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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /src/test/ui/traits/alias/no-duplicates.rs
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/test/ui/traits/alias/no-duplicates.rs')
-rw-r--r--src/test/ui/traits/alias/no-duplicates.rs126
1 files changed, 126 insertions, 0 deletions
diff --git a/src/test/ui/traits/alias/no-duplicates.rs b/src/test/ui/traits/alias/no-duplicates.rs
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+// The purpose of this test is to demonstrate that duplicating object safe traits
+// that are not auto traits is rejected with trait aliases even though one could
+// reasonably accept this.
+
+#![feature(trait_alias)]
+
+use std::marker::Unpin;
+
+// Some arbitrary object-safe trait:
+trait Obj {}
+
+// Nest a few levels deep:
+trait _0 = Obj;
+trait _1 = _0;
+
+type _T00 = dyn _0 + _0;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T01 = dyn _1 + _0;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T02 = dyn _1 + _1;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T03 = dyn Obj + _1;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T04 = dyn _1 + Obj;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+// Nest some more and in weird ways:
+
+trait _2 = _0 + _1;
+trait _3 = Obj;
+trait _4 = _3;
+
+type _T10 = dyn _2 + _3;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T11 = dyn _3 + _2;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T12 = dyn Obj + _2;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T13 = dyn _2 + Obj;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T14 = dyn _1 + _3;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T15 = dyn _3 + _1;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T16 = dyn _1 + _4;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T17 = dyn _4 + _1;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+// Include auto traits:
+
+trait _5 = Obj + Send;
+
+type _T20 = dyn _5 + _5;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T21 = dyn Obj + _5;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T22 = dyn _5 + Obj;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T23 = dyn _5 + Send + Sync + Obj;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+// Also nest:
+
+trait _6 = _5 + _5; // ==> Obj + Send + Obj + Send
+
+type _T30 = dyn _6;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T31 = dyn _6 + Send;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T32 = dyn Send + _6;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+// Nest some more:
+
+trait _7 = _5 + Sync;
+trait _8 = Unpin + _7;
+
+type _T40 = dyn _8 + Obj;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T41 = dyn Obj + _8;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T42 = dyn _8 + _4;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T43 = dyn _4 + _8;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+type _T44 = dyn _4 + Send + Sync + _8;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+// Take higher ranked types into account.
+
+// Note that `'a` and `'b` are intentionally different to make sure we consider
+// them semantically the same.
+trait ObjL<'l> {}
+trait _9 = for<'a> ObjL<'a>;
+trait _10 = for<'b> ObjL<'b>;
+type _T50 = dyn _9 + _10;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+trait ObjT<T> {}
+trait _11 = ObjT<for<'a> fn(&'a u8)>;
+trait _12 = ObjT<for<'b> fn(&'b u8)>;
+type _T60 = dyn _11 + _12;
+//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
+
+fn main() {}