implement feedback from review

Author: yoshuawuyts

crates/ide_assists/src/utils/gen_trait_fn_body.rs

@@ -154,29 +154,27 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
 
                 match variant.field_list() {
                     Some(ast::FieldList::RecordFieldList(list)) => {
-                        let mut pats = vec![];
-
                         // => f.debug_struct(name)
                         let target = make::expr_path(make::ext::ident_path("f"));
                         let method = make::name_ref("debug_struct");
                         let struct_name = format!("\"{}\"", name);
                         let args = make::arg_list(Some(make::expr_literal(&struct_name).into()));
                         let mut expr = make::expr_method_call(target, method, args);
 
+                        let mut pats = vec![];
                         for field in list.fields() {
-                            let name = field.name()?;
+                            let field_name = field.name()?;
 
                             // create a field pattern for use in `MyStruct { fields.. }`
-                            let field_name = field.name()?;
                             let pat = make::ident_pat(false, false, field_name.clone());
                             pats.push(pat.into());
 
                             // => <expr>.field("field_name", field)
                             let method_name = make::name_ref("field");
-                            let field_name = make::expr_literal(&(format!("\"{}\"", name))).into();
-                            let field_path = &format!("{}", name);
-                            let field_path = make::expr_path(make::ext::ident_path(field_path));
-                            let args = make::arg_list(vec![field_name, field_path]);
+                            let name = make::expr_literal(&(format!("\"{}\"", field_name))).into();
+                            let path = &format!("{}", field_name);
+                            let path = make::expr_path(make::ext::ident_path(path));
+                            let args = make::arg_list(vec![name, path]);
                             expr = make::expr_method_call(expr, method_name, args);
                         }
 
@@ -189,15 +187,14 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                         arms.push(make::match_arm(Some(pat.into()), None, expr));
                     }
                     Some(ast::FieldList::TupleFieldList(list)) => {
-                        let mut pats = vec![];
-
                         // => f.debug_tuple(name)
                         let target = make::expr_path(make::ext::ident_path("f"));
                         let method = make::name_ref("debug_tuple");
                         let struct_name = format!("\"{}\"", name);
                         let args = make::arg_list(Some(make::expr_literal(&struct_name).into()));
                         let mut expr = make::expr_method_call(target, method, args);
 
+                        let mut pats = vec![];
                         for (i, _) in list.fields().enumerate() {
                             let name = format!("arg{}", i);
 
@@ -224,7 +221,7 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                     }
                     None => {
                         let fmt_string = make::expr_literal(&(format!("\"{}\"", name))).into();
-                        let args = make::arg_list(vec![target, fmt_string]);
+                        let args = make::arg_list([target, fmt_string]);
                         let macro_name = make::expr_path(make::ext::ident_path("write"));
                         let macro_call = make::expr_macro_call(macro_name, args);
 
@@ -267,7 +264,7 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                         let f_path = make::expr_path(make::ext::ident_path("self"));
                         let f_path = make::expr_ref(f_path, false);
                         let f_path = make::expr_field(f_path, &format!("{}", name)).into();
-                        let args = make::arg_list(vec![f_name, f_path]);
+                        let args = make::arg_list([f_name, f_path]);
                         expr = make::expr_method_call(expr, make::name_ref("field"), args);
                     }
                     expr