48 lines
933 B
Rust
48 lines
933 B
Rust
// run-pass
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use std::mem::size_of;
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// The main point of this test is to ensure that we can parse and resolve
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// associated items on associated types.
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trait Foo {
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type U;
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}
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trait Bar {
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// Note 1: Chains of associated items in a path won't type-check.
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// Note 2: Associated consts can't depend on type parameters or `Self`,
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// which are the only types that an associated type can be referenced on for
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// now, so we can only test methods.
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fn method() -> u32;
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fn generic_method<T>() -> usize;
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}
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struct MyFoo;
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struct MyBar;
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impl Foo for MyFoo {
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type U = MyBar;
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}
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impl Bar for MyBar {
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fn method() -> u32 {
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2u32
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}
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fn generic_method<T>() -> usize {
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size_of::<T>()
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}
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}
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fn foo<T>()
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where T: Foo,
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T::U: Bar,
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{
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assert_eq!(2u32, <T as Foo>::U::method());
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assert_eq!(8usize, <T as Foo>::U::generic_method::<f64>());
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}
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fn main() {
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foo::<MyFoo>();
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}
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