Test for issue-86035

src/test/ui/imports/auxiliary/overlapping_pub_trait_source.rs

@@ -0,0 +1,13 @@
+/* This crate declares an item as both `prelude::*` and `m::Tr`.
+ * The compiler should always suggest `m::Tr`. */
+
+pub struct S;
+
+pub mod prelude {
+    pub use crate::m::Tr as _;
+}
+
+pub mod m {
+    pub trait Tr { fn method(&self); }
+    impl Tr for crate::S { fn method(&self) {} }
+}

src/test/ui/imports/auxiliary/unnamed_pub_trait_source.rs

@@ -0,0 +1,13 @@
+/* This crate declares an item that is unnamed.
+ * Its only public path is through `prelude::*`. */
+
+pub struct S;
+
+mod m {
+    pub trait Tr { fn method(&self); }
+    impl Tr for crate::S { fn method(&self) {} }
+}
+
+pub mod prelude {
+    pub use crate::m::Tr as _;
+}

src/test/ui/imports/overlapping_pub_trait.rs

@@ -0,0 +1,15 @@
+// aux-build:overlapping_pub_trait_source.rs
+
+/*
+ * This crate declares two public paths, `m::Tr` and `prelude::_`. Make sure we prefer the former.
+ */
+extern crate overlapping_pub_trait_source;
+
+fn main() {
+    //~^ HELP the following trait is implemented but not in scope; perhaps add a `use` for it:
+    //~| SUGGESTION overlapping_pub_trait_source::prelude::_
+    use overlapping_pub_trait_source::S;
+    S.method();
+    //~^ ERROR no method named `method` found for struct `S` in the current scope [E0599]
+    //~| HELP items from traits can only be used if the trait is in scope
+}

src/test/ui/imports/overlapping_pub_trait.stderr

@@ -0,0 +1,20 @@
+error[E0599]: no method named `method` found for struct `S` in the current scope
+  --> $DIR/overlapping_pub_trait.rs:12:7
+   |
+LL |     S.method();
+   |       ^^^^^^ method not found in `S`
+   |
+  ::: $DIR/auxiliary/overlapping_pub_trait_source.rs:11:23
+   |
+LL |     pub trait Tr { fn method(&self); }
+   |                       ------ the method is available for `S` here
+   |
+   = help: items from traits can only be used if the trait is in scope
+help: the following trait is implemented but not in scope; perhaps add a `use` for it:
+   |
+LL | use overlapping_pub_trait_source::prelude::_;
+   |
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.

src/test/ui/imports/unnamed_pub_trait.rs

@@ -0,0 +1,16 @@
+// aux-build:unnamed_pub_trait_source.rs
+
+/*
+ * This crate declares an unnameable public path for our item. Make sure we don't suggest
+ * importing it by name, and instead we suggest importing it by glob.
+ */
+extern crate unnamed_pub_trait_source;
+
+fn main() {
+    //~^ HELP the following trait is implemented but not in scope; perhaps add a `use` for it:
+    //~| SUGGESTION unnamed_pub_trait_source::prelude::_
+    use unnamed_pub_trait_source::S;
+    S.method();
+    //~^ ERROR no method named `method` found for struct `S` in the current scope [E0599]
+    //~| HELP items from traits can only be used if the trait is in scope
+}

src/test/ui/imports/unnamed_pub_trait.stderr

@@ -0,0 +1,20 @@
+error[E0599]: no method named `method` found for struct `S` in the current scope
+  --> $DIR/unnamed_pub_trait.rs:13:7
+   |
+LL |     S.method();
+   |       ^^^^^^ method not found in `S`
+   |
+  ::: $DIR/auxiliary/unnamed_pub_trait_source.rs:7:23
+   |
+LL |     pub trait Tr { fn method(&self); }
+   |                       ------ the method is available for `S` here
+   |
+   = help: items from traits can only be used if the trait is in scope
+help: the following trait is implemented but not in scope; perhaps add a `use` for it:
+   |
+LL | use unnamed_pub_trait_source::prelude::_;
+   |
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.