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// Copyright © 2019 The Rust Fuzz Project Developers.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//! The `Arbitrary` trait crate.
//!
//! This trait provides an [`Arbitrary`](./trait.Arbitrary.html) trait to
//! produce well-typed, structured values, from raw, byte buffers. It is
//! generally intended to be used with fuzzers like AFL or libFuzzer. See the
//! [`Arbitrary`](./trait.Arbitrary.html) trait's documentation for details on
//! automatically deriving, implementing, and/or using the trait.
#![deny(bad_style)]
#![deny(missing_docs)]
#![deny(future_incompatible)]
#![deny(nonstandard_style)]
#![deny(rust_2018_compatibility)]
#![deny(rust_2018_idioms)]
#![deny(unused)]
#[cfg(feature = "derive_arbitrary")]
pub use derive_arbitrary::*;
mod error;
pub use error::*;
pub mod unstructured;
#[doc(inline)]
pub use unstructured::Unstructured;
pub mod size_hint;
use core::array;
use core::cell::{Cell, RefCell, UnsafeCell};
use core::iter;
use core::mem;
use core::num::{NonZeroI128, NonZeroI16, NonZeroI32, NonZeroI64, NonZeroI8, NonZeroIsize};
use core::num::{NonZeroU128, NonZeroU16, NonZeroU32, NonZeroU64, NonZeroU8, NonZeroUsize};
use core::ops::{Range, RangeBounds, RangeFrom, RangeInclusive, RangeTo, RangeToInclusive};
use core::str;
use core::time::Duration;
use std::borrow::{Cow, ToOwned};
use std::collections::{BTreeMap, BTreeSet, BinaryHeap, HashMap, HashSet, LinkedList, VecDeque};
use std::ffi::{CString, OsString};
use std::hash::BuildHasher;
use std::net::{Ipv4Addr, Ipv6Addr};
use std::ops::Bound;
use std::path::PathBuf;
use std::rc::Rc;
use std::sync::atomic::{AtomicBool, AtomicIsize, AtomicUsize};
use std::sync::{Arc, Mutex};
/// Generate arbitrary structured values from raw, unstructured data.
///
/// The `Arbitrary` trait allows you to generate valid structured values, like
/// `HashMap`s, or ASTs, or `MyTomlConfig`, or any other data structure from
/// raw, unstructured bytes provided by a fuzzer.
///
/// # Deriving `Arbitrary`
///
/// Automatically deriving the `Arbitrary` trait is the recommended way to
/// implement `Arbitrary` for your types.
///
/// Using the custom derive requires that you enable the `"derive"` cargo
/// feature in your `Cargo.toml`:
///
/// ```toml
/// [dependencies]
/// arbitrary = { version = "1", features = ["derive"] }
/// ```
///
/// Then, you add the `#[derive(Arbitrary)]` annotation to your `struct` or
/// `enum` type definition:
///
/// ```
/// # #[cfg(feature = "derive")] mod foo {
/// use arbitrary::Arbitrary;
/// use std::collections::HashSet;
///
/// #[derive(Arbitrary)]
/// pub struct AddressBook {
/// friends: HashSet<Friend>,
/// }
///
/// #[derive(Arbitrary, Hash, Eq, PartialEq)]
/// pub enum Friend {
/// Buddy { name: String },
/// Pal { age: usize },
/// }
/// # }
/// ```
///
/// Every member of the `struct` or `enum` must also implement `Arbitrary`.
///
/// # Implementing `Arbitrary` By Hand
///
/// Implementing `Arbitrary` mostly involves nested calls to other `Arbitrary`
/// arbitrary implementations for each of your `struct` or `enum`'s members. But
/// sometimes you need some amount of raw data, or you need to generate a
/// variably-sized collection type, or something of that sort. The
/// [`Unstructured`][crate::Unstructured] type helps you with these tasks.
///
/// ```
/// # #[cfg(feature = "derive")] mod foo {
/// # pub struct MyCollection<T> { _t: std::marker::PhantomData<T> }
/// # impl<T> MyCollection<T> {
/// # pub fn new() -> Self { MyCollection { _t: std::marker::PhantomData } }
/// # pub fn insert(&mut self, element: T) {}
/// # }
/// use arbitrary::{Arbitrary, Result, Unstructured};
///
/// impl<'a, T> Arbitrary<'a> for MyCollection<T>
/// where
/// T: Arbitrary<'a>,
/// {
/// fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
/// // Get an iterator of arbitrary `T`s.
/// let iter = u.arbitrary_iter::<T>()?;
///
/// // And then create a collection!
