[BOOST-5221] feat(sdk): update tuple support helpers to add terminators

.changeset/breezy-jokes-judge.md

@@ -0,0 +1,5 @@
+---
+"@boostxyz/sdk": patch
+---
+
+[BOOST-5221] feat(sdk): update tuple support helpers to add terminators

packages/sdk/src/Actions/EventAction.test.ts

@@ -1241,6 +1241,15 @@ describe("Tuple & bitpacked fieldIndex support", () => {
       expect(result).toEqual(resultIndexes);
     });
 
+    test("packs 3 indexes with the automatic addition of a terminator and unpacks them correctly", () => {
+      const indexes = [0, 3, 5]; // sample indexes
+      const packed = packFieldIndexes(indexes);
+      const result = unpackFieldIndexes(packed);
+      const resultIndexes = [0, 3, 5]; // should terminate on it's own even if a terminator isn't passed in
+
+      expect(result).toEqual(resultIndexes);
+    });
+
     test("throws if more than five indexes are provided", () => {
       expect(() => packFieldIndexes([1, 2, 3, 4, 5, 6])).toThrowError(
         "Can only pack up to 5 indexes.",

packages/sdk/src/Actions/EventAction.ts

@@ -1611,6 +1611,9 @@ export function packFieldIndexes(indexes: number[]): number {
     }
     packed |= (index & MAX_FIELD_INDEX) << (i * 6); // Each index occupies 6 bits
   });
+  if (indexes.length < 5) {
+    packed |= MAX_FIELD_INDEX << (indexes.length * 6); // Terminator
+  }
 
   return packed;
 }