Add Transaction.getUnsignedSerialized (#135)

xclud · Dec 23, 2023 · 3e25bcb · 3e25bcb
1 parent d9fe445
commit 3e25bcb
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Showing 2 changed files with 29 additions and 20 deletions.
diff --git a/lib/src/core/transaction.dart b/lib/src/core/transaction.dart
@@ -95,4 +95,30 @@ class Transaction {
   }
 
   bool get isEIP1559 => maxFeePerGas != null || maxPriorityFeePerGas != null;
+
+  /// The transaction pre-image.
+  ///
+  /// The hash of this is the digest which needs to be signed to
+  /// authorize this transaction.
+  Uint8List getUnsignedSerialized({
+    int? chainId = 1,
+  }) {
+    if (isEIP1559 && chainId != null) {
+      final encodedTx = LengthTrackingByteSink();
+      encodedTx.addByte(0x02);
+      encodedTx.add(
+        rlp.encode(_encodeEIP1559ToRlp(this, null, BigInt.from(chainId))),
+      );
+
+      encodedTx.close();
+
+      return encodedTx.asBytes();
+    }
+
+    final innerSignature = chainId == null
+        ? null
+        : MsgSignature(BigInt.zero, BigInt.zero, chainId);
+
+    return uint8ListFromList(rlp.encode(_encodeToRlp(this, innerSignature)));
+  }
 }
diff --git a/lib/src/core/transaction_signer.dart b/lib/src/core/transaction_signer.dart
@@ -105,33 +105,16 @@ Uint8List signTransactionRaw(
   Credentials c, {
   int? chainId = 1,
 }) {
-  if (transaction.isEIP1559 && chainId != null) {
-    final encodedTx = LengthTrackingByteSink();
-    encodedTx.addByte(0x02);
-    encodedTx.add(
-      rlp.encode(_encodeEIP1559ToRlp(transaction, null, BigInt.from(chainId))),
-    );
-
-    encodedTx.close();
-    final signature = c.signToEcSignature(
-      encodedTx.asBytes(),
-      chainId: chainId,
-      isEIP1559: transaction.isEIP1559,
-    );
+  final encoded = transaction.getUnsignedSerialized(chainId: chainId);
+  final signature = c.signToEcSignature(encoded, chainId: chainId, isEIP1559: transaction.isEIP1559);
 
+  if (transaction.isEIP1559 && chainId != null) {
     return uint8ListFromList(
       rlp.encode(
         _encodeEIP1559ToRlp(transaction, signature, BigInt.from(chainId)),
       ),
     );
   }
-  final innerSignature =
-      chainId == null ? null : MsgSignature(BigInt.zero, BigInt.zero, chainId);
-
-  final encoded =
-      uint8ListFromList(rlp.encode(_encodeToRlp(transaction, innerSignature)));
-  final signature = c.signToEcSignature(encoded, chainId: chainId);
-
   return uint8ListFromList(rlp.encode(_encodeToRlp(transaction, signature)));
 }