fix tests

compiler/rustc_resolve/src/diagnostics.rs

@@ -1391,19 +1391,15 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                         crate_path.push(ast::PathSegment::path_root(rustc_span::DUMMY_SP));
                     }
                     crate_path.push(ast::PathSegment::from_ident(ident));
-                    let suggest_imports = self.lookup_import_candidates_from_module(
+
+                    suggestions.extend(self.lookup_import_candidates_from_module(
                         lookup_ident,
                         namespace,
                         parent_scope,
                         crate_root,
                         crate_path,
                         &filter_fn,
-                    );
-                    for item in suggest_imports {
-                        if suggestions.iter().all(|sugg| sugg.did != item.did) {
-                            suggestions.push(item);
-                        }
-                    }
+                    ));
                 }
             }
         }

tests/ui/hygiene/extern-prelude-from-opaque-fail-2018.stderr

@@ -24,8 +24,9 @@ LL |         fn f() { my_core::mem::drop(0); }
 LL | a!();
    | ---- in this macro invocation
    |
-   = help: consider importing this module:
+   = help: consider importing one of these items:
            core::mem
+           std::mem
    = note: this error originates in the macro `a` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0433]: failed to resolve: use of undeclared crate or module `my_core`
@@ -34,10 +35,12 @@ error[E0433]: failed to resolve: use of undeclared crate or module `my_core`
 LL |     fn f() { my_core::mem::drop(0); }
    |              ^^^^^^^ use of undeclared crate or module `my_core`
    |
-help: consider importing this module
+help: consider importing one of these items
    |
 LL +     use core::mem;
    |
+LL +     use std::mem;
+   |
 help: if you import `mem`, refer to it directly
    |
 LL -     fn f() { my_core::mem::drop(0); }

tests/ui/imports/issue-121168-2.rs

@@ -0,0 +1,12 @@
+//@ edition: 2018
+//@ compile-flags: --extern issue_121168_extern
+//@ aux-build: issue-121168-extern.rs
+
+extern crate issue_121168_extern as nice_crate_name;
+
+fn use_foo_from_another_crate_without_importing_it_first() {
+    //use nice_crate_name::Foo;
+    let _: Foo<i32> = todo!(); //~ ERROR cannot find type `Foo` in this scope
+}
+
+fn main() {}

tests/ui/imports/issue-121168-2.stderr

@@ -0,0 +1,16 @@
+error[E0412]: cannot find type `Foo` in this scope
+  --> $DIR/issue-121168-2.rs:9:12
+   |
+LL |     let _: Foo<i32> = todo!();
+   |            ^^^ not found in this scope
+   |
+help: consider importing one of these items
+   |
+LL + use crate::nice_crate_name::Foo;
+   |
+LL + use issue_121168_extern::Foo;
+   |
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0412`.

tests/ui/imports/issue-121168-3.rs

@@ -0,0 +1,12 @@
+//@ edition: 2015
+//@ compile-flags: --extern issue_121168_extern
+//@ aux-build: issue-121168-extern.rs
+
+extern crate issue_121168_extern as nice_crate_name;
+
+fn use_foo_from_another_crate_without_importing_it_first() {
+    //use nice_crate_name::Foo;
+    let _: Foo<i32> = todo!(); //~ ERROR cannot find type `Foo` in this scope
+}
+
+fn main() {}

tests/ui/imports/issue-121168-3.stderr

@@ -0,0 +1,14 @@
+error[E0412]: cannot find type `Foo` in this scope
+  --> $DIR/issue-121168-3.rs:9:12
+   |
+LL |     let _: Foo<i32> = todo!();
+   |            ^^^ not found in this scope
+   |
+help: consider importing this struct
+   |
+LL + use nice_crate_name::Foo;
+   |
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0412`.

