Merge pull request #9 from torusresearch/fix_denormalize_share

fix: conversion for denormalizeShare

Author: metalurgical

Sources/tss-client-swift/Helpers.swift

@@ -219,13 +219,13 @@ public class TSSHelpers {
     ///   - userTssIndex: The current tss index for the user
     ///   - userTssShare: The current tss share for the user
     ///
-    /// - Returns: `BigInt`
+    /// - Returns: `String`
     ///
     /// - Throws: `TSSClientError` 
-    public static func denormalizeShare(participatingServerDKGIndexes: [BigInt], userTssIndex: BigInt, userTssShare: BigInt) throws -> BigInt {
+    public static func denormalizeShare(participatingServerDKGIndexes: [BigInt], userTssIndex: BigInt, userTssShare: BigInt) throws -> String {
         let coeff = try getDKLSCoefficient(isUser: true, participatingServerIndexes: participatingServerDKGIndexes, userTssIndex: userTssIndex, serverIndex: nil)
         let denormalizeShare = (coeff  * userTssShare ).modulus(TSSClient.modulusValueSigned)
-        return denormalizeShare
+        return denormalizeShare.magnitude.serialize().toHexString()
     }
 
     /// Calculates the public key that will be used for TSS signing.

Tests/tss-client-swiftTests/helperTests.swift

@@ -64,8 +64,8 @@ final class helpersTests: XCTestCase {
         let denormalize2 = try TSSHelpers.denormalizeShare(participatingServerDKGIndexes: [BigInt(1), BigInt(2), BigInt(3) ], userTssIndex: BigInt(2), userTssShare: BigInt(sign: .plus, magnitude: share))
         let denormalize3 = try TSSHelpers.denormalizeShare(participatingServerDKGIndexes: [BigInt(1), BigInt(2), BigInt(3) ], userTssIndex: BigInt(3), userTssShare: BigInt(sign: .plus, magnitude: share))
 
-        XCTAssert(denormalize2 == BigInt("18db3574e4217154769ad9cd88900e7f1c198aa60a1379f3869ba8a7699e6b53", radix: 16))
-        XCTAssert(denormalize3 == BigInt("008c6d9aba7210b8aa3b4d6ce6c448073eeb6433c65cae0d17a337039a1cea564a", radix: 16))
+        XCTAssert(denormalize2 == "18db3574e4217154769ad9cd88900e7f1c198aa60a1379f3869ba8a7699e6b53")
+        XCTAssert(denormalize3 == "8c6d9aba7210b8aa3b4d6ce6c448073eeb6433c65cae0d17a337039a1cea564a")
     }
 
     func testFinalGetTSSPubkey() throws{