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path: root/vendor/github.com/BurntSushi/toml/lex.go
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-rw-r--r--vendor/github.com/BurntSushi/toml/lex.go858
1 files changed, 0 insertions, 858 deletions
diff --git a/vendor/github.com/BurntSushi/toml/lex.go b/vendor/github.com/BurntSushi/toml/lex.go
deleted file mode 100644
index 104ebda..0000000
--- a/vendor/github.com/BurntSushi/toml/lex.go
+++ /dev/null
@@ -1,858 +0,0 @@
-package toml
-
-import (
- "fmt"
- "strings"
- "unicode"
- "unicode/utf8"
-)
-
-type itemType int
-
-const (
- itemError itemType = iota
- itemNIL // used in the parser to indicate no type
- itemEOF
- itemText
- itemString
- itemRawString
- itemMultilineString
- itemRawMultilineString
- itemBool
- itemInteger
- itemFloat
- itemDatetime
- itemArray // the start of an array
- itemArrayEnd
- itemTableStart
- itemTableEnd
- itemArrayTableStart
- itemArrayTableEnd
- itemKeyStart
- itemCommentStart
-)
-
-const (
- eof = 0
- tableStart = '['
- tableEnd = ']'
- arrayTableStart = '['
- arrayTableEnd = ']'
- tableSep = '.'
- keySep = '='
- arrayStart = '['
- arrayEnd = ']'
- arrayValTerm = ','
- commentStart = '#'
- stringStart = '"'
- stringEnd = '"'
- rawStringStart = '\''
- rawStringEnd = '\''
-)
-
-type stateFn func(lx *lexer) stateFn
-
-type lexer struct {
- input string
- start int
- pos int
- width int
- line int
- state stateFn
- items chan item
-
- // A stack of state functions used to maintain context.
- // The idea is to reuse parts of the state machine in various places.
- // For example, values can appear at the top level or within arbitrarily
- // nested arrays. The last state on the stack is used after a value has
- // been lexed. Similarly for comments.
- stack []stateFn
-}
-
-type item struct {
- typ itemType
- val string
- line int
-}
-
-func (lx *lexer) nextItem() item {
- for {
- select {
- case item := <-lx.items:
- return item
- default:
- lx.state = lx.state(lx)
- }
- }
-}
-
-func lex(input string) *lexer {
- lx := &lexer{
- input: input + "\n",
- state: lexTop,
- line: 1,
- items: make(chan item, 10),
- stack: make([]stateFn, 0, 10),
- }
- return lx
-}
-
-func (lx *lexer) push(state stateFn) {
- lx.stack = append(lx.stack, state)
-}
-
-func (lx *lexer) pop() stateFn {
- if len(lx.stack) == 0 {
- return lx.errorf("BUG in lexer: no states to pop.")
- }
- last := lx.stack[len(lx.stack)-1]
- lx.stack = lx.stack[0 : len(lx.stack)-1]
- return last
-}
-
-func (lx *lexer) current() string {
- return lx.input[lx.start:lx.pos]
-}
-
-func (lx *lexer) emit(typ itemType) {
- lx.items <- item{typ, lx.current(), lx.line}
- lx.start = lx.pos
-}
-
-func (lx *lexer) emitTrim(typ itemType) {
- lx.items <- item{typ, strings.TrimSpace(lx.current()), lx.line}
- lx.start = lx.pos
-}
-
-func (lx *lexer) next() (r rune) {
- if lx.pos >= len(lx.input) {
- lx.width = 0
- return eof
- }
-
- if lx.input[lx.pos] == '\n' {
- lx.line++
- }
- r, lx.width = utf8.DecodeRuneInString(lx.input[lx.pos:])
- lx.pos += lx.width
- return r
-}
-
-// ignore skips over the pending input before this point.
-func (lx *lexer) ignore() {
- lx.start = lx.pos
-}
-
-// backup steps back one rune. Can be called only once per call of next.
-func (lx *lexer) backup() {
- lx.pos -= lx.width
- if lx.pos < len(lx.input) && lx.input[lx.pos] == '\n' {
- lx.line--
- }
-}
-
-// accept consumes the next rune if it's equal to `valid`.
