tweak removal span

Author: compiler-errors

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -1596,8 +1596,15 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                 // Peel off the DesugaringKind from the span
                 && let Some(desugar_parent_span) = parent_expr.span.parent_callsite()
             {
+                let removal_span = self.tcx
+                    .sess
+                    .source_map()
+                    .span_extend_while(expr.span, char::is_whitespace)
+                    .unwrap_or(expr.span)
+                    .shrink_to_hi()
+                    .to(desugar_parent_span);
                 err.span_suggestion(
-                    self.tcx.sess.source.shrink_to_hi().to(desugar_parent_span),
+                    removal_span,
                     "remove the `.await`",
                     "",
                     Applicability::MachineApplicable,

tests/ui/async-await/issue-101715.stderr

@@ -1,13 +1,11 @@
 error[E0277]: `()` is not a future
   --> $DIR/issue-101715.rs:11:10
    |
-LL |       S.very_long_method_name_the_longest_method_name_in_the_whole_universe()
-   |  ____________________________________________________________________________-
-LL | |         .await
-   | |          ^^^^-
-   | |__________|___|
-   |            |   help: remove the `.await`
-   |            `()` is not a future
+LL |         .await
+   |         -^^^^^
+   |         ||
+   |         |`()` is not a future
+   |         help: remove the `.await`
    |
    = help: the trait `Future` is not implemented for `()`
    = note: () must be a future or must implement `IntoFuture` to be awaited