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path: root/Tests/ttLib/tables/TupleVariation_test.py
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from fontTools.misc.loggingTools import CapturingLogHandler
from fontTools.misc.testTools import parseXML
from fontTools.misc.textTools import deHexStr, hexStr
from fontTools.misc.xmlWriter import XMLWriter
from fontTools.ttLib.tables.TupleVariation import (
    log,
    TupleVariation,
    compileSharedTuples,
    decompileSharedTuples,
    compileTupleVariationStore,
    decompileTupleVariationStore,
    inferRegion_,
)
from io import BytesIO
import random
import unittest


def hexencode(s):
    h = hexStr(s).upper()
    return " ".join([h[i : i + 2] for i in range(0, len(h), 2)])


AXES = {
    "wdth": (0.25, 0.375, 0.5),
    "wght": (0.0, 1.0, 1.0),
    "opsz": (-0.75, -0.75, 0.0),
}


# Shared tuples in the 'gvar' table of the Skia font, as printed
# in Apple's TrueType specification.
# https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6gvar.html
SKIA_GVAR_SHARED_TUPLES_DATA = deHexStr(
    "40 00 00 00 C0 00 00 00 00 00 40 00 00 00 C0 00 "
    "C0 00 C0 00 40 00 C0 00 40 00 40 00 C0 00 40 00"
)

SKIA_GVAR_SHARED_TUPLES = [
    {"wght": 1.0, "wdth": 0.0},
    {"wght": -1.0, "wdth": 0.0},
    {"wght": 0.0, "wdth": 1.0},
    {"wght": 0.0, "wdth": -1.0},
    {"wght": -1.0, "wdth": -1.0},
    {"wght": 1.0, "wdth": -1.0},
    {"wght": 1.0, "wdth": 1.0},
    {"wght": -1.0, "wdth": 1.0},
]


# Tuple Variation Store of uppercase I in the Skia font, as printed in Apple's
# TrueType spec. The actual Skia font uses a different table for uppercase I
# than what is printed in Apple's spec, but we still want to make sure that
# we can parse the data as it appears in the specification.
# https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6gvar.html
SKIA_GVAR_I_DATA = deHexStr(
    "00 08 00 24 00 33 20 00 00 15 20 01 00 1B 20 02 "
    "00 24 20 03 00 15 20 04 00 26 20 07 00 0D 20 06 "
    "00 1A 20 05 00 40 01 01 01 81 80 43 FF 7E FF 7E "
    "FF 7E FF 7E 00 81 45 01 01 01 03 01 04 01 04 01 "
    "04 01 02 80 40 00 82 81 81 04 3A 5A 3E 43 20 81 "
    "04 0E 40 15 45 7C 83 00 0D 9E F3 F2 F0 F0 F0 F0 "
    "F3 9E A0 A1 A1 A1 9F 80 00 91 81 91 00 0D 0A 0A "
    "09 0A 0A 0A 0A 0A 0A 0A 0A 0A 0A 0B 80 00 15 81 "
    "81 00 C4 89 00 C4 83 00 0D 80 99 98 96 96 96 96 "
    "99 80 82 83 83 83 81 80 40 FF 18 81 81 04 E6 F9 "
    "10 21 02 81 04 E8 E5 EB 4D DA 83 00 0D CE D3 D4 "
    "D3 D3 D3 D5 D2 CE CC CD CD CD CD 80 00 A1 81 91 "
    "00 0D 07 03 04 02 02 02 03 03 07 07 08 08 08 07 "
    "80 00 09 81 81 00 28 40 00 A4 02 24 24 66 81 04 "
    "08 FA FA FA 28 83 00 82 02 FF FF FF 83 02 01 01 "
    "01 84 91 00 80 06 07 08 08 08 08 0A 07 80 03 FE "
    "FF FF FF 81 00 08 81 82 02 EE EE EE 8B 6D 00"
)


class TupleVariationTest(unittest.TestCase):
    def __init__(self, methodName):
        unittest.TestCase.__init__(self, methodName)
        # Python 3 renamed assertRaisesRegexp to assertRaisesRegex,
        # and fires deprecation warnings if a program uses the old name.
        if not hasattr(self, "assertRaisesRegex"):
            self.assertRaisesRegex = self.assertRaisesRegexp

    def test_equal(self):
        var1 = TupleVariation({"wght": (0.0, 1.0, 1.0)}, [(0, 0), (9, 8), (7, 6)])
        var2 = TupleVariation({"wght": (0.0, 1.0, 1.0)}, [(0, 0), (9, 8), (7, 6)])
        self.assertEqual(var1, var2)

    def test_equal_differentAxes(self):
        var1 = TupleVariation({"wght": (0.0, 1.0, 1.0)}, [(0, 0), (9, 8), (7, 6)])
        var2 = TupleVariation({"wght": (0.7, 0.8, 0.9)}, [(0, 0), (9, 8), (7, 6)])
        self.assertNotEqual(var1, var2)

    def test_equal_differentCoordinates(self):
        var1 = TupleVariation({"wght": (0.0, 1.0, 1.0)}, [(0, 0), (9, 8), (7, 6)])
        var2 = TupleVariation({"wght": (0.0, 1.0, 1.0)}, [(0, 0), (9, 8)])
        self.assertNotEqual(var1, var2)

    def test_hasImpact_someDeltasNotZero(self):
        axes = {"wght": (0.0, 1.0, 1.0)}
        var = TupleVariation(axes, [(0, 0), (9, 8), (7, 6)])
        self.assertTrue(var.hasImpact())

    def test_hasImpact_allDeltasZero(self):
        axes = {"wght": (0.0, 1.0, 1.0)}
        var = TupleVariation(axes, [(0, 0), (0, 0), (0, 0)])
        self.assertTrue(var.hasImpact())

    def test_hasImpact_allDeltasNone(self):
        axes = {"wght": (0.0, 1.0, 1.0)}
        var = TupleVariation(axes, [None, None, None])
        self.assertFalse(var.hasImpact())

