1 files changed, 71 insertions, 0 deletions
diff --git a/src/test/ui/inherent-impls-overlap-check/overlap.rs b/src/test/ui/inherent-impls-overlap-check/overlap.rs
new file mode 100644
index 000000000..6f2801197
--- /dev/null
+++ b/src/test/ui/inherent-impls-overlap-check/overlap.rs
@@ -0,0 +1,71 @@
+// aux-build:repeat.rs
+
+#![allow(unused)]
+
+// This tests the allocating algo branch of the
+// inherent impls overlap checker.
+// This branch was added by PR:
+// https://github.com/rust-lang/rust/pull/78317
+// In this test, we repeat many impl blocks
+// to trigger the allocating branch.
+
+// Simple overlap
+
+extern crate repeat;
+
+struct Foo {}
+
+repeat::repeat_with_idents!(impl Foo { fn IDENT() {} });
+
+impl Foo { fn hello() {} } //~ERROR duplicate definitions with name `hello`
+impl Foo { fn hello() {} }
+
+// Transitive overlap
+
+struct Foo2 {}
+
+repeat::repeat_with_idents!(impl Foo2 { fn IDENT() {} });
+
+impl Foo2 {
+    fn bar() {}
+    fn hello2() {} //~ERROR duplicate definitions with name `hello2`
+}
+
+impl Foo2 {
+    fn baz() {}
+    fn hello2() {}
+}
+
+// Slightly stronger transitive overlap
+
+struct Foo3 {}
+
+repeat::repeat_with_idents!(impl Foo3 { fn IDENT() {} });
+
+impl Foo3 {
+    fn bar() {} //~ERROR duplicate definitions with name `bar`
+    fn hello3() {} //~ERROR duplicate definitions with name `hello3`
+}
+
+impl Foo3 {
+    fn bar() {}
+    fn hello3() {}
+}
+
+// Generic overlap
+
+struct Bar<T>(T);
+
+struct A;
+struct B;
+
+repeat::repeat_with_idents!(impl Bar<A> { fn IDENT() {} });
+
+impl Bar<A> { fn foo() {} fn bar2() {} }
+impl Bar<B> {
+    fn foo() {}
+    fn bar2() {} //~ERROR duplicate definitions with name `bar2`
+}
+impl Bar<B> { fn bar2() {} }
+
+fn main() {}