-func (lx *lexer) accept(valid rune) bool {
- if lx.next() == valid {
- return true
- }
- lx.backup()
- return false
-}
-
-// peek returns but does not consume the next rune in the input.
-func (lx *lexer) peek() rune {
- r := lx.next()
- lx.backup()
- return r
-}
-
-// skip ignores all input that matches the given predicate.
-func (lx *lexer) skip(pred func(rune) bool) {
- for {
- r := lx.next()
- if pred(r) {
- continue
- }
- lx.backup()
- lx.ignore()
- return
- }
-}
-
-// errorf stops all lexing by emitting an error and returning `nil`.
-// Note that any value that is a character is escaped if it's a special
-// character (new lines, tabs, etc.).
-func (lx *lexer) errorf(format string, values ...interface{}) stateFn {
- lx.items <- item{
- itemError,
- fmt.Sprintf(format, values...),
- lx.line,
- }
- return nil
-}
-
-// lexTop consumes elements at the top level of TOML data.
-func lexTop(lx *lexer) stateFn {
- r := lx.next()
- if isWhitespace(r) || isNL(r) {
- return lexSkip(lx, lexTop)
- }
-
- switch r {
- case commentStart:
- lx.push(lexTop)
- return lexCommentStart
- case tableStart:
- return lexTableStart
- case eof:
- if lx.pos > lx.start {
- return lx.errorf("Unexpected EOF.")
- }
- lx.emit(itemEOF)
- return nil
- }
-
- // At this point, the only valid item can be a key, so we back up
- // and let the key lexer do the rest.
- lx.backup()
- lx.push(lexTopEnd)
- return lexKeyStart
-}
-
-// lexTopEnd is entered whenever a top-level item has been consumed. (A value
-// or a table.) It must see only whitespace, and will turn back to lexTop
-// upon a new line. If it sees EOF, it will quit the lexer successfully.
-func lexTopEnd(lx *lexer) stateFn {
- r := lx.next()
- switch {
- case r == commentStart:
- // a comment will read to a new line for us.
- lx.push(lexTop)
- return lexCommentStart
- case isWhitespace(r):
- return lexTopEnd
- case isNL(r):
- lx.ignore()
- return lexTop
- case r == eof:
- lx.ignore()
- return lexTop
- }
- return lx.errorf("Expected a top-level item to end with a new line, "+
- "comment or EOF, but got %q instead.", r)
-}
-
-// lexTable lexes the beginning of a table. Namely, it makes sure that
-// it starts with a character other than '.' and ']'.
-// It assumes that '[' has already been consumed.
-// It also handles the case that this is an item in an array of tables.
-// e.g., '[[name]]'.
-func lexTableStart(lx *lexer) stateFn {
- if lx.peek() == arrayTableStart {
- lx.next()
- lx.emit(itemArrayTableStart)
- lx.push(lexArrayTableEnd)
- } else {
- lx.emit(itemTableStart)
- lx.push(lexTableEnd)
- }
- return lexTableNameStart
-}
-
-func lexTableEnd(lx *lexer) stateFn {
- lx.emit(itemTableEnd)
- return lexTopEnd
-}
-
-func lexArrayTableEnd(lx *lexer) stateFn {
- if r := lx.next(); r != arrayTableEnd {
- return lx.errorf("Expected end of table array name delimiter %q, "+
- "but got %q instead.", arrayTableEnd, r)
- }
- lx.emit(itemArrayTableEnd)
- return lexTopEnd
-}
-
-func lexTableNameStart(lx *lexer) stateFn {
- lx.skip(isWhitespace)
- switch r := lx.peek(); {
- case r == tableEnd || r == eof:
- return lx.errorf("Unexpected end of table name. (Table names cannot " +
- "be empty.)")
- case r == tableSep:
- return lx.errorf("Unexpected table separator. (Table names cannot " +
- "be empty.)")
- case r == stringStart || r == rawStringStart:
- lx.ignore()
- lx.push(lexTableNameEnd)
- return lexValue // reuse string lexing
- default:
- return lexBareTableName
- }
-}
-
-// lexBareTableName lexes the name of a table. It assumes that at least one
-// valid character for the table has already been read.
