[`derivable_impls`]: don't lint if expr unsize-coerces

2 files changed, 42 insertions, 0 deletions

diff --git a/tests/ui/derivable_impls.fixed b/tests/ui/derivable_impls.fixed
index aa0efb85c29..a10f3d01070 100644
--- a/tests/ui/derivable_impls.fixed
+++ b/tests/ui/derivable_impls.fixed
@@ -268,4 +268,25 @@ impl Default for OtherGenericType {
     }
 }
 
+mod issue10158 {
+    pub trait T {}
+
+    #[derive(Default)]
+    pub struct S {}
+    impl T for S {}
+
+    pub struct Outer {
+        pub inner: Box<dyn T>,
+    }
+
+    impl Default for Outer {
+        fn default() -> Self {
+            Outer {
+                // Box::<S>::default() adjusts to Box<dyn T>
+                inner: Box::<S>::default(),
+            }
+        }
+    }
+}
+
 fn main() {}
diff --git a/tests/ui/derivable_impls.rs b/tests/ui/derivable_impls.rs
index 8dc999ad586..18cef1c5be8 100644
--- a/tests/ui/derivable_impls.rs
+++ b/tests/ui/derivable_impls.rs
@@ -304,4 +304,25 @@ impl Default for OtherGenericType {
     }
 }
 
+mod issue10158 {
+    pub trait T {}
+
+    #[derive(Default)]
+    pub struct S {}
+    impl T for S {}
+
+    pub struct Outer {
+        pub inner: Box<dyn T>,
+    }
+
+    impl Default for Outer {
+        fn default() -> Self {
+            Outer {
+                // Box::<S>::default() adjusts to Box<dyn T>
+                inner: Box::<S>::default(),
+            }
+        }
+    }
+}
+
 fn main() {}