import { describe, expect, it } from "vitest"; import {  DEFAULT_RECONNECT_BACKOFF,  getReconnectDelayMs,  type ReconnectBackoffConfig,} from "./reconnectBackoff.ts"; describe("getReconnectDelayMs", () => {  it("returns exponential delays with default config", () => {    expect(getReconnectDelayMs(0)).toBe(1_000);    expect(getReconnectDelayMs(1)).toBe(2_000);    expect(getReconnectDelayMs(2)).toBe(4_000);    expect(getReconnectDelayMs(3)).toBe(8_000);    expect(getReconnectDelayMs(4)).toBe(16_000);    expect(getReconnectDelayMs(5)).toBe(32_000);    expect(getReconnectDelayMs(6)).toBe(64_000);  });   it("returns null when retry index exceeds maxRetries", () => {    expect(getReconnectDelayMs(7)).toBeNull();    expect(getReconnectDelayMs(100)).toBeNull();  });   it("returns null for negative indices", () => {    expect(getReconnectDelayMs(-1)).toBeNull();  });   it("returns null for non-integer indices", () => {    expect(getReconnectDelayMs(1.5)).toBeNull();  });   it("caps delay at maxDelayMs", () => {    const config: ReconnectBackoffConfig = {      initialDelayMs: 10_000,      backoffFactor: 10,      maxDelayMs: 30_000,      maxRetries: 5,    };     expect(getReconnectDelayMs(0, config)).toBe(10_000);    expect(getReconnectDelayMs(1, config)).toBe(30_000); // 100_000 capped to 30_000    expect(getReconnectDelayMs(2, config)).toBe(30_000); // 1_000_000 capped to 30_000  });   it("supports unlimited retries when maxRetries is null", () => {    const config: ReconnectBackoffConfig = {      ...DEFAULT_RECONNECT_BACKOFF,      maxRetries: null,    };     expect(getReconnectDelayMs(0, config)).toBe(1_000);    expect(getReconnectDelayMs(50, config)).toBe(64_000); // capped at maxDelayMs    expect(getReconnectDelayMs(100, config)).toBe(64_000);  });}); describe("DEFAULT_RECONNECT_BACKOFF", () => {  it("has sensible defaults", () => {    expect(DEFAULT_RECONNECT_BACKOFF.initialDelayMs).toBe(1_000);    expect(DEFAULT_RECONNECT_BACKOFF.backoffFactor).toBe(2);    expect(DEFAULT_RECONNECT_BACKOFF.maxDelayMs).toBe(64_000);    expect(DEFAULT_RECONNECT_BACKOFF.maxRetries).toBe(7);  });});