Adding upstream version 1.2.2.upstream/1.2.2upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 610 insertions, 0 deletions

diff --git a/share/extensions/tests/test_inkex_svg.py b/share/extensions/tests/test_inkex_svg.py
new file mode 100644
index 0000000..09a9228
--- /dev/null
+++ b/share/extensions/tests/test_inkex_svg.py
@@ -0,0 +1,610 @@
+#!/usr/bin/env python
+# coding=utf-8
+#
+# Copyright (C) 2018 Martin Owens
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA.
+#
+"""
+Test the svg interface for inkscape extensions.
+"""
+from inkex.transforms import Vector2d
+from inkex import Guide
+from inkex.tester import TestCase
+from inkex.tester.svg import svg, svg_file, svg_unit_scaled
+from inkex import addNS
+
+
+class BasicSvgTest(TestCase):
+    """Basic svg tests"""
+
+    def test_svg_load(self):
+        """Test loading an svg with the right parser"""
+        self.assertEqual(type(svg()).__name__, "SvgDocumentElement")
+
+    def test_add_ns(self):
+        """Test adding a namespace to a tag"""
+        self.assertEqual(addNS("g", "svg"), "{http://www.w3.org/2000/svg}g")
+        self.assertEqual(
+            addNS("h", "inkscape"), "{http://www.inkscape.org/namespaces/inkscape}h"
+        )
+        self.assertEqual(
+            addNS("i", "sodipodi"),
+            "{http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd}i",
+        )
+        self.assertEqual(addNS("{p}j"), "{p}j")
+
+    def test_svg_ids(self):
+        """Test a list of ids from an svg document"""
+        self.assertEqual(svg('id="apples"').get_ids(), {"apples"})
+
+    def test_svg_new_id(self):
+        """Test generatign a new id for a given tag"""
+        doc = svg('id="apples"')
+        usedids = set(["apples"])
+        for prefix in ["apples"] * 3:
+            newid = doc.get_unique_id(prefix)
+            self.assertTrue(newid.startswith(prefix))
+            self.assertTrue(newid not in usedids)
+            usedids.add(newid)
+
+    def test_svg_select_id(self):
+        """Select an id from the document"""
+        doc = svg('id="bananas"')
+        doc.selection.set("bananas")
+        self.assertEqual(doc.selection["bananas"], doc)
+        self.assertEqual(doc.selection.first(), doc)
+        doc = svg('id="apples"')
+        doc.selection.set(doc.getElementById("apples"))
+        self.assertEqual(doc.selection["apples"], doc)
+        self.assertEqual(doc.selection.first(), doc)
+
+    def test_svg_by_class(self):
+        """Select elements by class"""
+        doc = svg_file(self.data_file("svg", "multilayered-test.svg"))
+        elems = doc.getElementsByClass("frog")
+        self.assertEqual(
+            [elem.get_id() for elem in elems],
+            ["path3902", "text3926", "path3900", "rect3898"],
+        )
+        elems = doc.getElementsByClass("apple")
+        self.assertEqual([elem.get_id() for elem in elems], ["text3926", "rect3898"])
+
+    def test_svg_by_href(self):
+        """Select element by xlink href"""
+        doc = svg_file(self.data_file("svg", "multilayered-test.svg"))
+        elem = doc.getElementsByHref("path3900")[0]
+        self.assertEqual(elem.TAG, "textPath")
+        self.assertEqual(elem.get_id(), "textPath3923")
+        elem = doc.getElementsByHref("path3904")[0]
+        self.assertEqual(elem.TAG, "textPath")
+        self.assertEqual(elem.get_id(), "textPath3906")
+        self.assertEqual(doc.getElementsByHref("not-an-id"), [])
+
+    def test_svg_by_url_link(self):
+        """Select element by urls in styles"""
