org.mpxj.junit

Class SumTest

java.lang.Object

org.mpxj.junit.SumTest

public class SumTest
extends Object

Tests for NumberHelper.sumAsDouble, which sums costs. This uses the JDK's compensated summation, whose last bits are not the same on every JDK: both DoubleStream.sum and DoubleSummaryStatistics add the compensation on Java 8 and subtract it on later versions. So these tests pin the behaviour callers rely on, and the agreement between the two JDK routes, rather than hard coding sums which would only hold on one runtime.

Constructor Summary

Constructors

Constructor and Description
SumTest()

Method Summary

Modifier and Type	Method and Description
void	exactValuesSumExactly() Test that exactly representable values sum exactly, and that no values sum to zero.
void	matchesDoubleStreamSum() Test that summing matches the stream the callers previously used, whichever JDK this is.
void	mixedNumberTypesAreSummed() Test that mixed number types are summed by their double value.
void	nullValuesCountAsZero() Test that a null value counts as zero, and that a zero result is a positive zero.
void	sameSignedInfinitiesDoNotBecomeNaN() Test that same signed infinities sum to that infinity rather than NaN, which is what the simple sum held alongside the compensated one is for.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SumTest

public SumTest()

Method Detail

matchesDoubleStreamSum

@Test
public void matchesDoubleStreamSum()

Test that summing matches the stream the callers previously used, whichever JDK this is.

exactValuesSumExactly

@Test
public void exactValuesSumExactly()

Test that exactly representable values sum exactly, and that no values sum to zero.

nullValuesCountAsZero

@Test
public void nullValuesCountAsZero()

Test that a null value counts as zero, and that a zero result is a positive zero. Double.equals compares bits, so a negative zero would not be equal to the zero callers expect.

sameSignedInfinitiesDoNotBecomeNaN

@Test
public void sameSignedInfinitiesDoNotBecomeNaN()

Test that same signed infinities sum to that infinity rather than NaN, which is what the simple sum held alongside the compensated one is for.

mixedNumberTypesAreSummed

@Test
public void mixedNumberTypesAreSummed()

Test that mixed number types are summed by their double value.