Hamkrest provides a function, called describe, that generates readable representations of values for inclusion in assertion failure messages and the descriptions of matchers.
For example:
describe(10)
>>> 10
describe(listOf("a","b","c"))
>>> ["a", "b", "c"]
describe(null)
>>> null
The describe function generates reasonable representations of primitive types, null, Strings, Pairs,
Triples and Collections, and falls back to calling toString when it has no specialised representation for
a value.
If the built-in representation is not suitable for your types, you can plug new representations into the describe function by registering a JVM service of type com.natpryce.hamkrest.ValueDescription.
The ValueDescription service interface implements a single method, also called describe, which maps a value either to
a String representation, or to null if the service cannot generate a representation for the value. When a
ValueDescription service returns null, Hamkrest will pass the value to other registered ValueDescription services and,
if no services can describe the value, generate a description using the default rules described above.
Tip: You can define ValueDescription services in each module of your project, meaning they can use internal features of your modules to generate representations.