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ToleranceMatcher is unable to compare NaN doubles

See original GitHub issue

Code:

Double.NaN shouldBe Double.NaN

Expected result: no errors, NaN == NaN

Actual result: java.lang.AssertionError: NaN should be equal to NaN

So, we have to have separate comparison for NaN values. JUnit does this - code below does not throw any exceptions:

assertEquals(Double.NaN, Double.NaN)

Issue Analytics

State:
Created 6 years ago
Comments:15 (14 by maintainers)

Top GitHub Comments

1reaction

LeoColmancommented, Jan 8, 2019

Yes, you must either filter or handle NaN and Infinities.

The point in generators is that you’re saying “My program can handle absolutely any Double!” and both NaN and Infinities are valid doubles to be passed.

What we can discuss is if we should support out-of-the-box a matcher for “Numeric, non-corner-case Doubles”

0reactions

breandancommented, Jan 8, 2019

Done, please use #530 to discuss custom generators for restricted subsets of floating point values.

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