Merge remote-tracking branch 'origin/main' into afromher_debug

1 files changed, 341 insertions, 0 deletions

diff --git a/tests/src/traits.rs b/tests/src/traits.rs
new file mode 100644
index 00000000..27c90586
--- /dev/null
+++ b/tests/src/traits.rs
@@ -0,0 +1,341 @@
+pub trait BoolTrait {
+    // Required method
+    fn get_bool(&self) -> bool;
+
+    // Provided method
+    fn ret_true(&self) -> bool {
+        true
+    }
+}
+
+impl BoolTrait for bool {
+    fn get_bool(&self) -> bool {
+        *self
+    }
+}
+
+pub fn test_bool_trait_bool(x: bool) -> bool {
+    x.get_bool() && x.ret_true()
+}
+
+#[allow(clippy::redundant_pattern_matching)]
+impl<T> BoolTrait for Option<T> {
+    fn get_bool(&self) -> bool {
+        match self {
+            Option::Some(_) => true,
+            Option::None => false,
+        }
+    }
+}
+
+pub fn test_bool_trait_option<T>(x: Option<T>) -> bool {
+    x.get_bool() && x.ret_true()
+}
+
+pub fn test_bool_trait<T: BoolTrait>(x: T) -> bool {
+    x.get_bool()
+}
+
+pub trait ToU64 {
+    fn to_u64(self) -> u64;
+}
+
+impl ToU64 for u64 {
+    fn to_u64(self) -> u64 {
+        self
+    }
+}
+
+impl<A: ToU64> ToU64 for (A, A) {
+    fn to_u64(self) -> u64 {
+        self.0.to_u64() + self.1.to_u64()
+    }
+}
+
+pub fn f<T: ToU64>(x: (T, T)) -> u64 {
+    x.to_u64()
+}
+
+pub fn g<T>(x: (T, T)) -> u64
+where
+    (T, T): ToU64,
+{
+    x.to_u64()
+}
+
+pub fn h0(x: u64) -> u64 {
+    x.to_u64()
+}
+
+pub struct Wrapper<T> {
+    x: T,
+}
+
+impl<T: ToU64> ToU64 for Wrapper<T> {
+    fn to_u64(self) -> u64 {
+        self.x.to_u64()
+    }
+}
+
+pub fn h1(x: Wrapper<u64>) -> u64 {
+    x.to_u64()
+}
+
+pub fn h2<T: ToU64>(x: Wrapper<T>) -> u64 {
+    x.to_u64()
+}
+
+pub trait ToType<T> {
+    fn to_type(self) -> T;
+}
+
+impl ToType<bool> for u64 {
+    fn to_type(self) -> bool {
+        self > 0
+    }
+}
+
+pub trait OfType {
+    fn of_type<T: ToType<Self>>(x: T) -> Self
+    where
+        Self: std::marker::Sized;
+}
+
+pub fn h3<T1: OfType, T2: ToType<T1>>(y: T2) -> T1 {
+    T1::of_type(y)
+}
+
+// Checking what happens if we move trait clauses from a method to its enclosing block
+pub trait OfTypeBis<T: ToType<Self>>
+where
+    Self: std::marker::Sized,
+{
+    fn of_type(x: T) -> Self
+    where
+        Self: std::marker::Sized;
+}
+
+pub fn h4<T1: OfTypeBis<T2>, T2: ToType<T1>>(y: T2) -> T1 {
+    T1::of_type(y)
+}
+
+pub struct TestType<T>(T);
+
+// Checking what happens with nested blocks
+impl<T: ToU64> TestType<T> {
+    pub fn test(&self, x: T) -> bool {
+        struct TestType1(u64);
+        trait TestTrait {
+            fn test(&self) -> bool;
+        }
+
+        // Remark: we can't write: impl TestTrait for TestType<T>,
+        // we have to use a *local* parameter (can't use the outer T).
+        // In other words: the parameters used in the items inside
+        // an impl must be bound by the impl block (can't come from outer
+        // blocks).
+
+        impl TestTrait for TestType1 {
+            fn test(&self) -> bool {
+                self.0 > 1
+            }
+        }
+
+        let x = x.to_u64();
+        let y = TestType1(0);
+        x > 0 && y.test()
+    }
+}
+
+pub struct BoolWrapper(pub bool);
+
+impl<T> ToType<T> for BoolWrapper
+where
+    bool: ToType<T>,
+{
+    fn to_type(self) -> T {
+        self.0.to_type()
+    }
+}
+
+pub trait WithConstTy<const LEN: usize> {
+    const LEN1: usize;
+    // Testing default values
+    const LEN2: usize = 32;
+
+    type V;
+    type W: ToU64;
+
+    // Below: we can't use [Self::Len1] in the type of the array.
+    // Probably because of dyn traits...
