test_incompatible.py

"""
The contours from https://gist.github.com/rsheeter/cef6cf71fa9e519c94f9f0d23906e5de are in fact not compatible
and this even before we attempt to reverse them.

See https://github.com/fonttools/fonttools/issues/3093
"""
from ufoLib2 import Font
from ufo2ft import compileInterpolatableTTFs


# same routine as Rod's original gist:
# https://gist.github.com/rsheeter/cef6cf71fa9e519c94f9f0d23906e5de
def draw(pen, endp):
    pen.moveTo((0, 0))
    pen.curveTo((1,1), (2,2), (3,3))
    pen.curveTo((4,4), (5,5), endp)
    pen.closePath()


font1 = Font()
g = font1.newGlyph("A")
draw(g.getPen(), endp=(0, 0))

font2 = Font()
g = font2.newGlyph("A")
draw(g.getPen(), endp=(6, 6))

# reverseDirection=False so ReverseContourPen can't be blamed for this
for ttf in compileInterpolatableTTFs([font1, font2], reverseDirection=False):
    # we never get here because cu2qu throws
    # IncompatibleFontsError: fonts contains incompatible glyphs: 'A'
    # That is not a bug, it's a feature.
    print(ttf)

I guess I don't agree that isn't a bug :)