Do not process inner aliased types when generating ABI type string.

Author: tritao

sway-core/src/abi_generation/abi_str.rs

@@ -35,10 +35,7 @@ impl TypeId {
                 | (TypeInfo::Custom { .. }, TypeInfo::Enum { .. }) => type_engine
                     .get(resolved_type_id)
                     .abi_str(handler, ctx, engines, true),
-                (_, TypeInfo::Alias { ty, .. }) => {
-                    ty.type_id()
-                        .get_abi_type_str(handler, ctx, engines, ty.type_id())
-                }
+                (_, TypeInfo::Alias { .. }) => Ok(self_abi_str),
                 (TypeInfo::Tuple(fields), TypeInfo::Tuple(resolved_fields)) => {
                     assert_eq!(fields.len(), resolved_fields.len());
                     let field_strs = resolved_fields
@@ -203,7 +200,10 @@ impl TypeInfo {
                 "__slice {}",
                 ty.abi_str(handler, ctx, engines, false)?
             )),
-            Alias { ty, .. } => Ok(ty.abi_str(handler, ctx, engines, false)?),
+            Alias { .. } => {
+                // Aliases are handled specially when processing the ABI, so we should never get here.
+                unreachable!()
+            }
             TraitType {
                 name,
                 implemented_in: _,