+        doc = svg_file(self.data_file("svg", "markers.svg"))
+        elem = doc.getElementsByStyleUrl("Arrow1Lend")[0]
+        self.assertEqual(elem.get_id(), "dimension")
+        elem = doc.getElementsByStyleUrl("Arrow1Lstart")[0]
+        self.assertEqual(elem.get_id(), "dimension")
+        self.assertEqual(doc.getElementsByStyleUrl("not-an-id"), [])
+
+    def test_selected_bbox(self):
+        """Can we get a bounding box from the selected items"""
+        doc = svg_file(self.data_file("svg", "multilayered-test.svg"))
+        doc.selection.set("path3904", "path3902")
+        from inkex.transforms import BoundingBox
+
+        x, y, w, h = 199.544, 156.412, 377.489, 199.972  # from inkscape --query-all
+        expected_3904 = BoundingBox((x, x + w), (y, y + h))
+        x, y, w, h = 145.358, 478.373, 439.135, 419.142  # from inkscape --query-all
+        expected_3902 = BoundingBox((x, x + w), (y, y + h))
+        expected = list(expected_3902 + expected_3904)
+
+        for x, y in zip(expected, doc.selection.bounding_box()):
+            self.assertDeepAlmostEqual(tuple(x), tuple(y), delta=1e-3)
+
+    def test_svg_name(self):
+        """Can get the sodipodi name attribute"""
+        doc = svg_file(self.data_file("svg", "multilayered-test.svg"))
+        self.assertEqual(doc.name, "Nouveau document 1")
+
+    def test_svg_nameview(self):
+        """Can get the sodipodi nameview element"""
+        doc = svg()
+        self.assertEqual(doc.namedview.center.x, 0)
+        self.assertEqual(type(doc.namedview).__name__, "NamedView")
+
+    def test_svg_layers(self):
+        """Selected layer is selected"""
+        doc = svg_file(self.data_file("svg", "multilayered-test.svg"))
+        self.assertEqual(doc.get_current_layer().get("id"), "layer3")
+        doc = svg('id="empty"')
+        self.assertEqual(doc.get_current_layer(), doc)
+
+    def test_svg_center_position(self):
+        """SVG with namedview has a center position"""
+        doc = svg_file(self.data_file("svg", "multilayered-test.svg"))
+        self.assertTrue(doc.namedview.center.is_close((30.714286, 520.0)))
+        self.assertTrue(svg().namedview.center.is_close(Vector2d()))
+
+    def test_defs(self):
+        """Can get the defs from an svg file"""
+        doc = svg_file(self.data_file("svg", "markers.svg"))
+        self.assertEqual(len(doc.defs), 2)
+        doc = svg('id="empty"')
+        self.assertEqual(len(doc.defs), 0)
+
+    def test_scale(self):
+        """Scale of a document"""
+        doc = svg('id="empty" viewBox="0 0 100 100" width="200" height="200"')
+        self.assertEqual(doc.viewport_width, 200.0)
+        self.assertEqual(doc.get_viewbox()[2], 100.0)
+        self.assertEqual(doc.scale, 2.0)
+        doc = svg('id="empty" viewBox="0 0 0 0" width="200" height="200"')
+        self.assertEqual(doc.scale, 1.0)
+
+
+class NamedViewTest(TestCase):
+    """Tests for the named view functionality"""
+
+    def test_create_guide(self):
+        """Test creating guides"""
+        doc = svg_file(self.data_file("svg", "multilayered-test.svg"))
+        namedview = doc.namedview
+        self.assertEqual(len(namedview.get_guides()), 0)
+
+        namedview.add(Guide().move_to(50, 50, 45))
+        self.assertEqual(len(namedview.get_guides()), 1)
+        (guide,) = namedview.get_guides()
+        self.assertEqual(guide.get("position"), "50,50")
+        self.assertEqual(guide.get("orientation"), "0.707107,-0.707107")
+
+
+class GetDocumentWidthTest(TestCase):
+    """Tests for SvgDocumentElement.viewport_width and viewbox_width."""
