From ba9f7f1e755ea838bf5fa457937e4ed6efe8c8bb Mon Sep 17 00:00:00 2001
From: Alasdair <alasdair.armstrong@cl.cam.ac.uk>
Date: Mon, 6 May 2024 18:37:04 +0100
Subject: [PATCH] Make sure P_vector_subrange ids are returned by
 check_pattern_duplicates

---
 src/lib/type_check.ml                            |  2 +-
 src/lib/type_error.mli                           |  1 +
 test/typecheck/pass/vector_subrange_mapping.sail | 11 +++++++++++
 3 files changed, 13 insertions(+), 1 deletion(-)
 create mode 100644 test/typecheck/pass/vector_subrange_mapping.sail

diff --git a/src/lib/type_check.ml b/src/lib/type_check.ml
index 913675a00..6f2fbd696 100644
--- a/src/lib/type_check.ml
+++ b/src/lib/type_check.ml
@@ -1600,7 +1600,7 @@ let check_pattern_duplicates env pat =
                      Err_other "Regular binding is here"
                    )
                 )
-          | None -> ()
+          | None -> ids := Bindings.add subrange_id (Pattern_singleton l) !ids
         )
         !subrange_ids;
       !ids
diff --git a/src/lib/type_error.mli b/src/lib/type_error.mli
index e348892c1..1aed09883 100644
--- a/src/lib/type_error.mli
+++ b/src/lib/type_error.mli
@@ -119,6 +119,7 @@ val analyze_unresolved_quant :
 
 val string_of_type_error : type_error -> string * string option
 
+(** Convert a type error into a general purpose error from the Reporting file *)
 val to_reporting_exn : Parse_ast.l -> type_error -> exn
 
 val check_defs : Type_check.Env.t -> uannot Ast.def list -> Type_check.tannot Ast.def list * Type_check.Env.t
diff --git a/test/typecheck/pass/vector_subrange_mapping.sail b/test/typecheck/pass/vector_subrange_mapping.sail
new file mode 100644
index 000000000..06d454d96
--- /dev/null
+++ b/test/typecheck/pass/vector_subrange_mapping.sail
@@ -0,0 +1,11 @@
+default Order dec
+
+$include <prelude.sail>
+
+union Foo = {
+  Bar : bits(32)
+}
+
+mapping baz : Foo <-> bits(32) = {
+  Bar(imm) <-> imm[31 .. 16] @ imm[15 .. 0]
+}