Handle functions for the builtin Sized trait

Author: marmeladema

chalk-solve/src/clauses/builtin_traits/sized.rs

@@ -77,6 +77,7 @@ pub fn add_sized_program_clauses<I: Interner>(
             }
             _ => return,
         },
+        TyData::Function(_) => builder.push_fact(trait_ref.clone()),
         // TODO(areredify)
         // when #368 lands, extend this to handle everything accordingly
         _ => return,

tests/test/functions.rs

@@ -0,0 +1,25 @@
+use super::*;
+
+#[test]
+fn functions_are_sized() {
+    test! {
+        program {
+            #[lang(sized)]
+            trait Sized { }
+
+            trait Copy {}
+        }
+
+        goal {
+            fn(()): Sized
+        } yields {
+            "Unique; substitution [], lifetime constraints []"
+        }
+
+        goal {
+            fn(dyn Copy): Sized
+        } yields {
+            "Unique; substitution [], lifetime constraints []"
+        }
+    }
+}

tests/test/mod.rs

@@ -309,6 +309,7 @@ mod coherence_goals;
 mod coinduction;
 mod cycle;
 mod existential_types;
+mod functions;
 mod implied_bounds;
 mod impls;
 mod misc;