Phase6

packages/scheduler/src/scheduling.test.ts

@@ -0,0 +1,56 @@
+import { describe, expect, it } from 'vitest';
+
+import {
+  canAllocateOnNode,
+  canStartOnNode,
+  selectNodeForAllocation,
+} from './index';
+import type { NodeSnapshot } from './types';
+
+function node(partial: Partial<NodeSnapshot> & Pick<NodeSnapshot, 'id'>): NodeSnapshot {
+  return {
+    status: 'ONLINE',
+    maxServers: 10,
+    maxRamMb: 16384,
+    platformRamMb: 2048,
+    activeServers: 0,
+    lastHeartbeatAt: new Date(),
+    reservedRamMb: 0,
+    activeAllocationCount: 0,
+    ...partial,
+  };
+}
+
+describe('scheduler capacity', () => {
+  it('rejects maintenance and draining nodes for new allocations', () => {
+    const maintenance = node({ id: 'a', status: 'MAINTENANCE' });
+    const draining = node({ id: 'b', status: 'DRAINING' });
+
+    expect(canAllocateOnNode(maintenance, 1024)).toBe(false);
+    expect(canAllocateOnNode(draining, 1024)).toBe(false);
+    expect(canStartOnNode(draining, 1024)).toBe(true);
+  });
+
+  it('picks the least loaded node for placement', () => {
+    const lightlyLoaded = node({ id: 'light', reservedRamMb: 1024 });
+    const heavilyLoaded = node({ id: 'heavy', reservedRamMb: 8192 });
+
+    const selected = selectNodeForAllocation(
+      [heavilyLoaded, lightlyLoaded],
+      2048,
+    );
+
+    expect(selected?.id).toBe('light');
+  });
+
+  it('returns null when no node has enough RAM', () => {
+    const saturated = node({
+      id: 'full',
+      reservedRamMb: 14000,
+      maxRamMb: 16384,
+      platformRamMb: 2048,
+    });
+
+    expect(selectNodeForAllocation([saturated], 4096)).toBeNull();
+  });
+});