Merge pull request #2 from LordZardeck/fix/dates-with-time

Fix issue with dates not being tracked from start of day

build.ts

@@ -0,0 +1,6 @@
+// @ts-ignore
+await Bun.build({
+	entrypoints: ['./src/index.ts'],
+	outdir: './dist',
+	minify: true,
+})

package.json

@@ -7,7 +7,7 @@
   "scripts": {
     "lint": "bunx eslint ./src/*.ts --fix",
     "watch": "bunx tsc -p tsconfig.json --watch",
-    "build": "bunx rimraf dist && bunx tsc -p tsconfig.json",
+    "build": "bunx rimraf dist && bun build.ts && bunx tsc --emitDeclarationOnly",
     "test": "bun test",
     "coverage": "bun test --coverage"
   },

src/AbstractLoanSchedule.ts

@@ -9,6 +9,7 @@ import {
 	endOfMonth,
 	isSameYear,
 	setDate,
+	startOfDay,
 	startOfMonth,
 } from 'date-fns'
 
@@ -33,7 +34,7 @@ export function getInterestByPeriod({ rate, to, from, amount }: InterestParamete
 }
 
 export function getPaymentDate(issueDate: Date, scheduleMonth: number, paymentDay: number): Date {
-	const paymentDate = addMonths(startOfMonth(issueDate), scheduleMonth)
+	const paymentDate = addMonths(startOfMonth(startOfDay(issueDate)), scheduleMonth)
 	const paymentEndOfMonth = endOfMonth(paymentDate)
 
 	return setDate(
@@ -126,8 +127,8 @@ export function calculateSchedule<P extends Payment = Payment>(
 	const minPaymentAmount = Decimal.min(firstPayment.paymentAmount, lastPayment.paymentAmount).toFixed(fixedDecimal)
 	const maxPaymentAmount = Decimal.max(firstPayment.paymentAmount, lastPayment.paymentAmount).toFixed(fixedDecimal)
 
-	const dateStart = setDate(initialPayment.paymentDate, 1)
-	const dateEnd = setDate(lastPayment.paymentDate, 1)
+	const dateStart = setDate(startOfDay(initialPayment.paymentDate), 1)
+	const dateEnd = setDate(startOfDay(lastPayment.paymentDate), 1)
 
 	const term = differenceInMonths(dateEnd, dateStart)
 

src/AnnuityLoanSchedule.ts

@@ -8,7 +8,7 @@ import {
 	getPaymentDateOnWorkingDay,
 } from './AbstractLoanSchedule'
 import { Payment, PaymentType, Schedule, ScheduleConfig, ScheduleOptions } from './types'
-import { isAfter, isSameDay } from 'date-fns'
+import { isAfter, isSameDay, startOfDay } from 'date-fns'
 import ProdCal from 'prod-cal'
 
 export type AnnuityPayment = Payment & {
@@ -34,7 +34,7 @@ export function generateAnnuityPayments(parameters: ScheduleConfig, options?: Sc
 
 	const payments: Array<AnnuityPayment> = [
 		{
-			...createInitialPayment(amount, issueDate, rate),
+			...createInitialPayment(amount, startOfDay(issueDate), rate),
 			annuityPaymentAmount: 0,
 		},
 	]
@@ -43,7 +43,7 @@ export function generateAnnuityPayments(parameters: ScheduleConfig, options?: Sc
 		.map(Number.call, Number)
 		.map((termMonth) => ({
 			paymentDate: getPaymentDateOnWorkingDay(
-				termMonth === 0 ? new Date(issueDate) : getPaymentDate(issueDate, termMonth, paymentOnDay),
+				termMonth === 0 ? startOfDay(issueDate) : getPaymentDate(issueDate, termMonth, paymentOnDay),
 				isHoliday,
 			),
 			paymentType: PaymentType.ER_TYPE_REGULAR,

src/BubbleLoanSchedule.ts

@@ -1,7 +1,7 @@
 import Decimal from 'decimal.js'
 import { calculateInterestByPeriod, calculateSchedule, createInitialPayment } from './AbstractLoanSchedule'
 import { ScheduleOptions, ScheduleConfig, Payment } from './types'
-import { addMonths, setDate } from 'date-fns'
+import { addMonths, setDate, startOfDay } from 'date-fns'
 
 export function generateBubblePayments(parameters: ScheduleConfig, options?: ScheduleOptions) {
 	const fixedDecimal = options?.decimalDigit ?? 2
@@ -38,7 +38,7 @@ export function generateBubblePayments(parameters: ScheduleConfig, options?: Sch
 				},
 			]
 		},
-		[createInitialPayment(amount, issueDate, rate)] as Payment[],
+		[createInitialPayment(amount, startOfDay(issueDate), rate)] as Payment[],
 	)
 }
 

src/DifferentiatedLoanSchedule.ts

@@ -1,7 +1,7 @@
 import Decimal from 'decimal.js'
 import { calculateInterestByPeriod, calculateSchedule, createInitialPayment } from './AbstractLoanSchedule'
 import { ScheduleOptions, ScheduleConfig, Payment } from './types'
-import { addMonths, setDate } from 'date-fns'
+import { addMonths, setDate, startOfDay } from 'date-fns'
 