    def test_toXML_badDeltaFormat(self):
        writer = XMLWriter(BytesIO())
        g = TupleVariation(AXES, ["String"])
        with CapturingLogHandler(log, "ERROR") as captor:
            g.toXML(writer, ["wdth"])
        self.assertIn("bad delta format", [r.msg for r in captor.records])
        self.assertEqual(
            [
                "<tuple>",
                '<coord axis="wdth" min="0.25" value="0.375" max="0.5"/>',
                "<!-- bad delta #0 -->",
                "</tuple>",
            ],
            TupleVariationTest.xml_lines(writer),
        )

    def test_toXML_constants(self):
        writer = XMLWriter(BytesIO())
        g = TupleVariation(AXES, [42, None, 23, 0, -17, None])
        g.toXML(writer, ["wdth", "wght", "opsz"])
        self.assertEqual(
            [
                "<tuple>",
                '<coord axis="wdth" min="0.25" value="0.375" max="0.5"/>',
                '<coord axis="wght" value="1.0"/>',
                '<coord axis="opsz" value="-0.75"/>',
                '<delta cvt="0" value="42"/>',
                '<delta cvt="2" value="23"/>',
                '<delta cvt="3" value="0"/>',
                '<delta cvt="4" value="-17"/>',
                "</tuple>",
            ],
            TupleVariationTest.xml_lines(writer),
        )

    def test_toXML_points(self):
        writer = XMLWriter(BytesIO())
        g = TupleVariation(AXES, [(9, 8), None, (7, 6), (0, 0), (-1, -2), None])
        g.toXML(writer, ["wdth", "wght", "opsz"])
        self.assertEqual(
            [
                "<tuple>",
                '<coord axis="wdth" min="0.25" value="0.375" max="0.5"/>',
                '<coord axis="wght" value="1.0"/>',
                '<coord axis="opsz" value="-0.75"/>',
                '<delta pt="0" x="9" y="8"/>',
                '<delta pt="2" x="7" y="6"/>',
                '<delta pt="3" x="0" y="0"/>',
                '<delta pt="4" x="-1" y="-2"/>',
                "</tuple>",
            ],
            TupleVariationTest.xml_lines(writer),
        )

    def test_toXML_allDeltasNone(self):
        writer = XMLWriter(BytesIO())
        axes = {"wght": (0.0, 1.0, 1.0)}
        g = TupleVariation(axes, [None] * 5)
        g.toXML(writer, ["wght", "wdth"])
        self.assertEqual(
            [
                "<tuple>",
                '<coord axis="wght" value="1.0"/>',
                "<!-- no deltas -->",
                "</tuple>",
            ],
            TupleVariationTest.xml_lines(writer),
        )

    def test_toXML_axes_floats(self):
        writer = XMLWriter(BytesIO())
        axes = {
            "wght": (0.0, 0.2999878, 0.7000122),
            "wdth": (0.0, 0.4000244, 0.4000244),
        }
        g = TupleVariation(axes, [None] * 5)
        g.toXML(writer, ["wght", "wdth"])
        self.assertEqual(
            [
                '<coord axis="wght" min="0.0" value="0.3" max="0.7"/>',
                '<coord axis="wdth" value="0.4"/>',
            ],
            TupleVariationTest.xml_lines(writer)[1:3],
        )

    def test_fromXML_badDeltaFormat(self):
        g = TupleVariation({}, [])
        with CapturingLogHandler(log, "WARNING") as captor:
            for name, attrs, content in parseXML('<delta a="1" b="2"/>'):
                g.fromXML(name, attrs, content)
        self.assertIn("bad delta format: a, b", [r.msg for r in captor.records])

    def test_fromXML_constants(self):
        g = TupleVariation({}, [None] * 4)
        for name, attrs, content in parseXML(
            '<coord axis="wdth" min="0.25" value="0.375" max="0.5"/>'
            '<coord axis="wght" value="1.0"/>'
            '<coord axis="opsz" value="-0.75"/>'
            '<delta cvt="1" value="42"/>'
            '<delta cvt="2" value="-23"/>'
        ):
            g.fromXML(name, attrs, content)
        self.assertEqual(AXES, g.axes)
        self.assertEqual([None, 42, -23, None], g.coordinates)

    def test_fromXML_points(self):
        g = TupleVariation({}, [None] * 4)
        for name, attrs, content in parseXML(
            '<coord axis="wdth" min="0.25" value="0.375" max="0.5"/>'
            '<coord axis="wght" value="1.0"/>'
            '<coord axis="opsz" value="-0.75"/>'
            '<delta pt="1" x="33" y="44"/>'
            '<delta pt="2" x="-2" y="170"/>'
        ):
            g.fromXML(name, attrs, content)
        self.assertEqual(AXES, g.axes)
        self.assertEqual([None, (33, 44), (-2, 170), None], g.coordinates)

    def test_fromXML_axes_floats(self):
        g = TupleVariation({}, [None] * 4)
        for name, attrs, content in parseXML(
            '<coord axis="wght" min="0.0" value="0.3" max="0.7"/>'
            '<coord axis="wdth" value="0.4"/>'
        ):
            g.fromXML(name, attrs, content)

        self.assertEqual(g.axes["wght"][0], 0)
        self.assertAlmostEqual(g.axes["wght"][1], 0.2999878)
        self.assertAlmostEqual(g.axes["wght"][2], 0.7000122)

        self.assertEqual(g.axes["wdth"][0], 0)
        self.assertAlmostEqual(g.axes["wdth"][1], 0.4000244)
        self.assertAlmostEqual(g.axes["wdth"][2], 0.4000244)

    def test_compile_sharedPeaks_nonIntermediate_sharedPoints(self):
        var = TupleVariation(
            {"wght": (0.0, 0.5, 0.5), "wdth": (0.0, 0.8, 0.8)}, [(7, 4), (8, 5), (9, 6)]
        )
        axisTags = ["wght", "wdth"]
        sharedPeakIndices = {var.compileCoord(axisTags): 0x77}
        tup, deltas = var.compile(axisTags, sharedPeakIndices, pointData=b"")
        # len(deltas)=8; flags=None; tupleIndex=0x77
        # embeddedPeaks=[]; intermediateCoord=[]
        self.assertEqual("00 08 00 77", hexencode(tup))
        self.assertEqual(
            "02 07 08 09 " "02 04 05 06",  # deltaX: [7, 8, 9]  # deltaY: [4, 5, 6]
            hexencode(deltas),
        )

