-search-forward (car regexp-list) bound noerror count))) + (set-match-data min-found-data) + (goto-char pos-found)))) + +(defun org--re-list-looking-at (regexp-list &optional inhibit-modify) + "Like `looking-at', but REGEXP-LIST is a list of regexps. +INHIBIT-MODIFY is passed to `looking-at'." + (catch :found + (while regexp-list + (when (looking-at (pop regexp-list) inhibit-modify) + (throw :found t))))) + ;;;###autoload (defun org-update-radio-target-regexp () "Find all radio targets in this file and update the regular expression. @@ -2207,6 +2243,30 @@ (defun org-update-radio-target-regexp () targets "\\|") after-re))) + (setq org-target-link-regexps nil) + (let (current-length sub-targets) + (when (<= org-target-link-regexp-limit (length org-target-link-regexp)) + (while (or targets sub-targets) + (when (and sub-targets + (or (not targets) + (>= (+ current-length (length (car targets))) + org-target-link-regexp-limit))) + (push (concat before-re + (mapconcat + (lambda (x) + (replace-regexp-in-string + " +" "\\s-+" (regexp-quote x) t t)) + (nreverse sub-targets) + "\\|") + after-re) + org-target-link-regexps) + (setq current-length nil + sub-targets nil)) + (unless current-length + (setq current-length (+ (length before-re) (length after-re)))) + (when targets (push (pop targets) sub-targets)) + (cl-incf current-length (length (car sub-targets)))) + (setq org-target-link-regexps (nreverse org-target-link-regexps)))) (unless (equal old-regexp org-target-link-regexp) ;; Clean-up cache. (let ((regexp (cond ((not old-regexp) org-target-link-regexp) @@ -2222,9 +2282,11 @@ (defun org-update-radio-target-regexp () after-re))))) (when (and (featurep 'org-element) (not (bound-and-true-p org-mode-loading))) - (org-with-point-at 1 - (while (re-search-forward regexp nil t) - (org-element-cache-refresh (match-beginning 1)))))) + (if org-target-link-regexps + (org-element-cache-reset) + (org-with-point-at 1 + (while (re-search-forward regexp nil t) + (org-element-cache-refresh (match-beginning 1))))))) ;; Re fontify buffer. (when (memq 'radio org-highlight-links) (org-restart-font-lock))))) diff --git a/lisp/org-element.el b/lisp/org-element.el index 573de0106..c490dcd29 100644 --- a/lisp/org-element.el +++ b/lisp/org-element.el @@ -3848,7 +3848,9 @@ (defun org-element-link-parser () ;; Type 1: Text targeted from a radio target. ((and org-target-link-regexp (save-excursion (or (bolp) (backward-char)) - (looking-at org-target-link-regexp))) + (if org-target-link-regexps + (org--re-list-looking-at org-target-link-regexps) + (looking-at org-target-link-regexp)))) (setq type "radio") (setq format 'plain) (setq link-end (match-end 1)) @@ -5221,7 +5223,10 @@ (defun org-element--object-lex (restriction) ((not (memq 'link restriction)) nil) ((progn (unless (bolp) (forward-char -1)) - (not (re-search-forward org-target-link-regexp nil t))) + (not + (if org-target-link-regexps + (org--re-list-search-forward org-target-link-regexps nil t) + (re-search-forward org-target-link-regexp nil t)))) nil) ;; Since we moved backward, we do not want to ;; match again an hypothetical 1-character long @@ -5230,8 +5235,11 @@ (defun org-element--object-lex (restriction) ;; beginning of line, we prevent this here. ((and (= start (1+ (line-beginning-position))) (= start (match-end 1))) - (and (re-search-forward org-target-link-regexp nil t) - (1+ (match-beginning 1)))) + (and + (if org-target-link-regexps + (org--re-list-search-forward org-target-link-regexps nil t) + (re-search-forward org-target-link-regexp nil t)) + (1+ (match-beginning 1)))) (t (1+ (match-beginning 1)))))) found) (save-excursion diff --git a/lisp/org.el b/lisp/org.el index 28f43cb67..89cc8bdd9 100644 --- a/lisp/org.el +++ b/lisp/org.el @@ -5710,7 +5710,9 @@ (defun org-activate-target-links (limit) ;; `org-target-link-regexp' matches one character before the ;; actual target. (unless (bolp) (forward-char -1)) - (when (re-search-forward org-target-link-regexp limit t) + (when (if org-target-link-regexps + (org--re-list-search-forward org-target-link-regexps limit t) + (re-search-forward org-target-link-regexp limit t)) (org-remove-flyspell-overlays-in (match-beginning 1) (match-end 1)) (add-text-properties (match-beginning 1) (match-end 1) (list 'mouse-face 'highlight diff --git a/testing/lisp/test-org-element.el b/testing/lisp/test-org-element.el index 93754bae5..61cd70693 100644 --- a/testing/lisp/test-org-element.el +++ b/testing/lisp/test-org-element.el @@ -2378,6 +2378,23 @@ (ert-deftest test-org-element/link-parser () (org-element-property :type (org-element-map (org-element-parse-buffer) 'link #'identity nil t))))) + (should + (equal + "radio" + (org-test-with-temp-text "<<>><<>><<>>A radio link" + (org-update-radio-target-regexp) + (org-element-property + :type + (org-element-map (org-element-parse-buffer) 'link #'identity nil t))))) + (should + (equal + "radio" + (let ((org-target-link-regexp-limit 9)) + (org-test-with-temp-text "<<>><<>><<>>A radio link" + (org-update-radio-target-regexp) + (org-element-property + :type + (org-element-map (org-element-parse-buffer) 'link #'identity nil t)))))) ;; Pathological case: radio target of length 1 at beginning of line ;; not followed by spaces. (should -- 2.43.0