Make E0599 a structured error

compiler/rustc_hir_analysis/messages.ftl

@@ -387,6 +387,8 @@ hir_analysis_must_implement_not_function_span_note = required by this annotation
 
 hir_analysis_must_implement_one_of_attribute = the `#[rustc_must_implement_one_of]` attribute must be used with at least 2 args
 
+hir_analysis_no_variant_named = no variant named `{$ident}` found for enum `{$ty}`
+
 hir_analysis_not_supported_delegation = {$descr}
     .label = callee defined here
 

compiler/rustc_hir_analysis/src/errors.rs

@@ -1417,6 +1417,15 @@ pub(crate) struct CrossCrateTraitsDefined {
     pub traits: String,
 }
 
+#[derive(Diagnostic)]
+#[diag(hir_analysis_no_variant_named, code = E0599)]
+pub struct NoVariantNamed<'tcx> {
+    #[primary_span]
+    pub span: Span,
+    pub ident: Ident,
+    pub ty: Ty<'tcx>,
+}
+
 // FIXME(fmease): Deduplicate:
 
 #[derive(Diagnostic)]

compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs

@@ -53,7 +53,9 @@ use tracing::{debug, instrument};
 
 use crate::bounds::Bounds;
 use crate::check::check_abi_fn_ptr;
-use crate::errors::{AmbiguousLifetimeBound, BadReturnTypeNotation, InvalidBaseType};
+use crate::errors::{
+    AmbiguousLifetimeBound, BadReturnTypeNotation, InvalidBaseType, NoVariantNamed,
+};
 use crate::hir_ty_lowering::errors::{GenericsArgsErrExtend, prohibit_assoc_item_constraint};
 use crate::hir_ty_lowering::generics::{check_generic_arg_count, lower_generic_args};
 use crate::middle::resolve_bound_vars as rbv;
@@ -1188,14 +1190,11 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
                     let msg = format!("expected type, found variant `{assoc_ident}`");
                     self.dcx().span_err(span, msg)
                 } else if qself_ty.is_enum() {
-                    let mut err = struct_span_code_err!(
-                        self.dcx(),
-                        assoc_ident.span,
-                        E0599,
-                        "no variant named `{}` found for enum `{}`",
-                        assoc_ident,
-                        qself_ty,
-                    );
+                    let mut err = self.dcx().create_err(NoVariantNamed {
+                        span: assoc_ident.span,
+                        ident: assoc_ident,
+                        ty: qself_ty,
+                    });
 
                     let adt_def = qself_ty.ty_adt_def().expect("enum is not an ADT");
                     if let Some(variant_name) = find_best_match_for_name(

compiler/rustc_hir_analysis/src/lib.rs

@@ -93,6 +93,7 @@ mod impl_wf_check;
 mod outlives;
 mod variance;
 
+pub use errors::NoVariantNamed;
 use rustc_abi::ExternAbi;
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;

compiler/rustc_hir_typeck/src/expr.rs

@@ -19,6 +19,7 @@ use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::Visitor;
 use rustc_hir::lang_items::LangItem;
 use rustc_hir::{ExprKind, HirId, QPath};
+use rustc_hir_analysis::NoVariantNamed;
 use rustc_hir_analysis::hir_ty_lowering::{FeedConstTy, HirTyLowerer as _};
 use rustc_infer::infer;
 use rustc_infer::infer::{DefineOpaqueTypes, InferOk};
@@ -3837,15 +3838,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         .iter_enumerated()
                         .find(|(_, v)| v.ident(self.tcx).normalize_to_macros_2_0() == ident)
                     else {
-                        type_error_struct!(
-                            self.dcx(),
-                            ident.span,
-                            container,
-                            E0599,
-                            "no variant named `{ident}` found for enum `{container}`",
-                        )
-                        .with_span_label(field.span, "variant not found")
-                        .emit();
+                        self.dcx()
+                            .create_err(NoVariantNamed { span: ident.span, ident, ty: container })
+                            .with_span_label(field.span, "variant not found")
+                            .emit_unless(container.references_error());
                         break;
                     };
                     let Some(&subfield) = fields.next() else {