+
+    def assert_svg_sizes(self, creation_string, viewport_width, viewbox_width):
+        """Check viewport and viewbox width"""
+        doc = svg(creation_string)
+        self.assertAlmostEqual(doc.viewbox_width, viewbox_width)
+        self.assertAlmostEqual(doc.viewport_width, viewport_width)
+
+    def test_no_dimensions(self):
+        """An empty width value should be default zero width"""
+        self.assert_svg_sizes("", 0, 0)
+
+    def test_empty_width(self):
+        """An empty width value should be the same as a missing width."""
+        self.assert_svg_sizes('width=""', 0, 0)
+
+    def test_empty_viewbox(self):
+        """An empty viewBox value should be the same as a missing viewBox."""
+        self.assert_svg_sizes('viewBox=""', 0, 0)
+
+    def test_empty_width_and_viewbox(self):
+        """Empty values for both should be the same as both missing."""
+        self.assert_svg_sizes('width="" viewBox=""', 0, 0)
+
+    def test_width_only(self):
+        """Test a fixed width"""
+        self.assert_svg_sizes('width="120mm"', 453.5433071, 453.5433071)
+
+    def test_width_and_viewbox(self):
+        """If both are present, width overrides viewBox."""
+        self.assert_svg_sizes('width="120mm" viewBox="0 0 22 99"', 453.5433071, 22)
+
+    def test_viewbox_only(self):
+        """IF only the viewBox is present"""
+        self.assert_svg_sizes('viewBox="0 0 22 99"', 22, 22)
+
+    def test_only_valid_viewbox(self):
+        """An empty width value should be the same as a missing width."""
+        self.assert_svg_sizes('width="" viewBox="0 0 22 99"', 22, 22)
+
+    def test_non_zero_viewbox_x(self):
+        """Demonstrate that a non-zero x value (viewbox[0]) does not affect the width value."""
+        self.assert_svg_sizes('width="" viewBox="5 7 22 99"', 22, 22)
+
+    def test_comma_separated_viewbox(self):
+        """Viewbox values can be separated by comma"""
+        self.assert_svg_sizes('width="" viewBox="5,7,22,99"', 22, 22)
+
+
+class GetDocumentHeightTest(TestCase):
+    """Tests for Effect.height."""
+
+    def assert_svg_sizes(self, creation_string, viewport_height, viewbox_height):
+        """Check viewport and viewbox height"""
+        doc = svg(creation_string)
+        self.assertAlmostEqual(doc.viewbox_height, viewbox_height)
+        self.assertAlmostEqual(doc.viewport_height, viewport_height)
+
+    def test_no_dimensions(self):
+        """Test height from blank svg"""
+        self.assert_svg_sizes("", 0, 0)
+
+    def test_empty_height(self):
+        """An empty height value should be the same as a missing height."""
+        self.assert_svg_sizes('height=""', 0, 0)
+
+    def test_empty_viewbox(self):
+        """An empty viewBox value should be the same as a missing viewBox."""
+        self.assert_svg_sizes('viewBox=""', 0, 0)
+
+    def test_empty_height_viewbox(self):
+        """Empty values for both should be the same as both missing."""
+        self.assert_svg_sizes('height="" viewBox=""', 0, 0)
+
+    def test_height_only(self):
+        """A simple height only in px"""
+        self.assert_svg_sizes('height="330px"', 330, 330)
+
+    def test_height_and_viewbox(self):
+        """If both are present, height overrides viewBox."""
+        self.assert_svg_sizes('height="330px" viewBox="0 0 22 99"', 330, 99)
+
+    def test_viewbox_only(self):
+        """Height from viewBox only"""
+        self.assert_svg_sizes('viewBox="0 0 22 99"', 99, 99)
+
+    def test_no_height_valid_viewbox(self):
+        """An empty height value should be the same as a missing height."""
