Python overwriting glyph; RF GlyphInfoPane error

rdmcmurray

RF 3.5
Big Sur 11.0.1

I am working on a plugin for copying layers between files. I have run across an error (included below) when copying glyphs multiple times.

I have reduced the repro to these steps using the following script:

font1 = CurrentFont()

font2 = OpenFont(showInterface=False)

for glyph in font2:
	font1.defaultLayer[glyph.name] = glyph

Open new/blank font.
Run the below copy script, choosing a second font. In my case, I used a new font that contains only an exclamation glyph on foreground.
Select the newly copied exclamation/whichever glyph in GlyphInfoPane.
Repeat step 2, same font. The twice copied glyph sorts to the bottom of the GlyphInfoPane for some reason?
Repeat step 3. This error is thrown:

Observer '<lib.UI.inspector.glyphInfoPane.GlyphInfoPane object at 0x14b192a50>' with '_currentGlyphChanged' failed: An observer is only allowed to have one callback for a given notification + observable combination. notification=Lib.Changed, observable={'com.defcon.sortDescriptor': [{'ascending': 'Latin-1', 'type': 'characterSet'}], 'com.robofont.generateFeaturesWithFontTools': False, 'com.typemytype.robofont.compileSettings.autohint': True, 'com.typemytype.robofont.compileSettings.checkOutlines': False, 'com.typemytype.robofont.compileSettings.createDummyDSIG': True, 'com.typemytype.robofont.compileSettings.decompose': False, 'com.typemytype.robofont.compileSettings.generateFormat': 0, 'com.typemytype.robofont.compileSettings.releaseMode': False, 'com.typemytype.robofont.italicSlantOffset': 0, 'com.typemytype.robofont.segmentType': 'curve', 'com.typemytype.robofont.shouldAddPointsInSplineConversion': 1, 'com.typemytype.robofont.smartSets.uniqueKey': '5204840272', 'public.glyphOrder': ['space', 'quotesingle', 'quotedbl', 'numbersign', 'dollar', 'percent', 'ampersand', 'parenleft', 'parenright', 'asterisk', 'plus', 'comma', 'hyphen', 'period', 'slash', 'zero', 'one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine', 'colon', 'semicolon', 'less', 'equal', 'greater', 'question', 'at', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'bracketleft', 'backslash', 'bracketright', 'asciicircum', 'underscore', 'grave', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'braceleft', 'bar', 'braceright', 'asciitilde', 'exclamdown', 'cent', 'sterling', 'currency', 'yen', 'brokenbar', 'section', 'dieresis', 'copyright', 'ordfeminine', 'guillemetleft', 'logicalnot', 'registered', 'macron', 'degree', 'plusminus', 'twosuperior', 'threesuperior', 'acute', 'mu', 'paragraph', 'periodcentered', 'cedilla', 'onesuperior', 'ordmasculine', 'guillemetright', 'onequarter', 'onehalf', 'threequarters', 'questiondown', 'Agrave', 'Aacute', 'Acircumflex', 'Atilde', 'Adieresis', 'Aring', 'AE', 'Ccedilla', 'Egrave', 'Eacute', 'Ecircumflex', 'Edieresis', 'Igrave', 'Iacute', 'Icircumflex', 'Idieresis', 'Eth', 'Ntilde', 'Ograve', 'Oacute', 'Ocircumflex', 'Otilde', 'Odieresis', 'multiply', 'Oslash', 'Ugrave', 'Uacute', 'Ucircumflex', 'Udieresis', 'Yacute', 'Thorn', 'germandbls', 'agrave', 'aacute', 'acircumflex', 'atilde', 'adieresis', 'aring', 'ae', 'ccedilla', 'egrave', 'eacute', 'ecircumflex', 'edieresis', 'igrave', 'iacute', 'icircumflex', 'idieresis', 'eth', 'ntilde', 'ograve', 'oacute', 'ocircumflex', 'otilde', 'odieresis', 'divide', 'oslash', 'ugrave', 'uacute', 'ucircumflex', 'udieresis', 'yacute', 'thorn', 'ydieresis', 'dotlessi', 'circumflex', 'caron', 'breve', 'dotaccent', 'ring', 'ogonek', 'tilde', 'hungarumlaut', 'quoteleft', 'quoteright', 'minus', 'exclam'], 'public.postscriptNames': {}, 'public.skipExportGlyphs': []} , observer=<lib.UI.inspector.glyphInfoPane.GlyphInfoPane object at 0x14b192a50>, existing method=libChanged, adding method=libChanged
Traceback (most recent call last):
  File "lib/eventTools/eventManager.pyc", line 132, in callObserver_withMethod_forEvent_withInfo_
  File "lib/UI/inspector/basePane.pyc", line 88, in _currentGlyphChanged
  File "lib/UI/inspector/basePane.pyc", line 58, in _subscribeGlyph
  File "lib/UI/inspector/glyphInfoPane.pyc", line 359, in subscribeGlyph
  File "/Applications/RoboFont.app/Contents/Resources/lib/python3.7/defcon/objects/base.py", line 101, in addObserver
  File "/Applications/RoboFont.app/Contents/Resources/lib/python3.7/defcon/tools/notifications.py", line 82, in addObserver
