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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:19:13 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:19:13 +0000
commit218caa410aa38c29984be31a5229b9fa717560ee (patch)
treec54bd55eeb6e4c508940a30e94c0032fbd45d677 /tests/ui/coherence/coherence-impl-trait-for-marker-trait-negative.rs
parentReleasing progress-linux version 1.67.1+dfsg1-1~progress7.99u1. (diff)
downloadrustc-218caa410aa38c29984be31a5229b9fa717560ee.tar.xz
rustc-218caa410aa38c29984be31a5229b9fa717560ee.zip
Merging upstream version 1.68.2+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tests/ui/coherence/coherence-impl-trait-for-marker-trait-negative.rs')
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diff --git a/tests/ui/coherence/coherence-impl-trait-for-marker-trait-negative.rs b/tests/ui/coherence/coherence-impl-trait-for-marker-trait-negative.rs
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+++ b/tests/ui/coherence/coherence-impl-trait-for-marker-trait-negative.rs
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+#![feature(auto_traits)]
+#![feature(negative_impls)]
+
+// Test for issue #56934 - that it is impossible to redundantly
+// implement an auto-trait for a trait object type that contains it.
+
+// Negative impl variant.
+
+auto trait Marker1 {}
+auto trait Marker2 {}
+
+trait Object: Marker1 {}
+
+// A supertrait marker is illegal...
+impl !Marker1 for dyn Object + Marker2 { } //~ ERROR E0371
+// ...and also a direct component.
+impl !Marker2 for dyn Object + Marker2 { } //~ ERROR E0371
+
+// But implementing a marker if it is not present is OK.
+impl !Marker2 for dyn Object {} // OK
+
+// A non-principal trait-object type is orphan even in its crate.
+impl !Send for dyn Marker2 {} //~ ERROR E0117
+
+// And impl'ing a remote marker for a local trait object is forbidden
+// by one of these special orphan-like rules.
+impl !Send for dyn Object {} //~ ERROR E0321
+impl !Send for dyn Object + Marker2 {} //~ ERROR E0321
+
+fn main() { }