    def test_compile_sharedPeaks_intermediate_sharedPoints(self):
        var = TupleVariation(
            {"wght": (0.3, 0.5, 0.7), "wdth": (0.1, 0.8, 0.9)}, [(7, 4), (8, 5), (9, 6)]
        )
        axisTags = ["wght", "wdth"]
        sharedPeakIndices = {var.compileCoord(axisTags): 0x77}
        tup, deltas = var.compile(axisTags, sharedPeakIndices, pointData=b"")
        # len(deltas)=8; flags=INTERMEDIATE_REGION; tupleIndex=0x77
        # embeddedPeak=[]; intermediateCoord=[(0.3, 0.1), (0.7, 0.9)]
        self.assertEqual("00 08 40 77 13 33 06 66 2C CD 39 9A", hexencode(tup))
        self.assertEqual(
            "02 07 08 09 " "02 04 05 06",  # deltaX: [7, 8, 9]  # deltaY: [4, 5, 6]
            hexencode(deltas),
        )

    def test_compile_sharedPeaks_nonIntermediate_privatePoints(self):
        var = TupleVariation(
            {"wght": (0.0, 0.5, 0.5), "wdth": (0.0, 0.8, 0.8)}, [(7, 4), (8, 5), (9, 6)]
        )
        axisTags = ["wght", "wdth"]
        sharedPeakIndices = {var.compileCoord(axisTags): 0x77}
        tup, deltas = var.compile(axisTags, sharedPeakIndices)
        # len(deltas)=9; flags=PRIVATE_POINT_NUMBERS; tupleIndex=0x77
        # embeddedPeak=[]; intermediateCoord=[]
        self.assertEqual("00 09 20 77", hexencode(tup))
        self.assertEqual(
            "00 "  # all points in glyph
            "02 07 08 09 "  # deltaX: [7, 8, 9]
            "02 04 05 06",  # deltaY: [4, 5, 6]
            hexencode(deltas),
        )

    def test_compile_sharedPeaks_intermediate_privatePoints(self):
        var = TupleVariation(
            {"wght": (0.0, 0.5, 1.0), "wdth": (0.0, 0.8, 1.0)}, [(7, 4), (8, 5), (9, 6)]
        )
        axisTags = ["wght", "wdth"]
        sharedPeakIndices = {var.compileCoord(axisTags): 0x77}
        tuple, deltas = var.compile(axisTags, sharedPeakIndices)
        # len(deltas)=9; flags=PRIVATE_POINT_NUMBERS; tupleIndex=0x77
        # embeddedPeak=[]; intermediateCoord=[(0.0, 0.0), (1.0, 1.0)]
        self.assertEqual("00 09 60 77 00 00 00 00 40 00 40 00", hexencode(tuple))
        self.assertEqual(
            "00 "  # all points in glyph
            "02 07 08 09 "  # deltaX: [7, 8, 9]
            "02 04 05 06",  # deltaY: [4, 5, 6]
            hexencode(deltas),
        )

    def test_compile_embeddedPeak_nonIntermediate_sharedPoints(self):
        var = TupleVariation(
            {"wght": (0.0, 0.5, 0.5), "wdth": (0.0, 0.8, 0.8)}, [(7, 4), (8, 5), (9, 6)]
        )
        tup, deltas = var.compile(axisTags=["wght", "wdth"], pointData=b"")
        # len(deltas)=8; flags=EMBEDDED_PEAK_TUPLE
        # embeddedPeak=[(0.5, 0.8)]; intermediateCoord=[]
        self.assertEqual("00 08 80 00 20 00 33 33", hexencode(tup))
        self.assertEqual(
            "02 07 08 09 " "02 04 05 06",  # deltaX: [7, 8, 9]  # deltaY: [4, 5, 6]
            hexencode(deltas),
        )

    def test_compile_embeddedPeak_nonIntermediate_sharedConstants(self):
        var = TupleVariation(
            {"wght": (0.0, 0.5, 0.5), "wdth": (0.0, 0.8, 0.8)}, [3, 1, 4]
        )
        tup, deltas = var.compile(axisTags=["wght", "wdth"], pointData=b"")
        # len(deltas)=4; flags=EMBEDDED_PEAK_TUPLE
        # embeddedPeak=[(0.5, 0.8)]; intermediateCoord=[]
        self.assertEqual("00 04 80 00 20 00 33 33", hexencode(tup))
        self.assertEqual("02 03 01 04", hexencode(deltas))  # delta: [3, 1, 4]

    def test_compile_embeddedPeak_intermediate_sharedPoints(self):
        var = TupleVariation(
            {"wght": (0.0, 0.5, 1.0), "wdth": (0.0, 0.8, 0.8)}, [(7, 4), (8, 5), (9, 6)]
        )
        tup, deltas = var.compile(axisTags=["wght", "wdth"], pointData=b"")
        # len(deltas)=8; flags=EMBEDDED_PEAK_TUPLE
        # embeddedPeak=[(0.5, 0.8)]; intermediateCoord=[(0.0, 0.0), (1.0, 0.8)]
        self.assertEqual(
            "00 08 C0 00 20 00 33 33 00 00 00 00 40 00 33 33", hexencode(tup)
        )
        self.assertEqual(
            "02 07 08 09 " "02 04 05 06",  # deltaX: [7, 8, 9]  # deltaY: [4, 5, 6]
            hexencode(deltas),
        )

    def test_compile_embeddedPeak_nonIntermediate_privatePoints(self):
        var = TupleVariation(
            {"wght": (0.0, 0.5, 0.5), "wdth": (0.0, 0.8, 0.8)}, [(7, 4), (8, 5), (9, 6)]
        )
        tup, deltas = var.compile(axisTags=["wght", "wdth"])
        # len(deltas)=9; flags=PRIVATE_POINT_NUMBERS|EMBEDDED_PEAK_TUPLE
        # embeddedPeak=[(0.5, 0.8)]; intermediateCoord=[]
        self.assertEqual("00 09 A0 00 20 00 33 33", hexencode(tup))
        self.assertEqual(
            "00 "  # all points in glyph
            "02 07 08 09 "  # deltaX: [7, 8, 9]
            "02 04 05 06",  # deltaY: [4, 5, 6]
            hexencode(deltas),
        )

