#68 Fix code review issues

Author: martti007

src/main/java/org/unicitylabs/sdk/payment/SplitMintJustification.java

@@ -5,9 +5,9 @@
 import org.unicitylabs.sdk.serializer.cbor.CborSerializer;
 import org.unicitylabs.sdk.transaction.Token;
 
+import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
-import java.util.Set;
 import java.util.stream.Collectors;
 
 /**
@@ -54,14 +54,18 @@ public List<SplitAssetProof> getProofs() {
    *
    * @return split mint justification
    */
-  public static SplitMintJustification create(Token token, Set<SplitAssetProof> proofs) {
+  public static SplitMintJustification create(Token token, List<SplitAssetProof> proofs) {
     Objects.requireNonNull(token, "token cannot be null");
     Objects.requireNonNull(proofs, "proofs cannot be null");
 
     if (proofs.isEmpty()) {
       throw new IllegalArgumentException("proofs cannot be empty");
     }
 
+    if (new HashSet<>(proofs).size() != proofs.size()) {
+      throw new IllegalArgumentException("proofs contain duplicate asset ids");
+    }
+
     return new SplitMintJustification(token, List.copyOf(proofs));
   }
 
@@ -80,7 +84,9 @@ public static SplitMintJustification fromCbor(byte[] bytes) {
     List<byte[]> data = CborDeserializer.decodeArray(tag.getData(), 2);
     return SplitMintJustification.create(
             Token.fromCbor(data.get(0)),
-            CborDeserializer.decodeArray(data.get(1)).stream().map(SplitAssetProof::fromCbor).collect(Collectors.toSet())
+            CborDeserializer.decodeArray(data.get(1)).stream()
+                    .map(SplitAssetProof::fromCbor)
+                    .collect(Collectors.toList())
     );
   }
 

src/main/java/org/unicitylabs/sdk/payment/TokenSplit.java

@@ -144,7 +144,7 @@ public static SplitResult split(
     for (Entry<TokenId, SplitTokenRequest> entry : requestsByTokenId.entrySet()) {
       SplitTokenRequest request = entry.getValue();
       BigInteger tokenIdPath = entry.getKey().toBitString().toBigInteger();
-      Set<Asset> requestAssets = new HashSet<>(request.getAssets());
+      Set<Asset> requestAssets = request.getAssets();
       List<SplitAssetProof> proofs = requestAssets.stream()
               .map(asset -> SplitAssetProof.create(
                       asset.getId(),

src/test/java/org/unicitylabs/sdk/functional/payment/SplitBuilderTest.java

@@ -24,7 +24,6 @@
 
 import java.math.BigInteger;
 import java.nio.charset.StandardCharsets;
-import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Set;
 
@@ -81,7 +80,7 @@ public void buildAndVerifySplitToken() throws Exception {
     SplitToken splitResult = split.getTokens().get(0);
     SplitMintJustification justification = SplitMintJustification.create(
             burnToken,
-            new LinkedHashSet<>(splitResult.getProofs())
+            splitResult.getProofs()
     );
 
     Token splitToken = TokenUtils.mintToken(

src/test/java/org/unicitylabs/sdk/functional/payment/SplitMintJustificationVerifierTest.java

@@ -40,7 +40,6 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Iterator;
-import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Set;
 import java.util.stream.Collectors;
@@ -111,7 +110,7 @@ public void setupFixture() throws Exception {
     SplitToken splitResult = split.getTokens().get(0);
     this.splitJustification = SplitMintJustification.create(
             burnToken,
-            new LinkedHashSet<>(splitResult.getProofs())
+            splitResult.getProofs()
     );
 
     this.splitToken = TokenUtils.mintToken(
@@ -218,7 +217,7 @@ public void verifyFailsWhenAggregationPathVerificationFails() throws Exception {
     );
 
     SplitMintJustification mutated = SplitMintJustification.create(
-            this.splitJustification.getToken(), new LinkedHashSet<>(proofs));
+            this.splitJustification.getToken(), proofs);
 
     VerificationResult<VerificationStatus> result = verifyWith(mutated.toCbor(), originalDataBytes());
     assertFailWithMessage(result,
@@ -240,7 +239,7 @@ public void verifyFailsWhenAssetTreePathVerificationFails() throws Exception {
     proofs.set(0, mutatedProof);
 
     SplitMintJustification mutated = SplitMintJustification.create(
-            this.splitJustification.getToken(), new LinkedHashSet<>(proofs));
+            this.splitJustification.getToken(), proofs);
 
     VerificationResult<VerificationStatus> result = verifyWith(mutated.toCbor(), originalDataBytes());
     assertFailWithMessage(result,
@@ -267,7 +266,7 @@ public void verifyFailsWhenProofsUseDifferentAssetTrees() throws Exception {
     ));
 
     SplitMintJustification mutated = SplitMintJustification.create(
-            this.splitJustification.getToken(), new LinkedHashSet<>(proofs));
+            this.splitJustification.getToken(), proofs);
 
     VerificationResult<VerificationStatus> result = verifyWith(mutated.toCbor(), originalDataBytes());
     assertFailWithMessage(result, "Current proof is not derived from the same asset tree as other proofs.");
@@ -295,7 +294,7 @@ public void verifyFailsWhenAssetTreeRootDoesNotMatchAggregationLeaf() throws Exc
     proofs.set(0, mutatedProof);
 
     SplitMintJustification mutated = SplitMintJustification.create(
-            this.splitJustification.getToken(), new LinkedHashSet<>(proofs));
+            this.splitJustification.getToken(), proofs);
 
     VerificationResult<VerificationStatus> result = verifyWith(mutated.toCbor(), originalDataBytes());
     assertFailWithMessage(result, "Asset tree root does not match aggregation path leaf.");
@@ -310,7 +309,7 @@ public void verifyFailsWhenProofAssetIdIsMissingFromAssetData() {
             .collect(Collectors.toSet());
 
     SplitMintJustification mutated = SplitMintJustification.create(
-            this.splitJustification.getToken(), new LinkedHashSet<>(proofs));
+            this.splitJustification.getToken(), proofs);
     byte[] data = new TestPaymentData(assets).encode();
 
     VerificationResult<VerificationStatus> result = verifyWith(mutated.toCbor(), data);
@@ -360,7 +359,7 @@ public void verifyFailsWhenAggregationRootDoesNotMatchBurnPredicate() throws Exc
     }
 
     SplitMintJustification mutated = SplitMintJustification.create(
-            this.splitJustification.getToken(), new LinkedHashSet<>(mutatedProofs));
+            this.splitJustification.getToken(), mutatedProofs);
 
     VerificationResult<VerificationStatus> result = verifyWith(mutated.toCbor(), originalDataBytes());
     assertFailWithMessage(result, "Aggregation path root does not match burn predicate.");