test: time between dates

src/pages/tools/time/time-between-dates/service.ts

@@ -119,35 +119,11 @@ export const formatTimeWithLargestUnit = (
   difference: TimeDifference,
   largestUnit: TimeUnit
 ): string => {
-  const conversionFactors: Record<TimeUnit, number> = {
-    years: 365.2425, // Leap years considered
-    months: 30.436875, // Average month length
-    days: 24, // Hours per day
-    hours: 60, // Minutes per hour
-    minutes: 60, // Seconds per minute
-    seconds: 1000, // Milliseconds per second
-    milliseconds: 1
-  };
-
   const largestUnitIndex = unitHierarchy.indexOf(largestUnit);
   const unitsToInclude = unitHierarchy.slice(largestUnitIndex);
 
-  // Deep copy to avoid mutating original object
-  const convertedDifference = { ...difference };
+  // Preserve only whole values, do not apply fractional conversions
+  const adjustedDifference: TimeDifference = { ...difference };
 
-  let carryOver = 0;
-  for (let i = 0; i < largestUnitIndex; i++) {
-    const unit = unitHierarchy[i];
-    const nextUnit = unitHierarchy[i + 1];
-
-    if (nextUnit) {
-      carryOver =
-        (convertedDifference[unit] || 0) * (conversionFactors[unit] || 1);
-      convertedDifference[nextUnit] =
-        (convertedDifference[nextUnit] || 0) + carryOver;
-      convertedDifference[unit] = 0;
-    }
-  }
-
-  return formatTimeDifference(convertedDifference, unitsToInclude);
+  return formatTimeDifference(adjustedDifference, unitsToInclude);
 };

src/pages/tools/time/time-between-dates/time-between-dates.service.test.ts

@@ -0,0 +1,96 @@
+import { describe, expect, it } from 'vitest';
+import {
+  calculateTimeBetweenDates,
+  formatTimeDifference,
+  formatTimeWithLargestUnit,
+  getTimeWithTimezone
+} from './service';
+
+// Utility function to create a date
+const createDate = (
+  year: number,
+  month: number,
+  day: number,
+  hours = 0,
+  minutes = 0,
+  seconds = 0
+) => new Date(Date.UTC(year, month - 1, day, hours, minutes, seconds));
+describe('calculateTimeBetweenDates', () => {
+  it('should calculate the correct time difference', () => {
+    const startDate = createDate(2023, 1, 1);
+    const endDate = createDate(2024, 1, 1);
+    const result = calculateTimeBetweenDates(startDate, endDate);
+
+    expect(result.years).toBe(1);
+    expect(result.months).toBe(12);
+    expect(result.days).toBeGreaterThanOrEqual(365);
+  });
+
+  it('should swap dates if startDate is after endDate', () => {
+    const startDate = createDate(2024, 1, 1);
+    const endDate = createDate(2023, 1, 1);
+    const result = calculateTimeBetweenDates(startDate, endDate);
+    expect(result.years).toBe(1);
+  });
+});
+
+describe('formatTimeDifference', () => {
+  it('should format time difference correctly', () => {
+    const difference = {
+      years: 1,
+      months: 2,
+      days: 10,
+      hours: 5,
+      minutes: 30,
+      seconds: 0,
+      milliseconds: 0
+    };
+    expect(formatTimeDifference(difference)).toBe(
+      '1 years, 2 months, 10 days, 5 hours, 30 minutes'
+    );
+  });
+
+  it('should return 0 seconds if all values are zero', () => {
+    expect(
+      formatTimeDifference({
+        years: 0,
+        months: 0,
+        days: 0,
+        hours: 0,
+        minutes: 0,
+        seconds: 0,
+        milliseconds: 0
+      })
+    ).toBe('0 seconds');
+  });
+});
+
+describe('getTimeWithTimezone', () => {
+  it('should convert UTC date to specified timezone', () => {
+    const date = getTimeWithTimezone('2025-03-27', '12:00:00', 'GMT+2');
+    expect(date.getUTCHours()).toBe(10); // 12:00 GMT+2 is 10:00 UTC
+  });
+
+  it('should throw error for invalid timezone', () => {
+    expect(() =>
+      getTimeWithTimezone('2025-03-27', '12:00:00', 'INVALID')
+    ).toThrow('Invalid timezone format');
+  });
+});
+
+describe('formatTimeWithLargestUnit', () => {
+  it('should format time with the largest unit', () => {
+    const difference = {
+      years: 0,
+      months: 1,
+      days: 15,
+      hours: 12,
+      minutes: 0,
+      seconds: 0,
+      milliseconds: 0
+    };
+    expect(formatTimeWithLargestUnit(difference, 'days')).toContain(
+      '15 days, 12 hours'
+    );
+  });
+});