    def test_compile_embeddedPeak_nonIntermediate_privateConstants(self):
        var = TupleVariation(
            {"wght": (0.0, 0.5, 0.5), "wdth": (0.0, 0.8, 0.8)}, [7, 8, 9]
        )
        tup, deltas = var.compile(axisTags=["wght", "wdth"])
        # len(deltas)=5; flags=PRIVATE_POINT_NUMBERS|EMBEDDED_PEAK_TUPLE
        # embeddedPeak=[(0.5, 0.8)]; intermediateCoord=[]
        self.assertEqual("00 05 A0 00 20 00 33 33", hexencode(tup))
        self.assertEqual(
            "00 " "02 07 08 09",  # all points in glyph  # delta: [7, 8, 9]
            hexencode(deltas),
        )

    def test_compile_embeddedPeak_intermediate_privatePoints(self):
        var = TupleVariation(
            {"wght": (0.4, 0.5, 0.6), "wdth": (0.7, 0.8, 0.9)}, [(7, 4), (8, 5), (9, 6)]
        )
        tup, deltas = var.compile(axisTags=["wght", "wdth"])
        # len(deltas)=9;
        # flags=PRIVATE_POINT_NUMBERS|INTERMEDIATE_REGION|EMBEDDED_PEAK_TUPLE
        # embeddedPeak=(0.5, 0.8); intermediateCoord=[(0.4, 0.7), (0.6, 0.9)]
        self.assertEqual(
            "00 09 E0 00 20 00 33 33 19 9A 2C CD 26 66 39 9A", hexencode(tup)
        )
        self.assertEqual(
            "00 "  # all points in glyph
            "02 07 08 09 "  # deltaX: [7, 8, 9]
            "02 04 05 06",  # deltaY: [4, 5, 6]
            hexencode(deltas),
        )

    def test_compile_embeddedPeak_intermediate_privateConstants(self):
        var = TupleVariation(
            {"wght": (0.4, 0.5, 0.6), "wdth": (0.7, 0.8, 0.9)}, [7, 8, 9]
        )
        tup, deltas = var.compile(axisTags=["wght", "wdth"])
        # len(deltas)=5;
        # flags=PRIVATE_POINT_NUMBERS|INTERMEDIATE_REGION|EMBEDDED_PEAK_TUPLE
        # embeddedPeak=(0.5, 0.8); intermediateCoord=[(0.4, 0.7), (0.6, 0.9)]
        self.assertEqual(
            "00 05 E0 00 20 00 33 33 19 9A 2C CD 26 66 39 9A", hexencode(tup)
        )
        self.assertEqual(
            "00 " "02 07 08 09",  # all points in glyph  # delta: [7, 8, 9]
            hexencode(deltas),
        )

    def test_compileCoord(self):
        var = TupleVariation(
            {"wght": (-1.0, -1.0, -1.0), "wdth": (0.4, 0.5, 0.6)}, [None] * 4
        )
        self.assertEqual("C0 00 20 00", hexencode(var.compileCoord(["wght", "wdth"])))
        self.assertEqual("20 00 C0 00", hexencode(var.compileCoord(["wdth", "wght"])))
        self.assertEqual("C0 00", hexencode(var.compileCoord(["wght"])))

    def test_compileIntermediateCoord(self):
        var = TupleVariation(
            {"wght": (-1.0, -1.0, 0.0), "wdth": (0.4, 0.5, 0.6)}, [None] * 4
        )
        self.assertEqual(
            "C0 00 19 9A 00 00 26 66",
            hexencode(var.compileIntermediateCoord(["wght", "wdth"])),
        )
        self.assertEqual(
            "19 9A C0 00 26 66 00 00",
            hexencode(var.compileIntermediateCoord(["wdth", "wght"])),
        )
        self.assertEqual(None, var.compileIntermediateCoord(["wght"]))
        self.assertEqual(
            "19 9A 26 66", hexencode(var.compileIntermediateCoord(["wdth"]))
        )

    def test_decompileCoord(self):
        decompileCoord = TupleVariation.decompileCoord_
        data = deHexStr("DE AD C0 00 20 00 DE AD")
        self.assertEqual(
            ({"wght": -1.0, "wdth": 0.5}, 6), decompileCoord(["wght", "wdth"], data, 2)
        )

    def test_decompileCoord_roundTrip(self):
        # Make sure we are not affected by https://github.com/fonttools/fonttools/issues/286
        data = deHexStr("7F B9 80 35")
        values, _ = TupleVariation.decompileCoord_(["wght", "wdth"], data, 0)
        axisValues = {axis: (val, val, val) for axis, val in values.items()}
        var = TupleVariation(axisValues, [None] * 4)
        self.assertEqual("7F B9 80 35", hexencode(var.compileCoord(["wght", "wdth"])))

    def test_compilePoints(self):
        compilePoints = lambda p: TupleVariation.compilePoints(set(p))
        self.assertEqual("00", hexencode(compilePoints(set())))  # all points in glyph
        self.assertEqual("01 00 07", hexencode(compilePoints([7])))
        self.assertEqual("01 80 FF FF", hexencode(compilePoints([65535])))
        self.assertEqual("02 01 09 06", hexencode(compilePoints([9, 15])))
        self.assertEqual(
            "06 05 07 01 F7 02 01 F2",
            hexencode(compilePoints([7, 8, 255, 257, 258, 500])),
        )
        self.assertEqual("03 01 07 01 80 01 EC", hexencode(compilePoints([7, 8, 500])))
        self.assertEqual(
            "04 01 07 01 81 BE E7 0C 0F",
            hexencode(compilePoints([7, 8, 0xBEEF, 0xCAFE])),
        )
        self.maxDiff = None
        self.assertEqual(
            "81 2C"
            + " 7F 00"  # 300 points (0x12c) in total
            + (127 * " 01")
            + " 7F"  # first run, contains 128 points: [0 .. 127]
            + (128 * " 01")
            + " 2B"  # second run, contains 128 points: [128 .. 255]
            + (44 * " 01"),  # third run, contains 44 points: [256 .. 299]
            hexencode(compilePoints(range(300))),
        )
        self.assertEqual(
            "81 8F"
            + " 7F 00"  # 399 points (0x18f) in total
            + (127 * " 01")
            + " 7F"  # first run, contains 128 points: [0 .. 127]
            + (128 * " 01")
            + " 7F"  # second run, contains 128 points: [128 .. 255]
            + (128 * " 01")
            + " 0E"  # third run, contains 128 points: [256 .. 383]
            + (15 * " 01"),  # fourth run, contains 15 points: [384 .. 398]
            hexencode(compilePoints(range(399))),
        )

