avoid string dispatch in fluent

Author: CleanCut

compiler/rustc_error_messages/locales/en-US/passes.ftl

@@ -533,11 +533,27 @@ passes_no_main_function =
     .non_function_main = non-function item at `crate::main` is found
 
 passes_duplicate_lang_item =
-    {$message ->
-        *[duplicate] found duplicate lang item `{$lang_item_name}`
-        [duplicate_in_crate] duplicate lang item in crate `{$crate_name}`: `{$lang_item_name}`.
-        [duplicate_in_crate_depends] duplicate lang item in crate `{$crate_name}` (which `{$dependency_of}` depends on): `{$lang_item_name}`.
-    }
+    found duplicate lang item `{$lang_item_name}`
+    .first_defined_span = the lang item is first defined here
+    .first_defined_crate_depends = the lang item is first defined in crate `{$orig_crate_name}` (which `{$orig_dependency_of}` depends on)
+    .first_defined_crate = the lang item is first defined in crate `{$orig_crate_name}`.
+    .first_definition_local = first definition in the local crate (`{$orig_crate_name}`)
+    .second_definition_local = second definition in the local crate (`{$crate_name}`)
+    .first_definition_path = first definition in `{$orig_crate_name}` loaded from {$orig_path}
+    .second_definition_path = second definition in `{$crate_name}` loaded from {$path}
+
+passes_duplicate_lang_item_crate =
+    duplicate lang item in crate `{$crate_name}`: `{$lang_item_name}`.
+    .first_defined_span = the lang item is first defined here
+    .first_defined_crate_depends = the lang item is first defined in crate `{$orig_crate_name}` (which `{$orig_dependency_of}` depends on)
+    .first_defined_crate = the lang item is first defined in crate `{$orig_crate_name}`.
+    .first_definition_local = first definition in the local crate (`{$orig_crate_name}`)
+    .second_definition_local = second definition in the local crate (`{$crate_name}`)
+    .first_definition_path = first definition in `{$orig_crate_name}` loaded from {$orig_path}
+    .second_definition_path = second definition in `{$crate_name}` loaded from {$path}
+
+passes_duplicate_lang_item_crate_depends =
+    duplicate lang item in crate `{$crate_name}` (which `{$dependency_of}` depends on): `{$lang_item_name}`.
     .first_defined_span = the lang item is first defined here
     .first_defined_crate_depends = the lang item is first defined in crate `{$orig_crate_name}` (which `{$orig_dependency_of}` depends on)
     .first_defined_crate = the lang item is first defined in crate `{$orig_crate_name}`.

compiler/rustc_passes/src/errors.rs

@@ -10,6 +10,8 @@ use rustc_macros::{Diagnostic, LintDiagnostic, Subdiagnostic};
 use rustc_middle::ty::{MainDefinition, Ty};
 use rustc_span::{Span, Symbol, DUMMY_SP};
 
+use crate::lang_items::Duplicate;
+
 #[derive(LintDiagnostic)]
 #[diag(passes::outer_crate_level_attr)]
 pub struct OuterCrateLevelAttr;
@@ -1175,7 +1177,7 @@ impl<'a> IntoDiagnostic<'a> for NoMainErr {
     }
 }
 
-pub struct DuplicateLangItem<'a> {
+pub struct DuplicateLangItem {
     pub local_span: Option<Span>,
     pub lang_item_name: Symbol,
     pub crate_name: Symbol,
@@ -1187,16 +1189,23 @@ pub struct DuplicateLangItem<'a> {
     pub orig_dependency_of: Symbol,
     pub orig_is_local: bool,
     pub orig_path: String,
-    pub message: &'a str,
+    pub(crate) duplicate: Duplicate,
 }
 
-impl<'a, 'b> IntoDiagnostic<'a> for DuplicateLangItem<'b> {
+impl IntoDiagnostic<'_> for DuplicateLangItem {
     fn into_diagnostic(
         self,
-        handler: &'a rustc_errors::Handler,
-    ) -> rustc_errors::DiagnosticBuilder<'a, ErrorGuaranteed> {
+        handler: &rustc_errors::Handler,
+    ) -> rustc_errors::DiagnosticBuilder<'_, ErrorGuaranteed> {
         let mut diag = handler.struct_err_with_code(
-            rustc_errors::fluent::passes::duplicate_lang_item,
+            match self.duplicate {
+                Duplicate::Plain => rustc_errors::fluent::passes::duplicate_lang_item,
+
+                Duplicate::Crate => rustc_errors::fluent::passes::duplicate_lang_item_crate,
+                Duplicate::CrateDepends => {
+                    rustc_errors::fluent::passes::duplicate_lang_item_crate_depends
+                }
+            },
             error_code!(E0152),
         );
         diag.set_arg("lang_item_name", self.lang_item_name);
@@ -1206,7 +1215,6 @@ impl<'a, 'b> IntoDiagnostic<'a> for DuplicateLangItem<'b> {
         diag.set_arg("orig_crate_name", self.orig_crate_name);
         diag.set_arg("orig_dependency_of", self.orig_dependency_of);
         diag.set_arg("orig_path", self.orig_path);
-        diag.set_arg("message", self.message);
         if let Some(span) = self.local_span {
             diag.set_span(span);
         }

compiler/rustc_passes/src/lang_items.rs

@@ -24,6 +24,12 @@ use rustc_span::{symbol::kw::Empty, Span};
 
 use rustc_middle::ty::query::Providers;
 
+pub(crate) enum Duplicate {
+    Plain,
+    Crate,
+    CrateDepends,
+}
+
 struct LanguageItemCollector<'tcx> {
     items: LanguageItems,
     tcx: TyCtxt<'tcx>,
@@ -103,15 +109,15 @@ impl<'tcx> LanguageItemCollector<'tcx> {
                     }
                 }
 
-                let message = if local_span.is_some() {
-                    "duplicate"
+                let duplicate = if local_span.is_some() {
+                    Duplicate::Plain
                 } else {
                     match self.tcx.extern_crate(item_def_id) {
                         Some(ExternCrate { dependency_of: inner_dependency_of, .. }) => {
                             dependency_of = self.tcx.crate_name(*inner_dependency_of);
-                            "duplicate_in_crate_depends"
+                            Duplicate::CrateDepends
                         }
-                        _ => "duplicate_in_crate",
+                        _ => Duplicate::Crate,
                     }
                 };
 
@@ -127,7 +133,7 @@ impl<'tcx> LanguageItemCollector<'tcx> {
                     orig_dependency_of,
                     orig_is_local,
                     orig_path,
-                    message,
+                    duplicate,
                 });
             }
         }