/// let mut my_collection = MyCollection::new();
/// for elem_result in iter {
/// let elem = elem_result?;
/// my_collection.insert(elem);
/// }
///
/// Ok(my_collection)
/// }
/// }
/// # }
/// ```
pub trait Arbitrary<'a>: Sized {
/// Generate an arbitrary value of `Self` from the given unstructured data.
///
/// Calling `Arbitrary::arbitrary` requires that you have some raw data,
/// perhaps given to you by a fuzzer like AFL or libFuzzer. You wrap this
/// raw data in an `Unstructured`, and then you can call `<MyType as
/// Arbitrary>::arbitrary` to construct an arbitrary instance of `MyType`
/// from that unstructured data.
///
/// Implementations may return an error if there is not enough data to
/// construct a full instance of `Self`, or they may fill out the rest of
/// `Self` with dummy values. Using dummy values when the underlying data is
/// exhausted can help avoid accidentally "defeating" some of the fuzzer's
/// mutations to the underlying byte stream that might otherwise lead to
/// interesting runtime behavior or new code coverage if only we had just a
/// few more bytes. However, it also requires that implementations for
/// recursive types (e.g. `struct Foo(Option<Box<Foo>>)`) avoid infinite
/// recursion when the underlying data is exhausted.
///
/// ```
/// # #[cfg(feature = "derive")] fn foo() {
/// use arbitrary::{Arbitrary, Unstructured};
///
/// #[derive(Arbitrary)]
/// pub struct MyType {
/// // ...
/// }
///
/// // Get the raw data from the fuzzer or wherever else.
/// # let get_raw_data_from_fuzzer = || &[];
/// let raw_data: &[u8] = get_raw_data_from_fuzzer();
///
/// // Wrap that raw data in an `Unstructured`.
/// let mut unstructured = Unstructured::new(raw_data);
///
/// // Generate an arbitrary instance of `MyType` and do stuff with it.
/// if let Ok(value) = MyType::arbitrary(&mut unstructured) {
/// # let do_stuff = |_| {};
/// do_stuff(value);
/// }
/// # }
/// ```
///
/// See also the documentation for [`Unstructured`][crate::Unstructured].
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self>;
/// Generate an arbitrary value of `Self` from the entirety of the given
/// unstructured data.
///
/// This is similar to Arbitrary::arbitrary, however it assumes that it is
/// the last consumer of the given data, and is thus able to consume it all
/// if it needs. See also the documentation for
/// [`Unstructured`][crate::Unstructured].
fn arbitrary_take_rest(mut u: Unstructured<'a>) -> Result<Self> {
Self::arbitrary(&mut u)
}
/// Get a size hint for how many bytes out of an `Unstructured` this type
/// needs to construct itself.
///
/// This is useful for determining how many elements we should insert when
/// creating an arbitrary collection.
///
/// The return value is similar to
/// [`Iterator::size_hint`][iterator-size-hint]: it returns a tuple where
/// the first element is a lower bound on the number of bytes required, and
/// the second element is an optional upper bound.
///
/// The default implementation return `(0, None)` which is correct for any
/// type, but not ultimately that useful. Using `#[derive(Arbitrary)]` will
/// create a better implementation. If you are writing an `Arbitrary`
/// implementation by hand, and your type can be part of a dynamically sized
/// collection (such as `Vec`), you are strongly encouraged to override this
/// default with a better implementation. The
/// [`size_hint`][crate::size_hint] module will help with this task.
///
/// ## Invariant
///
/// It must be possible to construct every possible output using only inputs
/// of lengths bounded by these parameters. This applies to both
/// [`Arbitrary::arbitrary`] and [`Arbitrary::arbitrary_take_rest`].
///
/// This is trivially true for `(0, None)`. To restrict this further, it
/// must be proven that all inputs that are now excluded produced redundant
/// outputs which are still possible to produce using the reduced input
/// space.
///
/// ## The `depth` Parameter
///
/// If you 100% know that the type you are implementing `Arbitrary` for is
/// not a recursive type, or your implementation is not transitively calling
/// any other `size_hint` methods, you can ignore the `depth` parameter.
/// Note that if you are implementing `Arbitrary` for a generic type, you
/// cannot guarantee the lack of type recursion!
///
/// Otherwise, you need to use
/// [`arbitrary::size_hint::recursion_guard(depth)`][crate::size_hint::recursion_guard]
/// to prevent potential infinite recursion when calculating size hints for
/// potentially recursive types:
///
/// ```
/// use arbitrary::{Arbitrary, Unstructured, size_hint};
///
/// // This can potentially be a recursive type if `L` or `R` contain
/// // something like `Box<Option<MyEither<L, R>>>`!
