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-rw-r--r--vendor/github.com/pelletier/go-toml/lexer.go655
1 files changed, 655 insertions, 0 deletions
diff --git a/vendor/github.com/pelletier/go-toml/lexer.go b/vendor/github.com/pelletier/go-toml/lexer.go
new file mode 100644
index 0000000..eb4d999
--- /dev/null
+++ b/vendor/github.com/pelletier/go-toml/lexer.go
@@ -0,0 +1,655 @@
+// TOML lexer.
+//
+// Written using the principles developed by Rob Pike in
+// http://www.youtube.com/watch?v=HxaD_trXwRE
+
+package toml
+
+import (
+ "errors"
+ "fmt"
+ "io"
+ "regexp"
+ "strconv"
+ "strings"
+
+ "github.com/pelletier/go-buffruneio"
+)
+
+var dateRegexp *regexp.Regexp
+
+// Define state functions
+type tomlLexStateFn func() tomlLexStateFn
+
+// Define lexer
+type tomlLexer struct {
+ input *buffruneio.Reader // Textual source
+ buffer []rune // Runes composing the current token
+ tokens chan token
+ depth int
+ line int
+ col int
+ endbufferLine int
+ endbufferCol int
+}
+
+// Basic read operations on input
+
+func (l *tomlLexer) read() rune {
+ r, err := l.input.ReadRune()
+ if err != nil {
+ panic(err)
+ }
+ if r == '\n' {
+ l.endbufferLine++
+ l.endbufferCol = 1
+ } else {
+ l.endbufferCol++
+ }
+ return r
+}
+
+func (l *tomlLexer) next() rune {
+ r := l.read()
+
+ if r != eof {
+ l.buffer = append(l.buffer, r)
+ }
+ return r
+}
+
+func (l *tomlLexer) ignore() {
+ l.buffer = make([]rune, 0)
+ l.line = l.endbufferLine
+ l.col = l.endbufferCol
+}
+
+func (l *tomlLexer) skip() {
+ l.next()
+ l.ignore()
+}
+
+func (l *tomlLexer) fastForward(n int) {
+ for i := 0; i < n; i++ {
+ l.next()
+ }
+}
+
+func (l *tomlLexer) emitWithValue(t tokenType, value string) {
+ l.tokens <- token{
+ Position: Position{l.line, l.col},
+ typ: t,
+ val: value,
+ }
+ l.ignore()
+}
+
+func (l *tomlLexer) emit(t tokenType) {
+ l.emitWithValue(t, string(l.buffer))
+}
+
+func (l *tomlLexer) peek() rune {
+ r, err := l.input.ReadRune()
+ if err != nil {
+ panic(err)
+ }
+ l.input.UnreadRune()
+ return r
+}
+
+func (l *tomlLexer) follow(next string) bool {
+ for _, expectedRune := range next {
+ r, err := l.input.ReadRune()
+ defer l.input.UnreadRune()
+ if err != nil {
+ panic(err)
+ }
+ if expectedRune != r {
+ return false
+ }
+ }
+ return true
+}
+
+// Error management
+
+func (l *tomlLexer) errorf(format string, args ...interface{}) tomlLexStateFn {
+ l.tokens <- token{
+ Position: Position{l.line, l.col},
+ typ: tokenError,
+ val: fmt.Sprintf(format, args...),
+ }
+ return nil
+}
+
+// State functions
+
+func (l *tomlLexer) lexVoid() tomlLexStateFn {
+ for {
+ next := l.peek()
+ switch next {
+ case '[':
+ return l.lexKeyGroup
+ case '#':
+ return l.lexComment
+ case '=':
+ return l.lexEqual
+ case '\r':
+ fallthrough
+ case '\n':
+ l.skip()
+ continue
+ }
+
+ if isSpace(next) {
+ l.skip()
+ }
+
+ if l.depth > 0 {
+ return l.lexRvalue
+ }
+
+ if isKeyStartChar(next) {
+ return l.lexKey
+ }
+
+ if next == eof {
+ l.next()
+ break
+ }
+ }
+
+ l.emit(tokenEOF)
+ return nil
+}
+
+func (l *tomlLexer) lexRvalue() tomlLexStateFn {
+ for {
+ next := l.peek()
+ switch next {
+ case '.':
+ return l.errorf("cannot start float with a dot")
+ case '=':
+ return l.lexEqual
+ case '[':
+ l.depth++
+ return l.lexLeftBracket
+ case ']':
+ l.depth--
+ return l.lexRightBracket
+ case '{':
+ return l.lexLeftCurlyBrace
+ case '}':
+ return l.lexRightCurlyBrace
+ case '#':
+ return l.lexComment
+ case '"':
+ return l.lexString
+ case '\'':
+ return l.lexLiteralString
+ case ',':
+ return l.lexComma
+ case '\r':
+ fallthrough
+ case '\n':
+ l.skip()
+ if l.depth == 0 {
+ return l.lexVoid
