Source code for pint.testsuite.test_definitions

from pint.converters import OffsetConverter, ScaleConverter
from pint.definitions import (
    AliasDefinition,
    Definition,
    DimensionDefinition,
    PrefixDefinition,
    UnitDefinition,
)
from pint.errors import DefinitionSyntaxError
from pint.testsuite import BaseTestCase
from pint.util import UnitsContainer


[docs]class TestDefinition(BaseTestCase): def test_invalid(self): with self.assertRaises(DefinitionSyntaxError): Definition.from_string("x = [time] * meter") with self.assertRaises(DefinitionSyntaxError): Definition.from_string("[x] = [time] * meter") def test_prefix_definition(self): self.assertRaises(ValueError, Definition.from_string, "m- = 1e-3 k") for definition in ("m- = 1e-3", "m- = 10**-3", "m- = 0.001"): x = Definition.from_string(definition) self.assertIsInstance(x, PrefixDefinition) self.assertEqual(x.name, "m") self.assertEqual(x.aliases, ()) self.assertEqual(x.converter.to_reference(1000), 1) self.assertEqual(x.converter.from_reference(0.001), 1) self.assertEqual(str(x), "m") x = Definition.from_string("kilo- = 1e-3 = k-") self.assertIsInstance(x, PrefixDefinition) self.assertEqual(x.name, "kilo") self.assertEqual(x.aliases, ()) self.assertEqual(x.symbol, "k") self.assertEqual(x.converter.to_reference(1000), 1) self.assertEqual(x.converter.from_reference(0.001), 1) x = Definition.from_string("kilo- = 1e-3 = k- = anotherk-") self.assertIsInstance(x, PrefixDefinition) self.assertEqual(x.name, "kilo") self.assertEqual(x.aliases, ("anotherk",)) self.assertEqual(x.symbol, "k") self.assertEqual(x.converter.to_reference(1000), 1) self.assertEqual(x.converter.from_reference(0.001), 1) def test_baseunit_definition(self): x = Definition.from_string("meter = [length]") self.assertIsInstance(x, UnitDefinition) self.assertTrue(x.is_base) self.assertEqual(x.reference, UnitsContainer({"[length]": 1})) def test_unit_definition(self): x = Definition.from_string("coulomb = ampere * second") self.assertIsInstance(x, UnitDefinition) self.assertFalse(x.is_base) self.assertIsInstance(x.converter, ScaleConverter) self.assertEqual(x.converter.scale, 1) self.assertEqual(x.reference, UnitsContainer(ampere=1, second=1)) x = Definition.from_string("faraday = 96485.3399 * coulomb") self.assertIsInstance(x, UnitDefinition) self.assertFalse(x.is_base) self.assertIsInstance(x.converter, ScaleConverter) self.assertEqual(x.converter.scale, 96485.3399) self.assertEqual(x.reference, UnitsContainer(coulomb=1)) x = Definition.from_string("degF = 9 / 5 * kelvin; offset: 255.372222") self.assertIsInstance(x, UnitDefinition) self.assertFalse(x.is_base) self.assertIsInstance(x.converter, OffsetConverter) self.assertEqual(x.converter.scale, 9 / 5) self.assertEqual(x.converter.offset, 255.372222) self.assertEqual(x.reference, UnitsContainer(kelvin=1)) x = Definition.from_string( "turn = 6.28 * radian = _ = revolution = = cycle = _" ) self.assertIsInstance(x, UnitDefinition) self.assertEqual(x.name, "turn") self.assertEqual(x.aliases, ("revolution", "cycle")) self.assertEqual(x.symbol, "turn") self.assertFalse(x.is_base) self.assertIsInstance(x.converter, ScaleConverter) self.assertEqual(x.converter.scale, 6.28) self.assertEqual(x.reference, UnitsContainer(radian=1)) self.assertRaises( ValueError, Definition.from_string, "degF = 9 / 5 * kelvin; offset: 255.372222 bla", ) def test_dimension_definition(self): x = DimensionDefinition("[time]", "", (), converter="") self.assertTrue(x.is_base) self.assertEqual(x.name, "[time]") x = Definition.from_string("[speed] = [length]/[time]") self.assertIsInstance(x, DimensionDefinition) self.assertEqual(x.reference, UnitsContainer({"[length]": 1, "[time]": -1})) def test_alias_definition(self): x = Definition.from_string("@alias meter = metro = metr") self.assertIsInstance(x, AliasDefinition) self.assertEqual(x.name, "meter") self.assertEqual(x.aliases, ("metro", "metr"))