/// enum MyEither<L, R> {
/// Left(L),
/// Right(R),
/// }
///
/// impl<'a, L, R> Arbitrary<'a> for MyEither<L, R>
/// where
/// L: Arbitrary<'a>,
/// R: Arbitrary<'a>,
/// {
/// fn arbitrary(u: &mut Unstructured) -> arbitrary::Result<Self> {
/// // ...
/// # unimplemented!()
/// }
///
/// fn size_hint(depth: usize) -> (usize, Option<usize>) {
/// // Protect against potential infinite recursion with
/// // `recursion_guard`.
/// size_hint::recursion_guard(depth, |depth| {
/// // If we aren't too deep, then `recursion_guard` calls
/// // this closure, which implements the natural size hint.
/// // Don't forget to use the new `depth` in all nested
/// // `size_hint` calls! We recommend shadowing the
/// // parameter, like what is done here, so that you can't
/// // accidentally use the wrong depth.
/// size_hint::or(
/// <L as Arbitrary>::size_hint(depth),
/// <R as Arbitrary>::size_hint(depth),
/// )
/// })
/// }
/// }
/// ```
///
/// [iterator-size-hint]: https://doc.rust-lang.org/stable/std/iter/trait.Iterator.html#method.size_hint
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
let _ = depth;
(0, None)
}
}
impl<'a> Arbitrary<'a> for () {
fn arbitrary(_: &mut Unstructured<'a>) -> Result<Self> {
Ok(())
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, Some(0))
}
}
impl<'a> Arbitrary<'a> for bool {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Ok(<u8 as Arbitrary<'a>>::arbitrary(u)? & 1 == 1)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<u8 as Arbitrary<'a>>::size_hint(depth)
}
}
macro_rules! impl_arbitrary_for_integers {
( $( $ty:ty: $unsigned:ty; )* ) => {
$(
impl<'a> Arbitrary<'a> for $ty {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
let mut buf = [0; mem::size_of::<$ty>()];
u.fill_buffer(&mut buf)?;
let mut x: $unsigned = 0;
for i in 0..mem::size_of::<$ty>() {
x |= buf[i] as $unsigned << (i * 8);
}
Ok(x as $ty)
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
let n = mem::size_of::<$ty>();
(n, Some(n))
}
}
)*
}
}
impl_arbitrary_for_integers! {
u8: u8;
u16: u16;
u32: u32;
u64: u64;
u128: u128;
usize: usize;
i8: u8;
i16: u16;
i32: u32;
i64: u64;
i128: u128;
isize: usize;
}
macro_rules! impl_arbitrary_for_floats {
( $( $ty:ident : $unsigned:ty; )* ) => {
$(
impl<'a> Arbitrary<'a> for $ty {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Ok(Self::from_bits(<$unsigned as Arbitrary<'a>>::arbitrary(u)?))
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<$unsigned as Arbitrary<'a>>::size_hint(depth)
}
}
)*
}
}
impl_arbitrary_for_floats! {
f32: u32;
f64: u64;
}
impl<'a> Arbitrary<'a> for char {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
use std::char;
// The highest unicode code point is 0x11_FFFF
const CHAR_END: u32 = 0x11_0000;
// The size of the surrogate blocks
const SURROGATES_START: u32 = 0xD800;
let mut c = <u32 as Arbitrary<'a>>::arbitrary(u)? % CHAR_END;
if let Some(c) = char::from_u32(c) {
Ok(c)
} else {
// We found a surrogate, wrap and try again
c -= SURROGATES_START;
Ok(char::from_u32(c)
.expect("Generated character should be valid! This is a bug in arbitrary-rs"))
}
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<u32 as Arbitrary<'a>>::size_hint(depth)
}
}
impl<'a> Arbitrary<'a> for AtomicBool {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Self::new)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<bool as Arbitrary<'a>>::size_hint(depth)
}
}
impl<'a> Arbitrary<'a> for AtomicIsize {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Self::new)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<isize as Arbitrary<'a>>::size_hint(depth)
}
}
impl<'a> Arbitrary<'a> for AtomicUsize {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Self::new)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<usize as Arbitrary<'a>>::size_hint(depth)
}
}