+ }
+ return l.lexRvalue
+ case '_':
+ return l.errorf("cannot start number with underscore")
+ }
+
+ if l.follow("true") {
+ return l.lexTrue
+ }
+
+ if l.follow("false") {
+ return l.lexFalse
+ }
+
+ if isSpace(next) {
+ l.skip()
+ continue
+ }
+
+ if next == eof {
+ l.next()
+ break
+ }
+
+ possibleDate := string(l.input.Peek(35))
+ dateMatch := dateRegexp.FindString(possibleDate)
+ if dateMatch != "" {
+ l.fastForward(len(dateMatch))
+ return l.lexDate
+ }
+
+ if next == '+' || next == '-' || isDigit(next) {
+ return l.lexNumber
+ }
+
+ if isAlphanumeric(next) {
+ return l.lexKey
+ }
+
+ return l.errorf("no value can start with %c", next)
+ }
+
+ l.emit(tokenEOF)
+ return nil
+}
+
+func (l *tomlLexer) lexLeftCurlyBrace() tomlLexStateFn {
+ l.next()
+ l.emit(tokenLeftCurlyBrace)
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) lexRightCurlyBrace() tomlLexStateFn {
+ l.next()
+ l.emit(tokenRightCurlyBrace)
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) lexDate() tomlLexStateFn {
+ l.emit(tokenDate)
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) lexTrue() tomlLexStateFn {
+ l.fastForward(4)
+ l.emit(tokenTrue)
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) lexFalse() tomlLexStateFn {
+ l.fastForward(5)
+ l.emit(tokenFalse)
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) lexEqual() tomlLexStateFn {
+ l.next()
+ l.emit(tokenEqual)
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) lexComma() tomlLexStateFn {
+ l.next()
+ l.emit(tokenComma)
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) lexKey() tomlLexStateFn {
+ growingString := ""
+
+ for r := l.peek(); isKeyChar(r) || r == '\n' || r == '\r'; r = l.peek() {
+ if r == '"' {
+ l.next()
+ str, err := l.lexStringAsString(`"`, false, true)
+ if err != nil {
+ return l.errorf(err.Error())
+ }
+ growingString += `"` + str + `"`
+ l.next()
+ continue
+ } else if r == '\n' {
+ return l.errorf("keys cannot contain new lines")
+ } else if isSpace(r) {
+ break
+ } else if !isValidBareChar(r) {
+ return l.errorf("keys cannot contain %c character", r)
+ }
+ growingString += string(r)
+ l.next()
+ }
+ l.emitWithValue(tokenKey, growingString)
+ return l.lexVoid
+}
+
+func (l *tomlLexer) lexComment() tomlLexStateFn {
+ for next := l.peek(); next != '\n' && next != eof; next = l.peek() {
+ if next == '\r' && l.follow("\r\n") {
+ break
+ }
+ l.next()
+ }
+ l.ignore()
+ return l.lexVoid
+}
+
+func (l *tomlLexer) lexLeftBracket() tomlLexStateFn {
+ l.next()
+ l.emit(tokenLeftBracket)
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) lexLiteralStringAsString(terminator string, discardLeadingNewLine bool) (string, error) {
+ growingString := ""
+
+ if discardLeadingNewLine {
+ if l.follow("\r\n") {
+ l.skip()
+ l.skip()
+ } else if l.peek() == '\n' {
+ l.skip()
+ }
+ }
+
+ // find end of string
+ for {
+ if l.follow(terminator) {
+ return growingString, nil
+ }
+
+ next := l.peek()
+ if next == eof {
+ break
+ }
+ growingString += string(l.next())
+ }
+
+ return "", errors.New("unclosed string")
+}
+
+func (l *tomlLexer) lexLiteralString() tomlLexStateFn {
+ l.skip()
+
+ // handle special case for triple-quote
+ terminator := "'"
+ discardLeadingNewLine := false
+ if l.follow("''") {
+ l.skip()
+ l.skip()
+ terminator = "'''"
+ discardLeadingNewLine = true
+ }
+
+ str, err := l.lexLiteralStringAsString(terminator, discardLeadingNewLine)
+ if err != nil {
+ return l.errorf(err.Error())
+ }
+
+ l.emitWithValue(tokenString, str)
+ l.fastForward(len(terminator))
+ l.ignore()
+ return l.lexRvalue
+}
+
+// Lex a string and return the results as a string.
