Add translatable diagnostic for changing import binding

Author: NotStirred

compiler/rustc_resolve/messages.ftl

@@ -262,3 +262,6 @@ resolve_variable_bound_with_different_mode =
     variable `{$variable_name}` is bound inconsistently across alternatives separated by `|`
     .label = bound in different ways
     .first_binding_span = first binding
+
+resolve_change_import_binding =
+    you can use `as` to change the binding name of the import

compiler/rustc_resolve/src/diagnostics.rs

@@ -30,6 +30,7 @@ use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{BytePos, Span, SyntaxContext};
 use thin_vec::ThinVec;
 
+use crate::errors::{ChangeImportBinding, ChangeImportBindingSuggestion};
 use crate::imports::{Import, ImportKind};
 use crate::late::{PatternSource, Rib};
 use crate::path_names_to_string;
@@ -376,16 +377,10 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             _ => unreachable!(),
         }
 
-        let rename_msg = "you can use `as` to change the binding name of the import";
         if let Some(suggestion) = suggestion {
-            err.span_suggestion(
-                binding_span,
-                rename_msg,
-                suggestion,
-                Applicability::MaybeIncorrect,
-            );
+            err.subdiagnostic(ChangeImportBindingSuggestion { span: binding_span, suggestion });
         } else {
-            err.span_label(binding_span, rename_msg);
+            err.subdiagnostic(ChangeImportBinding { span: binding_span });
         }
     }
 

compiler/rustc_resolve/src/errors.rs

@@ -586,3 +586,22 @@ pub(crate) enum ParamKindInEnumDiscriminant {
     #[note(resolve_lifetime_param_in_enum_discriminant)]
     Lifetime,
 }
+
+#[derive(Subdiagnostic)]
+#[label(resolve_change_import_binding)]
+pub(crate) struct ChangeImportBinding {
+    #[primary_span]
+    pub(crate) span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(
+    resolve_change_import_binding,
+    code = "{suggestion}",
+    applicability = "maybe-incorrect"
+)]
+pub(crate) struct ChangeImportBindingSuggestion {
+    #[primary_span]
+    pub(crate) span: Span,
+    pub(crate) suggestion: String,
+}