macro_rules! impl_range {
(
$range:ty,
$value_closure:expr,
$value_ty:ty,
$fun:ident($fun_closure:expr),
$size_hint_closure:expr
) => {
impl<'a, A> Arbitrary<'a> for $range
where
A: Arbitrary<'a> + Clone + PartialOrd,
{
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
let value: $value_ty = Arbitrary::arbitrary(u)?;
Ok($fun(value, $fun_closure))
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
$size_hint_closure(depth)
}
}
};
}
impl_range!(
Range<A>,
|r: &Range<A>| (r.start.clone(), r.end.clone()),
(A, A),
bounded_range(|(a, b)| a..b),
|depth| crate::size_hint::and(
<A as Arbitrary>::size_hint(depth),
<A as Arbitrary>::size_hint(depth)
)
);
impl_range!(
RangeFrom<A>,
|r: &RangeFrom<A>| r.start.clone(),
A,
unbounded_range(|a| a..),
|depth| <A as Arbitrary>::size_hint(depth)
);
impl_range!(
RangeInclusive<A>,
|r: &RangeInclusive<A>| (r.start().clone(), r.end().clone()),
(A, A),
bounded_range(|(a, b)| a..=b),
|depth| crate::size_hint::and(
<A as Arbitrary>::size_hint(depth),
<A as Arbitrary>::size_hint(depth)
)
);
impl_range!(
RangeTo<A>,
|r: &RangeTo<A>| r.end.clone(),
A,
unbounded_range(|b| ..b),
|depth| <A as Arbitrary>::size_hint(depth)
);
impl_range!(
RangeToInclusive<A>,
|r: &RangeToInclusive<A>| r.end.clone(),
A,
unbounded_range(|b| ..=b),
|depth| <A as Arbitrary>::size_hint(depth)
);
pub(crate) fn bounded_range<CB, I, R>(bounds: (I, I), cb: CB) -> R
where
CB: Fn((I, I)) -> R,
I: PartialOrd,
R: RangeBounds<I>,
{
let (mut start, mut end) = bounds;
if start > end {
mem::swap(&mut start, &mut end);
}
cb((start, end))
}
pub(crate) fn unbounded_range<CB, I, R>(bound: I, cb: CB) -> R
where
CB: Fn(I) -> R,
R: RangeBounds<I>,
{
cb(bound)
}
impl<'a> Arbitrary<'a> for Duration {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Ok(Self::new(
<u64 as Arbitrary>::arbitrary(u)?,
u.int_in_range(0..=999_999_999)?,
))
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
crate::size_hint::and(
<u64 as Arbitrary>::size_hint(depth),
<u32 as Arbitrary>::size_hint(depth),
)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for Option<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Ok(if <bool as Arbitrary<'a>>::arbitrary(u)? {
Some(Arbitrary::arbitrary(u)?)
} else {
None
})
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
crate::size_hint::and(
<bool as Arbitrary>::size_hint(depth),
crate::size_hint::or((0, Some(0)), <A as Arbitrary>::size_hint(depth)),
)
}
}
impl<'a, A: Arbitrary<'a>, B: Arbitrary<'a>> Arbitrary<'a> for std::result::Result<A, B> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Ok(if <bool as Arbitrary<'a>>::arbitrary(u)? {
Ok(<A as Arbitrary>::arbitrary(u)?)
} else {
Err(<B as Arbitrary>::arbitrary(u)?)
})
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
crate::size_hint::and(
<bool as Arbitrary>::size_hint(depth),
crate::size_hint::or(
<A as Arbitrary>::size_hint(depth),
<B as Arbitrary>::size_hint(depth),
),
)
}
}
macro_rules! arbitrary_tuple {
() => {};
($last: ident $($xs: ident)*) => {
arbitrary_tuple!($($xs)*);
impl<'a, $($xs: Arbitrary<'a>,)* $last: Arbitrary<'a>> Arbitrary<'a> for ($($xs,)* $last,) {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Ok(($($xs::arbitrary(u)?,)* Arbitrary::arbitrary(u)?,))
}
#[allow(unused_mut, non_snake_case)]
fn arbitrary_take_rest(mut u: Unstructured<'a>) -> Result<Self> {
$(let $xs = $xs::arbitrary(&mut u)?;)*
let $last = $last::arbitrary_take_rest(u)?;
Ok(($($xs,)* $last,))
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
crate::size_hint::and_all(&[
<$last as Arbitrary>::size_hint(depth),
$( <$xs as Arbitrary>::size_hint(depth) ),*
])
}
}
};
}
arbitrary_tuple!(A B C D E F G H I J K L M N O P Q R S T U V W X Y Z);
// Helper to safely create arrays since the standard library doesn't
// provide one yet. Shouldn't be necessary in the future.