-func lexBareTableName(lx *lexer) stateFn {
- r := lx.next()
- if isBareKeyChar(r) {
- return lexBareTableName
- }
- lx.backup()
- lx.emit(itemText)
- return lexTableNameEnd
-}
-
-// lexTableNameEnd reads the end of a piece of a table name, optionally
-// consuming whitespace.
-func lexTableNameEnd(lx *lexer) stateFn {
- lx.skip(isWhitespace)
- switch r := lx.next(); {
- case isWhitespace(r):
- return lexTableNameEnd
- case r == tableSep:
- lx.ignore()
- return lexTableNameStart
- case r == tableEnd:
- return lx.pop()
- default:
- return lx.errorf("Expected '.' or ']' to end table name, but got %q "+
- "instead.", r)
- }
-}
-
-// lexKeyStart consumes a key name up until the first non-whitespace character.
-// lexKeyStart will ignore whitespace.
-func lexKeyStart(lx *lexer) stateFn {
- r := lx.peek()
- switch {
- case r == keySep:
- return lx.errorf("Unexpected key separator %q.", keySep)
- case isWhitespace(r) || isNL(r):
- lx.next()
- return lexSkip(lx, lexKeyStart)
- case r == stringStart || r == rawStringStart:
- lx.ignore()
- lx.emit(itemKeyStart)
- lx.push(lexKeyEnd)
- return lexValue // reuse string lexing
- default:
- lx.ignore()
- lx.emit(itemKeyStart)
- return lexBareKey
- }
-}
-
-// lexBareKey consumes the text of a bare key. Assumes that the first character
-// (which is not whitespace) has not yet been consumed.
-func lexBareKey(lx *lexer) stateFn {
- switch r := lx.next(); {
- case isBareKeyChar(r):
- return lexBareKey
- case isWhitespace(r):
- lx.backup()
- lx.emit(itemText)
- return lexKeyEnd
- case r == keySep:
- lx.backup()
- lx.emit(itemText)
- return lexKeyEnd
- default:
- return lx.errorf("Bare keys cannot contain %q.", r)
- }
-}
-
-// lexKeyEnd consumes the end of a key and trims whitespace (up to the key
-// separator).
-func lexKeyEnd(lx *lexer) stateFn {
- switch r := lx.next(); {
- case r == keySep:
- return lexSkip(lx, lexValue)
- case isWhitespace(r):
- return lexSkip(lx, lexKeyEnd)
- default:
- return lx.errorf("Expected key separator %q, but got %q instead.",
- keySep, r)
- }
-}
-
-// lexValue starts the consumption of a value anywhere a value is expected.
-// lexValue will ignore whitespace.
-// After a value is lexed, the last state on the next is popped and returned.
-func lexValue(lx *lexer) stateFn {
- // We allow whitespace to precede a value, but NOT new lines.
- // In array syntax, the array states are responsible for ignoring new
- // lines.
- r := lx.next()
- switch {
- case isWhitespace(r):
- return lexSkip(lx, lexValue)
- case isDigit(r):
- lx.backup() // avoid an extra state and use the same as above
- return lexNumberOrDateStart
- }
- switch r {
- case arrayStart:
- lx.ignore()
- lx.emit(itemArray)
- return lexArrayValue
- case stringStart:
- if lx.accept(stringStart) {
- if lx.accept(stringStart) {
- lx.ignore() // Ignore """
- return lexMultilineString
- }
- lx.backup()
- }
- lx.ignore() // ignore the '"'
- return lexString
- case rawStringStart:
- if lx.accept(rawStringStart) {
- if lx.accept(rawStringStart) {
- lx.ignore() // Ignore """
- return lexMultilineRawString
- }
- lx.backup()
- }
- lx.ignore() // ignore the "'"
- return lexRawString
- case '+', '-':
- return lexNumberStart
- case '.': // special error case, be kind to users
- return lx.errorf("Floats must start with a digit, not '.'.")
