Added error message and test case for using undeclared implementation parameters on functions within trait implementations

Author: IsaacShelton

src/resolve/impl_head.rs

@@ -138,8 +138,14 @@ fn ensure_satisfies_trait_func(
     trait_func: &TraitFunc,
     impl_func: &Func,
 ) -> Result<(), ResolveError> {
-    let mut for_alls = ForAlls::default();
+    if !impl_func.impl_params.params.is_empty() {
+        return Err(ResolveError::other(
+            "Implementation parameter is not allowed by trait definition",
+            impl_func.source,
+        ));
+    }
 
+    let mut for_alls = ForAlls::default();
     let mut mappings = HashMap::new();
     for sub in expected.values() {
         collect_constraints_into(&mut mappings, sub);

tests/error/using_trait_on_impl_func/main.adept

@@ -0,0 +1,18 @@
+
+pragma => adept(c"3.0")
+
+trait Speak<$T> {
+    func speak(self $T) void
+}
+
+trait Act {
+    func act() void
+}
+
+impl Act myExampleImpl {
+    #[using Speak<int>]
+    func act() {}
+}
+
+func main {}
+

tests/error/using_trait_on_trait_func/main.adept

@@ -1,16 +1,14 @@
 
 pragma => adept(c"3.0")
 
-trait Example<$T> {
-    #[using Speak<$T>]
-    func invalidFunction(self $T) void
-}
-
 trait Speak<$T> {
     func speak(self $T) void
 }
 
-func main {
-    
+trait InvalidTrait<$T> {
+    #[using Speak<$T>]
+    func invalidFunction(self $T) void
 }
 
+func main {}
+