struct ArrayGuard<T, const N: usize> {
dst: *mut T,
initialized: usize,
}
impl<T, const N: usize> Drop for ArrayGuard<T, N> {
fn drop(&mut self) {
debug_assert!(self.initialized <= N);
let initialized_part = core::ptr::slice_from_raw_parts_mut(self.dst, self.initialized);
unsafe {
core::ptr::drop_in_place(initialized_part);
}
}
}
fn try_create_array<F, T, const N: usize>(mut cb: F) -> Result<[T; N]>
where
F: FnMut(usize) -> Result<T>,
{
let mut array: mem::MaybeUninit<[T; N]> = mem::MaybeUninit::uninit();
let array_ptr = array.as_mut_ptr();
let dst = array_ptr as _;
let mut guard: ArrayGuard<T, N> = ArrayGuard {
dst,
initialized: 0,
};
unsafe {
for (idx, value_ptr) in (*array.as_mut_ptr()).iter_mut().enumerate() {
core::ptr::write(value_ptr, cb(idx)?);
guard.initialized += 1;
}
mem::forget(guard);
Ok(array.assume_init())
}
}
impl<'a, T, const N: usize> Arbitrary<'a> for [T; N]
where
T: Arbitrary<'a>,
{
#[inline]
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
try_create_array(|_| <T as Arbitrary<'a>>::arbitrary(u))
}
#[inline]
fn arbitrary_take_rest(mut u: Unstructured<'a>) -> Result<Self> {
let mut array = Self::arbitrary(&mut u)?;
if let Some(last) = array.last_mut() {
*last = Arbitrary::arbitrary_take_rest(u)?;
}
Ok(array)
}
#[inline]
fn size_hint(d: usize) -> (usize, Option<usize>) {
crate::size_hint::and_all(&array::from_fn::<_, N, _>(|_| {
<T as Arbitrary>::size_hint(d)
}))
}
}
impl<'a> Arbitrary<'a> for &'a [u8] {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
let len = u.arbitrary_len::<u8>()?;
u.bytes(len)
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
Ok(u.take_rest())
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, None)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for Vec<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
u.arbitrary_iter()?.collect()
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
u.arbitrary_take_rest_iter()?.collect()
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, None)
}
}
impl<'a, K: Arbitrary<'a> + Ord, V: Arbitrary<'a>> Arbitrary<'a> for BTreeMap<K, V> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
u.arbitrary_iter()?.collect()
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
u.arbitrary_take_rest_iter()?.collect()
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, None)
}
}
impl<'a, A: Arbitrary<'a> + Ord> Arbitrary<'a> for BTreeSet<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
u.arbitrary_iter()?.collect()
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
u.arbitrary_take_rest_iter()?.collect()
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, None)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for Bound<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
match u.int_in_range::<u8>(0..=2)? {
0 => Ok(Bound::Included(A::arbitrary(u)?)),
1 => Ok(Bound::Excluded(A::arbitrary(u)?)),
2 => Ok(Bound::Unbounded),
_ => unreachable!(),
}
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
size_hint::or(
size_hint::and((1, Some(1)), A::size_hint(depth)),
(1, Some(1)),
)
}
}
impl<'a, A: Arbitrary<'a> + Ord> Arbitrary<'a> for BinaryHeap<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
u.arbitrary_iter()?.collect()
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
u.arbitrary_take_rest_iter()?.collect()
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, None)
}
}
impl<'a, K: Arbitrary<'a> + Eq + ::std::hash::Hash, V: Arbitrary<'a>, S: BuildHasher + Default>
Arbitrary<'a> for HashMap<K, V, S>
{
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
u.arbitrary_iter()?.collect()
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
u.arbitrary_take_rest_iter()?.collect()
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, None)
}
}
impl<'a, A: Arbitrary<'a> + Eq + ::std::hash::Hash, S: BuildHasher + Default> Arbitrary<'a>
for HashSet<A, S>
{
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
u.arbitrary_iter()?.collect()
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
u.arbitrary_take_rest_iter()?.collect()
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, None)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for LinkedList<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
u.arbitrary_iter()?.collect()
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
u.arbitrary_take_rest_iter()?.collect()
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, None)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for VecDeque<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
u.arbitrary_iter()?.collect()
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
u.arbitrary_take_rest_iter()?.collect()
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, None)
}
}
impl<'a, A> Arbitrary<'a> for Cow<'a, A>
where
A: ToOwned + ?Sized,
<A as ToOwned>::Owned: Arbitrary<'a>,
{
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Cow::Owned)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
crate::size_hint::recursion_guard(depth, |depth| {
<<A as ToOwned>::Owned as Arbitrary>::size_hint(depth)
})
}
}
impl<'a> Arbitrary<'a> for &'a str {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
let size = u.arbitrary_len::<u8>()?;
match str::from_utf8(u.peek_bytes(size).unwrap()) {
Ok(s) => {
u.bytes(size).unwrap();
Ok(s)
}
Err(e) => {
let i = e.valid_up_to();
let valid = u.bytes(i).unwrap();
let s = unsafe {
debug_assert!(str::from_utf8(valid).is_ok());
str::from_utf8_unchecked(valid)
};
Ok(s)
}
}
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
let bytes = u.take_rest();
str::from_utf8(bytes).map_err(|_| Error::IncorrectFormat)
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, None)
}
}
impl<'a> Arbitrary<'a> for String {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
