Support numbers

parser.go

@@ -3,8 +3,11 @@ package toml
 import (
 	"bytes"
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"math"
+	"strconv"
+	"strings"
 )
 
 type builder interface {
@@ -23,6 +26,7 @@ type builder interface {
 	StringValue(v []byte)
 	BoolValue(b bool)
 	FloatValue(n float64)
+	IntValue(n int64)
 }
 
 type parser struct {
@@ -605,11 +609,11 @@ func (p parser) parseIntOrFloatOrDateTime(b []byte) ([]byte, error) {
 		p.builder.FloatValue(math.NaN())
 		return b[3:], nil
 	case '+', '-':
-		return parseIntOrFloat(b)
+		return p.parseIntOrFloat(b)
 	}
 
 	if len(b) < 3 {
-		return parseIntOrFloat(b)
+		return p.parseIntOrFloat(b)
 	}
 	for idx, c := range b[:5] {
 		if c >= '0' && c <= '9' {
@@ -622,48 +626,58 @@ func (p parser) parseIntOrFloatOrDateTime(b []byte) ([]byte, error) {
 			return parseDateTime(b)
 		}
 	}
-	return parseIntOrFloat(b)
+	return p.parseIntOrFloat(b)
 }
 
 func parseDateTime(b []byte) ([]byte, error) {
-
+	panic("implement me")
 }
 
 func (p parser) parseIntOrFloat(b []byte) ([]byte, error) {
+	i := 0
 	r := b[0]
 	if r == '0' {
 		if len(b) >= 2 {
 			var isValidRune validRuneFn
+			var parseFn func([]byte) (int64, error)
 			switch b[1] {
 			case 'x':
 				isValidRune = isValidHexRune
+				parseFn = parseIntHex
 			case 'o':
 				isValidRune = isValidOctalRune
+				parseFn = parseIntOct
 			case 'b':
 				isValidRune = isValidBinaryRune
+				parseFn = parseIntBin
 			default:
 				if b[1] >= 'a' && b[1] <= 'z' || b[1] >= 'A' && b[1] <= 'Z' {
 					return nil, fmt.Errorf("unknown number base: %s. possible options are x (hex) o (octal) b (binary)", string(b[1]))
 				}
+				parseFn = parseIntDec
 			}
 
 			if isValidRune != nil {
-				b = b[2:]
+				i = 2
 				digitSeen := false
 				for {
-					if !isValidRune(b[0]) {
+					if !isValidRune(b[i]) {
 						break
 					}
 					digitSeen = true
-					b = b[1:]
+					i++
 				}
 
 				if !digitSeen {
 					return nil, fmt.Errorf("number needs at least one digit")
 				}
 
