Merge pull request #799 from Mimah97/feat/fix-simulation-typing

fix(backend): use SDK discriminated unions for simulate responses in …

Author: aji70

backend/src/subscriptions/subscription-chain-reader.service.spec.ts

@@ -0,0 +1,219 @@
+/**
+ * Unit tests for SubscriptionChainReaderService simulation typing.
+ *
+ * Covers every branch of the SDK discriminated union:
+ *   SimulateTransactionErrorResponse   → isSimulationError
+ *   SimulateTransactionSuccessResponse → isSimulationSuccess
+ *   SimulateTransactionRestoreResponse → isSimulationRestore
+ *
+ * Also verifies graceful handling of: network errors, missing retval,
+ * and the restore (archived entry) path.
+ */
+import { rpc, xdr, nativeToScVal } from '@stellar/stellar-sdk';
+import { SubscriptionChainReaderService } from './subscription-chain-reader.service';
+import { LedgerClockService } from './ledger-clock.service';
+
+// ── helpers ──────────────────────────────────────────────────────────────────
+
+const CONTRACT_ID = 'CAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAD2KM';
+const FAN     = 'GFAN1111111111111111111111111111111111111111111111111111';
+const CREATOR = 'GCREATOR111111111111111111111111111111111111111111111111';
+
+function makeService(simResult: rpc.Api.SimulateTransactionResponse): SubscriptionChainReaderService {
+  const ledgerClock = {
+    fetchSnapshot: jest.fn().mockResolvedValue({
+      ledgerSeq: 1000,
+      ledgerCloseTimeUnix: 1_700_000_000,
+      capturedAtMs: 1_700_000_000_000,
+      skewMs: -200,
+    }),
+    ledgerSeqToUnix: jest.fn().mockReturnValue(1_700_000_000 + 30 * 24 * 3600),
+  } as unknown as LedgerClockService;
+
+  const svc = new SubscriptionChainReaderService(ledgerClock);
+
+  // Stub the private makeServer() so no real network call is made
+  jest.spyOn(svc as any, 'makeServer').mockReturnValue({
+    simulateTransaction: jest.fn().mockResolvedValue(simResult),
+  });
+
+  return svc;
+}
+
+/** Build a minimal success response */
+function successSim(retval: xdr.ScVal): rpc.Api.SimulateTransactionSuccessResponse {
+  return {
+    _parsed: true,
+    id: '1',
+    latestLedger: 1000,
+    events: [],
+    transactionData: {} as any,
+    minResourceFee: '100',
+    result: { auth: [], retval },
+  } as rpc.Api.SimulateTransactionSuccessResponse;
+}
+
+/** Build a minimal error response */
+function errorSim(error: string): rpc.Api.SimulateTransactionErrorResponse {
+  return {
+    _parsed: true,
+    id: '1',
+    latestLedger: 1000,
+    events: [],
+    error,
+  } as rpc.Api.SimulateTransactionErrorResponse;
+}
+
+/** Build a minimal restore response */
+function restoreSim(): rpc.Api.SimulateTransactionRestoreResponse {
+  return {
+    _parsed: true,
+    id: '1',
+    latestLedger: 1000,
+    events: [],
+    transactionData: {} as any,
+    minResourceFee: '100',
+    result: { auth: [], retval: nativeToScVal(true) },
+    restorePreamble: { minResourceFee: '200', transactionData: {} as any },
+  } as rpc.Api.SimulateTransactionRestoreResponse;
+}
+
+// ── readIsSubscriber ──────────────────────────────────────────────────────────
+
+describe('SubscriptionChainReaderService.readIsSubscriber', () => {
+  it('returns ok=true isSubscriber=true on success sim with true retval', async () => {
+    const svc = makeService(successSim(nativeToScVal(true)));
+    const result = await svc.readIsSubscriber(CONTRACT_ID, FAN, CREATOR);
+    expect(result).toEqual({ ok: true, isSubscriber: true });
+  });
+
+  it('returns ok=true isSubscriber=false on success sim with false retval', async () => {
+    const svc = makeService(successSim(nativeToScVal(false)));
+    const result = await svc.readIsSubscriber(CONTRACT_ID, FAN, CREATOR);
+    expect(result).toEqual({ ok: true, isSubscriber: false });
+  });
+
+  it('returns ok=false with error string on error sim', async () => {
+    const svc = makeService(errorSim('contract not found'));
+    const result = await svc.readIsSubscriber(CONTRACT_ID, FAN, CREATOR);
+    expect(result.ok).toBe(false);
+    expect((result as any).error).toMatch(/contract not found/i);
+  });
+
+  it('returns ok=false with restore message on restore sim', async () => {
+    const svc = makeService(restoreSim());
+    const result = await svc.readIsSubscriber(CONTRACT_ID, FAN, CREATOR);
+    expect(result.ok).toBe(false);
+    expect((result as any).error).toMatch(/restoration/i);
