diff options
Diffstat (limited to 'src/test/ui/impl-trait/nested_impl_trait.rs')
-rw-r--r-- | src/test/ui/impl-trait/nested_impl_trait.rs | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/src/test/ui/impl-trait/nested_impl_trait.rs b/src/test/ui/impl-trait/nested_impl_trait.rs new file mode 100644 index 000000000..85c6f8c46 --- /dev/null +++ b/src/test/ui/impl-trait/nested_impl_trait.rs @@ -0,0 +1,32 @@ +use std::fmt::Debug; + +fn fine(x: impl Into<u32>) -> impl Into<u32> { x } + +fn bad_in_ret_position(x: impl Into<u32>) -> impl Into<impl Debug> { x } +//~^ ERROR nested `impl Trait` is not allowed +//~| ERROR the trait bound `impl Debug: From<impl Into<u32>>` is not satisfied + +fn bad_in_fn_syntax(x: fn() -> impl Into<impl Debug>) {} +//~^ ERROR nested `impl Trait` is not allowed +//~| `impl Trait` only allowed in function and inherent method return types + +fn bad_in_arg_position(_: impl Into<impl Debug>) { } +//~^ ERROR nested `impl Trait` is not allowed + +struct X; +impl X { + fn bad(x: impl Into<u32>) -> impl Into<impl Debug> { x } + //~^ ERROR nested `impl Trait` is not allowed + //~| ERROR the trait bound `impl Debug: From<impl Into<u32>>` is not satisfied +} + +fn allowed_in_assoc_type() -> impl Iterator<Item=impl Fn()> { + vec![|| println!("woot")].into_iter() +} + +fn allowed_in_ret_type() -> impl Fn() -> impl Into<u32> { +//~^ `impl Trait` only allowed in function and inherent method return types + || 5 +} + +fn main() {} |