Add an additional help note to the ambiguity lint error

This PR adds an additional help note to the ambiguity lint error output
to ask users updating their dependencies. This hopefully helps with
cases like https://github.com/rust-lang/rust/issues/149845 where newer crate versions are fixed.

compiler/rustc_resolve/src/diagnostics.rs

@@ -2064,9 +2064,24 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
         };
         let (b1_note, b1_help_msgs) = could_refer_to(b1, scope1, "");
         let (b2_note, b2_help_msgs) = could_refer_to(b2, scope2, " also");
+        let help = if kind == AmbiguityKind::GlobVsGlob
+            && b1
+                .parent_module
+                .and_then(|m| m.opt_def_id())
+                .map(|d| !d.is_local())
+                .unwrap_or_default()
+        {
+            Some(&[
+                "consider updating this dependency to resolve this error",
+                "if updating the dependency does not resolve the problem report the problem to the author of the relevant crate",
+            ] as &[_])
+        } else {
+            None
+        };
 
         errors::Ambiguity {
             ident,
+            help,
             kind: kind.descr(),
             b1_note,
             b1_help_msgs,

compiler/rustc_resolve/src/errors.rs

@@ -1464,6 +1464,7 @@ pub(crate) struct UnknownDiagnosticAttributeTypoSugg {
 pub(crate) struct Ambiguity {
     pub ident: Ident,
     pub kind: &'static str,
+    pub help: Option<&'static [&'static str]>,
     pub b1_note: Spanned<String>,
     pub b1_help_msgs: Vec<String>,
     pub b2_note: Spanned<String>,
@@ -1476,6 +1477,11 @@ impl Ambiguity {
         diag.span_label(self.ident.span, "ambiguous name");
         diag.note(format!("ambiguous because of {}", self.kind));
         diag.span_note(self.b1_note.span, self.b1_note.node);
+        if let Some(help) = self.help {
+            for help in help {
+                diag.help(*help);
+            }
+        }
         for help_msg in self.b1_help_msgs {
             diag.help(help_msg);
         }

tests/ui/imports/ambiguous-2.stderr

@@ -12,6 +12,8 @@ note: `id` could refer to the function defined here
    |
 LL |     pub use self::evp::*;
    |             ^^^^^^^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `id` could also refer to the function defined here
   --> $DIR/auxiliary/../ambiguous-1.rs:15:13
    |
@@ -36,6 +38,8 @@ note: `id` could refer to the function defined here
    |
 LL |     pub use self::evp::*;
    |             ^^^^^^^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `id` could also refer to the function defined here
   --> $DIR/auxiliary/../ambiguous-1.rs:15:13
    |

tests/ui/imports/ambiguous-4.stderr

@@ -12,6 +12,8 @@ note: `id` could refer to the function defined here
    |
 LL | pub use evp::*;
    |         ^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `id` could also refer to the function defined here
   --> $DIR/auxiliary/../ambiguous-4-extern.rs:14:9
    |
@@ -36,6 +38,8 @@ note: `id` could refer to the function defined here
    |
 LL | pub use evp::*;
    |         ^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `id` could also refer to the function defined here
   --> $DIR/auxiliary/../ambiguous-4-extern.rs:14:9
    |

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

@@ -12,6 +12,8 @@ note: `f` could refer to the function defined here
    |
 LL | pub use m1::*;
    |         ^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `f` could also refer to the function defined here
   --> $DIR/auxiliary/glob-conflict.rs:13:9
    |
@@ -33,6 +35,8 @@ note: `f` could refer to the function defined here
    |
 LL | pub use m1::*;
    |         ^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `f` could also refer to the function defined here
   --> $DIR/auxiliary/glob-conflict.rs:13:9
    |
@@ -56,6 +60,8 @@ note: `f` could refer to the function defined here
    |
 LL | pub use m1::*;
    |         ^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `f` could also refer to the function defined here
   --> $DIR/auxiliary/glob-conflict.rs:13:9
    |
@@ -78,6 +84,8 @@ note: `f` could refer to the function defined here
    |
 LL | pub use m1::*;
    |         ^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `f` could also refer to the function defined here
   --> $DIR/auxiliary/glob-conflict.rs:13:9
    |