    def test_decompilePoints(self):
        numPointsInGlyph = 65536
        allPoints = list(range(numPointsInGlyph))

        def decompilePoints(data, offset):
            points, offset = TupleVariation.decompilePoints_(
                numPointsInGlyph, deHexStr(data), offset, "gvar"
            )
            # Conversion to list needed for Python 3.
            return (list(points), offset)

        # all points in glyph
        self.assertEqual((allPoints, 1), decompilePoints("00", 0))
        # all points in glyph (in overly verbose encoding, not explicitly prohibited by spec)
        self.assertEqual((allPoints, 2), decompilePoints("80 00", 0))
        # 2 points; first run: [9, 9+6]
        self.assertEqual(([9, 15], 4), decompilePoints("02 01 09 06", 0))
        # 2 points; first run: [0xBEEF, 0xCAFE]. (0x0C0F = 0xCAFE - 0xBEEF)
        self.assertEqual(([0xBEEF, 0xCAFE], 6), decompilePoints("02 81 BE EF 0C 0F", 0))
        # 1 point; first run: [7]
        self.assertEqual(([7], 3), decompilePoints("01 00 07", 0))
        # 1 point; first run: [7] in overly verbose encoding
        self.assertEqual(([7], 4), decompilePoints("01 80 00 07", 0))
        # 1 point; first run: [65535]; requires words to be treated as unsigned numbers
        self.assertEqual(([65535], 4), decompilePoints("01 80 FF FF", 0))
        # 4 points; first run: [7, 8]; second run: [255, 257]. 257 is stored in delta-encoded bytes (0xFF + 2).
        self.assertEqual(
            ([7, 8, 263, 265], 7), decompilePoints("04 01 07 01 01 FF 02", 0)
        )
        # combination of all encodings, preceded and followed by 4 bytes of unused data
        data = "DE AD DE AD 04 01 07 01 81 BE E7 0C 0F DE AD DE AD"
        self.assertEqual(([7, 8, 0xBEEF, 0xCAFE], 13), decompilePoints(data, 4))
        self.assertSetEqual(
            set(range(300)),
            set(
                decompilePoints(
                    "81 2C"
                    + " 7F 00"  # 300 points (0x12c) in total
                    + (127 * " 01")
                    + " 7F"  # first run, contains 128 points: [0 .. 127]
                    + (128 * " 01")
                    + " AB"  # second run, contains 128 points: [128 .. 255]
                    + (44 * " 00 01"),  # third run, contains 44 points: [256 .. 299]
                    0,
                )[0]
            ),
        )
        self.assertSetEqual(
            set(range(399)),
            set(
                decompilePoints(
                    "81 8F"
                    + " 7F 00"  # 399 points (0x18f) in total
                    + (127 * " 01")
                    + " 7F"  # first run, contains 128 points: [0 .. 127]
                    + (128 * " 01")
                    + " FF"  # second run, contains 128 points: [128 .. 255]
                    + (128 * " 00 01")
                    + " 8E"  # third run, contains 128 points: [256 .. 383]
                    + (15 * " 00 01"),  # fourth run, contains 15 points: [384 .. 398]
                    0,
                )[0]
            ),
        )

    def test_decompilePoints_shouldAcceptBadPointNumbers(self):
        decompilePoints = TupleVariation.decompilePoints_
        # 2 points; first run: [3, 9].
        numPointsInGlyph = 8
        with CapturingLogHandler(log, "WARNING") as captor:
            decompilePoints(numPointsInGlyph, deHexStr("02 01 03 06"), 0, "cvar")
        self.assertIn(
            "point 9 out of range in 'cvar' table", [r.msg for r in captor.records]
        )

    def test_decompilePoints_roundTrip(self):
        numPointsInGlyph = (
            500  # greater than 255, so we also exercise code path for 16-bit encoding
        )
        compile = lambda points: TupleVariation.compilePoints(points)
        decompile = lambda data: set(
            TupleVariation.decompilePoints_(numPointsInGlyph, data, 0, "gvar")[0]
        )
        for i in range(50):
            points = set(random.sample(range(numPointsInGlyph), 30))
            self.assertSetEqual(
                points,
                decompile(compile(points)),
                "failed round-trip decompile/compilePoints; points=%s" % points,
            )
        allPoints = set(range(numPointsInGlyph))
        self.assertSetEqual(allPoints, decompile(compile(allPoints)))
        self.assertSetEqual(allPoints, decompile(compile(set())))

    def test_compileDeltas_points(self):
        var = TupleVariation({}, [None, (1, 0), (2, 0), None, (4, 0), None])
        # deltaX for points: [1, 2, 4]; deltaY for points: [0, 0, 0]
        self.assertEqual("02 01 02 04 82", hexencode(var.compileDeltas()))

    def test_compileDeltas_constants(self):
        var = TupleVariation({}, [None, 1, 2, None, 4, None])
        # delta for cvts: [1, 2, 4]
        self.assertEqual("02 01 02 04", hexencode(var.compileDeltas()))

