def test_none_vs_numeric(self):
diff = _make_difference(None, 6) # For None vs non-zero,
self.assertEqual(diff, Deviation(-6, 6)) # difference is calculated
# as 0 - other.
diff = _make_difference(None, 0) # For None vs zero,
self.assertEqual(diff, Deviation(None, 0)) # difference remains None.
def test_same(self):
"""The _make_difference() function returns differences for
objects that are KNOWN TO BE DIFFERENT--it does not test
for differences itself.
"""
diff = _make_difference('a', 'a')
self.assertEqual(diff, Invalid('a', 'a'))
diff = _make_difference(None, None)
self.assertEqual(diff, Invalid(None, None))
def test_show_expected(self):
"""If requirement is common it should be omitted from Invalid
difference (but not from Deviation differences).
"""
diff = _make_difference('a', 6, show_expected=True)
self.assertEqual(diff, Invalid('a', expected=6))
diff = _make_difference('a', 6, show_expected=False)
self.assertEqual(diff, Invalid('a'))
diff = _make_difference(NOVALUE, 6, show_expected=False)
self.assertEqual(diff, Deviation(-6, 6))
def test_novalue_comparisons(self):
diff = _make_difference('a', NOVALUE)
self.assertEqual(diff, Extra('a'))
diff = _make_difference(NOVALUE, 'b')
self.assertEqual(diff, Missing('b'))
# For numeric comparisons, NOVALUE behaves like None.
diff = _make_difference(5, NOVALUE)
self.assertEqual(diff, Deviation(+5, None))
diff = _make_difference(0, NOVALUE)
self.assertEqual(diff, Deviation(0, None))
diff = _make_difference(NOVALUE, 6)
self.assertEqual(diff, Deviation(-6, 6)) # <- Asymmetric behavior
# (see None vs numeric)!
diff = _make_difference(NOVALUE, 0)
self.assertEqual(diff, Deviation(None, 0))
def test_object_vs_object(self):
"""Non-numeric comparisons return Invalid type."""
diff = _make_difference('a', 'b')
self.assertEqual(diff, Invalid('a', 'b'))
diff = _make_difference(5, 'b')
self.assertEqual(diff, Invalid(5, 'b'))
diff = _make_difference('a', 6)
self.assertEqual(diff, Invalid('a', 6))
diff = _make_difference(float('nan'), 6)
self.assertEqual(diff, Invalid(float('nan'), 6))
diff = _make_difference(5, float('nan'))
self.assertEqual(diff, Invalid(5, float('nan')))
fn = lambda x: True
diff = _make_difference('a', fn)
self.assertEqual(diff, Invalid('a', fn))
regex = re.compile('^test$')
diff = _make_difference('a', regex)
self.assertEqual(diff, Invalid('a', re.compile('^test$')))
def test_numeric_vs_none(self):
diff = _make_difference(5, None)
self.assertEqual(diff, Deviation(+5, None))
diff = _make_difference(0, None)
self.assertEqual(diff, Deviation(+0, None))
def test_numeric_vs_numeric(self):
diff = _make_difference(5, 6)
self.assertEqual(diff, Deviation(-1, 6))
