Stabilize gateway reload/restart behavior and remove doctor --json dependency (#504)

tests/unit/gateway-restart-governor.test.ts

@@ -0,0 +1,106 @@
+import { describe, expect, it } from 'vitest';
+import { GatewayRestartGovernor } from '@electron/gateway/restart-governor';
+
+describe('GatewayRestartGovernor', () => {
+  it('suppresses restart during exponential cooldown window', () => {
+    const governor = new GatewayRestartGovernor({
+      baseCooldownMs: 1000,
+      maxCooldownMs: 8000,
+      maxRestartsPerWindow: 10,
+      windowMs: 60000,
+      stableResetMs: 60000,
+      circuitOpenMs: 60000,
+    });
+
+    expect(governor.decide(1000).allow).toBe(true);
+    governor.recordExecuted(1000);
+
+    const blocked = governor.decide(1500);
+    expect(blocked.allow).toBe(false);
+    expect(blocked.allow ? '' : blocked.reason).toBe('cooldown_active');
+    expect(blocked.allow ? 0 : blocked.retryAfterMs).toBeGreaterThan(0);
+
+    expect(governor.decide(3000).allow).toBe(true);
+  });
+
+  it('opens circuit after restart budget is exceeded', () => {
+    const governor = new GatewayRestartGovernor({
+      maxRestartsPerWindow: 2,
+      windowMs: 60000,
+      baseCooldownMs: 0,
+      maxCooldownMs: 0,
+      stableResetMs: 120000,
+      circuitOpenMs: 30000,
+    });
+
+    expect(governor.decide(1000).allow).toBe(true);
+    governor.recordExecuted(1000);
+    expect(governor.decide(2000).allow).toBe(true);
+    governor.recordExecuted(2000);
+
+    const budgetBlocked = governor.decide(3000);
+    expect(budgetBlocked.allow).toBe(false);
+    expect(budgetBlocked.allow ? '' : budgetBlocked.reason).toBe('budget_exceeded');
+
+    const circuitBlocked = governor.decide(4000);
+    expect(circuitBlocked.allow).toBe(false);
+    expect(circuitBlocked.allow ? '' : circuitBlocked.reason).toBe('circuit_open');
+
+    expect(governor.decide(62001).allow).toBe(true);
+  });
+
+  it('resets consecutive backoff after stable running period', () => {
+    const governor = new GatewayRestartGovernor({
+      baseCooldownMs: 1000,
+      maxCooldownMs: 8000,
+      maxRestartsPerWindow: 10,
+      windowMs: 600000,
+      stableResetMs: 5000,
+      circuitOpenMs: 60000,
+    });
+
+    governor.recordExecuted(0);
+    governor.recordExecuted(1000);
+    const blockedBeforeStable = governor.decide(2500);
+    expect(blockedBeforeStable.allow).toBe(false);
+    expect(blockedBeforeStable.allow ? '' : blockedBeforeStable.reason).toBe('cooldown_active');
+
+    governor.onRunning(3000);
+    const allowedAfterStable = governor.decide(9000);
+    expect(allowedAfterStable.allow).toBe(true);
+  });
+
+  it('resets time-based state when clock moves backwards', () => {
+    const governor = new GatewayRestartGovernor({
+      maxRestartsPerWindow: 2,
+      windowMs: 60000,
+      baseCooldownMs: 1000,
+      maxCooldownMs: 8000,
+      stableResetMs: 60000,
+      circuitOpenMs: 30000,
+    });
+
+    governor.recordExecuted(10_000);
+    governor.recordExecuted(11_000);
+    const blocked = governor.decide(11_500);
+    expect(blocked.allow).toBe(false);
+
+    // Simulate clock rewind and verify stale guard state does not lock out restarts.
+    const afterRewind = governor.decide(9_000);
+    expect(afterRewind.allow).toBe(true);
+  });
+
+  it('wraps counters safely at MAX_SAFE_INTEGER', () => {
+    const governor = new GatewayRestartGovernor();
+    (governor as unknown as { executedTotal: number; suppressedTotal: number }).executedTotal = Number.MAX_SAFE_INTEGER;
+    (governor as unknown as { executedTotal: number; suppressedTotal: number }).suppressedTotal = Number.MAX_SAFE_INTEGER;
+
+    governor.recordExecuted(1000);
+    governor.decide(1000);
+
+    expect(governor.getCounters()).toEqual({
+      executedTotal: 0,
+      suppressedTotal: 0,
+    });
+  });
+});