 export function generateDifferentiatedPayments(parameters: ScheduleConfig, options?: ScheduleOptions) {
 	const fixedDecimal = options?.decimalDigit ?? 2
@@ -39,7 +39,7 @@ export function generateDifferentiatedPayments(parameters: ScheduleConfig, optio
 				},
 			]
 		},
-		[createInitialPayment(amount, issueDate, rate)] as Payment[],
+		[createInitialPayment(amount, startOfDay(issueDate), rate)] as Payment[],
 	)
 }
 

test/AbstractLoanSchedule.spec.ts

@@ -1,40 +1,119 @@
-import { describe, expect, mock, test } from 'bun:test'
-import { createHolidayChecker, getPaymentDate, getPaymentDateOnWorkingDay, printSchedule } from '../src'
+import { describe, expect, mock, it } from 'bun:test'
+import {
+	calculateSchedule,
+	createHolidayChecker,
+	generateAnnuityPayments,
+	getPaymentDate,
+	getPaymentDateOnWorkingDay,
+	printSchedule,
+	ScheduleConfig,
+} from '../src'
 import ProdCal from 'prod-cal'
 
-describe('AbstractLoan should', () => {
-	test('print Schedule', () => {
-		const printFunction = mock(() => false)
-
-		printSchedule(
-			{
-				overAllInterest: 0,
-				amount: 0,
-				fullAmount: 0,
-				term: 0,
-				minPaymentAmount: 0,
-				maxPaymentAmount: 0,
-				payments: [],
-				efficientRate: 0,
-			},
-			printFunction,
-		)
-		expect(printFunction).toHaveBeenCalled()
-	})
-
-	test('add month and closest day', () => {
+describe('AbstractLoan', () => {
+	it('should add month and closest day', () => {
 		expect(getPaymentDate(new Date(2013, 4, 1), 33, 31).getTime()).toEqual(new Date(2016, 1, 29).getTime())
 	})
 
-	test('return payment date as next day after holiday', () => {
+	it('should return payment date as next day after holiday', () => {
 		expect(
 			getPaymentDateOnWorkingDay(new Date(2015, 4, 1), createHolidayChecker(new ProdCal('ru'))).getTime(),
 		).toEqual(new Date(2015, 4, 5).getTime())
 	})
 
-	test('return payment date as closet day before holiday if holiday lasts to the end of the month', () => {
+	it('should return payment date as closet day before holiday if holiday lasts to the end of the month', () => {
 		expect(
 			getPaymentDateOnWorkingDay(new Date(2015, 4, 31), createHolidayChecker(new ProdCal('ru'))).getTime(),
 		).toEqual(new Date(2015, 4, 29).getTime())
 	})
+
+	describe('printSchedule', () => {
+		it('should print Schedule', () => {
+			const printFunction = mock(() => false)
+
+			printSchedule(
+				{
+					overAllInterest: 0,
+					amount: 0,
+					fullAmount: 0,
+					term: 0,
+					minPaymentAmount: 0,
+					maxPaymentAmount: 0,
+					payments: [],
+					efficientRate: 0,
+				},
+				printFunction,
+			)
+			expect(printFunction).toHaveBeenCalled()
+		})
+	})
+
+	describe('calculateSchedule', () => {
+		it('should require at least 2 payment records', () => {
+			expect(() =>
+				calculateSchedule(
+					{
+						amount: 500000,
+						rate: 11.5,
+						term: 12,
+						paymentOnDay: 25,
+						issueDate: new Date(2018, 9, 25),
+					},
+					[],
+				),
+			).toThrow()
+		})
+
+		describe('should return the same term length specified', () => {
+			it('when no payment amount is specified', () => {
+				const config: ScheduleConfig = {
+					amount: 26000,
+					rate: 18,
+					term: 60,
+					paymentOnDay: 25,
+					issueDate: new Date(2018, 9, 25),
+				}
+				const schedule = calculateSchedule(config, generateAnnuityPayments(config))
+				expect(schedule.term).toEqual(60)
+			})
+			it('when no payment amount is specified and date has time', () => {
+				const config: ScheduleConfig = {
+					amount: 26000,
+					rate: 18,
+					term: 60,
+					paymentOnDay: 25,
+					issueDate: new Date(2018, 9, 25, 6, 0, 0),
+				}
+				const schedule = calculateSchedule(config, generateAnnuityPayments(config))
+				expect(schedule.term).toEqual(60)
+			})
+
+			it('when payment amount is specified', () => {
+				const config: ScheduleConfig = {
+					amount: 26000,
+					rate: 18,
+					term: 60,
+					paymentOnDay: 22,
+					paymentAmount: 660.23,
+					issueDate: new Date(2024, 0, 22),
+					earlyRepayment: [],
+				}
+				const schedule = calculateSchedule(config, generateAnnuityPayments(config))
+				expect(schedule.term).toEqual(60)
+			})
+			it('when payment amount is specified and date has time', () => {
+				const config: ScheduleConfig = {
+					amount: 26000,
+					rate: 18,
+					term: 60,
+					paymentOnDay: 22,
+					paymentAmount: 660.23,
+					issueDate: new Date(2024, 0, 22, 6, 0, 0),
+					earlyRepayment: [],
+				}
+				const schedule = calculateSchedule(config, generateAnnuityPayments(config))
+				expect(schedule.term).toEqual(60)
+			})
+		})
+	})
 })