tests/ui/imports/glob-conflict-cross-crate-2.stderr

@@ -12,6 +12,8 @@ note: `C` could refer to the type alias defined here
    |
 LL | pub use a::*;
    |         ^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `C` could also refer to the type alias defined here
   --> $DIR/auxiliary/glob-conflict-cross-crate-2-extern.rs:10:9
    |
@@ -36,6 +38,8 @@ note: `C` could refer to the type alias defined here
    |
 LL | pub use a::*;
    |         ^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `C` could also refer to the type alias defined here
   --> $DIR/auxiliary/glob-conflict-cross-crate-2-extern.rs:10:9
    |

tests/ui/imports/glob-conflict-cross-crate-3.stderr

@@ -12,6 +12,8 @@ note: `C` could refer to the type alias defined here
    |
 LL | pub use a::*;
    |         ^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `C` could also refer to the type alias defined here
   --> $DIR/auxiliary/glob-conflict-cross-crate-2-extern.rs:10:9
    |
@@ -58,6 +60,8 @@ note: `C` could refer to the type alias defined here
    |
 LL | pub use a::*;
    |         ^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `C` could also refer to the type alias defined here
   --> $DIR/auxiliary/glob-conflict-cross-crate-2-extern.rs:10:9
    |

tests/ui/imports/issue-114682-2.stderr

@@ -12,6 +12,8 @@ note: `max` could refer to the type alias defined here
    |
 LL | pub use self::e::*;
    |         ^^^^^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `max` could also refer to the module defined here
   --> $DIR/auxiliary/issue-114682-2-extern.rs:16:9
    |
@@ -33,6 +35,8 @@ note: `max` could refer to the type alias defined here
    |
 LL | pub use self::e::*;
    |         ^^^^^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `max` could also refer to the module defined here
   --> $DIR/auxiliary/issue-114682-2-extern.rs:16:9
    |
@@ -56,6 +60,8 @@ note: `max` could refer to the type alias defined here
    |
 LL | pub use self::e::*;
    |         ^^^^^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `max` could also refer to the module defined here
   --> $DIR/auxiliary/issue-114682-2-extern.rs:16:9
    |
@@ -78,6 +84,8 @@ note: `max` could refer to the type alias defined here
    |
 LL | pub use self::e::*;
    |         ^^^^^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `max` could also refer to the module defined here
   --> $DIR/auxiliary/issue-114682-2-extern.rs:16:9
    |

tests/ui/imports/issue-114682-4.stderr

@@ -12,6 +12,8 @@ note: `Result` could refer to the type alias defined here
    |
 LL | pub use a::*;
    |         ^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `Result` could also refer to the type alias defined here
   --> $DIR/auxiliary/issue-114682-4-extern.rs:10:9
    |
@@ -51,6 +53,8 @@ note: `Result` could refer to the type alias defined here
    |
 LL | pub use a::*;
    |         ^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `Result` could also refer to the type alias defined here
   --> $DIR/auxiliary/issue-114682-4-extern.rs:10:9
    |

tests/ui/imports/issue-114682-5.stderr

@@ -40,6 +40,8 @@ note: `issue_114682_5_extern_1` could refer to the module defined here
    |
 LL |     pub use crate::types::*;
    |             ^^^^^^^^^^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `issue_114682_5_extern_1` could also refer to the crate defined here
   --> $DIR/auxiliary/issue-114682-5-extern-2.rs:7:13
    |
@@ -67,6 +69,8 @@ note: `issue_114682_5_extern_1` could refer to the module defined here
    |
 LL |     pub use crate::types::*;
    |             ^^^^^^^^^^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `issue_114682_5_extern_1` could also refer to the crate defined here
   --> $DIR/auxiliary/issue-114682-5-extern-2.rs:7:13
    |

tests/ui/imports/issue-114682-6.stderr

@@ -12,6 +12,8 @@ note: `log` could refer to the function defined here
    |
 LL | pub use self::a::*;
    |         ^^^^^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `log` could also refer to the function defined here
   --> $DIR/auxiliary/issue-114682-6-extern.rs:9:9
    |
@@ -36,6 +38,8 @@ note: `log` could refer to the function defined here
    |
 LL | pub use self::a::*;
    |         ^^^^^^^
+   = help: consider updating this dependency to resolve this error
+   = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
 note: `log` could also refer to the function defined here
   --> $DIR/auxiliary/issue-114682-6-extern.rs:9:9
    |