fix(go.sum): update ResolveSpec dependency to v1.0.87

vendor/github.com/segmentio/encoding/iso8601/valid.go

@@ -0,0 +1,179 @@
+package iso8601
+
+// ValidFlags is a bitset type used to configure the behavior of the Valid
+// function.
+type ValidFlags int
+
+const (
+	// Strict is a validation flag used to represent a string iso8601 validation
+	// (this is the default).
+	Strict ValidFlags = 0
+
+	// AllowSpaceSeparator allows the presence of a space instead of a 'T' as
+	// separator between the date and time.
+	AllowSpaceSeparator ValidFlags = 1 << iota
+
+	// AllowMissingTime allows the value to contain only a date.
+	AllowMissingTime
+
+	// AllowMissingSubsecond allows the value to contain only a date and time.
+	AllowMissingSubsecond
+
+	// AllowMissingTimezone allows the value to be missing the timezone
+	// information.
+	AllowMissingTimezone
+
+	// AllowNumericTimezone allows the value to represent timezones in their
+	// numeric form.
+	AllowNumericTimezone
+
+	// Flexible is a combination of all validation flag that allow for
+	// non-strict checking of the input value.
+	Flexible = AllowSpaceSeparator | AllowMissingTime | AllowMissingSubsecond | AllowMissingTimezone | AllowNumericTimezone
+)
+
+// Valid check value to verify whether or not it is a valid iso8601 time
+// representation.
+func Valid(value string, flags ValidFlags) bool {
+	var ok bool
+
+	// year
+	if value, ok = readDigits(value, 4, 4); !ok {
+		return false
+	}
+
+	if value, ok = readByte(value, '-'); !ok {
+		return false
+	}
+
+	// month
+	if value, ok = readDigits(value, 2, 2); !ok {
+		return false
+	}
+
+	if value, ok = readByte(value, '-'); !ok {
+		return false
+	}
+
+	// day
+	if value, ok = readDigits(value, 2, 2); !ok {
+		return false
+	}
+
+	if len(value) == 0 && (flags&AllowMissingTime) != 0 {
+		return true // date only
+	}
+
+	// separator
+	if value, ok = readByte(value, 'T'); !ok {
+		if (flags & AllowSpaceSeparator) == 0 {
+			return false
+		}
+		if value, ok = readByte(value, ' '); !ok {
+			return false
+		}
+	}
+
+	// hour
+	if value, ok = readDigits(value, 2, 2); !ok {
+		return false
+	}
+
+	if value, ok = readByte(value, ':'); !ok {
+		return false
+	}
+
+	// minute
+	if value, ok = readDigits(value, 2, 2); !ok {
+		return false
+	}
+
+	if value, ok = readByte(value, ':'); !ok {
+		return false
+	}
+
+	// second
+	if value, ok = readDigits(value, 2, 2); !ok {
+		return false
+	}
+
+	// microsecond
+	if value, ok = readByte(value, '.'); !ok {
+		if (flags & AllowMissingSubsecond) == 0 {
+			return false
+		}
+	} else {
+		if value, ok = readDigits(value, 1, 9); !ok {
+			return false
+		}
+	}
+
+	if len(value) == 0 && (flags&AllowMissingTimezone) != 0 {
+		return true // date and time
+	}
+
+	// timezone
+	if value, ok = readByte(value, 'Z'); ok {
+		return len(value) == 0
+	}
+
+	if (flags & AllowSpaceSeparator) != 0 {
+		value, _ = readByte(value, ' ')
+	}
+
+	if value, ok = readByte(value, '+'); !ok {
+		if value, ok = readByte(value, '-'); !ok {
+			return false
+		}
+	}
+
+	// timezone hour
+	if value, ok = readDigits(value, 2, 2); !ok {
+		return false
+	}
+
+	if value, ok = readByte(value, ':'); !ok {
+		if (flags & AllowNumericTimezone) == 0 {
+			return false
+		}
+	}
+
+	// timezone minute
+	if value, ok = readDigits(value, 2, 2); !ok {
+		return false
+	}
+
+	return len(value) == 0
+}
+
+func readDigits(value string, min, max int) (string, bool) {
+	if len(value) < min {
+		return value, false
+	}
+
+	i := 0
+
+	for i < max && i < len(value) && isDigit(value[i]) {
+		i++
+	}
+
+	if i < max && i < min {
+		return value, false
+	}
+
+	return value[i:], true
+}
+
+func readByte(value string, c byte) (string, bool) {
+	if len(value) == 0 {
+		return value, false
+	}
+	if value[0] != c {
+		return value, false
+	}
+	return value[1:], true
+}
+
+func isDigit(c byte) bool {
+	return '0' <= c && c <= '9'
+}