+    fn f(x: &mut Self::W, y: &[u8; LEN]);
+}
+
+impl WithConstTy<32> for bool {
+    const LEN1: usize = 12;
+
+    type V = u8;
+    type W = u64;
+
+    fn f(_: &mut Self::W, _: &[u8; 32]) {}
+}
+
+pub fn use_with_const_ty1<const LEN: usize, H: WithConstTy<LEN>>() -> usize {
+    H::LEN1
+}
+
+pub fn use_with_const_ty2<const LEN: usize, H: WithConstTy<LEN>>(_: H::W) {}
+
+pub fn use_with_const_ty3<const LEN: usize, H: WithConstTy<LEN>>(x: H::W) -> u64 {
+    x.to_u64()
+}
+
+pub fn test_where1<'a, T: 'a>(_x: &'a T) {}
+pub fn test_where2<T: WithConstTy<32, V = u32>>(_x: T::V) {}
+
+// Below: testing super traits.
+//
+// Actually, this comes for free: ChildTrait : ParentTrait just adds a trait
+// clause for Self: `Self : ParentTrait`.
+pub trait ParentTrait0 {
+    type W;
+    fn get_name(&self) -> String;
+    fn get_w(&self) -> Self::W;
+}
+pub trait ParentTrait1 {}
+pub trait ChildTrait: ParentTrait0 + ParentTrait1 {}
+
+// But we still need to correctly reference the traits
+pub fn test_child_trait1<T: ChildTrait>(x: &T) -> String {
+    x.get_name()
+}
+
+pub fn test_child_trait2<T: ChildTrait>(x: &T) -> T::W {
+    x.get_w()
+}
+
+// Checking if the order has an importance (we use U::W before we declare that
+// U:ParentTrait0)
+pub fn order1<T: ParentTrait0<W = U::W>, U: ParentTrait0>() {}
+
+/* */
+pub trait ChildTrait1: ParentTrait1 {}
+
+impl ParentTrait1 for usize {}
+impl ChildTrait1 for usize {}
+
+/* [IntoIterator] is interesting because of the condition [Item = Self::Item]
+for the [IntoIter] associated type. */
+pub trait Iterator {
+    type Item;
+}
+
+pub trait IntoIterator {
+    type Item;
+    type IntoIter: Iterator<Item = Self::Item>;
+
+    // Required method
+    fn into_iter(self) -> Self::IntoIter;
+}
+
+/* The traits below are inspired by [Try] and [FromResidual].
+
+   The reference to `Self as Try` in the `FromResidual` clause used to
+   cause a bug.
+*/
+trait Try: FromResidual<<Self as Try>::Residual> {
+    type Residual;
+}
+
+trait FromResidual<T> {}
+
+pub trait WithTarget {
+    type Target;
+}
+
+pub trait ParentTrait2 {
+    type U: WithTarget;
+}
+
+pub trait ChildTrait2: ParentTrait2 {
+    fn convert(x: Self::U) -> <Self::U as WithTarget>::Target;
+}
+
+impl WithTarget for u32 {
+    type Target = u32;
+}
+
+impl ParentTrait2 for u32 {
+    type U = u32;
+}
+
+impl ChildTrait2 for u32 {
+    fn convert(x: u32) -> u32 {
+        x
+    }
+}
+
+/*
+// This one requires a lot of traits
+pub fn test_enumerate(x: usize) {
+    for _ in 0..x {}
+}
+*/
+
+/* Custom function pointers */
+pub trait CFnOnce<Args> {
+    type Output;
+
+    fn call_once(self, args: Args) -> Self::Output;
+}
+
+pub trait CFnMut<Args>: CFnOnce<Args> {
+    fn call_mut(&mut self, args: Args) -> Self::Output;
+}
+
+pub trait CFn<Args>: CFnMut<Args> {
+    fn call(&self, args: Args) -> Self::Output;
+}
+
+pub trait GetTrait {
+    type W;
+    fn get_w(&self) -> Self::W;
+}
+
+pub fn test_get_trait<T: GetTrait>(x: &T) -> T::W {
+    x.get_w()
+}
+
+// Constants with generics
+pub trait Trait {
+    const LEN: usize;
+}
+
+impl<const N: usize, T> Trait for [T; N] {
+    const LEN: usize = N;
+}
+
+impl<T: Trait> Trait for Wrapper<T> {
+    const LEN: usize = 0;
+}
+
+pub fn use_wrapper_len<T: Trait>() -> usize {
+    Wrapper::<T>::LEN
+}
+
+pub struct Foo<T, U> {
+    pub x: T,
+    pub y: U,
+}
+
+impl<T: Trait, U> Foo<T, U> {
+    pub const FOO: Result<T, i32> = Err(0);
+}
+
+pub fn use_foo1<T: Trait, U>() -> Result<T, i32> {
+    Foo::<T, U>::FOO
+}
+
+pub fn use_foo2<T, U: Trait>() -> Result<U, i32> {
+    Foo::<U, T>::FOO
+}