Initial commit

tests/installation-limiter.test.ts

@@ -0,0 +1,23 @@
+import { describe, expect, it } from 'vitest'
+import { InstallationLimiter } from '../src/server/installation-limiter.js'
+
+describe('InstallationLimiter', () => {
+  it('enforces a bounded window independently per installation', () => {
+    const limiter = new InstallationLimiter(2, 1_000)
+    expect(limiter.consume('first', 0)).toBe(true)
+    expect(limiter.consume('first', 1)).toBe(true)
+    expect(limiter.consume('first', 2)).toBe(false)
+    expect(limiter.consume('second', 2)).toBe(true)
+    expect(limiter.consume('first', 1_000)).toBe(true)
+  })
+
+  it('fails closed when too many active installation counters exist', () => {
+    const limiter = new InstallationLimiter(2, 1_000)
+    for (let index = 0; index < 10_000; index += 1) {
+      expect(limiter.consume(`installation-${index}`, 0)).toBe(true)
+    }
+    expect(limiter.consume('overflow', 1)).toBe(false)
+    expect(limiter.consume('installation-0', 1)).toBe(true)
+    expect(limiter.consume('overflow', 1_000)).toBe(true)
+  })
+})