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#![cfg(feature = "derive")]
use arbitrary::{Arbitrary, Unstructured};
fn arbitrary_from<'a, T: Arbitrary<'a>>(input: &'a [u8]) -> T {
let mut buf = Unstructured::new(input);
T::arbitrary(&mut buf).expect("can create arbitrary instance OK")
}
/// This wrapper trait *implies* `Arbitrary`, but the compiler isn't smart enough to work that out
/// so when using this wrapper we *must* opt-out of the auto-generated `T: Arbitrary` bounds.
pub trait WrapperTrait: for<'a> Arbitrary<'a> {}
impl WrapperTrait for u32 {}
#[derive(Arbitrary)]
#[arbitrary(bound = "T: WrapperTrait")]
struct GenericSingleBound<T: WrapperTrait> {
t: T,
}
#[test]
fn single_bound() {
let v: GenericSingleBound<u32> = arbitrary_from(&[0, 0, 0, 0]);
assert_eq!(v.t, 0);
}
#[derive(Arbitrary)]
#[arbitrary(bound = "T: WrapperTrait, U: WrapperTrait")]
struct GenericMultipleBoundsSingleAttribute<T: WrapperTrait, U: WrapperTrait> {
t: T,
u: U,
}
#[test]
fn multiple_bounds_single_attribute() {
let v: GenericMultipleBoundsSingleAttribute<u32, u32> =
arbitrary_from(&[1, 0, 0, 0, 2, 0, 0, 0]);
assert_eq!(v.t, 1);
assert_eq!(v.u, 2);
}
#[derive(Arbitrary)]
#[arbitrary(bound = "T: WrapperTrait")]
#[arbitrary(bound = "U: Default")]
struct GenericMultipleArbitraryAttributes<T: WrapperTrait, U: Default> {
t: T,
#[arbitrary(default)]
u: U,
}
#[test]
fn multiple_arbitrary_attributes() {
let v: GenericMultipleArbitraryAttributes<u32, u32> = arbitrary_from(&[1, 0, 0, 0]);
assert_eq!(v.t, 1);
assert_eq!(v.u, 0);
}
#[derive(Arbitrary)]
#[arbitrary(bound = "T: WrapperTrait", bound = "U: Default")]
struct GenericMultipleBoundAttributes<T: WrapperTrait, U: Default> {
t: T,
#[arbitrary(default)]
u: U,
}
#[test]
fn multiple_bound_attributes() {
let v: GenericMultipleBoundAttributes<u32, u32> = arbitrary_from(&[1, 0, 0, 0]);
assert_eq!(v.t, 1);
assert_eq!(v.u, 0);
}
#[derive(Arbitrary)]
#[arbitrary(bound = "T: WrapperTrait", bound = "U: Default")]
#[arbitrary(bound = "V: WrapperTrait, W: Default")]
struct GenericMultipleArbitraryAndBoundAttributes<
T: WrapperTrait,
U: Default,
V: WrapperTrait,
W: Default,
> {
t: T,
#[arbitrary(default)]
u: U,
v: V,
#[arbitrary(default)]
w: W,
}
#[test]
fn multiple_arbitrary_and_bound_attributes() {
let v: GenericMultipleArbitraryAndBoundAttributes<u32, u32, u32, u32> =
arbitrary_from(&[1, 0, 0, 0, 2, 0, 0, 0]);
assert_eq!(v.t, 1);
assert_eq!(v.u, 0);
assert_eq!(v.v, 2);
assert_eq!(v.w, 0);
}
#[derive(Arbitrary)]
#[arbitrary(bound = "T: Default")]
struct GenericDefault<T: Default> {
#[arbitrary(default)]
x: T,
}
#[test]
fn default_bound() {
// We can write a generic func without any `Arbitrary` bound.
fn generic_default<T: Default>() -> GenericDefault<T> {
arbitrary_from(&[])
}
assert_eq!(generic_default::<u64>().x, 0);
assert_eq!(generic_default::<String>().x, String::new());
assert_eq!(generic_default::<Vec<u8>>().x, Vec::new());
}
#[derive(Arbitrary)]
#[arbitrary()]
struct EmptyArbitraryAttribute {
t: u32,
}
#[test]
fn empty_arbitrary_attribute() {
let v: EmptyArbitraryAttribute = arbitrary_from(&[1, 0, 0, 0]);
assert_eq!(v.t, 1);
}
#[derive(Arbitrary)]
#[arbitrary(bound = "")]
struct EmptyBoundAttribute {
t: u32,
}
#[test]
fn empty_bound_attribute() {
let v: EmptyBoundAttribute = arbitrary_from(&[1, 0, 0, 0]);
assert_eq!(v.t, 1);
}