Refactor

clippy_lints/src/methods/unwrap_or_else_default.rs

@@ -2,8 +2,8 @@
 
 use super::UNWRAP_OR_ELSE_DEFAULT;
 use clippy_utils::{
-    diagnostics::span_lint_and_sugg, is_default_equivalent_ctor, is_diag_trait_item, is_trait_item,
+    diagnostics::span_lint_and_sugg, is_default_equivalent_call, is_trait_item, source::snippet_with_applicability,
-    source::snippet_with_applicability, ty::is_type_diagnostic_item,
+    ty::is_type_diagnostic_item,
 };
 use rustc_errors::Applicability;
 use rustc_hir as hir;
@@ -23,21 +23,9 @@ pub(super) fn check<'tcx>(
     let is_option = is_type_diagnostic_item(cx, recv_ty, sym::Option);
     let is_result = is_type_diagnostic_item(cx, recv_ty, sym::Result);
 
-    let is_default_eq = match &u_arg.kind {
-        hir::ExprKind::Path(qpath) => {
-            if let Some(repl_def_id) = cx.qpath_res(qpath, u_arg.hir_id).opt_def_id() {
-                is_diag_trait_item(cx, repl_def_id, sym::Default)
-                    || is_default_equivalent_ctor(cx, repl_def_id, qpath)
-            } else {
-                false
-            }
-        },
-        _ => false,
-    };
-
     if_chain! {
         if is_option || is_result;
-        if is_trait_item(cx, u_arg, sym::Default) || is_default_eq;
+        if is_trait_item(cx, u_arg, sym::Default) || is_default_equivalent_call(cx, u_arg);
         then {
             let mut applicability = Applicability::MachineApplicable;
 

clippy_utils/src/lib.rs

@@ -637,7 +637,7 @@ pub fn can_mut_borrow_both(cx: &LateContext<'_>, e1: &Expr<'_>, e2: &Expr<'_>) -
 
 /// Returns true if the `def_id` associated with the `path` is recognized as a "default-equivalent"
 /// constructor from the std library
-pub fn is_default_equivalent_ctor(cx: &LateContext<'_>, def_id: DefId, path: &QPath<'_>) -> bool {
+fn is_default_equivalent_ctor(cx: &LateContext<'_>, def_id: DefId, path: &QPath<'_>) -> bool {
     let std_types_symbols = &[
         sym::String,
         sym::Vec,
@@ -664,6 +664,22 @@ pub fn is_default_equivalent_ctor(cx: &LateContext<'_>, def_id: DefId, path: &QP
     false
 }
 
+/// Return true if the expr is equal to `Default::default` when evaluated.
+pub fn is_default_equivalent_call(cx: &LateContext<'_>, repl_func: &Expr<'_>) -> bool {
+    if_chain! {
+        if let hir::ExprKind::Path(ref repl_func_qpath) = repl_func.kind;
+        if let Some(repl_def_id) = cx.qpath_res(repl_func_qpath, repl_func.hir_id).opt_def_id();
+        if is_diag_trait_item(cx, repl_def_id, sym::Default)
+            || is_default_equivalent_ctor(cx, repl_def_id, repl_func_qpath);
+        then {
+            true
+        }
+        else {
+            false
+        }
+    }
+}
+
 /// Returns true if the expr is equal to `Default::default()` of it's type when evaluated.
 /// It doesn't cover all cases, for example indirect function calls (some of std
 /// functions are supported) but it is the best we have.
@@ -686,18 +702,7 @@ pub fn is_default_equivalent(cx: &LateContext<'_>, e: &Expr<'_>) -> bool {
                 false
             }
         },
-        ExprKind::Call(repl_func, _) => if_chain! {
+        ExprKind::Call(repl_func, _) => is_default_equivalent_call(cx, repl_func),
-            if let ExprKind::Path(ref repl_func_qpath) = repl_func.kind;
-            if let Some(repl_def_id) = cx.qpath_res(repl_func_qpath, repl_func.hir_id).opt_def_id();
-            if is_diag_trait_item(cx, repl_def_id, sym::Default)
-                || is_default_equivalent_ctor(cx, repl_def_id, repl_func_qpath);
-            then {
-                true
-            }
-            else {
-                false
-            }
-        },
         ExprKind::Path(qpath) => is_lang_ctor(cx, qpath, OptionNone),
         ExprKind::AddrOf(rustc_hir::BorrowKind::Ref, _, expr) => matches!(expr.kind, ExprKind::Array([])),
         _ => false,