fix(abstract-eth): explainTransaction to return outputs array

modules/abstract-eth/src/lib/transaction.ts

@@ -130,6 +130,16 @@ export class Transaction extends BaseTransaction {
       if (signature !== '0x') {
         this._signatures.push(signature);
       }
+    } else if (this._type === TransactionType.SingleSigSend) {
+      // For single-sig sends, the recipient and amount are in the basic transaction fields
+      const coinName = this._coinConfig.name;
+      if (txData.to && txData.value) {
+        this.outputs.push({
+          address: txData.to,
+          value: txData.value,
+          coin: coinName,
+        });
+      }
     }
   }
 

modules/abstract-eth/test/unit/explainTransaction.test.ts

@@ -0,0 +1,51 @@
+import { BitGoAPI } from '@bitgo/sdk-api';
+import { Hteth } from '@bitgo/sdk-coin-eth';
+
+import * as should from 'should';
+
+describe('AbstractEthLikeCoin explainTransaction', function () {
+  let bitgo: BitGoAPI;
+  let hteth;
+
+  before(function () {
+    bitgo = new BitGoAPI({ env: 'test' });
+    bitgo.register('hteth', Hteth.createInstance);
+    hteth = bitgo.coin('hteth');
+  });
+
+  it('should explain a SingleSigSend transaction and return outputs', async function () {
+    const txHex =
+      '02f483088bb080830d4ae184012759d5830178749477aafabf1b7155f00292acf2be008e8fc9ef7b3a87038d7ea4c6800080c0808080';
+    const feeInfo = { fee: '974670461244' };
+
+    const explanation = await hteth.explainTransaction({
+      txHex,
+      feeInfo,
+    });
+
+    // Assertions to verify the bug is fixed
+    should.exist(explanation);
+    should.exist(explanation.id);
+    explanation.id.should.equal('0x84270a6ec4defc63ff8f37d4e1c5195e6772c634b89450864ecd5e6a8360b2d3');
+
+    should.exist(explanation.outputs);
+    explanation.outputs.should.be.an.Array();
+    explanation.outputs.length.should.equal(1, 'Should have exactly 1 output');
+
+    // Verify output details
+    const output = explanation.outputs[0];
+    output.address.should.equal('0x77aafabf1b7155f00292acf2be008e8fc9ef7b3a');
+    output.amount.should.equal('1000000000000000'); // 0.001 ETH
+
+    // Verify output amount
+    explanation.outputAmount.should.equal('1000000000000000');
+
+    // Verify change outputs (should be empty for ETH)
+    explanation.changeOutputs.should.be.an.Array();
+    explanation.changeOutputs.length.should.equal(0);
+    explanation.changeAmount.should.equal('0');
+
+    // Verify fee
+    explanation.fee.should.equal(feeInfo);
+  });
+});