tests/ui/imports/issue-121168.rs

@@ -0,0 +1,12 @@
+//@ edition: 2021
+//@ compile-flags: --extern issue_121168_extern
+//@ aux-build: issue-121168-extern.rs
+
+extern crate issue_121168_extern as nice_crate_name;
+
+fn use_foo_from_another_crate_without_importing_it_first() {
+    //use nice_crate_name::Foo;
+    let _: Foo<i32> = todo!(); //~ ERROR cannot find type `Foo` in this scope
+}
+
+fn main() {}

tests/ui/imports/issue-121168.stderr

@@ -0,0 +1,16 @@
+error[E0412]: cannot find type `Foo` in this scope
+  --> $DIR/issue-121168.rs:9:12
+   |
+LL |     let _: Foo<i32> = todo!();
+   |            ^^^ not found in this scope
+   |
+help: consider importing one of these items
+   |
+LL + use crate::nice_crate_name::Foo;
+   |
+LL + use issue_121168_extern::Foo;
+   |
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0412`.

tests/ui/imports/issue-56125.stderr

@@ -8,10 +8,13 @@ help: consider importing one of these items instead
    |
 LL |     use ::issue_56125::issue_56125;
    |         ~~~~~~~~~~~~~~~~~~~~~~~~~~
+LL |     use ::issue_56125::last_segment::issue_56125;
+   |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+LL |     use ::issue_56125::non_last_segment::non_last_segment::issue_56125;
+   |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 LL |     use crate::m3::last_segment::issue_56125;
    |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-LL |     use crate::m3::non_last_segment::non_last_segment::issue_56125;
-   |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+     and 1 other candidate
 
 error[E0659]: `issue_56125` is ambiguous
   --> $DIR/issue-56125.rs:6:9

tests/ui/mir/issue-106062.stderr

@@ -2,10 +2,14 @@ error[E0573]: expected type, found variant `Ok`
   --> $DIR/issue-106062.rs:15:64
    |
 LL |     async fn connection_handler(handler: impl Sized) -> Result<Ok, std::io::Error> {
-   |                                                                ^^
-   |                                                                |
-   |                                                                not a type
-   |                                                                help: try using the variant's enum: `core::result::Result`
+   |                                                                ^^ not a type
+   |
+help: try using the variant's enum
+   |
+LL |     async fn connection_handler(handler: impl Sized) -> Result<core::result::Result, std::io::Error> {
+   |                                                                ~~~~~~~~~~~~~~~~~~~~
+LL |     async fn connection_handler(handler: impl Sized) -> Result<std::result::Result, std::io::Error> {
+   |                                                                ~~~~~~~~~~~~~~~~~~~
 
 error: aborting due to 1 previous error
 

tests/ui/suggestions/core-std-import-order-issue-83564.rs

@@ -4,7 +4,7 @@
 // For some reason, Rust 2018 or higher is required to reproduce the bug.
 
 fn main() {
-    //~^ HELP consider importing this type alias
+    //~^ HELP consider importing one of these items
     let _x = NonZeroU32::new(5).unwrap();
     //~^ ERROR failed to resolve: use of undeclared type `NonZeroU32`
 }

tests/ui/suggestions/core-std-import-order-issue-83564.stderr

@@ -4,10 +4,12 @@ error[E0433]: failed to resolve: use of undeclared type `NonZeroU32`
 LL |     let _x = NonZeroU32::new(5).unwrap();
    |              ^^^^^^^^^^ use of undeclared type `NonZeroU32`
    |
-help: consider importing this type alias
+help: consider importing one of these items
    |
 LL + use core::num::NonZeroU32;
    |
+LL + use std::num::NonZeroU32;
+   |
 
 error: aborting due to 1 previous error
 

tests/ui/suggestions/crate-or-module-typo.stderr

@@ -30,10 +30,12 @@ help: there is a crate or module with a similar name
    |
 LL |     bar: std::cell::Cell<bool>
    |          ~~~
-help: consider importing this module
+help: consider importing one of these items
    |
 LL + use core::cell;
    |
+LL + use std::cell;
+   |
 help: if you import `cell`, refer to it directly
    |
 LL -     bar: st::cell::Cell<bool>

