fix: add isPendingTransactionStatus helper

src/types/index.ts

@@ -3,8 +3,8 @@
  * This is the main entry point for all type exports
  */
 
-export { TRANSACTION_STATUSES } from './transaction-status.ts';
-export type { TransactionStatus } from './transaction-status.ts';
+export { isPendingTransactionStatus, TRANSACTION_STATUSES } from './transaction-status.ts';
+export type { PendingTransactionStatus, TransactionStatus } from './transaction-status.ts';
 
 export type { Customer } from './customer.ts';
 

src/types/transaction-status.ts

@@ -26,3 +26,34 @@ export const TRANSACTION_STATUSES = [
 
 /** Union of all valid transaction statuses, pulled from the array above. */
 export type TransactionStatus = (typeof TRANSACTION_STATUSES)[number];
+
+/** Union of all pending transaction statuses. */
+export type PendingTransactionStatus = Extract<TransactionStatus, `pending_${string}`>;
+
+const PENDING_TRANSACTION_STATUSES: ReadonlySet<TransactionStatus> = new Set([
+  'pending_anchor',
+  'pending_user_transfer_start',
+  'pending_user_transfer_complete',
+  'pending_external',
+  'pending_trust',
+  'pending_user',
+  'pending_stellar',
+]);
+
+/**
+ * Returns whether a transaction is still in progress.
+ *
+ * Pending statuses are:
+ * - `pending_anchor`
+ * - `pending_user_transfer_start`
+ * - `pending_user_transfer_complete`
+ * - `pending_external`
+ * - `pending_trust`
+ * - `pending_user`
+ * - `pending_stellar`
+ */
+export function isPendingTransactionStatus(
+  status: TransactionStatus,
+): status is PendingTransactionStatus {
+  return PENDING_TRANSACTION_STATUSES.has(status);
+}

tests/types/transaction-status.test.ts

@@ -1,4 +1,9 @@
-import { TRANSACTION_STATUSES, type TransactionStatus } from '@/types/index.ts';
+import {
+  isPendingTransactionStatus,
+  type PendingTransactionStatus,
+  TRANSACTION_STATUSES,
+  type TransactionStatus,
+} from '@/types/index.ts';
 
 describe('TransactionStatus', () => {
   // -- runtime checks on the status array --
@@ -30,6 +35,47 @@ describe('TransactionStatus', () => {
     expect(unique.size).toBe(TRANSACTION_STATUSES.length);
   });
 
+  it('returns true for every pending or in-progress status', () => {
+    const pendingStatuses: TransactionStatus[] = [
+      'pending_anchor',
+      'pending_user_transfer_start',
+      'pending_user_transfer_complete',
+      'pending_external',
+      'pending_trust',
+      'pending_user',
+      'pending_stellar',
+    ];
+
+    expect(pendingStatuses.every((status) => isPendingTransactionStatus(status))).toBe(true);
+  });
+
+  it('returns false for every non-pending status', () => {
+    const nonPendingStatuses: TransactionStatus[] = [
+      'incomplete',
+      'completed',
+      'refunded',
+      'expired',
+      'error',
+      'no_market',
+      'too_small',
+      'too_large',
+    ];
+
+    expect(nonPendingStatuses.every((status) => !isPendingTransactionStatus(status))).toBe(true);
+  });
+
+  it('narrows to PendingTransactionStatus when the helper returns true', () => {
+    const status: TransactionStatus = 'pending_anchor';
+
+    if (isPendingTransactionStatus(status)) {
+      const narrowed: PendingTransactionStatus = status;
+      expect(narrowed).toBe('pending_anchor');
+      return;
+    }
+
+    throw new Error('expected status to narrow to PendingTransactionStatus');
+  });
+
   // -- compile-time checks (tsc catches these before tests even run) --
 
   it('accepts every valid status', () => {