Address review feedback

Author: catamorphism

polyfill/lib/calendar.mjs

@@ -1041,13 +1041,13 @@ const nonIsoHelperBase = {
       case 'month':
       case 'year': {
         // Sign is -1 if calendarTwo < calendarOne, 1 if calendarTwo > calendarOne
-        let sign = this.compareCalendarDates(calendarTwo, calendarOne);
+        const sign = this.compareCalendarDates(calendarTwo, calendarOne);
         // If dates are equal, return 0 date duration
         if (!sign) {
           return { years: 0, months: 0, weeks: 0, days: 0 };
         }
         // Take the difference between the years of the two dates
-        let diffYears = calendarTwo.year - calendarOne.year;
+        const diffYears = calendarTwo.year - calendarOne.year;
         // Take the difference between the days of the two dates
         const diffDays = calendarTwo.day - calendarOne.day;
         // Get list of additional months, and possibly cycle info
@@ -1062,7 +1062,7 @@ const nonIsoHelperBase = {
           // then the years difference should be positive (or negative if sign < 0).
           if (calendarTwo.monthCode > calendarOne.monthCode) diffInYearSign = 1;
           // If calendarTwo's month is less than calendarOne's month,
-          // then the years difference should be positive (or negative if sign < 0).
+          // then the years difference should be negative (or positive if sign < 0).
           if (calendarTwo.monthCode < calendarOne.monthCode) diffInYearSign = -1;
           // If the two months are equal, the sign of the years difference should be
           // the sign of the days difference.
@@ -1087,7 +1087,7 @@ const nonIsoHelperBase = {
 
         // intermediate should be a date between calendarOne and calendarTwo,
         // that is within a year of calendarTwo.
-        let intermediate =
+        const intermediate =
           years || months ? this.addCalendar(calendarOne, { years, months }, 'constrain', cache) : calendarOne;
 
         // At this point, intermediate could fail to be in between calendarOne and calendarTwo
@@ -1120,7 +1120,7 @@ const nonIsoHelperBase = {
 
         // This may return a duration like <P12M11D> that appears to have unbalanced months.
         // But that's fine, because subtracting <P12M11D> from a date may have different
-        // results than subtracting <P1Y11D> from the same date, in the presence of leap years.
+        // results than subtracting <P1Y11D> from the same date, in the presence of leap months.
         break;
       }
     }