We previously used the function
any as in
any::<u32>() to generate a
strategy for all
u32s. This function works with the trait
which QuickCheck users may be familiar with. In proptest, this trait
is already implemented for most owned types in the standard library,
but you can of course implement it for your own types.
In some cases, where it makes sense to define a canonical strategy, such as in
the JSON AST example, it is a good idea to implement
proptest-derive crate can
be used to automate implementing
Arbitrary in common cases.