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#![cfg(feature = "derive")]
// Various structs/fields that we are deriving `Arbitrary` for aren't actually
// used except to exercise the derive.
#![allow(dead_code)]
use arbitrary::*;
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")
}
#[derive(Copy, Clone, Debug, Eq, PartialEq, Arbitrary)]
pub struct Rgb {
pub r: u8,
pub g: u8,
pub b: u8,
}
#[test]
fn struct_with_named_fields() {
let rgb: Rgb = arbitrary_from(&[4, 5, 6]);
assert_eq!(rgb.r, 4);
assert_eq!(rgb.g, 5);
assert_eq!(rgb.b, 6);
assert_eq!((3, Some(3)), <Rgb as Arbitrary>::size_hint(0));
}
#[derive(Copy, Clone, Debug, Arbitrary)]
struct MyTupleStruct(u8, bool);
#[test]
fn tuple_struct() {
let s: MyTupleStruct = arbitrary_from(&[43, 42]);
assert_eq!(s.0, 43);
assert_eq!(s.1, false);
let s: MyTupleStruct = arbitrary_from(&[42, 43]);
assert_eq!(s.0, 42);
assert_eq!(s.1, true);
assert_eq!((2, Some(2)), <MyTupleStruct as Arbitrary>::size_hint(0));
}
#[derive(Clone, Debug, Arbitrary)]
struct EndingInVec(u8, bool, u32, Vec<u16>);
#[derive(Clone, Debug, Arbitrary)]
struct EndingInString(u8, bool, u32, String);
#[test]
fn test_take_rest() {
let bytes = [1, 1, 1, 2, 3, 4, 5, 6, 7, 8];
let s1 = EndingInVec::arbitrary_take_rest(Unstructured::new(&bytes)).unwrap();
let s2 = EndingInString::arbitrary_take_rest(Unstructured::new(&bytes)).unwrap();
assert_eq!(s1.0, 1);
assert_eq!(s2.0, 1);
assert_eq!(s1.1, true);
assert_eq!(s2.1, true);
assert_eq!(s1.2, 0x4030201);
assert_eq!(s2.2, 0x4030201);
assert_eq!(s1.3, vec![0x605, 0x807]);
assert_eq!(s2.3, "\x05\x06\x07\x08");
}
#[derive(Copy, Clone, Debug, Arbitrary)]
enum MyEnum {
Unit,
Tuple(u8, u16),
Struct { a: u32, b: (bool, u64) },
}
#[test]
fn derive_enum() {
let mut raw = vec![
// The choice of which enum variant takes 4 bytes.
1, 2, 3, 4,
// And then we need up to 13 bytes for creating `MyEnum::Struct`, the
// largest variant.
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
];
let mut saw_unit = false;
let mut saw_tuple = false;
let mut saw_struct = false;
for i in 0..=255 {
// Choose different variants each iteration.
