diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el index 81440cfcfc9..594681594b0 100644 --- a/lisp/progmodes/python.el +++ b/lisp/progmodes/python.el @@ -2386,9 +2386,54 @@ backward to previous statement." (python-nav-beginning-of-statement) (setq arg (1+ arg)))) +(defvar python-nav-cache nil + "Cache to hold the results of navigation functions.") + +(defvar python-nav-cache-tick 0 + "`buffer-chars-modified-tick' when registering the navigation cache.") + +(defun python-nav-cache-get (kind) + "Get value from the navigation cache. +If the current buffer is not modified, the navigation cache is searched +using KIND and the current line number as a key." + (and (= (buffer-chars-modified-tick) python-nav-cache-tick) + (cdr (assoc (cons kind (line-number-at-pos nil t)) python-nav-cache)))) + +(defun python-nav-cache-set (kind current target) + "Add a key-value pair to the navigation cache. +Invalidate the navigation cache if the current buffer has been modified. +Then add a key-value pair to the navigation cache. The key consists of +KIND and CURRENT line number, and the value is TARGET position." + (let ((tick (buffer-chars-modified-tick))) + (when (/= tick python-nav-cache-tick) + (setq-local python-nav-cache nil + python-nav-cache-tick tick)) + (push (cons (cons kind current) target) python-nav-cache) + target)) + +(defun python-nav-with-cache (kind func) + "Cached version of the navigation FUNC. +If a value is obtained from the navigation cache using KIND, it will +navigate there and return the position. Otherwise, use FUNC to navigate +and cache the result." + (let ((target (python-nav-cache-get kind))) + (if target + (progn + (goto-char target) + (point-marker)) + (let ((current (line-number-at-pos nil t))) + (python-nav-cache-set kind current (funcall func)))))) + (defun python-nav-beginning-of-block () "Move to start of current block." (interactive "^") + (python-nav-with-cache + 'beginning-of-block #'python-nav--beginning-of-block)) + +(defun python-nav--beginning-of-block () + "Move to start of current block. +This is an internal implementation of `python-nav-beginning-of-block' +without the navigation cache." (let ((starting-pos (point))) ;; Go to first line beginning a statement (while (and (not (bobp)) @@ -2413,6 +2458,13 @@ backward to previous statement." (defun python-nav-end-of-block () "Move to end of current block." (interactive "^") + (python-nav-with-cache + 'end-of-block #'python-nav--end-of-block)) + +(defun python-nav--end-of-block () + "Move to end of current block. +This is an internal implementation of `python-nav-end-of-block' without +the navigation cache." (when (python-nav-beginning-of-block) (let ((block-indentation (current-indentation))) (python-nav-end-of-statement)