From c7ab80f743b3e2d34bb702be787507418cc794a8 Mon Sep 17 00:00:00 2001
From: Patrick Walton <pcwalton@mimiga.net>
Date: Thu, 14 Oct 2010 15:02:35 -0700
Subject: [PATCH] Typecheck tags in "alt" patterns

---
 src/boot/me/type.ml                      |  2 ++
 src/test/compile-fail/alt-tag-nullary.rs | 12 ++++++++++++
 src/test/compile-fail/alt-tag-unary.rs   | 12 ++++++++++++
 3 files changed, 26 insertions(+)
 create mode 100644 src/test/compile-fail/alt-tag-nullary.rs
 create mode 100644 src/test/compile-fail/alt-tag-unary.rs

diff --git a/src/boot/me/type.ml b/src/boot/me/type.ml
index 66dd240efa9..648618e70ba 100644
--- a/src/boot/me/type.ml
+++ b/src/boot/me/type.ml
@@ -903,8 +903,10 @@ let check_stmt (cx:Semant.ctxt) : (fn_ctx -> Ast.stmt -> unit) =
           let arg_tys =
             match constr_ty with
                 Ast.TY_fn (ty_sig, _) ->
+                  demand expected (get_slot_ty ty_sig.Ast.sig_output_slot);
                   Array.map get_slot_ty ty_sig.Ast.sig_input_slots
               | Ast.TY_tag _ ->
+                  demand expected constr_ty;
                   [||]
               | _ -> type_error "constructor function" constr_ty
           in
diff --git a/src/test/compile-fail/alt-tag-nullary.rs b/src/test/compile-fail/alt-tag-nullary.rs
new file mode 100644
index 00000000000..f55f67e9e18
--- /dev/null
+++ b/src/test/compile-fail/alt-tag-nullary.rs
@@ -0,0 +1,12 @@
+// error-pattern: mismatched types
+
+tag a { A; }
+tag b { B; }
+
+fn main() {
+    let a x = A;
+    alt (x) {
+        case (B) {}
+    }
+}
+
diff --git a/src/test/compile-fail/alt-tag-unary.rs b/src/test/compile-fail/alt-tag-unary.rs
new file mode 100644
index 00000000000..f2004896a2d
--- /dev/null
+++ b/src/test/compile-fail/alt-tag-unary.rs
@@ -0,0 +1,12 @@
+// error-pattern: mismatched types
+
+tag a { A(int); }
+tag b { B(int); }
+
+fn main() {
+    let a x = A(0);
+    alt (x) {
+        case (B(?y)) {}
+    }
+}
+