- }
- if unicode.IsLetter(r) {
- // Be permissive here; lexBool will give a nice error if the
- // user wrote something like
- // x = foo
- // (i.e. not 'true' or 'false' but is something else word-like.)
- lx.backup()
- return lexBool
- }
- return lx.errorf("Expected value but found %q instead.", r)
-}
-
-// lexArrayValue consumes one value in an array. It assumes that '[' or ','
-// have already been consumed. All whitespace and new lines are ignored.
-func lexArrayValue(lx *lexer) stateFn {
- r := lx.next()
- switch {
- case isWhitespace(r) || isNL(r):
- return lexSkip(lx, lexArrayValue)
- case r == commentStart:
- lx.push(lexArrayValue)
- return lexCommentStart
- case r == arrayValTerm:
- return lx.errorf("Unexpected array value terminator %q.",
- arrayValTerm)
- case r == arrayEnd:
- return lexArrayEnd
- }
-
- lx.backup()
- lx.push(lexArrayValueEnd)
- return lexValue
-}
-
-// lexArrayValueEnd consumes the cruft between values of an array. Namely,
-// it ignores whitespace and expects either a ',' or a ']'.
-func lexArrayValueEnd(lx *lexer) stateFn {
- r := lx.next()
- switch {
- case isWhitespace(r) || isNL(r):
- return lexSkip(lx, lexArrayValueEnd)
- case r == commentStart:
- lx.push(lexArrayValueEnd)
- return lexCommentStart
- case r == arrayValTerm:
- lx.ignore()
- return lexArrayValue // move on to the next value
- case r == arrayEnd:
- return lexArrayEnd
- }
- return lx.errorf("Expected an array value terminator %q or an array "+
- "terminator %q, but got %q instead.", arrayValTerm, arrayEnd, r)
-}
-
-// lexArrayEnd finishes the lexing of an array. It assumes that a ']' has
-// just been consumed.
-func lexArrayEnd(lx *lexer) stateFn {
- lx.ignore()
- lx.emit(itemArrayEnd)
- return lx.pop()
-}
-
-// lexString consumes the inner contents of a string. It assumes that the
-// beginning '"' has already been consumed and ignored.
-func lexString(lx *lexer) stateFn {
- r := lx.next()
- switch {
- case isNL(r):
- return lx.errorf("Strings cannot contain new lines.")
- case r == '\\':
- lx.push(lexString)
- return lexStringEscape
- case r == stringEnd:
- lx.backup()
- lx.emit(itemString)
- lx.next()
- lx.ignore()
- return lx.pop()
- }
- return lexString
-}
-
-// lexMultilineString consumes the inner contents of a string. It assumes that
-// the beginning '"""' has already been consumed and ignored.
-func lexMultilineString(lx *lexer) stateFn {
- r := lx.next()
- switch {
- case r == '\\':
- return lexMultilineStringEscape
- case r == stringEnd:
- if lx.accept(stringEnd) {
- if lx.accept(stringEnd) {
- lx.backup()
- lx.backup()
- lx.backup()
- lx.emit(itemMultilineString)
- lx.next()
- lx.next()
- lx.next()
- lx.ignore()
- return lx.pop()
- }
- lx.backup()
- }
- }
- return lexMultilineString
-}
-
-// lexRawString consumes a raw string. Nothing can be escaped in such a string.
-// It assumes that the beginning "'" has already been consumed and ignored.
-func lexRawString(lx *lexer) stateFn {
- r := lx.next()
- switch {
- case isNL(r):
- return lx.errorf("Strings cannot contain new lines.")
- case r == rawStringEnd:
- lx.backup()
- lx.emit(itemRawString)
- lx.next()
- lx.ignore()
- return lx.pop()
- }
- return lexRawString
-}
-
-// lexMultilineRawString consumes a raw string. Nothing can be escaped in such
-// a string. It assumes that the beginning "'" has already been consumed and
-// ignored.
