Add predicate to exclude open files from being added to recentf

[punassuming]

Fixes #4973 , recentf will no longer add files to the list that have never been viewed.

[punassuming]

This should clear all the org files loading from org-agenda and any other major mode that loads files for information without the intent to view them. Because we are taking a snapshot of the recentf-list at init to keep the files that were not viewed this session, it might take clearing the recentf-list completely to get the non-viewed files off the list.

[bmag]

why setf and not add-to-list? By overriding the existing value, we risk interfering with user's personal configuration.

[caikechao]

Maybe I met a new issue here or maybe not. But I'd like to ask you guys first ...

If I set the dotspacemacs-startup-lists as follows,

   dotspacemacs-startup-lists '(agenda recents bookmarks projects)

then the recentf-exclude variable will be reset to nil (originally, spacemacs sets it to be ("COMMIT_EDITMSG\\'" "/home/user/.emacs.d/elpa" "/home/user/.emacs.d/.cache/")

But if I change the order of the startup list like as follows,

   dotspacemacs-startup-lists '(recents agenda bookmarks projects)

then the recentf-exclude will be the default value set by spacemacs.

I don't know why this happened... I really want the agenda list to be at the top of the home buffer without affecting the recentf-exclude set by spacemacs ... Could you help?

[punassuming]

@bmag, awesome I didn't realize recentf-keep accepted lists of funcs. Will update the PR.

[punassuming]

@kccai, is this after applying this PR, or in the current develop branch?

[caikechao]

@Ralesi
I am in the current develop branch, not applying this PR. Hoping that this PR could solve this problem. Thanks~

[punassuming]

@bmag, I updated with your suggestions, much better just adding to the recentf-keep list. Thanks.

[punassuming]

@kccai , I do not see the same issue as you. Perhaps you can make an issue with the steps to repo?

[caikechao]

@Ralesi Thanks, I will check it again and create an issue if this problem persists.

[punassuming]

I am finding that org files are still being added, testing out applying changes as an exclude predicate.

[syl20bnr]

What's the status on this PR ?

[punassuming]

@syl20bnr, I have got it working, but if agenda is listed before recent files in the startup list, the org files still get added. Will get it fixed and update the PR tonight.

[syl20bnr]

@Ralesi thank you 👍

[punassuming]

@syl20bnr , I take that back. I cannot come up with a method to keep the recentf-list clean during startup. The method with the predicate works, but requires one to run recentf-cleanup after load, which is enough of a preference that I don't think it should be added to one of the default hooks. Optimally, we would have an exclusion predicate placed on recentf-exclude if the opened file is not viewed, but that hook runs right after after-find-file and the buffer is not completely set by set-window, which is what increments the buffer display counter.

If anyone else has other ideas to get this to work consistently with the additional org file loading at startup, I would be open to ideas.

[punassuming]

@syl20bnr, i updated and the current implementation works for me. I created a variable that will bypass recentf saving if let bound. I have also bound it on my call to org-refile in my own config to prevent that function from adding all the org files to my recent list.