Floating point equality comparison fails in tests

[AMDmi3]

FreeBSD 13.0, elementpath 2.5.0, some tests fail:

============================= test session starts ==============================
platform freebsd13 -- Python 3.8.13, pytest-7.1.1, pluggy-0.13.1
rootdir: /work/usr/ports/textproc/py-elementpath/work-py38/elementpath-2.5.0
collected 1953 items

tests/test_datatypes.py ................................................ [  2%]
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tests/test_exceptions.py ..                                              [  5%]
tests/test_helpers.py ......                                             [  6%]
tests/test_namespaces.py ....                                            [  6%]
tests/test_package.py ..                                                 [  6%]
tests/test_regex.py .................................................... [  9%]
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tests/test_schema_context.py sssssss                                     [  9%]
tests/test_schema_proxy.py ssssssssssssssssssssssssssssssssssssss        [ 11%]
tests/test_selectors.py ....                                             [ 11%]
tests/test_tdop_parser.py ...................                            [ 12%]
tests/test_typing.py s                                                   [ 13%]
tests/test_xpath1_parser.py ............................................ [ 15%]
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tests/test_xpath2_constructors.py ...................................... [ 22%]
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tests/test_xpath2_functions.py .............s........................... [ 26%]
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tests/test_xpath2_parser.py ..............s............................. [ 35%]
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tests/test_xpath30.py ....................s............................. [ 49%]
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tests/test_xpath_context.py ....................                         [ 96%]
tests/test_xpath_nodes.py .....................                          [ 97%]
tests/test_xpath_token.py .....................ss.........ss..s....s.... [ 99%]
...                                                                      [100%]

=================================== FAILURES ===================================
___________________ XPath30ParserTest.test_exp_math_function ___________________

self = <tests.test_xpath30.XPath30ParserTest testMethod=test_exp_math_function>

    def test_exp_math_function(self):
        token = self.parser.parse('math:exp(())')
        self.assertIsNone(token.evaluate())
        self.assertEqual(self.parser.parse('math:exp(0)').evaluate(), 1.0)
>       self.assertEqual(self.parser.parse('math:exp(1)').evaluate(), 2.718281828459045)
E       AssertionError: 2.7182818284590455 != 2.718281828459045

tests/test_xpath30.py:133: AssertionError
_________________ LxmlXPath3ParserTest.test_exp_math_function __________________

self = <tests.test_xpath30.LxmlXPath3ParserTest testMethod=test_exp_math_function>

    def test_exp_math_function(self):
        token = self.parser.parse('math:exp(())')
        self.assertIsNone(token.evaluate())
        self.assertEqual(self.parser.parse('math:exp(0)').evaluate(), 1.0)
>       self.assertEqual(self.parser.parse('math:exp(1)').evaluate(), 2.718281828459045)
E       AssertionError: 2.7182818284590455 != 2.718281828459045

tests/test_xpath30.py:133: AssertionError
___________________ XPath31ParserTest.test_exp_math_function ___________________

self = <tests.test_xpath30.XPath31ParserTest testMethod=test_exp_math_function>

    def test_exp_math_function(self):
        token = self.parser.parse('math:exp(())')
        self.assertIsNone(token.evaluate())
        self.assertEqual(self.parser.parse('math:exp(0)').evaluate(), 1.0)
>       self.assertEqual(self.parser.parse('math:exp(1)').evaluate(), 2.718281828459045)
E       AssertionError: 2.7182818284590455 != 2.718281828459045

tests/test_xpath30.py:133: AssertionError
_________________ LxmlXPath31ParserTest.test_exp_math_function _________________

self = <tests.test_xpath30.LxmlXPath31ParserTest testMethod=test_exp_math_function>

    def test_exp_math_function(self):
        token = self.parser.parse('math:exp(())')
        self.assertIsNone(token.evaluate())
        self.assertEqual(self.parser.parse('math:exp(0)').evaluate(), 1.0)
>       self.assertEqual(self.parser.parse('math:exp(1)').evaluate(), 2.718281828459045)
E       AssertionError: 2.7182818284590455 != 2.718281828459045

tests/test_xpath30.py:133: AssertionError
=========================== short test summary info ============================
FAILED tests/test_xpath30.py::XPath30ParserTest::test_exp_math_function - Ass...
FAILED tests/test_xpath30.py::LxmlXPath3ParserTest::test_exp_math_function - ...
FAILED tests/test_xpath30.py::XPath31ParserTest::test_exp_math_function - Ass...
FAILED tests/test_xpath30.py::LxmlXPath31ParserTest::test_exp_math_function
============ 4 failed, 1873 passed, 76 skipped in 82.21s (0:01:22) =============

It is well known that floating point values cannot be tested for equality, these should probably be replaced with epsilon-comparison, such as https://docs.pytest.org/en/4.6.x/reference.html#pytest-approx

[brunato]

Hi,
yes, it's my superficiality on some tests.
I will use math.isclose() for fixing faulty tests, that is already used on others.

Thanks

[brunato]

Used assertAlmostEqual() of the unittest library.
Please check v2.5.1 with FreeBSD and, if the tests are good, close this issue.

[AMDmi3]

Fix confirmed