As developers of libraries implementing interval arithmetic, we faced the
same difficulties when it comes to testing our libraries. What must be tested?
How can we devise relevant test cases for unit testing? How can we ensure a
high (and possibly 100%) test coverage? Before considering these questions, we
briefly recall the main features of interval arithmetic and of the IEEE
1788-2015 standard for interval arithmetic. After listing the different aspects
that, in our opinion, must be tested, we contribute a first step towards
offering a test suite for an interval arithmetic library. First we define a
format that enables the exchange of test cases, so that they can be read and
tried easily. Then we offer a first set of test cases, for a selected set of
mathematical functions. Next, we examine how the Julia interval arithmetic
library, IntervalArithmetic.jl, actually performs to these tests. As this is an
ongoing work, we list extra tests that we deem important to perform.Comment: 2 figure