<&str as Arbitrary>::arbitrary(u).map(Into::into)
}
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self> {
<&str as Arbitrary>::arbitrary_take_rest(u).map(Into::into)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<&str as Arbitrary>::size_hint(depth)
}
}
impl<'a> Arbitrary<'a> for CString {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
<Vec<u8> as Arbitrary>::arbitrary(u).map(|mut x| {
x.retain(|&c| c != 0);
Self::new(x).unwrap()
})
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<Vec<u8> as Arbitrary>::size_hint(depth)
}
}
impl<'a> Arbitrary<'a> for OsString {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
<String as Arbitrary>::arbitrary(u).map(From::from)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<String as Arbitrary>::size_hint(depth)
}
}
impl<'a> Arbitrary<'a> for PathBuf {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
<OsString as Arbitrary>::arbitrary(u).map(From::from)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<OsString as Arbitrary>::size_hint(depth)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for Box<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Self::new)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
crate::size_hint::recursion_guard(depth, <A as Arbitrary>::size_hint)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for Box<[A]> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
<Vec<A> as Arbitrary>::arbitrary(u).map(|x| x.into_boxed_slice())
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<Vec<A> as Arbitrary>::size_hint(depth)
}
}
impl<'a> Arbitrary<'a> for Box<str> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
<String as Arbitrary>::arbitrary(u).map(|x| x.into_boxed_str())
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<String as Arbitrary>::size_hint(depth)
}
}
// impl Arbitrary for Box<CStr> {
// fn arbitrary(u: &mut Unstructured<'_>) -> Result<Self> {
// <CString as Arbitrary>::arbitrary(u).map(|x| x.into_boxed_c_str())
// }
// }
// impl Arbitrary for Box<OsStr> {
// fn arbitrary(u: &mut Unstructured<'_>) -> Result<Self> {
// <OsString as Arbitrary>::arbitrary(u).map(|x| x.into_boxed_osstr())
//
// }
// }
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for Arc<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Self::new)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
crate::size_hint::recursion_guard(depth, <A as Arbitrary>::size_hint)
}
}
impl<'a> Arbitrary<'a> for Arc<str> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
<&str as Arbitrary>::arbitrary(u).map(Into::into)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<&str as Arbitrary>::size_hint(depth)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for Rc<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Self::new)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
crate::size_hint::recursion_guard(depth, <A as Arbitrary>::size_hint)
}
}
impl<'a> Arbitrary<'a> for Rc<str> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
<&str as Arbitrary>::arbitrary(u).map(Into::into)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<&str as Arbitrary>::size_hint(depth)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for Cell<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Self::new)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<A as Arbitrary<'a>>::size_hint(depth)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for RefCell<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Self::new)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<A as Arbitrary<'a>>::size_hint(depth)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for UnsafeCell<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Self::new)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<A as Arbitrary<'a>>::size_hint(depth)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for Mutex<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(Self::new)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<A as Arbitrary<'a>>::size_hint(depth)
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for iter::Empty<A> {
fn arbitrary(_: &mut Unstructured<'a>) -> Result<Self> {
Ok(iter::empty())
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, Some(0))
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for ::std::marker::PhantomData<A> {
fn arbitrary(_: &mut Unstructured<'a>) -> Result<Self> {
Ok(::std::marker::PhantomData)
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(0, Some(0))
}
}
impl<'a, A: Arbitrary<'a>> Arbitrary<'a> for ::std::num::Wrapping<A> {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Arbitrary::arbitrary(u).map(::std::num::Wrapping)
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<A as Arbitrary<'a>>::size_hint(depth)
}
}
macro_rules! implement_nonzero_int {
($nonzero:ty, $int:ty) => {
impl<'a> Arbitrary<'a> for $nonzero {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
match Self::new(<$int as Arbitrary<'a>>::arbitrary(u)?) {
Some(n) => Ok(n),
None => Err(Error::IncorrectFormat),
}
}
#[inline]
fn size_hint(depth: usize) -> (usize, Option<usize>) {
<$int as Arbitrary<'a>>::size_hint(depth)
}
}
};
}
implement_nonzero_int! { NonZeroI8, i8 }
implement_nonzero_int! { NonZeroI16, i16 }
implement_nonzero_int! { NonZeroI32, i32 }
implement_nonzero_int! { NonZeroI64, i64 }
implement_nonzero_int! { NonZeroI128, i128 }
implement_nonzero_int! { NonZeroIsize, isize }
implement_nonzero_int! { NonZeroU8, u8 }
implement_nonzero_int! { NonZeroU16, u16 }
implement_nonzero_int! { NonZeroU32, u32 }
implement_nonzero_int! { NonZeroU64, u64 }
implement_nonzero_int! { NonZeroU128, u128 }
implement_nonzero_int! { NonZeroUsize, usize }
impl<'a> Arbitrary<'a> for Ipv4Addr {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Ok(Ipv4Addr::from(u32::arbitrary(u)?))
