Clean up let_unit_value changes

Author: scottgerring

clippy_lints/src/unit_types/let_unit_value.rs

@@ -80,7 +80,8 @@ pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, local: &'tcx LetStmt<'_>) {
                         suggestions.push((local.span, format!("{snip};")));
                     }
 
-                    // Check if this is a binding pattern
+                    // If this is a binding pattern, we need to add suggestions to remove any usages
+                    // of the variable
                     if let PatKind::Binding(_, binding_hir_id, ident, ..) = local.pat.kind {
                         if let Some(body_id) = cx.enclosing_body.as_ref() {
                             let body = cx.tcx.hir().body(*body_id);
@@ -94,29 +95,22 @@ pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, local: &'tcx LetStmt<'_>) {
                             if has_usages {
                                 suggestions.extend(visitor.spans.into_iter().map(|span| (span, "()".to_string())));
                             }
-
-                            // Emit appropriate diagnostic based on whether there are usages
-                            if has_usages {
-                                diag.multipart_suggestion(
-                                    "omit the `let` binding and replace variable usages with `()`",
-                                    suggestions,
-                                    Applicability::MachineApplicable,
-                                );
-                            } else {
-                                diag.multipart_suggestion(
-                                    "omit the `let` binding",
-                                    suggestions,
-                                    Applicability::MachineApplicable,
-                                );
-                            }
                         }
-                    } else {
-                        // Emit a simpler diagnostic if not a binding
+                    }
+
+                    // Emit appropriate diagnostic based on whether there are usages of the let binding
+                    if suggestions.len() == 1 {
                         diag.multipart_suggestion(
                             "omit the `let` binding",
                             suggestions,
                             Applicability::MachineApplicable,
                         );
+                    } else if suggestions.len() > 1 {
+                        diag.multipart_suggestion(
+                            "omit the `let` binding and replace variable usages with `()`",
+                            suggestions,
+                            Applicability::MachineApplicable,
+                        );
                     }
                 },
             );