+        self.assert_svg_sizes('height="" viewBox="0 0 22 99"', 99, 99)
+
+    def test_non_zero_viewbox_y(self):
+        """Demonstrate that a non-zero y value (viewbox[1]) does not affect the height value."""
+        self.assert_svg_sizes('height="" viewBox="5 7 22 99"', 99, 99)
+
+
+class GetDocumentUnitTest(TestCase):
+    """Tests for Effect.unit."""
+
+    def test_no_dimensions(self):
+        """Default units with no arguments"""
+        self.assertEqual(svg().unit, "px")
+
+    def test_width_only(self):
+        """ "Units from document width only"""
+        # TODO: Determine whether returning 'px' in this case is the
+        #     intended behavior.
+        self.assertEqual(svg('width="100m"').unit, "px")
+
+    def test_height_only(self):
+        """Units from document height only"""
+        # TODO: Determine whether returning 'px' in this case is the
+        #     intended behavior.
+        self.assertEqual(svg('height="100m"').unit, "px")
+
+    def test_viewbox_only(self):
+        """Test viewbox only document units"""
+        self.assertEqual(svg('viewBox="0 0 377 565"').unit, "px")
+
+    # Unit-ratio tests. Don't exhaustively test every unit conversion, just
+    # demonstrate that the logic works.
+
+    def test_width_and_viewbox_px(self):
+        """100mm is ~377px, so unit should be 'px'."""
+        self.assertEqual(svg('width="100mm" viewBox="0 0 377 565"').unit, "px")
+
+    def test_width_and_viewbox_in(self):
+        """100mm is ~3.94in, so unit should be 'in'."""
+        self.assertEqual(svg('width="100mm" viewBox="0 0 3.94 5.90"').unit, "in")
+
+    def test_unitless_width_and_viewbox(self):
+        """Unitless width should be treated as 'px'."""
+        # 3779px is ~1m, so unit should be 'm'.
+        self.assertEqual(svg('width="3779" viewBox="0 0 1 1.5"').unit, "m")
+
+    def test_height_with_viewbox(self):
+        """150mm is ~5.90in, so unit should be 'in', but height is ignored"""
+        # TODO: Determine whether returning 'px' in this case is the intended
+        #     behavior.
+        self.assertEqual(svg('height="150mm" viewBox="0 0 3.94 5.90"').unit, "px")
+
+    def test_height_width_and_viewbox(self):
+        """100mm is ~23.6pc, so unit should be 'pc'."""
+        doc = svg('width="100mm" height="150mm" viewBox="0 0 23.6 35.4"')
+        self.assertEqual(doc.unit, "pc")
+
+    def test_large_error_reverts_to_px(self):
+        """'px' instead of using the closest match 'pc'."""
+        # 100mm is ~23.6pc; 24.1 is ~2% off from that, so unit should fall back
+        self.assertEqual(svg('width="100mm" viewBox="0 0 24.1 35.4"').unit, "px")
+
+    # TODO: Demonstrate that unknown width units are treated as px while
+    #     determining the ratio.
+
+    # 100px fallback tests. Although that value is an arbitrary default, it's
+    # possible for users of inkex.Effect to depend on this behavior.
+    # NOTE: Do not treat the existence of these tests as a reason to preserve
+    # the 100px fallback logic.
+
+    def test_bad_width_number(self):
+        """Fallback test: Bad numbers default to 100"""
+        # First, demonstrate that 1in is 2.54cm, so unit should be 'cm'.
+        self.assertEqual(svg('width="1in" viewBox="0 0 2.54 1"').unit, "cm")
+
+        # Corrupt the width to contain an invalid number component; note that
+        # the units change to 'px'. This is because the corrupt number part is
+        # replaced with 100px, producing a width of "100px";
+        self.assertEqual(svg('width="ABCDin" viewBox="0 0 2.54 1"').unit, "px")
+
+    def test_bad_viewbox_entry(self):
+        """Fallback test: Bad viewBox default to 100"""
+        # First, demonstrate that 3779px is 1m, so unit should be 'm'.