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(4, Some(4))
}
}
impl<'a> Arbitrary<'a> for Ipv6Addr {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Ok(Ipv6Addr::from(u128::arbitrary(u)?))
}
#[inline]
fn size_hint(_depth: usize) -> (usize, Option<usize>) {
(16, Some(16))
}
}
#[cfg(test)]
mod test {
use super::*;
/// Generates an arbitrary `T`, and checks that the result is consistent with the
/// `size_hint()` reported by `T`.
fn checked_arbitrary<'a, T: Arbitrary<'a>>(u: &mut Unstructured<'a>) -> Result<T> {
let (min, max) = T::size_hint(0);
let len_before = u.len();
let result = T::arbitrary(u);
let consumed = len_before - u.len();
if let Some(max) = max {
assert!(
consumed <= max,
"incorrect maximum size: indicated {}, actually consumed {}",
max,
consumed
);
}
if result.is_ok() {
assert!(
consumed >= min,
"incorrect minimum size: indicated {}, actually consumed {}",
min,
consumed
);
}
result
}
/// Like `checked_arbitrary()`, but calls `arbitrary_take_rest()` instead of `arbitrary()`.
fn checked_arbitrary_take_rest<'a, T: Arbitrary<'a>>(u: Unstructured<'a>) -> Result<T> {
let (min, _) = T::size_hint(0);
let len_before = u.len();
let result = T::arbitrary_take_rest(u);
if result.is_ok() {
assert!(
len_before >= min,
"incorrect minimum size: indicated {}, worked with {}",
min,
len_before
);
}
result
}
#[test]
fn finite_buffer_fill_buffer() {
let x = [1, 2, 3, 4];
let mut rb = Unstructured::new(&x);
let mut z = [0; 2];
rb.fill_buffer(&mut z).unwrap();
assert_eq!(z, [1, 2]);
rb.fill_buffer(&mut z).unwrap();
assert_eq!(z, [3, 4]);
rb.fill_buffer(&mut z).unwrap();
assert_eq!(z, [0, 0]);
}
#[test]
fn arbitrary_for_integers() {
let x = [1, 2, 3, 4];
let mut buf = Unstructured::new(&x);
let expected = 1 | (2 << 8) | (3 << 16) | (4 << 24);
let actual = checked_arbitrary::<i32>(&mut buf).unwrap();
assert_eq!(expected, actual);
}
#[test]
fn arbitrary_for_bytes() {
let x = [1, 2, 3, 4, 4];
let mut buf = Unstructured::new(&x);
let expected = &[1, 2, 3, 4];
let actual = checked_arbitrary::<&[u8]>(&mut buf).unwrap();
assert_eq!(expected, actual);
}
#[test]
fn arbitrary_take_rest_for_bytes() {
let x = [1, 2, 3, 4];
let buf = Unstructured::new(&x);
let expected = &[1, 2, 3, 4];
let actual = checked_arbitrary_take_rest::<&[u8]>(buf).unwrap();
assert_eq!(expected, actual);
}
#[test]
fn arbitrary_collection() {
let x = [
1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 12,
];
assert_eq!(
checked_arbitrary::<&[u8]>(&mut Unstructured::new(&x)).unwrap(),
&[1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 2, 3]
);
assert_eq!(
checked_arbitrary::<Vec<u8>>(&mut Unstructured::new(&x)).unwrap(),
&[2, 4, 6, 8, 1]
);
assert_eq!(
checked_arbitrary::<Vec<u32>>(&mut Unstructured::new(&x)).unwrap(),
&[84148994]
);
assert_eq!(
checked_arbitrary::<String>(&mut Unstructured::new(&x)).unwrap(),
"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x01\x02\x03"
);
}
#[test]
fn arbitrary_take_rest() {
let x = [1, 2, 3, 4];
assert_eq!(
