Optional vbar for ReasonLIGO sumtypes

src/passes/1-parser/reasonligo/Parser.mly

@@ -226,7 +226,7 @@ core_type:
    in TApp {region; value = constr,arg} }
 
 sum_type:
-  "|" nsepseq(variant,"|") {
+  ioption("|") nsepseq(variant,"|") {
     Scoping.check_variants (Utils.nsepseq_to_list $2);
     let region = nsepseq_to_region (fun x -> x.region) $2
     in TSum {region; value=$2} }

src/test/contracts/match_bis.religo

@@ -3,7 +3,7 @@ type storage = int;
 /* variant defining pseudo multi-entrypoint actions */
 
 type action =
-  | Increment(int)
+    Increment(int)
   | Decrement(int);
 
 let add = ((a: int), (b: int)) => a + b;