I made a quick script to change kerning groups and it works on most of the cases, but it hungs up if the font is really big.

I really don’t know if I’m doing it correctly. So any help is really appreciated.

here a sample code:

from fontParts.world import *

fontPath = 'myFont.ufo'
font = OpenFont(fontPath, showInterface=False)
glyphs = font.keys()


def removeGlyphFromKerningGroups(glyph):
    currentGroups = font.groups.findGlyph(glyph.name)
    for groupName in currentGroups:
        group = font.groups[groupName]
        groupList = list(font.groups[groupName])
        groupList.remove(glyph.name)
        font.groups[groupName] = tuple(groupList)

def getKerningGroups(glyphName, side):
    if side == 1:
        groups = font.groups.side1KerningGroups
    else:
        groups = font.groups.side2KerningGroups
    glyphGroups = []
    for key in groups:
        for value in groups[key]:
            if glyphName == value:
                glyphGroups.append(key)
    return glyphGroups


for thisGlyphName in glyphs:
    thisGlyph = font[thisGlyphName]
    if thisGlyphName.endswith(".sc"):
        basename = thisGlyphName.split(".")[0]
        removeGlyphFromKerningGroups(thisGlyph)

        side1Groups = getKerningGroups(basename, 1)
        for side1Group in side1Groups:
            kern1Group = font.groups[side1Group]
            kern1GroupList = list(kern1Group)
            kern1GroupList.append(thisGlyph.name) 
            font.groups[side1Group] = tuple(kern1GroupList)
        
        side2Groups = getKerningGroups(basename, 2)
        for side2Group in side2Groups:
            kern2Group = font.groups[side2Group]
            kern2GroupList = list(kern2Group)
            kern2GroupList.append(thisGlyph.name) 
            font.groups[side2Group] = tuple(kern2GroupList)   
        
          
        currentGroups = font.groups.findGlyph(thisGlyph.name)
        print (thisGlyph.name, currentGroups)

Thanks in advance.

can you provide an dummy ufo where this happens?

you can get a font’s groups as a dict with font.groups.asDict()

hope that helps!