Merge pull request #13 from nvergez/main

Do not remove functionName & functionArgs if no args but receiver is smart contract
multiversx · Sep 11, 2024 · c12bd3e · c12bd3e
2 parents 4e36ecb + f9ff996
commit c12bd3e
Show file tree

Hide file tree

Showing 2 changed files with 31 additions and 2 deletions.
diff --git a/src/transaction.decoder.ts b/src/transaction.decoder.ts
@@ -1,5 +1,7 @@
 import { bech32 } from "bech32";
 
+const SMART_CONTRACT_HEX_PUBKEY_PREFIX = "0".repeat(16);
+
 export class TransactionDecoder {
   getTransactionMetadata(transaction: TransactionToDecode): TransactionMetadata {
     const metadata = this.getNormalTransactionMetadata(transaction);
@@ -45,7 +47,7 @@ export class TransactionDecoder {
       metadata.functionArgs = args;
     }
 
-    if (args.length === 0) {
+    if (args.length === 0 && !this.isSmartContract(transaction.receiver)) {
       metadata.functionName = 'transfer';
       metadata.functionArgs = undefined;
     }
@@ -247,10 +249,19 @@ export class TransactionDecoder {
     return bech32.encode('erd', words);
   }
 
+  private bech32Decode(address: string): string | undefined {
+    const decoded = bech32.decodeUnsafe(address);
+    return decoded ? Buffer.from(bech32.fromWords(decoded.words)).toString('hex') : undefined;
+  }
+
   private isAddressValid(address: string): boolean {
     return Buffer.from(address, "hex").length == 32;
   }
 
+  private isSmartContract(address: string): boolean {
+    return this.bech32Decode(address)?.startsWith(SMART_CONTRACT_HEX_PUBKEY_PREFIX) ?? false;
+  }
+
   private isSmartContractArgument(arg: string): boolean {
     if (!this.isHex(arg)) {
       return false;

diff --git a/test/decoder.test.ts b/test/decoder.test.ts
@@ -13,7 +13,25 @@ test('Simple wallet to wallet transfer with dummy data text', () => {
     sender: 'erd18w6yj09l9jwlpj5cjqq9eccfgulkympv7d4rj6vq4u49j8fpwzwsvx7e85',
     receiver: 'erd1lkrrrn3ws9sp854kdpzer9f77eglqpeet3e3k3uxvqxw9p3eq6xqxj43r9',
     value: BigInt('10000000000000000'),
-    functionName: 'transfer'
+    functionName: 'transfer',
+  });
+});
+
+test('Smart contract call without arguments', () => {
+  const decoder = new TransactionDecoder();
+  const metadata = decoder.getTransactionMetadata({
+    sender: 'erd18w6yj09l9jwlpj5cjqq9eccfgulkympv7d4rj6vq4u49j8fpwzwsvx7e85',
+    receiver: 'erd1qqqqqqqqqqqqqpgqmua7hcd05yxypyj7sv7pffrquy9gf86s535qxct34s',
+    data: 'bXlFbmRwb2ludA==',
+    value: '0',
+  });
+
+  expect(metadata).toEqual<TransactionMetadata>({
+    sender: 'erd18w6yj09l9jwlpj5cjqq9eccfgulkympv7d4rj6vq4u49j8fpwzwsvx7e85',
+    receiver: 'erd1qqqqqqqqqqqqqpgqmua7hcd05yxypyj7sv7pffrquy9gf86s535qxct34s',
+    value: BigInt('0'),
+    functionName: 'myEndpoint',
+    functionArgs: [],
   });
 });