+        self.assertEqual(svg('width="3779px" viewBox="0 0 1 1"').unit, "m")
+
+        # Corrupt the viewBox to include a non-float value; will default to 'px'
+        self.assertEqual(svg('width="3779px" viewBox="x 0 1 1"').unit, "px")
+
+
+class UserUnitTest(TestCase):
+    """Tests for methods that are based on the value of unit."""
+
+    def assertToUserUnit(
+        self, user_unit, test_value, expected
+    ):  # pylint: disable=invalid-name
+        """Checks a user unit and a test_value against the expected result"""
+        doc = svg_unit_scaled(user_unit)
+        self.assertEqual(doc.unit, user_unit, msg=svg)
+        self.assertAlmostEqual(doc.to_dimensionless(test_value), expected)
+
+    def assertToDocumentUnit(
+        self, user_unit, test_value, expected
+    ):  # pylint: disable=invalid-name
+        """Checks a user unit and a test_value against the expected result"""
+        doc = svg_unit_scaled(user_unit)
+        self.assertEqual(doc.unit, user_unit, msg=svg)
+        self.assertAlmostEqual(doc.unittouu(test_value), expected)
+
+    def assertFromUserUnit(
+        self, user_unit, value, unit, expected
+    ):  # pylint: disable=invalid-name
+        """Check converting from a user unity for the test_value"""
+        self.assertAlmostEqual(
+            svg_unit_scaled(user_unit).to_dimensional(value, unit), expected
+        )
+
+    def assertFromDocumentUnit(
+        self, user_unit, value, unit, expected
+    ):  # pylint: disable=invalid-name
+        """Check converting from a user unity for the test_value"""
+        self.assertAlmostEqual(
+            svg_unit_scaled(user_unit).uutounit(value, unit), expected
+        )
+
+    # Unit-ratio tests. Don't exhaustively test every unit conversion, just
+    # demonstrate that the logic works.
+
+    def test_unittouu_in_to_cm(self):
+        """1in is ~2.54cm"""
+        self.assertToDocumentUnit("cm", "1in", 2.54)
+
+    def test_unittouu_yd_to_m(self):
+        """1yd is ~0.9144m"""
+        self.assertToDocumentUnit("m", "1yd", 0.9144)
+
+    def test_unittouu_identity(self):
+        """If the input and output units are the same, the input and output
+        values should exactly be the same, too."""
+        self.assertToDocumentUnit("pc", "9.87654321pc", 9.87654321)
+
+    def test_unittouu_bad_input_number(self):
+        """Bad input number"""
+        self.assertToDocumentUnit("cm", "1in", 2.54)
+
+        # Corrupt the input to contain an invalid number component; note that
+        # the result changes to zero.
+        self.assertToDocumentUnit("cm", "ABCDin", 0)
+
+    def test_unittouu_bad_input_unit(self):
+        """Bad input unit"""
+        # Demonstrate that 1.0in passes through without change.
+        self.assertToDocumentUnit("in", "1.0in", 1.0)
+
+        # Corrupt the input to contain an invalid unit component; note that the
+        # result changes to 0.0, because corrupt parsing is zero px.
+        # it used to be the ratio between inches and pixels. This was
+        # because unittouu() treats unknown units as 'px'.
+        self.assertToDocumentUnit("in", "1.0ABCD", 0)
+
+    def test_to_dimensionless_in_to_cm(self):
+        """1in is 96px in a cm based document"""
+        self.assertToUserUnit("cm", "1in", 96.0)
+
+    def test_to_dimensionless_yd_to_m(self):
+        """1yd is 3456px"""
+        self.assertToUserUnit("m", "1yd", 3456.0)
+
+    def test_to_dimensionless_no_unit(self):
+        """If no unit is given, the value must not be changed in mm based documents."""