+// Terminator is the substring indicating the end of the token.
+// The resulting string does not include the terminator.
+func (l *tomlLexer) lexStringAsString(terminator string, discardLeadingNewLine, acceptNewLines bool) (string, error) {
+ growingString := ""
+
+ if discardLeadingNewLine {
+ if l.follow("\r\n") {
+ l.skip()
+ l.skip()
+ } else if l.peek() == '\n' {
+ l.skip()
+ }
+ }
+
+ for {
+ if l.follow(terminator) {
+ return growingString, nil
+ }
+
+ if l.follow("\\") {
+ l.next()
+ switch l.peek() {
+ case '\r':
+ fallthrough
+ case '\n':
+ fallthrough
+ case '\t':
+ fallthrough
+ case ' ':
+ // skip all whitespace chars following backslash
+ for strings.ContainsRune("\r\n\t ", l.peek()) {
+ l.next()
+ }
+ case '"':
+ growingString += "\""
+ l.next()
+ case 'n':
+ growingString += "\n"
+ l.next()
+ case 'b':
+ growingString += "\b"
+ l.next()
+ case 'f':
+ growingString += "\f"
+ l.next()
+ case '/':
+ growingString += "/"
+ l.next()
+ case 't':
+ growingString += "\t"
+ l.next()
+ case 'r':
+ growingString += "\r"
+ l.next()
+ case '\\':
+ growingString += "\\"
+ l.next()
+ case 'u':
+ l.next()
+ code := ""
+ for i := 0; i < 4; i++ {
+ c := l.peek()
+ if !isHexDigit(c) {
+ return "", errors.New("unfinished unicode escape")
+ }
+ l.next()
+ code = code + string(c)
+ }
+ intcode, err := strconv.ParseInt(code, 16, 32)
+ if err != nil {
+ return "", errors.New("invalid unicode escape: \\u" + code)
+ }
+ growingString += string(rune(intcode))
+ case 'U':
+ l.next()
+ code := ""
+ for i := 0; i < 8; i++ {
+ c := l.peek()
+ if !isHexDigit(c) {
+ return "", errors.New("unfinished unicode escape")
+ }
+ l.next()
+ code = code + string(c)
+ }
+ intcode, err := strconv.ParseInt(code, 16, 64)
+ if err != nil {
+ return "", errors.New("invalid unicode escape: \\U" + code)
+ }
+ growingString += string(rune(intcode))
+ default:
+ return "", errors.New("invalid escape sequence: \\" + string(l.peek()))
+ }
+ } else {
+ r := l.peek()
+
+ if 0x00 <= r && r <= 0x1F && !(acceptNewLines && (r == '\n' || r == '\r')) {
+ return "", fmt.Errorf("unescaped control character %U", r)
+ }
+ l.next()
+ growingString += string(r)
+ }
+
+ if l.peek() == eof {
+ break
+ }
+ }
+
+ return "", errors.New("unclosed string")
+}
+
+func (l *tomlLexer) lexString() tomlLexStateFn {
+ l.skip()
+
+ // handle special case for triple-quote
+ terminator := `"`
+ discardLeadingNewLine := false
+ acceptNewLines := false
+ if l.follow(`""`) {
+ l.skip()
+ l.skip()
+ terminator = `"""`
+ discardLeadingNewLine = true
+ acceptNewLines = true
+ }
+
+ str, err := l.lexStringAsString(terminator, discardLeadingNewLine, acceptNewLines)
+
+ if err != nil {
+ return l.errorf(err.Error())
+ }
+
+ l.emitWithValue(tokenString, str)
+ l.fastForward(len(terminator))
+ l.ignore()