checked_arbitrary_take_rest::<&[u8]>(Unstructured::new(&x)).unwrap(),
&[1, 2, 3, 4]
);
assert_eq!(
checked_arbitrary_take_rest::<Vec<u8>>(Unstructured::new(&x)).unwrap(),
&[1, 2, 3, 4]
);
assert_eq!(
checked_arbitrary_take_rest::<Vec<u32>>(Unstructured::new(&x)).unwrap(),
&[0x4030201]
);
assert_eq!(
checked_arbitrary_take_rest::<String>(Unstructured::new(&x)).unwrap(),
"\x01\x02\x03\x04"
);
assert_eq!(
checked_arbitrary_take_rest::<&[u8]>(Unstructured::new(&[])).unwrap(),
&[]
);
assert_eq!(
checked_arbitrary_take_rest::<Vec<u8>>(Unstructured::new(&[])).unwrap(),
&[]
);
}
#[test]
fn size_hint_for_tuples() {
assert_eq!(
(7, Some(7)),
<(bool, u16, i32) as Arbitrary<'_>>::size_hint(0)
);
assert_eq!((1, None), <(u8, Vec<u8>) as Arbitrary>::size_hint(0));
}
}
/// Multiple conflicting arbitrary attributes are used on the same field:
/// ```compile_fail
/// #[derive(::arbitrary::Arbitrary)]
/// struct Point {
/// #[arbitrary(value = 2)]
/// #[arbitrary(value = 2)]
/// x: i32,
/// }
/// ```
///
/// An unknown attribute:
/// ```compile_fail
/// #[derive(::arbitrary::Arbitrary)]
/// struct Point {
/// #[arbitrary(unknown_attr)]
/// x: i32,
/// }
/// ```
///
/// An unknown attribute with a value:
/// ```compile_fail
/// #[derive(::arbitrary::Arbitrary)]
/// struct Point {
/// #[arbitrary(unknown_attr = 13)]
/// x: i32,
/// }
/// ```
///
/// `value` without RHS:
/// ```compile_fail
/// #[derive(::arbitrary::Arbitrary)]
/// struct Point {
/// #[arbitrary(value)]
/// x: i32,
/// }
/// ```
///
/// `with` without RHS:
/// ```compile_fail
/// #[derive(::arbitrary::Arbitrary)]
/// struct Point {
/// #[arbitrary(with)]
/// x: i32,
/// }
/// ```
///
/// Multiple conflicting bounds at the container-level:
/// ```compile_fail
/// #[derive(::arbitrary::Arbitrary)]
/// #[arbitrary(bound = "T: Default")]
/// #[arbitrary(bound = "T: Default")]
/// struct Point<T: Default> {
/// #[arbitrary(default)]
/// x: T,
/// }
/// ```
///
/// Multiple conflicting bounds in a single bound attribute:
/// ```compile_fail
/// #[derive(::arbitrary::Arbitrary)]
/// #[arbitrary(bound = "T: Default, T: Default")]
/// struct Point<T: Default> {
/// #[arbitrary(default)]
/// x: T,
/// }
/// ```
///
/// Multiple conflicting bounds in multiple bound attributes:
/// ```compile_fail
/// #[derive(::arbitrary::Arbitrary)]
/// #[arbitrary(bound = "T: Default", bound = "T: Default")]
/// struct Point<T: Default> {
/// #[arbitrary(default)]
/// x: T,
/// }
/// ```
///
/// Too many bounds supplied:
/// ```compile_fail
/// #[derive(::arbitrary::Arbitrary)]
/// #[arbitrary(bound = "T: Default")]
/// struct Point {
/// x: i32,
/// }
/// ```
///
/// Too many bounds supplied across multiple attributes:
/// ```compile_fail
/// #[derive(::arbitrary::Arbitrary)]
/// #[arbitrary(bound = "T: Default")]
/// #[arbitrary(bound = "U: Default")]
/// struct Point<T: Default> {
/// #[arbitrary(default)]
/// x: T,
/// }
/// ```
#[cfg(all(doctest, feature = "derive"))]
pub struct CompileFailTests;