-func lexMultilineRawString(lx *lexer) stateFn {
- r := lx.next()
- switch {
- case r == rawStringEnd:
- if lx.accept(rawStringEnd) {
- if lx.accept(rawStringEnd) {
- lx.backup()
- lx.backup()
- lx.backup()
- lx.emit(itemRawMultilineString)
- lx.next()
- lx.next()
- lx.next()
- lx.ignore()
- return lx.pop()
- }
- lx.backup()
- }
- }
- return lexMultilineRawString
-}
-
-// lexMultilineStringEscape consumes an escaped character. It assumes that the
-// preceding '\\' has already been consumed.
-func lexMultilineStringEscape(lx *lexer) stateFn {
- // Handle the special case first:
- if isNL(lx.next()) {
- return lexMultilineString
- }
- lx.backup()
- lx.push(lexMultilineString)
- return lexStringEscape(lx)
-}
-
-func lexStringEscape(lx *lexer) stateFn {
- r := lx.next()
- switch r {
- case 'b':
- fallthrough
- case 't':
- fallthrough
- case 'n':
- fallthrough
- case 'f':
- fallthrough
- case 'r':
- fallthrough
- case '"':
- fallthrough
- case '\\':
- return lx.pop()
- case 'u':
- return lexShortUnicodeEscape
- case 'U':
- return lexLongUnicodeEscape
- }
- return lx.errorf("Invalid escape character %q. Only the following "+
- "escape characters are allowed: "+
- "\\b, \\t, \\n, \\f, \\r, \\\", \\/, \\\\, "+
- "\\uXXXX and \\UXXXXXXXX.", r)
-}
-
-func lexShortUnicodeEscape(lx *lexer) stateFn {
- var r rune
- for i := 0; i < 4; i++ {
- r = lx.next()
- if !isHexadecimal(r) {
- return lx.errorf("Expected four hexadecimal digits after '\\u', "+
- "but got '%s' instead.", lx.current())
- }
- }
- return lx.pop()
-}
-
-func lexLongUnicodeEscape(lx *lexer) stateFn {
- var r rune
- for i := 0; i < 8; i++ {
- r = lx.next()
- if !isHexadecimal(r) {
- return lx.errorf("Expected eight hexadecimal digits after '\\U', "+
- "but got '%s' instead.", lx.current())
- }
- }
- return lx.pop()
-}
-
-// lexNumberOrDateStart consumes either an integer, a float, or datetime.
-func lexNumberOrDateStart(lx *lexer) stateFn {
- r := lx.next()
- if isDigit(r) {
- return lexNumberOrDate
- }
- switch r {
- case '_':
- return lexNumber
- case 'e', 'E':
- return lexFloat
- case '.':
- return lx.errorf("Floats must start with a digit, not '.'.")
- }
- return lx.errorf("Expected a digit but got %q.", r)
-}
-
-// lexNumberOrDate consumes either an integer, float or datetime.
-func lexNumberOrDate(lx *lexer) stateFn {
- r := lx.next()
- if isDigit(r) {
- return lexNumberOrDate
- }
- switch r {
- case '-':
- return lexDatetime
- case '_':
- return lexNumber
- case '.', 'e', 'E':
- return lexFloat
- }
-
- lx.backup()
- lx.emit(itemInteger)
- return lx.pop()
-}
-
-// lexDatetime consumes a Datetime, to a first approximation.
-// The parser validates that it matches one of the accepted formats.
-func lexDatetime(lx *lexer) stateFn {
- r := lx.next()
- if isDigit(r) {
- return lexDatetime
- }
- switch r {
- case '-', 'T', ':', '.', 'Z':
- return lexDatetime
- }
-
- lx.backup()
- lx.emit(itemDatetime)
- return lx.pop()
-}
-
-// lexNumberStart consumes either an integer or a float. It assumes that a sign
-// has already been read, but that *no* digits have been consumed.
-// lexNumberStart will move to the appropriate integer or float states.
-func lexNumberStart(lx *lexer) stateFn {
- // We MUST see a digit. Even floats have to start with a digit.
- r := lx.next()
- if !isDigit(r) {
- if r == '.' {
- return lx.errorf("Floats must start with a digit, not '.'.")
- }
- return lx.errorf("Expected a digit but got %q.", r)
- }
- return lexNumber
-}
-
-// lexNumber consumes an integer or a float after seeing the first digit.