for el in &mut raw[..4] {
*el = i;
}
let e: MyEnum = arbitrary_from(&raw);
match e {
MyEnum::Unit => {
saw_unit = true;
}
MyEnum::Tuple(a, b) => {
saw_tuple = true;
assert_eq!(a, arbitrary_from(&raw[4..5]));
assert_eq!(b, arbitrary_from(&raw[5..]));
}
MyEnum::Struct { a, b } => {
saw_struct = true;
assert_eq!(a, arbitrary_from(&raw[4..8]));
assert_eq!(b, arbitrary_from(&raw[8..]));
}
}
}
assert!(saw_unit);
assert!(saw_tuple);
assert!(saw_struct);
assert_eq!((4, Some(17)), <MyEnum as Arbitrary>::size_hint(0));
}
#[derive(Arbitrary, Debug)]
enum RecursiveTree {
Leaf,
Node {
left: Box<RecursiveTree>,
right: Box<RecursiveTree>,
},
}
#[test]
fn recursive() {
let raw = vec![1, 2, 3, 4, 5, 6, 7, 8, 9];
let _rec: RecursiveTree = arbitrary_from(&raw);
let (lower, upper) = <RecursiveTree as Arbitrary>::size_hint(0);
assert_eq!(lower, 4, "need a u32 for the discriminant at minimum");
assert!(
upper.is_none(),
"potentially infinitely recursive, so no upper bound"
);
}
#[derive(Arbitrary, Debug)]
struct Generic<T> {
inner: T,
}
#[test]
fn generics() {
let raw = vec![1, 2, 3, 4, 5, 6, 7, 8, 9];
let gen: Generic<bool> = arbitrary_from(&raw);
assert!(gen.inner);
let (lower, upper) = <Generic<u32> as Arbitrary>::size_hint(0);
assert_eq!(lower, 4);
assert_eq!(upper, Some(4));
}
#[derive(Arbitrary, Debug)]
struct OneLifetime<'a> {
alpha: &'a str,
}
#[test]
fn one_lifetime() {
// Last byte is used for length
let raw: Vec<u8> = vec![97, 98, 99, 100, 3];
let lifetime: OneLifetime = arbitrary_from(&raw);
assert_eq!("abc", lifetime.alpha);
let (lower, upper) = <OneLifetime as Arbitrary>::size_hint(0);
assert_eq!(lower, 0);
assert_eq!(upper, None);
}
#[derive(Arbitrary, Debug)]
struct TwoLifetimes<'a, 'b> {
alpha: &'a str,
beta: &'b str,
}
#[test]
fn two_lifetimes() {
// Last byte is used for length
let raw: Vec<u8> = vec![97, 98, 99, 100, 101, 102, 103, 3];
let lifetime: TwoLifetimes = arbitrary_from(&raw);
assert_eq!("abc", lifetime.alpha);
assert_eq!("def", lifetime.beta);
let (lower, upper) = <TwoLifetimes as Arbitrary>::size_hint(0);
assert_eq!(lower, 0);
assert_eq!(upper, None);
}
#[test]
fn recursive_and_empty_input() {
// None of the following derives should result in a stack overflow. See
#[derive(Debug, Arbitrary)]
enum Nat {
Succ(Box<Nat>),
Zero,
}
let _ = Nat::arbitrary(&mut Unstructured::new(&[]));
#[derive(Debug, Arbitrary)]
enum Nat2 {
Zero,
Succ(Box<Nat2>),
}
let _ = Nat2::arbitrary(&mut Unstructured::new(&[]));
#[derive(Debug, Arbitrary)]
struct Nat3 {
f: Option<Box<Nat3>>,
}
let _ = Nat3::arbitrary(&mut Unstructured::new(&[]));
#[derive(Debug, Arbitrary)]
struct Nat4(Option<Box<Nat4>>);
let _ = Nat4::arbitrary(&mut Unstructured::new(&[]));
#[derive(Debug, Arbitrary)]
enum Nat5 {
Zero,
Succ { f: Box<Nat5> },
}
let _ = Nat5::arbitrary(&mut Unstructured::new(&[]));
}
#[test]
fn test_field_attributes() {
// A type that DOES NOT implement Arbitrary
#[derive(Debug)]
struct Weight(u8);
#[derive(Debug, Arbitrary)]
struct Parcel {
#[arbitrary(with = arbitrary_weight)]
weight: Weight,
#[arbitrary(default)]
width: u8,
#[arbitrary(value = 2 + 2)]
length: u8,
height: u8,
#[arbitrary(with = |u: &mut Unstructured| u.int_in_range(0..=100))]
price: u8,
}
fn arbitrary_weight(u: &mut Unstructured) -> arbitrary::Result<Weight> {
u.int_in_range(45..=56).map(Weight)
}
let parcel: Parcel = arbitrary_from(&[6, 199, 17]);
// 45 + 6 = 51
assert_eq!(parcel.weight.0, 51);
// u8::default()
assert_eq!(parcel.width, 0);
// 2 + 2 = 4
assert_eq!(parcel.length, 4);
// 199 is the 2nd byte used by arbitrary
assert_eq!(parcel.height, 199);
// 17 is the 3rd byte used by arbitrary
assert_eq!(parcel.price, 17);
}