#[macro_export]
macro_rules! clone_trait_object {
($($path:tt)+) => {
$crate::__internal_clone_trait_object!(begin $($path)+);
};
}
#[doc(hidden)]
#[macro_export]
macro_rules! __internal_clone_trait_object {
(begin < $($rest:tt)*) => {
$crate::__internal_clone_trait_object!(generics () () $($rest)*);
};
(begin $first:tt $($rest:tt)*) => {
$crate::__internal_clone_trait_object!(path () ($first) $($rest)*);
};
(generics ($($generics:tt)*) () > $($rest:tt)*) => {
$crate::__internal_clone_trait_object!(path ($($generics)*) () $($rest)*);
};
(generics ($($generics:tt)*) ($($brackets:tt)*) < $($rest:tt)*) => {
$crate::__internal_clone_trait_object!(generics ($($generics)* <) ($($brackets)* <) $($rest)*);
};
(generics ($($generics:tt)*) (< $($brackets:tt)*) > $($rest:tt)*) => {
$crate::__internal_clone_trait_object!(generics ($($generics)* >) ($($brackets)*) $($rest)*);
};
(generics ($($generics:tt)*) ($($brackets:tt)*) $first:tt $($rest:tt)*) => {
$crate::__internal_clone_trait_object!(generics ($($generics)* $first) ($($brackets)*) $($rest)*);
};
(path ($($generics:tt)*) ($($path:tt)*) where $($rest:tt)*) => {
$crate::__internal_clone_trait_object!(impl ($($generics)*) ($($path)*) ($($rest)*));
};
(path ($($generics:tt)*) ($($path:tt)*)) => {
$crate::__internal_clone_trait_object!(impl ($($generics)*) ($($path)*) ());
};
(path ($($generics:tt)*) ($($path:tt)*) $first:tt $($rest:tt)*) => {
$crate::__internal_clone_trait_object!(path ($($generics)*) ($($path)* $first) $($rest)*);
};
(impl ($($generics:tt)*) ($($path:tt)*) ($($bound:tt)*)) => {
impl<'clone, $($generics)*> $crate::private::clone::Clone for $crate::private::boxed::Box<dyn $($path)* + 'clone> where $($bound)* {
fn clone(&self) -> Self {
$crate::clone_box(&**self)
}
}
};
}
#[cfg(test)]
mod tests {
use crate::DynClone;
fn assert_clone<T: Clone>() {}
#[test]
fn test_plain() {
trait Trait: DynClone {}
clone_trait_object!(Trait);
assert_clone::<Box<dyn Trait>>();
}
#[test]
fn test_type_parameter() {
trait Trait<T>: DynClone {}
clone_trait_object!(<T> Trait<T>);
assert_clone::<Box<dyn Trait<u32>>>();
}
#[test]
fn test_generic_bound() {
trait Trait<T: PartialEq<T>, U>: DynClone {}
clone_trait_object!(<T: PartialEq<T>, U> Trait<T, U>);
assert_clone::<Box<dyn Trait<u32, ()>>>();
}
#[test]
fn test_where_clause() {
trait Trait<T>: DynClone where T: Clone {}
clone_trait_object!(<T> Trait<T> where T: Clone);
assert_clone::<Box<dyn Trait<u32>>>();
}
}