Pan-sahelian keyboard (NFD) needs to reorder diacritics

[darcywong00]

Steps to reproduce:

1. Create bookmarklet for Fulfulde, Adamawa Keyboard

javascript: void((function() {
    try {
        var e = document.createElement('script');
        e.type = 'text/javascript';
        e.src = 'https://r.keymanweb.com/code/bml20.php?langid=fub&keyboard=ps32&lang=Fulfulde%2C Adamawa pan-Sahelian (v. 3.2)%26font%3D%7B"family"%3A"LatinWeb"%2C"source"%3A%5B"DejaVuSans.ttf"%2C"DejaVuSans.mobileconfig"%5D%2C"files"%3A%5B"DejaVuSans.ttf"%2C"DejaVuSans.mobileconfig"%5D%2C"path"%3A"https%3A%2F%2Fs.keyman.com%2Ffont%2Fdeploy%2F"%7D';
        document.body.appendChild(e);
    } catch (v) {}
})())

2. Use the bookmarklet on a website
3. Using the Pan-sahelian keyboard, type w + 2 + 9 ==> ẃ̩

The resulting diacritics (U+0301) + (U+0329) are in the wrong order

[DavidLRowe]

If you type w + 9 + 2 are the diacritics in the correct order? Do keyboards have to guarantee that the output is perfectly formed? If so, I suspect there are a lot of keyboards that wouldn't qualify!

[andjc]

@darcywong00 does this problem also occurs in windows version? Or just the js version? And which version of pan-sahelian?

[darcywong00]

Sorry, I see that I created this issue. But I'm drawing a blank if it was on behalf of someone, or from a legacy issue report.

[DavidLRowe]

I think the keyboard is this one: https://github.com/keymanapp/keyboards/tree/master/legacy/p/ps32

[andjc]

I had a look at the source to see what is happening.

1. ther eis no js version, was never developed for KMW or bookmarklets.
2. there are ordering constraints for diacritics but these only come into play with the vowels.
3. A sequence such as

w + 2 + 9 ==> ẃ̩

was never explicitly intended.

Probably easiest fix is to prevent use of 2 or more diacriitcs with consonants, or alternatively restrict consonants that can have combining diacritics.

Will add it to my post contract task list

[andjc]

Although layout is probably in need of updated research and a complete overhaul and rewrite. It is quite old now.