What the...
I cannot for the life of me get what I assume is the desired behavior working:
Being able to consistently switch some behavior of the Filter Bar.
The Preferences dialog says "The options menu on the bar can override them during use", and the command Set has QUICKFILTERFLAGS, which surely should be doing something.
In March, a symptom of what I assume to be the same issue was already reported but never commented on.
Depending on whether the main settings (Preferences / Filtering and Sorting / Filter Bar: Regular Expression) is set, I get the following behavior.
If it is set:
regexpoffsometimes clears the filter bar's content but never turns RegExp off. The button's appearance does not change (remains off).
regexpon understandably doesn't change anything, but the button's appearance switches between on and off.
same for regexp
If it is not set, the inverse is true.
Sometimes in my testing worked for just a second, only to then immediately break again, without changing anything.
I tried explicitly set,regexpon, and I tried combining every setting of regexpon with a clear,regexpoff, both before and after attempting to set it, as well as the reverse.
same for regexp
I just tried it, even though the docs only list regexpon and regexpoff, and for a moment, Set QUICKFILTERFLAGS=regexp seemed to be the most reliable way I could toggle the setting (because it broke soon after when I tried the onand off flags). When it worked, I assumed the documentation was incomplete/misleading.
It suddenly started working again for a moment, so I recorded it:
And again, when I tried using the regular flags again as documented, everything stopped working again.
There must be a bug in there somewhere.
Is there a way for me to log what's happening?
TLDR:Steps to repeat at the bottom.
My observations and explanations in the mean time:
There seems to be incongruity between the "Main" Filter Bar that may come up when a filter is set (or is turned on or off via Preferences / Filtering and Sorting / Filter Bar => "Display Filter Bar") and a (label?) field set to "Filter", and possibly a small one between toggling regexpoff and regexpon.
I always have a Filter field visible in my bottom toolbar, and I think this contributes to the problem. (Does that field come with its own parser?)
(I observed the following while Preferences / Filtering and Sorting / Filter Bar => "Regular expression" is turned off)
Since I have Preferences / Filtering and Sorting / Filter Bar => "Display Filter Bar" set to "Whenever a filter is set", I'll refer to the "Main" filter bar as the "Ad-Hoc Filter Bar", and the Filter Bar added via Field => type "Filter" as just "Filter Bar".
Unless stated otherwise, filter inputs are done in the "Field" Filter Bar.
I think I can get it to work by having the quick filter bar visible and turning RegExp on from its options menu (which usually clears the filter field), then typing in a valid filter.
If the "Display Filter Bar" setting in Preferences / Filtering and Sorting / Filter Bar is set to "Always", I can Set QUICKFILTERFLAGS=regexpoff. setting Set QUICKFILTERFLAGS=regexpon after that doesn't do anything at first, but doing it again will turn it back on.
Now, when the "Display Filter Bar" setting in Preferences / Filtering and Sorting / Filter Bar is set to "Whenever a filter is set", I run into trouble after Set QUICKFILTERFLAGS=regexpoff.
Now, trying to Set QUICKFILTERFLAGS=regexpon just flashes the lister's "filtered view" color for a split second if the filter bar is empty, or briefly flashes the filtered-out files and the regular background color in the lister if there is a filter string in the filter bar, but RegExp remains turned off.
Trying to Set QUICKFILTERFLAGS=clear,regexpoff in this state does nothing either.
It also seems inconsistent when trying to toggle RegExp mode clears the Filter Bar's contents and when it doesn't; I haven't found the pattern. Except it always seems to clear it at the moment when I run Set QUICKFILTERFLAGS=regexpon from the CLI, while it doesn't when run from a button.
Steps to hopefully repeat a breaking case:
Set Preferences / Filtering and Sorting / Filter Bar => "Display Filter Bar" to "Whenever a filter is set"
Turn Preferences / Filtering and Sorting / Filter Bar => "Regular expression" off
Have a (label?) field set to "Filter" accessible in a toolbar
Be in a folder with files with a number, and files without a number in its name.
Turn "Use regular expression" in the Ad-Hoc FIlter Bar's settings menu on (type something in the Filter Bar to access it, or use the assigned shortcut)
check sanity by filtering with a string that will only work as a RegExp, like "\d", which should hide the files without a number in their names
use a button or the DOpus CLI etc, to Set QUICKFILTERFLAGS=regexpoff
If this clears the Filter field, all files should now be visible
If it doesn't, no files should now be visible, because they don't match the filter "\d" if it's not a RegExp
use a button or the DOpus CLI etc, to Set QUICKFILTERFLAGS=regexpon
Set the Filter to "\d" again. All files remain hidden for me. Expected behavior is that files with a number be made visible again, because they match the pattern as RegExp.
Try any combination of setting, clearing regexpon and regexpoff to no avail until the Ad-Hoc Filter Bar's option menu is set to use Regular expressions again manually.
Shot in the dark: Is code skipped when the Ad-Hoc Filter Bar isn't necessarily on?
I hope this helps.
Let me know if I can try to do some more sleuthing in the mean time.