From a42afa0444118ae5549f89e8ea9a15b73702fbcf Mon Sep 17 00:00:00 2001
From: Rejyr <jerrylwang123@gmail.com>
Date: Mon, 5 Sep 2022 11:52:08 -0400
Subject: [PATCH] migrate: `traits.rs`

---
 compiler/rustc_lint/src/lints.rs  | 30 +++++++++++++++++++++++++++++-
 compiler/rustc_lint/src/traits.rs | 27 ++++++++++++---------------
 2 files changed, 41 insertions(+), 16 deletions(-)

diff --git a/compiler/rustc_lint/src/lints.rs b/compiler/rustc_lint/src/lints.rs
index c68bfc98f93..691cc8667e3 100644
--- a/compiler/rustc_lint/src/lints.rs
+++ b/compiler/rustc_lint/src/lints.rs
@@ -1,11 +1,39 @@
 use rustc_errors::{fluent, AddSubdiagnostic, Applicability, DecorateLint, EmissionGuarantee};
 use rustc_hir::def_id::DefId;
 use rustc_macros::{LintDiagnostic, SessionSubdiagnostic};
-use rustc_middle::ty::Ty;
+use rustc_middle::ty::{Predicate, Ty, TyCtxt};
 use rustc_span::{Span, Symbol};
 
 use crate::LateContext;
 
+pub struct DropTraitConstraintsDiag<'a> {
+    pub predicate: Predicate<'a>,
+    pub tcx: TyCtxt<'a>,
+    pub def_id: DefId,
+}
+
+impl<'a, G: EmissionGuarantee> DecorateLint<'_, G> for DropTraitConstraintsDiag<'a> {
+    fn decorate_lint(self, diag: rustc_errors::LintDiagnosticBuilder<'_, G>) {
+        let mut diag = diag.build(fluent::lint_drop_trait_constraints);
+        diag.set_arg("predicate", self.predicate);
+        diag.set_arg("needs_drop", self.tcx.def_path_str(self.def_id));
+        diag.emit();
+    }
+}
+
+pub struct DropGlue<'a> {
+    pub tcx: TyCtxt<'a>,
+    pub def_id: DefId,
+}
+
+impl<'a, G: EmissionGuarantee> DecorateLint<'_, G> for DropGlue<'a> {
+    fn decorate_lint(self, diag: rustc_errors::LintDiagnosticBuilder<'_, G>) {
+        let mut diag = diag.build(fluent::lint_drop_glue);
+        diag.set_arg("needs_drop", self.tcx.def_path_str(self.def_id));
+        diag.emit();
+    }
+}
+
 #[derive(LintDiagnostic)]
 #[diag(lint_range_endpoint_out_of_range)]
 pub struct RangeEndpointOutOfRange<'a> {
diff --git a/compiler/rustc_lint/src/traits.rs b/compiler/rustc_lint/src/traits.rs
index 1b21c2dac37..2e778cf0d0f 100644
--- a/compiler/rustc_lint/src/traits.rs
+++ b/compiler/rustc_lint/src/traits.rs
@@ -1,7 +1,9 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
+use crate::lints::{DropGlue, DropTraitConstraintsDiag};
 use crate::LateContext;
 use crate::LateLintPass;
 use crate::LintContext;
-use rustc_errors::fluent;
 use rustc_hir as hir;
 use rustc_span::symbol::sym;
 
@@ -101,17 +103,13 @@ impl<'tcx> LateLintPass<'tcx> for DropTraitConstraints {
                 if trait_predicate.trait_ref.self_ty().is_impl_trait() {
                     continue;
                 }
-                let Some(needs_drop) = cx.tcx.get_diagnostic_item(sym::needs_drop) else {
-                    continue;
+                let Some(def_id) = cx.tcx.get_diagnostic_item(sym::needs_drop) else {
+                    return
                 };
-                cx.struct_span_lint(
+                cx.emit_spanned_lint(
                     DROP_BOUNDS,
                     span,
-                    fluent::lint_drop_trait_constraints,
-                    |lint| {
-                        lint.set_arg("predicate", predicate)
-                            .set_arg("needs_drop", cx.tcx.def_path_str(needs_drop))
-                    },
+                    DropTraitConstraintsDiag { predicate, tcx: cx.tcx, def_id },
                 );
             }
         }
@@ -123,12 +121,11 @@ impl<'tcx> LateLintPass<'tcx> for DropTraitConstraints {
         };
         for bound in &bounds[..] {
             let def_id = bound.trait_ref.trait_def_id();
-            if cx.tcx.lang_items().drop_trait() == def_id
-                && let Some(needs_drop) = cx.tcx.get_diagnostic_item(sym::needs_drop)
-            {
-                cx.struct_span_lint(DYN_DROP, bound.span, fluent::lint_drop_glue, |lint| {
-                    lint.set_arg("needs_drop", cx.tcx.def_path_str(needs_drop))
-                });
+            if cx.tcx.lang_items().drop_trait() == def_id {
+                let Some(def_id) = cx.tcx.get_diagnostic_item(sym::needs_drop) else {
+                    return
+                };
+                cx.emit_spanned_lint(DYN_DROP, bound.span, DropGlue { tcx: cx.tcx, def_id });
             }
         }
     }