describe('IOEither practical', () => {
  it('loads valid config', () => {
    const result = loadConfig('dev')()
    expect(E.isRight(result)).toBe(true)
    if (E.isRight(result)) {
      expect(result.right).toEqual({ timeout: 5000, retries: 3 })
    }
  })

  it('fails on missing config', () => {
    const result = loadConfig('staging')()
    expect(E.isLeft(result)).toBe(true)
  })

  it('validates config successfully', () => {
    const config: Config = { timeout: 5000, retries: 3 }
    const result = validateConfig(config)()
    expect(E.isRight(result)).toBe(true)
  })

  it('fails validation for invalid config', () => {
    const config: Config = { timeout: -1, retries: 3 }
    const result = validateConfig(config)()
    expect(E.isLeft(result)).toBe(true)
  })

  it('loads and validates config', () => {
    const result = loadAndValidateConfig('prod')()
    expect(E.isRight(result)).toBe(true)
  })
})