default_trait_access skips <F as Default>::default()

This includes the type name, so is clear, and may be necessary.

There doesn't seem to be an obviously cleaner way to pull out the
literal text of the named type here.

Fixes #2879

Author: illicitonion

clippy_lints/src/default_trait_access.rs

@@ -48,6 +48,13 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for DefaultTraitAccess {
             then {
                 match qpath {
                     QPath::Resolved(..) => {
+                        if let ExprKind::Call(ref method, ref _args) = expr.node {
+                            if format!("{:?}", method).contains(" as Default>") {
+                                return
+                            }
+                        }
+
+
                         // TODO: Work out a way to put "whatever the imported way of referencing
                         // this type in this file" rather than a fully-qualified type.
                         let expr_ty = cx.tables.expr_ty(expr);

tests/ui/default_trait_access.rs

@@ -41,8 +41,10 @@ fn main() {
 
     let s18 = TupleStructDerivedDefault::default();
 
+    let s19 = <DerivedDefault as Default>::default();
+
     println!(
-        "[{}] [{}] [{}] [{}] [{}] [{}] [{}] [{}] [{}] [{:?}] [{:?}] [{:?}] [{:?}] [{:?}] [{:?}] [{:?}] [{:?}] [{:?}]",
+        "[{}] [{}] [{}] [{}] [{}] [{}] [{}] [{}] [{}] [{:?}] [{:?}] [{:?}] [{:?}] [{:?}] [{:?}] [{:?}] [{:?}] [{:?}], [{:?}]",
         s1,
         s2,
         s3,
@@ -61,6 +63,7 @@ fn main() {
         s16,
         s17,
         s18,
+        s19,
     );
 }