Simplify using utils

Author: Henri Lunnikivi

clippy_lints/src/field_reassign_with_default.rs

@@ -1,4 +1,4 @@
-use crate::utils::{snippet, span_lint_and_note};
+use crate::utils::{snippet, span_lint_and_note, match_path_ast, paths};
 use if_chain::if_chain;
 use rustc_ast::ast::{BindingMode, Block, ExprKind, Mutability, PatKind, StmtKind};
 use rustc_lint::{EarlyContext, EarlyLintPass};
@@ -38,14 +38,10 @@ declare_clippy_lint! {
 
 declare_lint_pass!(FieldReassignWithDefault => [FIELD_REASSIGN_WITH_DEFAULT]);
 
-/// The token for the Default -trait.
-const DEFAULT_TRAIT_TOKEN: &str = "Default";
-const DEFAULT_FUNC_TOKEN: &str = "default";
-
 impl EarlyLintPass for FieldReassignWithDefault {
     fn check_block(&mut self, cx: &EarlyContext<'_>, block: &Block) {
         // store statement index and name of binding for all statements like
-        // `let mut <binding> = Default::default();`
+        // `let mut binding = Default::default();`
         let binding_statements_using_default: Vec<(usize, Symbol)> = block
             .stmts
             .iter()
@@ -60,10 +56,8 @@ impl EarlyLintPass for FieldReassignWithDefault {
                     if let Some(ref expr) = local.init;
                     if let ExprKind::Call(ref fn_expr, _) = &expr.kind;
                     if let ExprKind::Path( _, path ) = &fn_expr.kind;
-                    if path.segments.len() >= 2;
                     // right hand side of assignment is `Default::default`
-                    if path.segments[path.segments.len()-2].ident.to_string() == DEFAULT_TRAIT_TOKEN;
-                    if path.segments.last().unwrap().ident.to_string() == DEFAULT_FUNC_TOKEN;
+                    if match_path_ast(&path, &paths::DEFAULT_TRAIT_METHOD);
                     then {
                         Some((idx, binding.name))
                     }