tests/ui/suggestions/suggest-tryinto-edition-change.rs

@@ -11,16 +11,19 @@ fn test() {
     let _i: i16 = TryFrom::try_from(0_i32).unwrap();
     //~^ ERROR failed to resolve: use of undeclared type
     //~| NOTE use of undeclared type
+    //~| NOTE 'std::convert::TryFrom' is included in the prelude starting in Edition 2021
     //~| NOTE 'core::convert::TryFrom' is included in the prelude starting in Edition 2021
 
     let _i: i16 = TryInto::try_into(0_i32).unwrap();
     //~^ ERROR failed to resolve: use of undeclared type
     //~| NOTE use of undeclared type
+    //~| NOTE 'std::convert::TryInto' is included in the prelude starting in Edition 2021
     //~| NOTE 'core::convert::TryInto' is included in the prelude starting in Edition 2021
 
     let _v: Vec<_> = FromIterator::from_iter(&[1]);
     //~^ ERROR failed to resolve: use of undeclared type
     //~| NOTE use of undeclared type
+    //~| NOTE 'std::iter::FromIterator' is included in the prelude starting in Edition 2021
     //~| NOTE 'core::iter::FromIterator' is included in the prelude starting in Edition 2021
 }
 

tests/ui/suggestions/suggest-tryinto-edition-change.stderr

@@ -5,38 +5,47 @@ LL |     let _i: i16 = TryFrom::try_from(0_i32).unwrap();
    |                   ^^^^^^^ use of undeclared type `TryFrom`
    |
    = note: 'core::convert::TryFrom' is included in the prelude starting in Edition 2021
-help: consider importing this trait
+   = note: 'std::convert::TryFrom' is included in the prelude starting in Edition 2021
+help: consider importing one of these items
    |
 LL + use core::convert::TryFrom;
    |
+LL + use std::convert::TryFrom;
+   |
 
 error[E0433]: failed to resolve: use of undeclared type `TryInto`
-  --> $DIR/suggest-tryinto-edition-change.rs:16:19
+  --> $DIR/suggest-tryinto-edition-change.rs:17:19
    |
 LL |     let _i: i16 = TryInto::try_into(0_i32).unwrap();
    |                   ^^^^^^^ use of undeclared type `TryInto`
    |
    = note: 'core::convert::TryInto' is included in the prelude starting in Edition 2021
-help: consider importing this trait
+   = note: 'std::convert::TryInto' is included in the prelude starting in Edition 2021
+help: consider importing one of these items
    |
 LL + use core::convert::TryInto;
    |
+LL + use std::convert::TryInto;
+   |
 
 error[E0433]: failed to resolve: use of undeclared type `FromIterator`
-  --> $DIR/suggest-tryinto-edition-change.rs:21:22
+  --> $DIR/suggest-tryinto-edition-change.rs:23:22
    |
 LL |     let _v: Vec<_> = FromIterator::from_iter(&[1]);
    |                      ^^^^^^^^^^^^ use of undeclared type `FromIterator`
    |
    = note: 'core::iter::FromIterator' is included in the prelude starting in Edition 2021
+   = note: 'std::iter::FromIterator' is included in the prelude starting in Edition 2021
 help: a trait with a similar name exists
    |
 LL |     let _v: Vec<_> = IntoIterator::from_iter(&[1]);
    |                      ~~~~~~~~~~~~
-help: consider importing this trait
+help: consider importing one of these items
    |
 LL + use core::iter::FromIterator;
    |
+LL + use std::iter::FromIterator;
+   |
 
 error[E0599]: no method named `try_into` found for type `i32` in the current scope
   --> $DIR/suggest-tryinto-edition-change.rs:6:25