+        self.assertToUserUnit("mm", "9.87654321", 9.87654321)
+
+    def test_to_dimensionless_identity(self):
+        """User units are px. If a value is given in px, the value must not change"""
+        self.assertToUserUnit("px", "9.87654321px", 9.87654321)
+
+    def test_to_dimensionless_unitless_input(self):
+        """Passing a unitless value to unittouu() should treat the units as 'px'."""
+        self.assertToUserUnit("in", "96", 96)  # user unit = px
+
+    def test_to_dimensionless_empty_input(self):
+        """Passing an empty string to unittouu() should treat the value as zero."""
+        self.assertToUserUnit("in", "", 0)
+
+    def test_to_dimensionless_parsing(self):
+        """Test user unit parsing forms"""
+        for value in (
+            "100pc",
+            "100  pc",
+            "   100pc",
+            "100pc  ",
+            "+100pc",
+            "100.0pc",
+            "100.0e0pc",
+            "10.0e1pc",
+            "10.0e+1pc",
+            "1000.0e-1pc",
+            ".1e+3pc",
+            "+.1e+3pc",
+        ):
+            # 100pc is ~3.937in
+            self.assertToUserUnit("px", value, 1600)
+
+    def test_to_dimensionless_bad_input_number(self):
+        """Bad input number"""
+        self.assertToUserUnit("cm", "1in", 96.0)
+        # Demonstrate that 1in is ~96px, also in a "cm based" document.
+
+        # Corrupt the input to contain an invalid number component; note that
+        # the result changes to zero.
+        self.assertToUserUnit("cm", "ABCDin", 0)
+
+    def test_to_dimensionless_bad_input_unit(self):
+        """Bad input unit"""
+        # Demonstrate that 1.0px passes through without change.
+        self.assertToUserUnit("mm", "1.0px", 1.0)
+
+        # Corrupt the input to contain an invalid unit component; note that the
+        # result changes to 0.0, because corrupt parsing is zero px.
+        # it used to be the ratio between inches and pixels. This was
+        # because to_dimensionless() treats unknown units as 'px'.
+        self.assertToUserUnit("mm", "1.0ABCD", 0)
+
+    # Unit-ratio tests. Don't exhaustively test every unit conversion, just
+    # demonstrate that the logic works.
+
+    def test_to_dimensional_cm_to_in(self):
+        """Convert 1 user unit (px) to 'cm' in a in-based document"""
+        self.assertFromUserUnit("in", 1, "cm", 2.54 / 96)  # 1in is ~2.54cm
+
+    def test_to_dimensional_m_to_yd(self):
+        """Convert 1 user unit (px) to 'm' in a yd-based document"""
+        self.assertFromUserUnit("yd", 1, "m", 1 / 100 * 2.54 / 96)
+
+    def test_to_dimensional_identity(self):
+        """If the input unit is px, output value should be identical"""
+        self.assertFromUserUnit("pc", 9.87654321, "px", 9.87654321)
+
+    def test_to_dimensional_unknown_unit(self):
+        """Demonstrate that passing an unknown unit string to uutounit()"""
+        self.assertEqual(svg_unit_scaled("in").to_dimensional(1, "px"), 1)
+
+    def test_uutounit_cm_to_in(self):
+        """Convert 1 user unit ('in') to 'cm'."""
+        self.assertFromDocumentUnit("in", 1, "cm", 2.54)  # 1in is ~2.54cm
+
+    def test_uutounit_m_to_yd(self):
+        """Convert 1 user unit ('yd') to 'm'."""
+        self.assertFromDocumentUnit("yd", 1, "m", 0.9144)  # 1yd is ~0.9144m
+
+    def test_uutounit_unknown_unit(self):
+        """Demonstrate that passing an unknown unit string to uutounit()"""
+        self.assertEqual(svg_unit_scaled("in").uutounit(1, "px"), 96.0)
+
+    def test_adddocumentunit_common(self):
+        """Test common add_unit results"""
+        # For valid float inputs, the output should be the input with the user unit appended.
