2 files changed, 15 insertions, 0 deletions
diff --git a/ui-tests/src/bin/unconvertible_type.rs b/ui-tests/src/bin/unconvertible_type.rs
new file mode 100644
index 0000000..6fd68d4
--- /dev/null
+++ b/ui-tests/src/bin/unconvertible_type.rs
@@ -0,0 +1,10 @@
+type Foo<T> = Option<T>;
+
+#[dynamize::dynamize]
+trait Trait {
+    type A: std::error::Error;
+
+    fn a(&self) -> Option<Foo<Self::A>>;
+}
+
+fn main() {}
diff --git a/ui-tests/src/bin/unconvertible_type.stderr b/ui-tests/src/bin/unconvertible_type.stderr
new file mode 100644
index 0000000..462b939
--- /dev/null
+++ b/ui-tests/src/bin/unconvertible_type.stderr
@@ -0,0 +1,5 @@
+error: dynamize does not know how to convert this type
+ --> src/bin/unconvertible_type.rs:7:31
+  |
+7 |     fn a(&self) -> Option<Foo<Self::A>>;
+  |                               ^^^^