GregorianCalendarHelper, suspicious % operator

[VasilievSerg]

Link to the sources

public int ToFourDigitYear(int year, int twoDigitYearMax)
{
    if (year < 0)
    {
        throw new ArgumentOutOfRangeException(nameof(year),
            SR.ArgumentOutOfRange_NeedPosNum);
    }

    if (year < 100)
    {
        int y = year % 100; // <=
        return (twoDigitYearMax / 100 - (y > twoDigitYearMax % 100 ? 1 : 0)) * 100 + y;
    }
    ....
}

The y and year variables are always equal.
Since year's value is in range [0, 99], the result of the year % 100 expression is always equal to year.

I'm not sure whether the marked statement is redundant or it is an error.

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Issue Details

---

Link to the sources

public int ToFourDigitYear(int year, int twoDigitYearMax)
{
    if (year < 0)
    {
        throw new ArgumentOutOfRangeException(nameof(year),
            SR.ArgumentOutOfRange_NeedPosNum);
    }

    if (year < 100)
    {
        int y = year % 100; // <=
        return (twoDigitYearMax / 100 - (y > twoDigitYearMax % 100 ? 1 : 0)) * 100 + y;
    }
    ....
}

The y and year variables are always equal.
Since year's value is in range [0, 99], the result of the year % 100 expression is always equal to year.

I'm not sure whether the marked statement is redundant or it is an error.

Author:	VasilievSerg
Assignees:	-
Labels:	area-System.Globalization, untriaged
Milestone:	-