From b283eb7eec428b8b0027a28f8c5f547360386b80 Mon Sep 17 00:00:00 2001 From: Spencer Baugh Date: Tue, 27 Jun 2023 15:25:02 -0400 Subject: [PATCH] Add project-watch to discover projects with file-notify Projects can be created outside of Emacs, but users might want to be able to switch to them with project-switch-project immediately. This API supports that. If a user calls (project-watch "~/src" 1) then any projects under ~/src will be discovered automatically immediately after their creation. * lisp/progmodes/project.el (project-check-project) (project--watch-cb-children, project--watch-cb-this) (project--file-notify-watch, project-watch): Add. (bug#63870) --- lisp/progmodes/project.el | 51 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) diff --git a/lisp/progmodes/project.el b/lisp/progmodes/project.el index 56c524bcab5..ddb033d50f9 100644 --- a/lisp/progmodes/project.el +++ b/lisp/progmodes/project.el @@ -1884,5 +1884,56 @@ project-switch-project (let ((project-current-directory-override dir)) (call-interactively command)))) +(defun project-check-project (dir) + "If there's a project at DIR, remember it; otherwise, forget it. + +Return the found project, if any." + (let ((pr (project--find-in-directory dir))) + (if pr (project-remember-project pr) + (project-forget-project (file-name-as-directory dir))) + pr)) + +(defun project--watch-cb-children (recursive predicate event) + (unless (eq (cl-second event) 'stopped) + (dolist (file (cddr event)) + (condition-case _ (project-watch file recursive predicate) + ((file-error file-notify-error)))))) + +(defun project--watch-cb-this (dir event) + (unless (eq (cl-second event) 'stopped) + (when (project-check-project dir) + (file-notify-rm-watch (cl-first event))))) + +(defun project--file-notify-watch (dir callback &optional init) + "Like `file-notify-add-watch' but also calls CALLBACK immediately." + (let ((watch (file-notify-add-watch dir '(change) callback))) + (funcall callback (append (list watch 'started) init)))) + +;;;###autoload +(defun project-watch (dir &optional recursive predicate) + "Watch DIR until it becomes a project. + +We stop watching DIR once it becomes a project. + +If RECURSIVE is an integer greater than 0, we'll also run +`project-watch' on directories which appear inside DIR, +passing (1- RECURSIVE) as RECURSIVE. To achieve this, we'll +continue watching DIR even if it becomes a project. This can be +expensive, so it's better to pass small values of RECURSIVE, like +1 or 2. + +If PREDICATE is non-nil, it should be a function which will be +called with two arguments, the value of RECURSIVE and a +directory. Only directories for which PREDICATE returns non-nil +will be watched for being a project." + (setq predicate (or predicate (lambda (_recursive dir) t))) + (setq recursive (or recursive 0)) + (when (and (funcall predicate recursive dir) (file-directory-p dir)) + (project--file-notify-watch dir (apply-partially #'project--watch-cb-this dir))) + (when (> recursive 0) + (project--file-notify-watch + dir (apply-partially #'project--watch-cb-children (1- recursive) predicate) + (directory-files dir 'full directory-files-no-dot-files-regexp)))) + (provide 'project) ;;; project.el ends here -- 2.39.3