internal: simplify the process of inserting spaces after mut

Author: roife

crates/ide-assists/src/handlers/inline_call.rs

@@ -415,24 +415,16 @@ fn inline(
  let expr: &ast::Expr = expr;
 
  let mut insert_let_stmt = || {
- let param_ty = match param_ty {
- None => None,
- Some(param_ty) => {
- if sema.hir_file_for(param_ty.syntax()).is_macro() {
- if let Some(param_ty) =
- ast::Type::cast(insert_ws_into(param_ty.syntax().clone()))
- {
- Some(param_ty)
- } else {
- Some(param_ty.clone_for_update())
- }
- } else {
- Some(param_ty.clone_for_update())
- }
+ let param_ty = param_ty.clone().map(|param_ty| {
+ if sema.hir_file_for(param_ty.syntax()).is_macro() {
+ ast::Type::cast(insert_ws_into(param_ty.syntax().clone()))
+ .unwrap_or_else(|| param_ty)
+ } else {
+ param_ty
  }
- };
- let ty: Option<syntax::ast::Type> =
-   sema.type_of_expr(expr).filter(TypeInfo::has_adjustment).and(param_ty);
+ });
+
+ let ty = sema.type_of_expr(expr).filter(TypeInfo::has_adjustment).and(param_ty);
 
  let is_self = param
  .name(sema.db)