test that same-named generics need same bounds

1 files changed, 38 insertions, 1 deletions

diff --git a/tests/doctests.md b/tests/doctests.md
index ef557fe..3318dba 100644
--- a/tests/doctests.md
+++ b/tests/doctests.md
@@ -1,4 +1,4 @@
-Tests that the object-safety assertion via `impl dyn` is working:
+## If the dynamized trait isn't object safe you get a compile error
 
 ```rust compile_fail
 trait ObjectUnsafe: Sized {}
@@ -17,3 +17,40 @@ trait Trait {
     fn f(&self) -> Self::A;
 }
 ```
+
+## Same-named method generics must have same trait bounds
+
+Works:
+
+```rust
+#[dynamize::dynamize]
+trait Trait {
+    type A: std::error::Error;
+
+    fn a<A: std::fmt::Display>(&self, a: A) -> Self::A;
+    fn b<A: std::fmt::Display>(&self, a: A) -> Self::A;
+}
+```
+
+```rust
+#[dynamize::dynamize]
+trait Trait {
+    type A: std::error::Error;
+
+    fn a<A>(&self, a: A) -> Self::A;
+    fn b<B: std::fmt::Display>(&self, a: B) -> Self::A;
+}
+```
+
+
+Fails:
+
+```rust compile_fail
+#[dynamize::dynamize]
+trait Trait {
+    type A: std::error::Error;
+
+    fn a<A>(&self, a: A) -> Self::A;
+    fn b<A: std::fmt::Display>(&self, a: A) -> Self::A;
+}
+```