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import * as f from '../src/'
describe('Source code docs examples', () => {  test('fv()', () => {    expect(f.fv(0.05 / 12, 10 * 12, -100, -100)).toBeCloseTo(15692.928894335748, 6)  })
  test('pmt()', () => {    expect(f.pmt(0.075 / 12, 12 * 15, 200000)).toBeCloseTo(-1854.0247200054619, 6)  })
  test('nper()', () => {    expect(f.nper(0.07 / 12, -150, 8000)).toBeCloseTo(64.07334877066185, 6)  })
  test('ipmt()', () => {    const principal = 2500    const periods = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]    const ipmts = periods.map((per) => f.ipmt(0.0824 / 12, per, 1 * 12, principal))    expect(ipmts).toEqual([      -17.166666666666668,      -15.789337457350777,      -14.402550587464257,      -13.006241114404524,      -11.600343649629737,      -10.18479235559687,      -8.759520942678298,      -7.324462666057678,      -5.879550322604295,      -4.424716247725826,      -2.9598923121998877,      -1.4850099189833388    ])    const interestpd = ipmts.reduce((a, b) => a + b, 0)    expect(interestpd).toBeCloseTo(-112.98308424136215, 6)  })
  test('pv()', () => {    expect(f.pv(0.05 / 12, 10 * 12, -100, 15692.93)).toBeCloseTo(-100.00067131625819, 6)  })
  test('irr()', () => {    expect(f.irr([-100, 39, 59, 55, 20])).toBeCloseTo(0.2809484, 6)    expect(f.irr([-100, 0, 0, 74])).toBeCloseTo(-0.0954958, 6)    expect(f.irr([-100, 100, 0, -7])).toBeCloseTo(-0.083300, 6)    expect(f.irr([-100, 100, 0, 7])).toBeCloseTo(0.0620584, 6)    expect(f.irr([-5, 10.5, 1, -8, 1])).toBeCloseTo(0.088598, 6)  })
  test('npv()', () => {    const rate = 0.08    const cashflows = [-40_000, 5000, 8000, 12000, 30000]    expect(f.npv(rate, cashflows)).toBeCloseTo(3065.22266817, 6)
    const initialCashflow = cashflows[0]    cashflows[0] = 0    expect(f.npv(rate, cashflows) + initialCashflow).toBeCloseTo(3065.22266817, 6)  })})