+        doc = svg_unit_scaled("pt")
+        cases = (
+            # Input, expected output
+            (100, "100pt"),
+            ("100", "100pt"),
+            ("+100", "100pt"),
+            ("-100", "-100pt"),
+            ("100.0", "100pt"),
+            ("100.0e0", "100pt"),
+            ("10.0e1", "100pt"),
+            ("10.0e+1", "100pt"),
+            ("1000.0e-1", "100pt"),
+            (".1e+3", "100pt"),
+            ("+.1e+3", "100pt"),
+            ("   100", "100pt"),
+            ("100   ", "100pt"),
+            ("  100   ", "100pt"),
+        )
+        for input_value, expected in cases:
+            self.assertEqual(doc.add_unit(input_value), expected)
+
+    def test_adddocumentunit_non_float(self):
+        """Strings that are invalid floats should pass through unchanged."""
+        doc = svg_unit_scaled("pt")
+        inputs = (
+            "",
+            "ABCD",
+            ".",
+            "   ",
+        )
+        for value in inputs:
+            self.assertEqual(doc.add_unit(value), "")
+
+    def test_scales(self):
+        svg1 = svg('width="793.70081" height="1122.5197" viewBox="0 0 105 148.5"')
+        self.assertAlmostEqual(svg1.scale, 7.559055, places=5)
+        self.assertAlmostEqual(svg1.inkscape_scale, 7.559055, places=5)
+
+        svg1 = svg('width="210mm" height="297mm" viewBox="0 0 105 148.5"')
+        self.assertAlmostEqual(svg1.scale, 7.559055, places=5)
+        self.assertEqual(svg1.inkscape_scale, 2)
+
+        svg1 = svg('viewBox="0 0 105 148.5"')
+        self.assertEqual(svg1.scale, 1)
+        self.assertEqual(svg1.inkscape_scale, 1)
+
+
+class ViewportUnitTestCase(TestCase):
+    def assertFromVPUnit(
+        self, width_unit, test_value, unit, expected
+    ):  # pylint: disable=invalid-name
+        """Checks a viewport unit and a test_value against the expected result"""
+        doc = svg_unit_scaled(width_unit)
+        self.assertEqual(doc.unit, width_unit, msg=svg)
+        self.assertAlmostEqual(doc.viewport_to_unit(test_value, unit), expected)
+
+    def assertToVPUnit(
+        self, user_unit, value, unit, expected
+    ):  # pylint: disable=invalid-name
+        """Check converting from a user unity for the test_value"""
+        self.assertAlmostEqual(
+            svg_unit_scaled(user_unit).unit_to_viewport(value, unit), expected
+        )
+
+    def test_unittovp(self):
+        """1in is ~2.54cm"""
+        self.assertToVPUnit("px", "1in", "px", 96)
+        self.assertToVPUnit("px", "1", "px", 1)
+
+        # 1 in = 96 px = 96 * 96 px/in / 2.54 cm/in on the viewport
+        self.assertToVPUnit(
+            "cm",
+            "1in",
+            "px",
+            96 * 96 / 2.54,
+        )
+        self.assertToVPUnit(
+            "cm",
+            "1in",
+            "in",
+            96 / 2.54,
+        )
+        self.assertToVPUnit("mm", "4", "mm", 4)
+        self.assertToVPUnit("mm", "4", "px", 4 * 96 / 25.4)
+
+    def test_vptounit(self):
+        self.assertFromVPUnit("mm", "1m", "px", 1000)
+        self.assertFromVPUnit("mm", "4mm", "px", 4)
+        self.assertFromVPUnit("mm", "4mm", "mm", 4 * 25.4 / 96)