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) lexKeyGroup() tomlLexStateFn {
+ l.next()
+
+ if l.peek() == '[' {
+ // token '[[' signifies an array of anonymous key groups
+ l.next()
+ l.emit(tokenDoubleLeftBracket)
+ return l.lexInsideKeyGroupArray
+ }
+ // vanilla key group
+ l.emit(tokenLeftBracket)
+ return l.lexInsideKeyGroup
+}
+
+func (l *tomlLexer) lexInsideKeyGroupArray() tomlLexStateFn {
+ for r := l.peek(); r != eof; r = l.peek() {
+ switch r {
+ case ']':
+ if len(l.buffer) > 0 {
+ l.emit(tokenKeyGroupArray)
+ }
+ l.next()
+ if l.peek() != ']' {
+ break
+ }
+ l.next()
+ l.emit(tokenDoubleRightBracket)
+ return l.lexVoid
+ case '[':
+ return l.errorf("group name cannot contain ']'")
+ default:
+ l.next()
+ }
+ }
+ return l.errorf("unclosed key group array")
+}
+
+func (l *tomlLexer) lexInsideKeyGroup() tomlLexStateFn {
+ for r := l.peek(); r != eof; r = l.peek() {
+ switch r {
+ case ']':
+ if len(l.buffer) > 0 {
+ l.emit(tokenKeyGroup)
+ }
+ l.next()
+ l.emit(tokenRightBracket)
+ return l.lexVoid
+ case '[':
+ return l.errorf("group name cannot contain ']'")
+ default:
+ l.next()
+ }
+ }
+ return l.errorf("unclosed key group")
+}
+
+func (l *tomlLexer) lexRightBracket() tomlLexStateFn {
+ l.next()
+ l.emit(tokenRightBracket)
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) lexNumber() tomlLexStateFn {
+ r := l.peek()
+ if r == '+' || r == '-' {
+ l.next()
+ }
+ pointSeen := false
+ expSeen := false
+ digitSeen := false
+ for {
+ next := l.peek()
+ if next == '.' {
+ if pointSeen {
+ return l.errorf("cannot have two dots in one float")
+ }
+ l.next()
+ if !isDigit(l.peek()) {
+ return l.errorf("float cannot end with a dot")
+ }
+ pointSeen = true
+ } else if next == 'e' || next == 'E' {
+ expSeen = true
+ l.next()
+ r := l.peek()
+ if r == '+' || r == '-' {
+ l.next()
+ }
+ } else if isDigit(next) {
+ digitSeen = true
+ l.next()
+ } else if next == '_' {
+ l.next()
+ } else {
+ break
+ }
+ if pointSeen && !digitSeen {
+ return l.errorf("cannot start float with a dot")
+ }
+ }
+
+ if !digitSeen {
+ return l.errorf("no digit in that number")
+ }
+ if pointSeen || expSeen {
+ l.emit(tokenFloat)
+ } else {
+ l.emit(tokenInteger)
+ }
+ return l.lexRvalue
+}
+
+func (l *tomlLexer) run() {
+ for state := l.lexVoid; state != nil; {
+ state = state()
+ }
+ close(l.tokens)
+}
+
+func init() {
+ dateRegexp = regexp.MustCompile(`^\d{1,4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(\.\d{1,9})?(Z|[+-]\d{2}:\d{2})`)
+}
+
+// Entry point
+func lexToml(input io.Reader) chan token {
+ bufferedInput := buffruneio.NewReader(input)
+ l := &tomlLexer{
+ input: bufferedInput,
+ tokens: make(chan token),
+ line: 1,
+ col: 1,
+ endbufferLine: 1,
+ endbufferCol: 1,
+ }
+ go l.run()
+ return l.tokens
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-29 14:27:27 +0000