got := releaseTimeToReleaseTag(testCase.t)
			if got != testCase.tag && testCase.errStr == "" {
				t.Errorf("Test %d: Expected %v but got %v", i+1, testCase.tag, got)
			}
		}
		tagTime, err := releaseTagToReleaseTime(testCase.tag)
		if err != nil && err.Error() != testCase.errStr {
			t.Errorf("Test %d: Expected %v but got %v", i+1, testCase.errStr, err.Error())
		}
		if err == nil && !tagTime.Equal(testCase.t) {

// `RELEASE.2017-09-29T19-16-56Z`
func releaseTimeToReleaseTag(releaseTime time.Time) string {
	return "RELEASE." + releaseTime.Format(MinioReleaseTagTimeLayout)
}

// releaseTagToReleaseTime - reverse of `releaseTimeToReleaseTag()`
func releaseTagToReleaseTime(releaseTag string) (releaseTime time.Time, err error) {
	fields := strings.Split(releaseTag, ".")
	if len(fields) < 2 || len(fields) > 4 {