code.dwrz.net

literal_tokens.go (6316B)

---

 package ini
 
 import (
 	"fmt"
 	"strconv"
 	"strings"
 	"unicode"
 )
 
 var (
 	runesTrue  = []rune("true")
 	runesFalse = []rune("false")
 )
 
 var literalValues = [][]rune{
 	runesTrue,
 	runesFalse,
 }
 
 func isBoolValue(b []rune) bool {
 	for _, lv := range literalValues {
 		if isCaselessLitValue(lv, b) {
 			return true
 		}
 	}
 	return false
 }
 
 func isLitValue(want, have []rune) bool {
 	if len(have) < len(want) {
 		return false
 	}
 
 	for i := 0; i < len(want); i++ {
 		if want[i] != have[i] {
 			return false
 		}
 	}
 
 	return true
 }
 
 // isCaselessLitValue is a caseless value comparison, assumes want is already lower-cased for efficiency.
 func isCaselessLitValue(want, have []rune) bool {
 	if len(have) < len(want) {
 		return false
 	}
 
 	for i := 0; i < len(want); i++ {
 		if want[i] != unicode.ToLower(have[i]) {
 			return false
 		}
 	}
 
 	return true
 }
 
 // isNumberValue will return whether not the leading characters in
 // a byte slice is a number. A number is delimited by whitespace or
 // the newline token.
 //
 // A number is defined to be in a binary, octal, decimal (int | float), hex format,
 // or in scientific notation.
 func isNumberValue(b []rune) bool {
 	negativeIndex := 0
 	helper := numberHelper{}
 	needDigit := false
 
 	for i := 0; i < len(b); i++ {
 		negativeIndex++
 
 		switch b[i] {
 		case '-':
 			if helper.IsNegative() || negativeIndex != 1 {
 				return false
 			}
 			helper.Determine(b[i])
 			needDigit = true
 			continue
 		case 'e', 'E':
 			if err := helper.Determine(b[i]); err != nil {
 				return false
 			}
 			negativeIndex = 0
 			needDigit = true
 			continue
 		case 'b':
 			if helper.numberFormat == hex {
 				break
 			}
 			fallthrough
 		case 'o', 'x':
 			needDigit = true
 			if i == 0 {
 				return false
 			}
 
 			fallthrough
 		case '.':
 			if err := helper.Determine(b[i]); err != nil {
 				return false
 			}
 			needDigit = true
 			continue
 		}
 
 		if i > 0 && (isNewline(b[i:]) || isWhitespace(b[i])) {
 			return !needDigit
 		}
 
 		if !helper.CorrectByte(b[i]) {
 			return false
 		}
 		needDigit = false
 	}
 
 	return !needDigit
 }
 
 func isValid(b []rune) (bool, int, error) {
 	if len(b) == 0 {
 		// TODO: should probably return an error
 		return false, 0, nil
 	}
 
 	return isValidRune(b[0]), 1, nil
 }
 
 func isValidRune(r rune) bool {
 	return r != ':' && r != '=' && r != '[' && r != ']' && r != ' ' && r != '\n'
 }
 
 // ValueType is an enum that will signify what type
 // the Value is
 type ValueType int
 
 func (v ValueType) String() string {
 	switch v {
 	case NoneType:
 		return "NONE"
 	case DecimalType:
 		return "FLOAT"
 	case IntegerType:
 		return "INT"
 	case StringType:
 		return "STRING"
 	case BoolType:
 		return "BOOL"
 	}
 
 	return ""
 }
 
 // ValueType enums
 const (
 	NoneType = ValueType(iota)
 	DecimalType
 	IntegerType
 	StringType
 	QuotedStringType
 	BoolType
 )
 
 // Value is a union container
 type Value struct {
 	Type ValueType
 	raw  []rune
 
 	integer int64
 	decimal float64
 	boolean bool
 	str     string
 }
 
 func newValue(t ValueType, base int, raw []rune) (Value, error) {
 	v := Value{
 		Type: t,
 		raw:  raw,
 	}
 	var err error
 
 	switch t {
 	case DecimalType:
 		v.decimal, err = strconv.ParseFloat(string(raw), 64)
 	case IntegerType:
 		if base != 10 {
 			raw = raw[2:]
 		}
 
 		v.integer, err = strconv.ParseInt(string(raw), base, 64)
 	case StringType:
 		v.str = string(raw)
 	case QuotedStringType:
 		v.str = string(raw[1 : len(raw)-1])
 	case BoolType:
 		v.boolean = isCaselessLitValue(runesTrue, v.raw)
 	}
 