+  });
+
+  it('returns ok=false when simulateTransaction rejects (network error)', async () => {
+    const svc = new SubscriptionChainReaderService({
+      fetchSnapshot: jest.fn(),
+      ledgerSeqToUnix: jest.fn(),
+    } as unknown as LedgerClockService);
+    jest.spyOn(svc as any, 'makeServer').mockReturnValue({
+      simulateTransaction: jest.fn().mockRejectedValue(new Error('connection refused')),
+    });
+    const result = await svc.readIsSubscriber(CONTRACT_ID, FAN, CREATOR);
+    expect(result.ok).toBe(false);
+    expect((result as any).error).toMatch(/connection refused/i);
+  });
+
+  it('returns ok=false when success sim has no retval', async () => {
+    const sim: rpc.Api.SimulateTransactionSuccessResponse = {
+      _parsed: true,
+      id: '1',
+      latestLedger: 1000,
+      events: [],
+      transactionData: {} as any,
+      minResourceFee: '100',
+      // result intentionally absent
+    } as rpc.Api.SimulateTransactionSuccessResponse;
+    const svc = makeService(sim);
+    const result = await svc.readIsSubscriber(CONTRACT_ID, FAN, CREATOR);
+    expect(result.ok).toBe(false);
+    expect((result as any).error).toMatch(/no retval/i);
+  });
+});
+
+// ── readExpiryUnix ────────────────────────────────────────────────────────────
+
+describe('SubscriptionChainReaderService.readExpiryUnix', () => {
+  it('returns ok=true with expiryUnix from contract when non-zero', async () => {
+    const contractExpiry = 1_800_000_000n;
+    const retval = nativeToScVal([1200n, contractExpiry] as any);
+    const svc = makeService(successSim(retval));
+    const result = await svc.readExpiryUnix(CONTRACT_ID, FAN, CREATOR);
+    expect(result.ok).toBe(true);
+    if (result.ok) {
+      expect(result.expiryUnix).toBe(Number(contractExpiry));
+      expect(typeof result.skewMs).toBe('number');
+    }
+  });
+
+  it('returns ok=false on error sim', async () => {
+    const svc = makeService(errorSim('host function error'));
+    const result = await svc.readExpiryUnix(CONTRACT_ID, FAN, CREATOR);
+    expect(result.ok).toBe(false);
+  });
+
+  it('returns ok=false on restore sim', async () => {
+    const svc = makeService(restoreSim());
+    const result = await svc.readExpiryUnix(CONTRACT_ID, FAN, CREATOR);
+    expect(result.ok).toBe(false);
+    expect((result as any).error).toMatch(/restoration/i);
+  });
+});
+
+// ── readPlan ──────────────────────────────────────────────────────────────────
+
+describe('SubscriptionChainReaderService.readPlan', () => {
+  it('returns ok=true with plan fields on success sim', async () => {
+    const planNative = { creator: CREATOR, asset: 'XLM', amount: 10_000_000n, interval_days: 30 };
+    const retval = nativeToScVal(planNative as any);
+    const svc = makeService(successSim(retval));
+    const result = await svc.readPlan(CONTRACT_ID, 1);
+    expect(result.ok).toBe(true);
+    if (result.ok) {
+      expect(result.plan.creator).toBe(CREATOR);
+      expect(result.plan.amount).toBe('10000000');
+      expect(result.plan.intervalDays).toBe(30);
+    }
+  });
+
+  it('returns ok=false on error sim', async () => {
+    const svc = makeService(errorSim('plan not found'));
+    const result = await svc.readPlan(CONTRACT_ID, 99);
+    expect(result.ok).toBe(false);
+  });
+
+  it('returns ok=false on restore sim', async () => {
+    const svc = makeService(restoreSim());
+    const result = await svc.readPlan(CONTRACT_ID, 1);
+    expect(result.ok).toBe(false);
+    expect((result as any).error).toMatch(/restoration/i);
+  });
+});
+
+// ── readPlanCount ─────────────────────────────────────────────────────────────
+
+describe('SubscriptionChainReaderService.readPlanCount', () => {
+  it('returns ok=true with count on success sim', async () => {
+    const svc = makeService(successSim(nativeToScVal(5, { type: 'u32' })));
+    const result = await svc.readPlanCount(CONTRACT_ID);
+    expect(result).toEqual({ ok: true, count: 5 });
+  });
+
+  it('returns ok=false on error sim', async () => {
+    const svc = makeService(errorSim('contract error'));
+    const result = await svc.readPlanCount(CONTRACT_ID);
+    expect(result.ok).toBe(false);
+  });
+
+  it('returns ok=false on restore sim', async () => {
+    const svc = makeService(restoreSim());
+    const result = await svc.readPlanCount(CONTRACT_ID);
+    expect(result.ok).toBe(false);
+  });
+});