[GX] Move XML generation for GlyphVariations into separate method

Lib/fontTools/ttLib/tables/_g_v_a_r.py

@@ -260,32 +260,8 @@ class table__g_v_a_r(DefaultTable.DefaultTable):
 				continue
 			writer.begintag("glyphVariation", glyph=glyphName)
 			writer.newline()
-			for tupleIndex in xrange(len(tuples)):
+			for tuple in tuples:
-				tuple = tuples[tupleIndex]
+				tuple.toXML(writer, axisTags)
-				writer.begintag("tuple")
-				writer.newline()
-				for axis in axisTags:
-					value = tuple.axes.get(axis)
-					if value != None:
-						minValue, value, maxValue = value
-						if minValue == value and maxValue == value:
-							writer.simpletag("coord", axis=axis, value=value)
-						else:
-							writer.simpletag("coord", axis=axis, value=value,
-									 min=minValue, max=maxValue)
-						writer.newline()
-				wrote_any_points = False
-				for i in xrange(len(tuple.coordinates)):
-					x, y = tuple.coordinates[i]
-					if x != 0 or y != 0:
-						writer.simpletag("delta", pt=i, x=x, y=y)
-						writer.newline()
-						wrote_any_points = True
-				if not wrote_any_points:
-					writer.comment("all deltas are (0,0)")
-					writer.newline()
-				writer.endtag("tuple")
-				writer.newline()
 			writer.endtag("glyphVariation")
 			writer.newline()
 
@@ -298,3 +274,29 @@ class GlyphVariation:
 	def __repr__(self):
 		axes = ",".join(sorted(['%s=%s' % (name, value) for (name, value) in self.axes.items()]))
 		return '<GlyphVariation %s %s>' % (axes, self.coordinates)
+
+	def toXML(self, writer, axisTags):
+		writer.begintag("tuple")
+		writer.newline()
+		for axis in axisTags:
+			value = self.axes.get(axis)
+			if value != None:
+				minValue, value, maxValue = value
+				if minValue == value and maxValue == value:
+					writer.simpletag("coord", axis=axis, value=value)
+				else:
+					writer.simpletag("coord", axis=axis, value=value,
+							 min=minValue, max=maxValue)
+				writer.newline()
+		wrote_any_points = False
+		for i in xrange(len(self.coordinates)):
+			x, y = self.coordinates[i]
+			if x != 0 or y != 0:
+				writer.simpletag("delta", pt=i, x=x, y=y)
+				writer.newline()
+				wrote_any_points = True
+		if not wrote_any_points:
+			writer.comment("all deltas are (0,0)")
+			writer.newline()
+		writer.endtag("tuple")
+		writer.newline()

Lib/fontTools/ttLib/tables/_g_v_a_r_test.py

@@ -1,10 +1,11 @@
 from __future__ import print_function, division, absolute_import, unicode_literals
 from fontTools.misc.py23 import *
+from fontTools.misc.xmlWriter import XMLWriter
 from fontTools import ttLib
 import unittest
+from fontTools.ttLib.tables._g_l_y_f import GlyphCoordinates
 from fontTools.ttLib.tables._g_v_a_r import table__g_v_a_r, GlyphVariation
 
-
 def hexdecode(s):
 	return bytesjoin([c.decode("hex") for c in s.split()])
 
@@ -167,5 +168,40 @@ class GlyphVariationTableTest(unittest.TestCase):
 		self.assertEqual(([0, 0, 0, 0, 258, -127, -128], 11), decompileDeltas(7, data, 4))
 
 
+class GlyphVariationTest(unittest.TestCase):
+	def test_toXML(self):
+		writer = XMLWriter(StringIO())
+		axes = {"wdth":(0.3, 0.4, 0.5), "wght":(1.0, 1.0, 1.0)}
+		g = GlyphVariation(axes, GlyphCoordinates([(9,8), (7,6), (0,0), (-1,-2)]))
+		g.toXML(writer, ["wght", "wdth"])
+		self.assertEqual([
+			'<tuple>',
+			  '<coord axis="wght" value="1.0"/>',
+			  '<coord axis="wdth" max="0.5" min="0.3" value="0.4"/>',
+			  '<delta pt="0" x="9" y="8"/>',
+			  '<delta pt="1" x="7" y="6"/>',
+			  '<delta pt="3" x="-1" y="-2"/>',
+			'</tuple>'
+		], GlyphVariationTest.xml_lines(writer))
+
+	def test_toXML_allDeltasZero(self):
+		writer = XMLWriter(StringIO())
+		axes = {"wdth":(0.3, 0.4, 0.5), "wght":(1.0, 1.0, 1.0)}
+		g = GlyphVariation(axes, GlyphCoordinates.zeros(5))
+		g.toXML(writer, ["wght", "wdth"])
+		self.assertEqual([
+			'<tuple>',
+			  '<coord axis="wght" value="1.0"/>',
+			  '<coord axis="wdth" max="0.5" min="0.3" value="0.4"/>',
+			  '<!-- all deltas are (0,0) -->',
+			'</tuple>'
+		], GlyphVariationTest.xml_lines(writer))
+
+	@staticmethod
+	def xml_lines(writer):
+		content = writer.file.getvalue().decode("utf-8")
+		return [line.strip() for line in content.splitlines()][1:]
+
+
 if __name__ == "__main__":
 	unittest.main()