    def test_compileDeltaValues(self):
        compileDeltaValues = lambda values: hexencode(
            TupleVariation.compileDeltaValues_(values)
        )
        # zeroes
        self.assertEqual("80", compileDeltaValues([0]))
        self.assertEqual("BF", compileDeltaValues([0] * 64))
        self.assertEqual("BF 80", compileDeltaValues([0] * 65))
        self.assertEqual("BF A3", compileDeltaValues([0] * 100))
        self.assertEqual("BF BF BF BF", compileDeltaValues([0] * 256))
        # bytes
        self.assertEqual("00 01", compileDeltaValues([1]))
        self.assertEqual(
            "06 01 02 03 7F 80 FF FE", compileDeltaValues([1, 2, 3, 127, -128, -1, -2])
        )
        self.assertEqual("3F" + (64 * " 7F"), compileDeltaValues([127] * 64))
        self.assertEqual("3F" + (64 * " 7F") + " 00 7F", compileDeltaValues([127] * 65))
        # words
        self.assertEqual("40 66 66", compileDeltaValues([0x6666]))
        self.assertEqual(
            "43 66 66 7F FF FF FF 80 00",
            compileDeltaValues([0x6666, 32767, -1, -32768]),
        )
        self.assertEqual("7F" + (64 * " 11 22"), compileDeltaValues([0x1122] * 64))
        self.assertEqual(
            "7F" + (64 * " 11 22") + " 40 11 22", compileDeltaValues([0x1122] * 65)
        )
        # bytes, zeroes, bytes: a single zero is more compact when encoded as part of the bytes run
        self.assertEqual(
            "04 7F 7F 00 7F 7F", compileDeltaValues([127, 127, 0, 127, 127])
        )
        self.assertEqual(
            "01 7F 7F 81 01 7F 7F", compileDeltaValues([127, 127, 0, 0, 127, 127])
        )
        self.assertEqual(
            "01 7F 7F 82 01 7F 7F", compileDeltaValues([127, 127, 0, 0, 0, 127, 127])
        )
        self.assertEqual(
            "01 7F 7F 83 01 7F 7F", compileDeltaValues([127, 127, 0, 0, 0, 0, 127, 127])
        )
        # bytes, zeroes
        self.assertEqual("01 01 00", compileDeltaValues([1, 0]))
        self.assertEqual("00 01 81", compileDeltaValues([1, 0, 0]))
        # words, bytes, words: a single byte is more compact when encoded as part of the words run
        self.assertEqual(
            "42 66 66 00 02 77 77", compileDeltaValues([0x6666, 2, 0x7777])
        )
        self.assertEqual(
            "40 66 66 01 02 02 40 77 77", compileDeltaValues([0x6666, 2, 2, 0x7777])
        )
        # words, zeroes, words
        self.assertEqual(
            "40 66 66 80 40 77 77", compileDeltaValues([0x6666, 0, 0x7777])
        )
        self.assertEqual(
            "40 66 66 81 40 77 77", compileDeltaValues([0x6666, 0, 0, 0x7777])
        )
        self.assertEqual(
            "40 66 66 82 40 77 77", compileDeltaValues([0x6666, 0, 0, 0, 0x7777])
        )
        # words, zeroes, bytes
        self.assertEqual(
            "40 66 66 80 02 01 02 03", compileDeltaValues([0x6666, 0, 1, 2, 3])
        )
        self.assertEqual(
            "40 66 66 81 02 01 02 03", compileDeltaValues([0x6666, 0, 0, 1, 2, 3])
        )
        self.assertEqual(
            "40 66 66 82 02 01 02 03", compileDeltaValues([0x6666, 0, 0, 0, 1, 2, 3])
        )
        # words, zeroes
        self.assertEqual("40 66 66 80", compileDeltaValues([0x6666, 0]))
        self.assertEqual("40 66 66 81", compileDeltaValues([0x6666, 0, 0]))

    def test_decompileDeltas(self):
        decompileDeltas = TupleVariation.decompileDeltas_
        # 83 = zero values (0x80), count = 4 (1 + 0x83 & 0x3F)
        self.assertEqual(([0, 0, 0, 0], 1), decompileDeltas(4, deHexStr("83"), 0))
        # 41 01 02 FF FF = signed 16-bit values (0x40), count = 2 (1 + 0x41 & 0x3F)
        self.assertEqual(
            ([258, -1], 5), decompileDeltas(2, deHexStr("41 01 02 FF FF"), 0)
        )
        # 01 81 07 = signed 8-bit values, count = 2 (1 + 0x01 & 0x3F)
        self.assertEqual(([-127, 7], 3), decompileDeltas(2, deHexStr("01 81 07"), 0))
        # combination of all three encodings, preceded and followed by 4 bytes of unused data
        data = deHexStr("DE AD BE EF 83 40 01 02 01 81 80 DE AD BE EF")
        self.assertEqual(
            ([0, 0, 0, 0, 258, -127, -128], 11), decompileDeltas(7, data, 4)
        )

    def test_decompileDeltas_roundTrip(self):
        numDeltas = 30
        compile = TupleVariation.compileDeltaValues_
        decompile = lambda data: TupleVariation.decompileDeltas_(numDeltas, data, 0)[0]
        for i in range(50):
            deltas = random.sample(range(-128, 127), 10)
            deltas.extend(random.sample(range(-32768, 32767), 10))
            deltas.extend([0] * 10)
            random.shuffle(deltas)
            self.assertListEqual(deltas, decompile(compile(deltas)))

    def test_compileSharedTuples(self):
        # Below, the peak coordinate {"wght": 1.0, "wdth": 0.8} appears
        # three times (most frequent sorted first); {"wght": 1.0, "wdth": 0.5}
        # and {"wght": 1.0, "wdth": 0.7} both appears two times (tie) and
        # are sorted alphanumerically to ensure determinism.
        # The peak coordinate {"wght": 1.0, "wdth": 0.9} appears only once
        # and is thus ignored.
        # Because the start and end of variation ranges is not encoded
        # into the shared pool, they should get ignored.
        deltas = [None] * 4
        variations = [
            TupleVariation({"wght": (1.0, 1.0, 1.0), "wdth": (0.5, 0.7, 1.0)}, deltas),
            TupleVariation({"wght": (1.0, 1.0, 1.0), "wdth": (0.2, 0.7, 1.0)}, deltas),
            TupleVariation({"wght": (1.0, 1.0, 1.0), "wdth": (0.2, 0.8, 1.0)}, deltas),
            TupleVariation({"wght": (1.0, 1.0, 1.0), "wdth": (0.3, 0.5, 1.0)}, deltas),
            TupleVariation({"wght": (1.0, 1.0, 1.0), "wdth": (0.3, 0.8, 1.0)}, deltas),
            TupleVariation({"wght": (1.0, 1.0, 1.0), "wdth": (0.3, 0.9, 1.0)}, deltas),
            TupleVariation({"wght": (1.0, 1.0, 1.0), "wdth": (0.4, 0.8, 1.0)}, deltas),
            TupleVariation({"wght": (1.0, 1.0, 1.0), "wdth": (0.5, 0.5, 1.0)}, deltas),
        ]
        result = compileSharedTuples(["wght", "wdth"], variations)
        self.assertEqual(
            [hexencode(c) for c in result],
            ["40 00 33 33", "40 00 20 00", "40 00 2C CD"],
        )

