Add justification to non-static lifetime diagnostic

dtolnay · Dec 27, 2020 · d31d96b · d31d96b
1 parent 464a409
commit d31d96b
Show file tree

Hide file tree

Showing 2 changed files with 2 additions and 2 deletions.
diff --git a/impl/src/valid.rs b/impl/src/valid.rs
@@ -191,7 +191,7 @@ fn check_field_attrs(fields: &[Field]) -> Result<()> {
         if contains_non_static_lifetime(source_field) {
             return Err(Error::new_spanned(
                 &source_field.original.ty,
-                "non-static lifetimes are not allowed in the source of an error",
+                "non-static lifetimes are not allowed in the source of an error, because std::error::Error requires the source is dyn Error + 'static",
             ));
         }
     }

diff --git a/tests/ui/lifetime.stderr b/tests/ui/lifetime.stderr
@@ -1,4 +1,4 @@
-error: non-static lifetimes are not allowed in the source of an error
+error: non-static lifetimes are not allowed in the source of an error, because std::error::Error requires the source is dyn Error + 'static
  --> $DIR/lifetime.rs:5:26
   |
 5 | struct Error<'a>(#[from] Inner<'a>);