AssertionError: An observer is only allowed to have one callback for a given notification + observable combination. notification=Lib.Changed, observable={'com.defcon.sortDescriptor': [{'ascending': 'Latin-1', 'type': 'characterSet'}], 'com.robofont.generateFeaturesWithFontTools': False, 'com.typemytype.robofont.compileSettings.autohint': True, 'com.typemytype.robofont.compileSettings.checkOutlines': False, 'com.typemytype.robofont.compileSettings.createDummyDSIG': True, 'com.typemytype.robofont.compileSettings.decompose': False, 'com.typemytype.robofont.compileSettings.generateFormat': 0, 'com.typemytype.robofont.compileSettings.releaseMode': False, 'com.typemytype.robofont.italicSlantOffset': 0, 'com.typemytype.robofont.segmentType': 'curve', 'com.typemytype.robofont.shouldAddPointsInSplineConversion': 1, 'com.typemytype.robofont.smartSets.uniqueKey': '5204840272', 'public.glyphOrder': ['space', 'quotesingle', 'quotedbl', 'numbersign', 'dollar', 'percent', 'ampersand', 'parenleft', 'parenright', 'asterisk', 'plus', 'comma', 'hyphen', 'period', 'slash', 'zero', 'one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine', 'colon', 'semicolon', 'less', 'equal', 'greater', 'question', 'at', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'bracketleft', 'backslash', 'bracketright', 'asciicircum', 'underscore', 'grave', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'braceleft', 'bar', 'braceright', 'asciitilde', 'exclamdown', 'cent', 'sterling', 'currency', 'yen', 'brokenbar', 'section', 'dieresis', 'copyright', 'ordfeminine', 'guillemetleft', 'logicalnot', 'registered', 'macron', 'degree', 'plusminus', 'twosuperior', 'threesuperior', 'acute', 'mu', 'paragraph', 'periodcentered', 'cedilla', 'onesuperior', 'ordmasculine', 'guillemetright', 'onequarter', 'onehalf', 'threequarters', 'questiondown', 'Agrave', 'Aacute', 'Acircumflex', 'Atilde', 'Adieresis', 'Aring', 'AE', 'Ccedilla', 'Egrave', 'Eacute', 'Ecircumflex', 'Edieresis', 'Igrave', 'Iacute', 'Icircumflex', 'Idieresis', 'Eth', 'Ntilde', 'Ograve', 'Oacute', 'Ocircumflex', 'Otilde', 'Odieresis', 'multiply', 'Oslash', 'Ugrave', 'Uacute', 'Ucircumflex', 'Udieresis', 'Yacute', 'Thorn', 'germandbls', 'agrave', 'aacute', 'acircumflex', 'atilde', 'adieresis', 'aring', 'ae', 'ccedilla', 'egrave', 'eacute', 'ecircumflex', 'edieresis', 'igrave', 'iacute', 'icircumflex', 'idieresis', 'eth', 'ntilde', 'ograve', 'oacute', 'ocircumflex', 'otilde', 'odieresis', 'divide', 'oslash', 'ugrave', 'uacute', 'ucircumflex', 'udieresis', 'yacute', 'thorn', 'ydieresis', 'dotlessi', 'circumflex', 'caron', 'breve', 'dotaccent', 'ring', 'ogonek', 'tilde', 'hungarumlaut', 'quoteleft', 'quoteright', 'minus', 'exclam'], 'public.postscriptNames': {}, 'public.skipExportGlyphs': []} , observer=<lib.UI.inspector.glyphInfoPane.GlyphInfoPane object at 0x14b192a50>, existing method=libChanged, adding method=libChanged
Observer '<lib.UI.inspector.guidelinesPane.GuidelinesPane object at 0x116925fd0>' with '_currentGlyphChanged' failed: An observer is only allowed to have one callback for a given notification + observable combination. notification=Font.GuidelinesChanged, observable=<lib.fontObjects.doodleFont.DoodleFont object at 0x136c74550> , observer=<lib.UI.inspector.guidelinesPane.GuidelinesPane object at 0x116925fd0>, existing method=fontGuidelinesChanged, adding method=fontGuidelinesChanged
Traceback (most recent call last):
  File "lib/eventTools/eventManager.pyc", line 132, in callObserver_withMethod_forEvent_withInfo_
  File "lib/UI/inspector/basePane.pyc", line 88, in _currentGlyphChanged
  File "lib/UI/inspector/basePane.pyc", line 58, in _subscribeGlyph
  File "lib/UI/inspector/guidelinesPane.pyc", line 152, in subscribeGlyph
  File "/Applications/RoboFont.app/Contents/Resources/lib/python3.7/defcon/objects/base.py", line 101, in addObserver
  File "/Applications/RoboFont.app/Contents/Resources/lib/python3.7/defcon/tools/notifications.py", line 82, in addObserver
AssertionError: An observer is only allowed to have one callback for a given notification + observable combination. notification=Font.GuidelinesChanged, observable=<lib.fontObjects.doodleFont.DoodleFont object at 0x136c74550> , observer=<lib.UI.inspector.guidelinesPane.GuidelinesPane object at 0x116925fd0>, existing method=fontGuidelinesChanged, adding method=fontGuidelinesChanged

frederik

what font1.defaultLayer[glyph.name] = glyph does:

check if the glyph already exists: if it exist it will be removed from that layer: so that the reason why the glyph is at the end of the glyph order in the font overview. (as that glyph is also removed from the glyph order)
create a new glyph
draw the given glyph in the newly created glyph

I cannot reproduce the error, based on your instructions. I will flag this to investigate.

rdmcmurray

@rdmcmurray

I realized the resorting in step 4 is normal behavior, derp.

UNSOLVED Python overwriting glyph; RF GlyphInfoPane error