disallow ambiguous names imported from external crates

Author: LorrensP-2158466

compiler/rustc_resolve/src/imports.rs

@@ -1653,8 +1653,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
 
         module.for_each_child(self, |this, ident, _, binding| {
             let res = binding.res().expect_non_local();
-            let error_ambiguity = binding.is_ambiguity_recursive() && !binding.warn_ambiguity;
-            if res != def::Res::Err && !error_ambiguity {
+            if res != def::Res::Err && !binding.is_ambiguity_recursive() {
                 let mut reexport_chain = SmallVec::new();
                 let mut next_binding = binding;
                 while let NameBindingKind::Import { binding, import, .. } = next_binding.kind {

tests/ui/imports/ambiguous-2.rs

@@ -1,10 +1,9 @@
-//@ check-pass
 //@ aux-build: ../ambiguous-1.rs
 // https://github.com/rust-lang/rust/pull/113099#issuecomment-1633574396
 
 extern crate ambiguous_1;
 
 fn main() {
-    ambiguous_1::id();
+    ambiguous_1::id(); //~ ERROR cannot find function `id` in crate `ambiguous_1`
     //^ FIXME: `id` should be identified as an ambiguous item.
 }

tests/ui/imports/ambiguous-2.stderr

@@ -0,0 +1,19 @@
+error[E0425]: cannot find function `id` in crate `ambiguous_1`
+  --> $DIR/ambiguous-2.rs:7:18
+   |
+LL |     ambiguous_1::id();
+   |                  ^^ not found in `ambiguous_1`
+   |
+help: consider importing this function
+   |
+LL + use std::process::id;
+   |
+help: if you import `id`, refer to it directly
+   |
+LL -     ambiguous_1::id();
+LL +     id();
+   |
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0425`.

tests/ui/imports/ambiguous-4.rs

@@ -1,9 +1,8 @@
-//@ check-pass
 //@ aux-build: ../ambiguous-4-extern.rs
 
 extern crate ambiguous_4_extern;
 
 fn main() {
-    ambiguous_4_extern::id();
+    ambiguous_4_extern::id(); //~ ERROR cannot find function `id` in crate `ambiguous_4_extern`
     //^ FIXME: `id` should be identified as an ambiguous item.
 }

tests/ui/imports/ambiguous-4.stderr

@@ -0,0 +1,19 @@
+error[E0425]: cannot find function `id` in crate `ambiguous_4_extern`
+  --> $DIR/ambiguous-4.rs:6:25
+   |
+LL |     ambiguous_4_extern::id();
+   |                         ^^ not found in `ambiguous_4_extern`
+   |
+help: consider importing this function
+   |
+LL + use std::process::id;
+   |
+help: if you import `id`, refer to it directly
+   |
+LL -     ambiguous_4_extern::id();
+LL +     id();
+   |
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0425`.

tests/ui/imports/glob-conflict-cross-crate-1.rs

@@ -6,7 +6,7 @@ fn main() {
     glob_conflict::f(); //~ ERROR cannot find function `f` in crate `glob_conflict`
     //^ FIXME: `glob_conflict::f` should raise an
     // ambiguity error instead of a not found error.
-    glob_conflict::glob::f();
+    glob_conflict::glob::f(); //~ ERROR cannot find function `f` in module `glob_conflict::glob`
     //^ FIXME: `glob_conflict::glob::f` should raise an
     // ambiguity error instead of a not found error.
 }

tests/ui/imports/glob-conflict-cross-crate-1.stderr

@@ -3,17 +3,13 @@ error[E0425]: cannot find function `f` in crate `glob_conflict`
    |
 LL |     glob_conflict::f();
    |                    ^ not found in `glob_conflict`
+
+error[E0425]: cannot find function `f` in module `glob_conflict::glob`
+  --> $DIR/glob-conflict-cross-crate-1.rs:9:26
    |
-help: consider importing this function
-   |
-LL + use glob_conflict::glob::f;
-   |
-help: if you import `f`, refer to it directly
-   |
-LL -     glob_conflict::f();
-LL +     f();
-   |
+LL |     glob_conflict::glob::f();
+   |                          ^ not found in `glob_conflict::glob`
 
-error: aborting due to 1 previous error
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0425`.