test(sdk-coin-xlm): add ALPHANUM12 enabletoken verification tests for TUSDC

prajwalu142 · bitgobot · commit 2c4e10617c41 · 2026-08-11T17:04:56.000Z
Add three unit tests exercising the ALPHANUM12 (5-char asset code) path through verifyTransaction/verifyTrustlineTxOperations in sdk-coin-xlm. All prior test fixtures only covered ALPHANUM4 (≤4 char) asset codes; TUSDC is 5 chars and is encoded as assetTypeCreditAlphanum12 in Stellar XDR, which is a distinct code path that was previously untested. Tests added: 1. Happy path: changeTrust XDR for stellar.Asset('TUSDC', issuer) is accepted by verifyTransaction with matching enabletoken txParams. 2. Issuer mismatch: changeTrust from a different issuer is rejected with the expected "Invalid issuer on token enablement operation" error. 3. Code mismatch: changeTrust for 'USDCX' (also ALPHANUM12) while params expect 'TUSDC' is rejected with the expected code-mismatch error. These tests exercise the same issuer identified in CSHLD-1407/CSHLD-1447 (GC26PEYGETD7L6PUW2VCU3PSC7LCLRRPOSUILSHD2RT23IQUEAN4TQBQ) and confirm the SDK's XLM token verification pipeline handles ALPHANUM12 assets. Ticket: CSHLD-1447 Session-Id: bb58b0aa-c314-4212-8901-e1cfc7a3c8db Task-Id: 31db5ad2-ab59-4d9f-8c21-6acc91a05c08
diff --git a/modules/sdk-coin-xlm/test/unit/xlm.ts b/modules/sdk-coin-xlm/test/unit/xlm.ts
@@ -1016,6 +1016,75 @@ describe('XLM:', function () {
     });
   });
 
+  describe('ALPHANUM12 token (txlm:TUSDC) enabletoken verification', function () {
+    // TUSDC is a 5-char asset code — encoded as assetTypeCreditAlphanum12 in Stellar XDR.
+    // All prior test fixtures use 3–4 char (ALPHANUM4) codes; these tests verify that the
+    // verifyTransaction path handles the ALPHANUM12 encoding correctly (CSHLD-1447).
+    const stellarNetworkPassphrase = stellar.Networks.TESTNET;
+    const sourceAddress = 'GA34NPQ4M54HHZBKSDZ5B3J3BZHTXKCZD4UFO2OYZERPOASK4DAATSIB';
+    const tusdcIssuer = 'GC26PEYGETD7L6PUW2VCU3PSC7LCLRRPOSUILSHD2RT23IQUEAN4TQBQ';
+    const tusdcTokenName = `txlm:TUSDC-${tusdcIssuer}`;
+    const tusdcAsset = new stellar.Asset('TUSDC', tusdcIssuer);
+
+    const buildTxBase64 = (ops: stellar.xdr.Operation[]): string => {
+      const sourceAccount = new stellar.Account(sourceAddress, '1');
+      const tx = new stellar.TransactionBuilder(sourceAccount, {
+        fee: '100',
+        networkPassphrase: stellarNetworkPassphrase,
+      });
+      ops.forEach((op) => tx.addOperation(op));
+      return tx.setTimeout(0).build().toEnvelope().toXDR('base64');
+    };
+
+    it('should verify a changeTrust for a 5-char ALPHANUM12 asset (TUSDC)', async function () {
+      const txPrebuild = {
+        txBase64: buildTxBase64([stellar.Operation.changeTrust({ asset: tusdcAsset })]),
+      };
+      const txParams = {
+        type: 'enabletoken',
+        recipients: [{ tokenName: tusdcTokenName, amount: 0, address: '' }],
+      };
+      const isValid = await basecoin.verifyTransaction({
+        txParams,
+        txPrebuild,
+        wallet: {},
+        verification: { verifyTokenEnablement: true },
+      });
+      isValid.should.equal(true);
+    });
+
+    it('should reject a changeTrust whose issuer does not match txlm:TUSDC', async function () {
+      const differentIssuer = 'GCWHAO4SVB4KX3Q62QZGZUHUH2GSH3OIV7IS7Y3MPQOFGQFGBP6IYCOU';
+      const differentAsset = new stellar.Asset('TUSDC', differentIssuer);
+      const txPrebuild = {
+        txBase64: buildTxBase64([stellar.Operation.changeTrust({ asset: differentAsset })]),
+      };
+      const txParams = {
+        type: 'enabletoken',
+        recipients: [{ tokenName: tusdcTokenName, amount: 0, address: '' }],
+      };
+      await basecoin
+        .verifyTransaction({ txParams, txPrebuild, wallet: {}, verification: { verifyTokenEnablement: true } })
+        .should.be.rejectedWith(
+          `Invalid issuer on token enablement operation: expected ${tusdcIssuer}, got ${differentIssuer}`
+        );
+    });
+
+    it('should reject a changeTrust whose asset code does not match TUSDC', async function () {
+      const wrongAsset = new stellar.Asset('USDCX', tusdcIssuer);
+      const txPrebuild = {
+        txBase64: buildTxBase64([stellar.Operation.changeTrust({ asset: wrongAsset })]),
+      };
+      const txParams = {
+        type: 'enabletoken',
+        recipients: [{ tokenName: tusdcTokenName, amount: 0, address: '' }],
+      };
+      await basecoin
+        .verifyTransaction({ txParams, txPrebuild, wallet: {}, verification: { verifyTokenEnablement: true } })
+        .should.be.rejectedWith('Invalid token code on token enablement operation: expected TUSDC, got USDCX');
+    });
+  });
+
   describe('Federation lookups:', function () {
     describe('Look up by stellar address:', function () {
       it('should fail to loop up an invalid stellar address with a bitgo.com domain', async function () {