 	// issue 2253
 	//
 	// if the value trying to be parsed is too large, then we will use
 	// the 'StringType' and raw value instead.
 	if nerr, ok := err.(*strconv.NumError); ok && nerr.Err == strconv.ErrRange {
 		v.Type = StringType
 		v.str = string(raw)
 		err = nil
 	}
 
 	return v, err
 }
 
 // NewStringValue returns a Value type generated using a string input.
 func NewStringValue(str string) (Value, error) {
 	return newValue(StringType, 10, []rune(str))
 }
 
 // NewIntValue returns a Value type generated using an int64 input.
 func NewIntValue(i int64) (Value, error) {
 	v := strconv.FormatInt(i, 10)
 	return newValue(IntegerType, 10, []rune(v))
 }
 
 func (v Value) String() string {
 	switch v.Type {
 	case DecimalType:
 		return fmt.Sprintf("decimal: %f", v.decimal)
 	case IntegerType:
 		return fmt.Sprintf("integer: %d", v.integer)
 	case StringType:
 		return fmt.Sprintf("string: %s", string(v.raw))
 	case QuotedStringType:
 		return fmt.Sprintf("quoted string: %s", string(v.raw))
 	case BoolType:
 		return fmt.Sprintf("bool: %t", v.boolean)
 	default:
 		return "union not set"
 	}
 }
 
 func newLitToken(b []rune) (Token, int, error) {
 	n := 0
 	var err error
 
 	token := Token{}
 	if b[0] == '"' {
 		n, err = getStringValue(b)
 		if err != nil {
 			return token, n, err
 		}
 
 		token = newToken(TokenLit, b[:n], QuotedStringType)
 	} else if isNumberValue(b) {
 		var base int
 		base, n, err = getNumericalValue(b)
 		if err != nil {
 			return token, 0, err
 		}
 
 		value := b[:n]
 		vType := IntegerType
 		if contains(value, '.') || hasExponent(value) {
 			vType = DecimalType
 		}
 		token = newToken(TokenLit, value, vType)
 		token.base = base
 	} else if isBoolValue(b) {
 		n, err = getBoolValue(b)
 
 		token = newToken(TokenLit, b[:n], BoolType)
 	} else {
 		n, err = getValue(b)
 		token = newToken(TokenLit, b[:n], StringType)
 	}
 
 	return token, n, err
 }
 
 // IntValue returns an integer value
 func (v Value) IntValue() int64 {
 	return v.integer
 }
 
 // FloatValue returns a float value
 func (v Value) FloatValue() float64 {
 	return v.decimal
 }
 
 // BoolValue returns a bool value
 func (v Value) BoolValue() bool {
 	return v.boolean
 }
 
 func isTrimmable(r rune) bool {
 	switch r {
 	case '\n', ' ':
 		return true
 	}
 	return false
 }
 
 // StringValue returns the string value
 func (v Value) StringValue() string {
 	switch v.Type {
 	case StringType:
 		return strings.TrimFunc(string(v.raw), isTrimmable)
 	case QuotedStringType:
 		// preserve all characters in the quotes
 		return string(removeEscapedCharacters(v.raw[1 : len(v.raw)-1]))
 	default:
 		return strings.TrimFunc(string(v.raw), isTrimmable)
 	}
 }
 
 func contains(runes []rune, c rune) bool {
 	for i := 0; i < len(runes); i++ {
 		if runes[i] == c {
 			return true
 		}
 	}
 
 	return false
 }
 
 func runeCompare(v1 []rune, v2 []rune) bool {
 	if len(v1) != len(v2) {
 		return false
 	}
 
 	for i := 0; i < len(v1); i++ {
 		if v1[i] != v2[i] {
 			return false
 		}
 	}
 
 	return true
 }