lint: port no-op method call diagnostics

Signed-off-by: David Wood <[email protected]>

Author: davidtwco

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

@@ -124,3 +124,7 @@ lint-non-snake-case = {$sort} `{$name}` should have a snake case name
 lint-non-upper_case-global = {$sort} `{$name}` should have an upper case name
     .suggestion = convert the identifier to upper case
     .label = should have an UPPER_CASE name
+
+lint-noop-method-call = call to `.{$method}()` on a reference in this situation does nothing
+    .label = unnecessary method call
+    .note = the type `{$receiver_ty}` which `{$method}` is being called on is the same as the type returned from `{$method}`, so the method call does not do anything and can be removed

compiler/rustc_lint/src/noop_method_call.rs

@@ -2,6 +2,7 @@ use crate::context::LintContext;
 use crate::rustc_middle::ty::TypeFoldable;
 use crate::LateContext;
 use crate::LateLintPass;
+use rustc_errors::fluent;
 use rustc_hir::def::DefKind;
 use rustc_hir::{Expr, ExprKind};
 use rustc_middle::ty;
@@ -80,7 +81,6 @@ impl<'tcx> LateLintPass<'tcx> for NoopMethodCall {
         ) {
             return;
         }
-        let method = &call.ident.name;
         let receiver = &elements[0];
         let receiver_ty = cx.typeck_results().expr_ty(receiver);
         let expr_ty = cx.typeck_results().expr_ty_adjusted(expr);
@@ -90,19 +90,14 @@ impl<'tcx> LateLintPass<'tcx> for NoopMethodCall {
             return;
         }
         let expr_span = expr.span;
-        let note = format!(
-            "the type `{:?}` which `{}` is being called on is the same as \
-             the type returned from `{}`, so the method call does not do \
-             anything and can be removed",
-            receiver_ty, method, method,
-        );
-
         let span = expr_span.with_lo(receiver.span.hi());
         cx.struct_span_lint(NOOP_METHOD_CALL, span, |lint| {
-            let method = &call.ident.name;
-            let message =
-                format!("call to `.{}()` on a reference in this situation does nothing", &method,);
-            lint.build(&message).span_label(span, "unnecessary method call").note(&note).emit();
+            lint.build(fluent::lint::noop_method_call)
+                .set_arg("method", call.ident.name)
+                .set_arg("receiver_ty", receiver_ty)
+                .span_label(span, fluent::lint::label)
+                .note(fluent::lint::note)
+                .emit();
         });
     }
 }