    def test_decompileSharedTuples_Skia(self):
        sharedTuples = decompileSharedTuples(
            axisTags=["wght", "wdth"],
            sharedTupleCount=8,
            data=SKIA_GVAR_SHARED_TUPLES_DATA,
            offset=0,
        )
        self.assertEqual(sharedTuples, SKIA_GVAR_SHARED_TUPLES)

    def test_decompileSharedTuples_empty(self):
        self.assertEqual(decompileSharedTuples(["wght"], 0, b"", 0), [])

    def test_compileTupleVariationStore_allVariationsRedundant(self):
        axes = {"wght": (0.3, 0.4, 0.5), "opsz": (0.7, 0.8, 0.9)}
        variations = [
            TupleVariation(axes, [None] * 4),
            TupleVariation(axes, [None] * 4),
            TupleVariation(axes, [None] * 4),
        ]
        self.assertEqual(
            compileTupleVariationStore(
                variations,
                pointCount=8,
                axisTags=["wght", "opsz"],
                sharedTupleIndices={},
            ),
            (0, b"", b""),
        )

    def test_compileTupleVariationStore_noVariations(self):
        self.assertEqual(
            compileTupleVariationStore(
                variations=[],
                pointCount=8,
                axisTags=["wght", "opsz"],
                sharedTupleIndices={},
            ),
            (0, b"", b""),
        )

    def test_compileTupleVariationStore_roundTrip_cvar(self):
        deltas = [1, 2, 3, 4]
        variations = [
            TupleVariation({"wght": (0.5, 1.0, 1.0), "wdth": (1.0, 1.0, 1.0)}, deltas),
            TupleVariation({"wght": (1.0, 1.0, 1.0), "wdth": (1.0, 1.0, 1.0)}, deltas),
        ]
        tupleVariationCount, tuples, data = compileTupleVariationStore(
            variations, pointCount=4, axisTags=["wght", "wdth"], sharedTupleIndices={}
        )
        self.assertEqual(
            decompileTupleVariationStore(
                "cvar",
                ["wght", "wdth"],
                tupleVariationCount,
                pointCount=4,
                sharedTuples={},
                data=(tuples + data),
                pos=0,
                dataPos=len(tuples),
            ),
            variations,
        )

    def test_compileTupleVariationStore_roundTrip_gvar(self):
        deltas = [(1, 1), (2, 2), (3, 3), (4, 4)]
        variations = [
            TupleVariation({"wght": (0.5, 1.0, 1.0), "wdth": (1.0, 1.0, 1.0)}, deltas),
            TupleVariation({"wght": (1.0, 1.0, 1.0), "wdth": (1.0, 1.0, 1.0)}, deltas),
        ]
        tupleVariationCount, tuples, data = compileTupleVariationStore(
            variations, pointCount=4, axisTags=["wght", "wdth"], sharedTupleIndices={}
        )
        self.assertEqual(
            decompileTupleVariationStore(
                "gvar",
                ["wght", "wdth"],
                tupleVariationCount,
                pointCount=4,
                sharedTuples={},
                data=(tuples + data),
                pos=0,
                dataPos=len(tuples),
            ),
            variations,
        )

    def test_decompileTupleVariationStore_Skia_I(self):
        tvar = decompileTupleVariationStore(
            tableTag="gvar",
            axisTags=["wght", "wdth"],
            tupleVariationCount=8,
            pointCount=18,
            sharedTuples=SKIA_GVAR_SHARED_TUPLES,
            data=SKIA_GVAR_I_DATA,
            pos=4,
            dataPos=36,
        )
        self.assertEqual(len(tvar), 8)
        self.assertEqual(tvar[0].axes, {"wght": (0.0, 1.0, 1.0)})
        self.assertEqual(
            " ".join(["%d,%d" % c for c in tvar[0].coordinates]),
            "257,0 -127,0 -128,58 -130,90 -130,62 -130,67 -130,32 -127,0 "
            "257,0 259,14 260,64 260,21 260,69 258,124 0,0 130,0 0,0 0,0",
        )

    def test_decompileTupleVariationStore_empty(self):
        self.assertEqual(
            decompileTupleVariationStore(
                tableTag="gvar",
                axisTags=[],
                tupleVariationCount=0,
                pointCount=5,
                sharedTuples=[],
                data=b"",
                pos=4,
                dataPos=4,
            ),
            [],
        )

    def test_getTupleSize(self):
        getTupleSize = TupleVariation.getTupleSize_
        numAxes = 3
        self.assertEqual(4 + numAxes * 2, getTupleSize(0x8042, numAxes))
        self.assertEqual(4 + numAxes * 4, getTupleSize(0x4077, numAxes))
        self.assertEqual(4, getTupleSize(0x2077, numAxes))
        self.assertEqual(4, getTupleSize(11, numAxes))

    def test_inferRegion(self):
        start, end = inferRegion_({"wght": -0.3, "wdth": 0.7})
        self.assertEqual(start, {"wght": -0.3, "wdth": 0.0})
        self.assertEqual(end, {"wght": 0.0, "wdth": 0.7})

