31 lines
921 B
Rust
31 lines
921 B
Rust
#![feature(auto_traits)]
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#![feature(negative_impls)]
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// Test for issue #56934 - that it is impossible to redundantly
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// implement an auto-trait for a trait object type that contains it.
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// Negative impl variant.
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auto trait Marker1 {}
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auto trait Marker2 {}
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trait Object: Marker1 {}
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// A supertrait marker is illegal...
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impl !Marker1 for dyn Object + Marker2 { } //~ ERROR E0371
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// ...and also a direct component.
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impl !Marker2 for dyn Object + Marker2 { } //~ ERROR E0371
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// But implementing a marker if it is not present is OK.
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impl !Marker2 for dyn Object {} // OK
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// A non-principal trait-object type is orphan even in its crate.
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impl !Send for dyn Marker2 {} //~ ERROR E0117
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// And impl'ing a remote marker for a local trait object is forbidden
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// by one of these special orphan-like rules.
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impl !Send for dyn Object {} //~ ERROR E0321
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impl !Send for dyn Object + Marker2 {} //~ ERROR E0321
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fn main() { }
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