-				p.builder.IntValue()
-				return b, nil
+				v, err := parseFn(b[:i])
+				if err != nil {
+					return nil, err
+				}
+				p.builder.IntValue(v)
+				return b[i:], nil
 			}
 		}
 	}
@@ -687,31 +701,31 @@ func (p parser) parseIntOrFloat(b []byte) ([]byte, error) {
 	pointSeen := false
 	expSeen := false
 	digitSeen := false
-	for len(b) > 0 {
-		next := b[0]
+	for i < len(b) {
+		next := b[i]
 		if next == '.' {
 			if pointSeen {
 				return nil, fmt.Errorf("cannot have two dots in one float")
 			}
-			b = b[1:]
-			if len(b) > 0 && !isDigit(b[0]) {
+			i++
+			if i < len(b) && !isDigit(b[i]) {
 				return nil, fmt.Errorf("float cannot end with a dot")
 			}
 			pointSeen = true
 		} else if next == 'e' || next == 'E' {
 			expSeen = true
-			b = b[1:]
-			if len(b) == 0 {
+			i++
+			if i >= len(b) {
 				break
 			}
-			if b[0] == '+' || b[0] == '-' {
-				b = b[1:]
+			if b[i] == '+' || b[i] == '-' {
+				i++
 			}
 		} else if isDigit(next) {
 			digitSeen = true
-			b = b[1:]
+			i++
 		} else if next == '_' {
-			b = b[1:]
+			i++
 		} else {
 			break
 		}
@@ -724,17 +738,117 @@ func (p parser) parseIntOrFloat(b []byte) ([]byte, error) {
 		return nil, fmt.Errorf("no digit in that number")
 	}
 	if pointSeen || expSeen {
-		p.builder.FloatValue()
+		f, err := parseFloat(b[:i])
+		if err != nil {
+			return nil, err
+		}
+		p.builder.FloatValue(f)
 	} else {
-		p.builder.IntValue()
+		v, err := parseIntDec(b[:i])
+		if err != nil {
+			return nil, err
+		}
+		p.builder.IntValue(v)
 	}
-	return b, nil
+	return b[i:], nil
+}
+
+func parseFloat(b []byte) (float64, error) {
+	// TODO: inefficient
+	tok := string(b)
+	err := numberContainsInvalidUnderscore(tok)
+	if err != nil {
+		return 0, err
+	}
+	cleanedVal := cleanupNumberToken(tok)
+	return strconv.ParseFloat(cleanedVal, 64)
+}
+
+func parseIntHex(b []byte) (int64, error) {
+	tok := string(b)
+	cleanedVal := cleanupNumberToken(tok)
+	err := hexNumberContainsInvalidUnderscore(cleanedVal)
+	if err != nil {
+		return 0, nil
+	}
+	return strconv.ParseInt(cleanedVal[2:], 16, 64)
+}
+
+func parseIntOct(b []byte) (int64, error) {
+	tok := string(b)
+	cleanedVal := cleanupNumberToken(tok)
+	err := numberContainsInvalidUnderscore(cleanedVal)
+	if err != nil {
+		return 0, err
+	}
+	return strconv.ParseInt(cleanedVal[2:], 8, 64)
+}
+
+func parseIntBin(b []byte) (int64, error) {
+	tok := string(b)
+	cleanedVal := cleanupNumberToken(tok)
+	err := numberContainsInvalidUnderscore(cleanedVal)
+	if err != nil {
+		return 0, err
+	}
+	return strconv.ParseInt(cleanedVal[2:], 2, 64)
+}
+
+func parseIntDec(b []byte) (int64, error) {
+	tok := string(b)
+	cleanedVal := cleanupNumberToken(tok)
+	err := numberContainsInvalidUnderscore(cleanedVal)
+	if err != nil {
+		return 0, err
+	}
+	return strconv.ParseInt(cleanedVal, 10, 64)
+}
+
+func numberContainsInvalidUnderscore(value string) error {
+	// For large numbers, you may use underscores between digits to enhance
+	// readability. Each underscore must be surrounded by at least one digit on
+	// each side.
+
+	hasBefore := false
+	for idx, r := range value {
+		if r == '_' {
+			if !hasBefore || idx+1 >= len(value) {
+				// can't end with an underscore
+				return errInvalidUnderscore
+			}
+		}
+		hasBefore = isDigitRune(r)
+	}
+	return nil
+}
+
+func hexNumberContainsInvalidUnderscore(value string) error {
+	hasBefore := false
+	for idx, r := range value {
+		if r == '_' {
+			if !hasBefore || idx+1 >= len(value) {
+				// can't end with an underscore
+				return errInvalidUnderscoreHex
+			}
+		}
+		hasBefore = isHexDigit(r)
+	}
+	return nil
+}
+
+func cleanupNumberToken(value string) string {
+	cleanedVal := strings.Replace(value, "_", "", -1)
+	return cleanedVal
 }
 
 func isDigit(r byte) bool {
 	return r >= '0' && r <= '9'
 }
 
+func isDigitRune(r rune) bool {
+	return r >= '0' && r <= '9'
+}
+
 var plusInf = math.Inf(1)
 var minusInf = math.Inf(-1)
 var nan = math.NaN()
@@ -748,6 +862,12 @@ func isValidHexRune(r byte) bool {
 		r == '_'
 }
 
+func isHexDigit(r rune) bool {
+	return isDigitRune(r) ||
+		(r >= 'a' && r <= 'f') ||
+		(r >= 'A' && r <= 'F')
+}
+
 func isValidOctalRune(r byte) bool {
 	return r >= '0' && r <= '7' || r == '_'
 }
@@ -775,3 +895,6 @@ func (u unexpectedCharacter) Error() string {
 	}
 	return fmt.Sprintf("expected %#U, not %#U", u.r, u.b[0])
 }
+
+var errInvalidUnderscore = errors.New("invalid use of _ in number")
+var errInvalidUnderscoreHex = errors.New("invalid use of _ in hex number")