-func lexNumber(lx *lexer) stateFn {
- r := lx.next()
- if isDigit(r) {
- return lexNumber
- }
- switch r {
- case '_':
- return lexNumber
- case '.', 'e', 'E':
- return lexFloat
- }
-
- lx.backup()
- lx.emit(itemInteger)
- return lx.pop()
-}
-
-// lexFloat consumes the elements of a float. It allows any sequence of
-// float-like characters, so floats emitted by the lexer are only a first
-// approximation and must be validated by the parser.
-func lexFloat(lx *lexer) stateFn {
- r := lx.next()
- if isDigit(r) {
- return lexFloat
- }
- switch r {
- case '_', '.', '-', '+', 'e', 'E':
- return lexFloat
- }
-
- lx.backup()
- lx.emit(itemFloat)
- return lx.pop()
-}
-
-// lexBool consumes a bool string: 'true' or 'false.
-func lexBool(lx *lexer) stateFn {
- var rs []rune
- for {
- r := lx.next()
- if r == eof || isWhitespace(r) || isNL(r) {
- lx.backup()
- break
- }
- rs = append(rs, r)
- }
- s := string(rs)
- switch s {
- case "true", "false":
- lx.emit(itemBool)
- return lx.pop()
- }
- return lx.errorf("Expected value but found %q instead.", s)
-}
-
-// lexCommentStart begins the lexing of a comment. It will emit
-// itemCommentStart and consume no characters, passing control to lexComment.
-func lexCommentStart(lx *lexer) stateFn {
- lx.ignore()
- lx.emit(itemCommentStart)
- return lexComment
-}
-
-// lexComment lexes an entire comment. It assumes that '#' has been consumed.
-// It will consume *up to* the first new line character, and pass control
-// back to the last state on the stack.
-func lexComment(lx *lexer) stateFn {
- r := lx.peek()
- if isNL(r) || r == eof {
- lx.emit(itemText)
- return lx.pop()
- }
- lx.next()
- return lexComment
-}
-
-// lexSkip ignores all slurped input and moves on to the next state.
-func lexSkip(lx *lexer, nextState stateFn) stateFn {
- return func(lx *lexer) stateFn {
- lx.ignore()
- return nextState
- }
-}
-
-// isWhitespace returns true if `r` is a whitespace character according
-// to the spec.
-func isWhitespace(r rune) bool {
- return r == '\t' || r == ' '
-}
-
-func isNL(r rune) bool {
- return r == '\n' || r == '\r'
-}
-
-func isDigit(r rune) bool {
- return r >= '0' && r <= '9'
-}
-
-func isHexadecimal(r rune) bool {
- return (r >= '0' && r <= '9') ||
- (r >= 'a' && r <= 'f') ||
- (r >= 'A' && r <= 'F')
-}
-
-func isBareKeyChar(r rune) bool {
- return (r >= 'A' && r <= 'Z') ||
- (r >= 'a' && r <= 'z') ||
- (r >= '0' && r <= '9') ||
- r == '_' ||
- r == '-'
-}
-
-func (itype itemType) String() string {
- switch itype {
- case itemError:
- return "Error"
- case itemNIL:
- return "NIL"
- case itemEOF:
- return "EOF"
- case itemText:
- return "Text"
- case itemString, itemRawString, itemMultilineString, itemRawMultilineString:
- return "String"
- case itemBool:
- return "Bool"
- case itemInteger:
- return "Integer"
- case itemFloat:
- return "Float"
- case itemDatetime:
- return "DateTime"
- case itemTableStart:
- return "TableStart"
- case itemTableEnd:
- return "TableEnd"
- case itemKeyStart:
- return "KeyStart"
- case itemArray:
- return "Array"
- case itemArrayEnd:
- return "ArrayEnd"
- case itemCommentStart:
- return "CommentStart"
- }
- panic(fmt.Sprintf("BUG: Unknown type '%d'.", int(itype)))
-}
-
-func (item item) String() string {
- return fmt.Sprintf("(%s, %s)", item.typ.String(), item.val)
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-29 08:50:25 +0000