Correctly handle specialising polymorphic types in nested unions

Ensure that this works even when the union types are dependent in the wrong order, before topologically sorting definitions. We do this by calling fix_variant_ctyps on all cdefs by passing a list of
prior cdefs to specialize_variants.

2 files changed, 19 insertions, 0 deletions

diff --git a/test/c/option_nest.expect b/test/c/option_nest.expect
new file mode 100644
index 00000000..9daeafb9
--- /dev/null
+++ b/test/c/option_nest.expect
@@ -0,0 +1 @@
+test
diff --git a/test/c/option_nest.sail b/test/c/option_nest.sail
new file mode 100644
index 00000000..995bf074
--- /dev/null
+++ b/test/c/option_nest.sail
@@ -0,0 +1,18 @@
+
+union test ('a : Type) = {
+  Just : 'a,
+  Nothing : unit 
+}
+
+union option ('a : Type) = {
+  None : unit,
+  Some : 'a
+}
+
+val "print_endline" : string -> unit
+
+function main() : unit -> unit = {
+  let _ : test(option(int)) = Just(None());
+  let Just(Some(x)) = Just(Some("test"));
+  print_endline(x)
+}
\ No newline at end of file