Merge pull request #2366 from fonttools/fix-tt-point-pen-move

[TTGlyphPen] Fix NotImplementedError with open contours

Lib/fontTools/pens/ttGlyphPen.py

@@ -275,10 +275,11 @@ class TTGlyphPointPen(_TTGlyphBasePen, LogMixin, AbstractPointPen):
             raise PenError("Can't add a point to a closed contour.")
         if segmentType is None:
             self.types.append(0)  # offcurve
-        elif segmentType in ("qcurve", "line"):
+        elif segmentType in ("qcurve", "line", "move"):
             self.types.append(1)  # oncurve
+        elif segmentType == "curve":
+            raise NotImplementedError("cubic curves are not supported")
         else:
-            # cubic curves are not supported
-            raise NotImplementedError
+            raise AssertionError(segmentType)
 
         self.points.append(pt)

Tests/pens/ttGlyphPen_test.py

@@ -549,6 +549,32 @@ class TTGlyphPointPenTest(TTGlyphPenTestBase):
         uni0302_uni0300.recalcBounds(glyphSet)
         self.assertGlyphBoundsEqual(uni0302_uni0300, (-278, 745, 148, 1025))
 
+    def test_open_path_starting_with_move(self):
+        # when a contour starts with a 'move' point, it signifies the beginnig
+        # of an open contour.
+        # https://unifiedfontobject.org/versions/ufo3/glyphs/glif/#point-types
+        pen1 = TTGlyphPointPen(None)
+        pen1.beginPath()
+        pen1.addPoint((0, 0), "move")  # contour is open
+        pen1.addPoint((10, 10), "line")
+        pen1.addPoint((20, 20))
+        pen1.addPoint((20, 0), "qcurve")
+        pen1.endPath()
+
+        pen2 = TTGlyphPointPen(None)
+        pen2.beginPath()
+        pen2.addPoint((0, 0), "line")  # contour is closed
+        pen2.addPoint((10, 10), "line")
+        pen2.addPoint((20, 20))
+        pen2.addPoint((20, 0), "qcurve")
+        pen2.endPath()
+
+        # Since TrueType contours are always implicitly closed, the pen will
+        # interpret both these paths as equivalent
+        assert pen1.points == pen2.points == [(0, 0), (10, 10), (20, 20), (20, 0)]
+        assert pen1.types == pen2.types == [1, 1, 0, 1]
+
+
 
 class _TestGlyph(object):
     def __init__(self, glyph):