    @staticmethod
    def xml_lines(writer):
        content = writer.file.getvalue().decode("utf-8")
        return [line.strip() for line in content.splitlines()][1:]

    def test_getCoordWidth(self):
        empty = TupleVariation({}, [])
        self.assertEqual(empty.getCoordWidth(), 0)

        empty = TupleVariation({}, [None])
        self.assertEqual(empty.getCoordWidth(), 0)

        gvarTuple = TupleVariation({}, [None, (0, 0)])
        self.assertEqual(gvarTuple.getCoordWidth(), 2)

        cvarTuple = TupleVariation({}, [None, 0])
        self.assertEqual(cvarTuple.getCoordWidth(), 1)

        cvarTuple.coordinates[1] *= 1.0
        self.assertEqual(cvarTuple.getCoordWidth(), 1)

        with self.assertRaises(TypeError):
            TupleVariation({}, [None, "a"]).getCoordWidth()

    def test_scaleDeltas_cvar(self):
        var = TupleVariation({}, [100, None])

        var.scaleDeltas(1.0)
        self.assertEqual(var.coordinates, [100, None])

        var.scaleDeltas(0.333)
        self.assertAlmostEqual(var.coordinates[0], 33.3)
        self.assertIsNone(var.coordinates[1])

        var.scaleDeltas(0.0)
        self.assertEqual(var.coordinates, [0, None])

    def test_scaleDeltas_gvar(self):
        var = TupleVariation({}, [(100, 200), None])

        var.scaleDeltas(1.0)
        self.assertEqual(var.coordinates, [(100, 200), None])

        var.scaleDeltas(0.333)
        self.assertAlmostEqual(var.coordinates[0][0], 33.3)
        self.assertAlmostEqual(var.coordinates[0][1], 66.6)
        self.assertIsNone(var.coordinates[1])

        var.scaleDeltas(0.0)
        self.assertEqual(var.coordinates, [(0, 0), None])

    def test_roundDeltas_cvar(self):
        var = TupleVariation({}, [55.5, None, 99.9])
        var.roundDeltas()
        self.assertEqual(var.coordinates, [56, None, 100])

    def test_roundDeltas_gvar(self):
        var = TupleVariation({}, [(55.5, 100.0), None, (99.9, 100.0)])
        var.roundDeltas()
        self.assertEqual(var.coordinates, [(56, 100), None, (100, 100)])

    def test_calcInferredDeltas(self):
        var = TupleVariation({}, [(0, 0), None, None, None])
        coords = [(1, 1), (1, 1), (1, 1), (1, 1)]

        var.calcInferredDeltas(coords, [])

        self.assertEqual(var.coordinates, [(0, 0), (0, 0), (0, 0), (0, 0)])

    def test_calcInferredDeltas_invalid(self):
        # cvar tuples can't have inferred deltas
        with self.assertRaises(TypeError):
            TupleVariation({}, [0]).calcInferredDeltas([], [])

        # origCoords must have same length as self.coordinates
        with self.assertRaises(ValueError):
            TupleVariation({}, [(0, 0), None]).calcInferredDeltas([], [])

        # at least 4 phantom points required
        with self.assertRaises(AssertionError):
            TupleVariation({}, [(0, 0), None]).calcInferredDeltas([(0, 0), (0, 0)], [])

        with self.assertRaises(AssertionError):
            TupleVariation({}, [(0, 0)] + [None] * 5).calcInferredDeltas(
                [(0, 0)] * 6, [1, 0]  # endPts not in increasing order
            )

    def test_optimize(self):
        var = TupleVariation({"wght": (0.0, 1.0, 1.0)}, [(0, 0)] * 5)

        var.optimize([(0, 0)] * 5, [0])

        self.assertEqual(var.coordinates, [None, None, None, None, None])

    def test_optimize_isComposite(self):
        # when a composite glyph's deltas are all (0, 0), we still want
        # to write out an entry in gvar, else macOS doesn't apply any
        # variations to the composite glyph (even if its individual components
        # do vary).
        # https://github.com/fonttools/fonttools/issues/1381
        var = TupleVariation({"wght": (0.0, 1.0, 1.0)}, [(0, 0)] * 5)
        var.optimize([(0, 0)] * 5, [0], isComposite=True)
        self.assertEqual(var.coordinates, [(0, 0)] * 5)

        # it takes more than 128 (0, 0) deltas before the optimized tuple with
        # (None) inferred deltas (except for the first) becomes smaller than
        # the un-optimized one that has all deltas explicitly set to (0, 0).
        var = TupleVariation({"wght": (0.0, 1.0, 1.0)}, [(0, 0)] * 129)
        var.optimize([(0, 0)] * 129, list(range(129 - 4)), isComposite=True)
        self.assertEqual(var.coordinates, [(0, 0)] + [None] * 128)

    def test_sum_deltas_gvar(self):
        var1 = TupleVariation(
            {},
            [
                (-20, 0),
                (-20, 0),
                (20, 0),
                (20, 0),
                (0, 0),
                (0, 0),
                (0, 0),
                (0, 0),
            ],
        )
        var2 = TupleVariation(
            {},
            [
                (-10, 0),
                (-10, 0),
                (10, 0),
                (10, 0),
                (0, 0),
                (20, 0),
                (0, 0),
                (0, 0),
            ],
        )

        var1 += var2

        self.assertEqual(
            var1.coordinates,
            [
                (-30, 0),
                (-30, 0),
                (30, 0),
                (30, 0),
                (0, 0),
                (20, 0),
                (0, 0),
                (0, 0),
            ],
        )

    def test_sum_deltas_gvar_invalid_length(self):
        var1 = TupleVariation({}, [(1, 2)])
        var2 = TupleVariation({}, [(1, 2), (3, 4)])

        with self.assertRaisesRegex(ValueError, "deltas with different lengths"):
            var1 += var2

    def test_sum_deltas_gvar_with_inferred_points(self):
        var1 = TupleVariation({}, [(1, 2), None])
        var2 = TupleVariation({}, [(2, 3), None])

        with self.assertRaisesRegex(ValueError, "deltas with inferred points"):
            var1 += var2

    def test_sum_deltas_cvar(self):
        axes = {"wght": (0.0, 1.0, 1.0)}
        var1 = TupleVariation(axes, [0, 1, None, None])
        var2 = TupleVariation(axes, [None, 2, None, 3])
        var3 = TupleVariation(axes, [None, None, None, 4])

        var1 += var2
        var1 += var3

        self.assertEqual(var1.coordinates, [0, 3, None, 7])


if __name__ == "__main__":
    import sys

    sys.exit(unittest.main())