Filters update late after setting Display

[Chadnaut]

Using ::fe.set_display sometimes fails to update ::fe.filters immediately.
Calling ::fe.set_display a second time fixes ::fe.filters.
Occurs on Windows 10, cannot reproduce in Ubuntu 22.04.4.

The loop is intended to scrape display filters to generate global stats.

layout.nut

local f_names = function() { local n = ""; foreach (f in ::fe.filters) n += f.name + ", "; return n; }
local nv_key = "STATS_RUNNING";
if (!(nv_key in ::fe.nv)) ::fe.nv[nv_key] <- false;
if (!::fe.nv[nv_key]) {
    local original = ::fe.list.display_index;
    local f1, f2, data = [];
    foreach (i, display in ::fe.displays) {
        ::fe.set_display(i, false, false);
        f1 = f_names();
        data.push(format("Before %d: '%s' (%d filters)    %s", ::fe.list.display_index, display.name, ::fe.filters.len(), f1));

        ::fe.set_display(i, false, false); // hack
        f2 = f_names();
        data.push(format("After  %d: '%s' (%d filters)%s %s", ::fe.list.display_index, display.name, ::fe.filters.len(), f1 != f2 ? "<--" : "   ", f2));
    }
    ::fe.set_display(original, false, false);
    ::fe.nv[nv_key] <- true;
    foreach (item in data) ::fe.log(item);
} else {
    delete ::fe.nv[nv_key];
}

last_run.log

Before 0: 'Mame' (6 filters)    All, Favourites, 2UP, MameFilter, Top, 4UP, 
After  0: 'Mame' (6 filters)    All, Favourites, 2UP, MameFilter, Top, 4UP, 
Before 1: 'C64' (6 filters)    All, Favourites, 2UP, MameFilter, Top, 4UP, 
After  1: 'C64' (5 filters)<-- All, Favourites, Extra, More, C64Filter, 
Before 2: 'MD' (4 filters)    All, Favourites, Extra, MDFilter, 
After  2: 'MD' (4 filters)    All, Favourites, Extra, MDFilter, 
Before 3: 'N64' (4 filters)    All, Favourites, Extra, MDFilter, 
After  3: 'N64' (4 filters)<-- All, Favourites, More, N64Filter, 
Before 4: 'SMS' (4 filters)    All, Favourites, More, N64Filter, 
After  4: 'SMS' (5 filters)<-- All, Favourites, More, Extra, SMSFilter, 
Before 5: 'SNES' (4 filters)    All, Favourites, Extra, SNESFilter, 
After  5: 'SNES' (4 filters)    All, Favourites, Extra, SNESFilter, 

The arrows <-- indicate where ::fe.filters has changed on the second call.

Attract-Mode Plus v3.0.8

[oomek]

I think it's the time to consider adding the filters table to fe.Displays that would have size field for each filter and make it cached, so the filter's list is not regenerated on every display change unless the cfg file has changed.
Catch me up on Discord so we can discuss the details.

[oomek]

I could fix the above code, but it's just a workaround for a long overdue AM shortcoming.

[Chadnaut]

The loop is an edge-case, a non-standard (ab)use of AM, and is unlikely to occur "in the wild".
Not essential to fix, just keep it in mind if you ever refactor the lists.