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-rw-r--r--vendor/github.com/vektah/gqlparser/lexer/lexer.go510
1 files changed, 510 insertions, 0 deletions
diff --git a/vendor/github.com/vektah/gqlparser/lexer/lexer.go b/vendor/github.com/vektah/gqlparser/lexer/lexer.go
new file mode 100644
index 00000000..3aaa7102
--- /dev/null
+++ b/vendor/github.com/vektah/gqlparser/lexer/lexer.go
@@ -0,0 +1,510 @@
+package lexer
+
+import (
+ "bytes"
+ "unicode/utf8"
+
+ "github.com/vektah/gqlparser/ast"
+ "github.com/vektah/gqlparser/gqlerror"
+)
+
+// Lexer turns graphql request and schema strings into tokens
+type Lexer struct {
+ *ast.Source
+ // An offset into the string in bytes
+ start int
+ // An offset into the string in runes
+ startRunes int
+ // An offset into the string in bytes
+ end int
+ // An offset into the string in runes
+ endRunes int
+ // the current line number
+ line int
+ // An offset into the string in rune
+ lineStartRunes int
+}
+
+func New(src *ast.Source) Lexer {
+ return Lexer{
+ Source: src,
+ line: 1,
+ }
+}
+
+// take one rune from input and advance end
+func (s *Lexer) peek() (rune, int) {
+ return utf8.DecodeRuneInString(s.Input[s.end:])
+}
+
+func (s *Lexer) makeToken(kind Type) (Token, *gqlerror.Error) {
+ return s.makeValueToken(kind, s.Input[s.start:s.end])
+}
+
+func (s *Lexer) makeValueToken(kind Type, value string) (Token, *gqlerror.Error) {
+ return Token{
+ Kind: kind,
+ Value: value,
+ Pos: ast.Position{
+ Start: s.startRunes,
+ End: s.endRunes,
+ Line: s.line,
+ Column: s.startRunes - s.lineStartRunes + 1,
+ Src: s.Source,
+ },
+ }, nil
+}
+
+func (s *Lexer) makeError(format string, args ...interface{}) (Token, *gqlerror.Error) {
+ column := s.endRunes - s.lineStartRunes + 1
+ return Token{
+ Kind: Invalid,
+ Pos: ast.Position{
+ Start: s.startRunes,
+ End: s.endRunes,
+ Line: s.line,
+ Column: column,
+ Src: s.Source,
+ },
+ }, gqlerror.ErrorLocf(s.Source.Name, s.line, column, format, args...)
+}
+
+// ReadToken gets the next token from the source starting at the given position.
+//
+// This skips over whitespace and comments until it finds the next lexable
+// token, then lexes punctuators immediately or calls the appropriate helper
+// function for more complicated tokens.
+func (s *Lexer) ReadToken() (token Token, err *gqlerror.Error) {
+
+ s.ws()
+ s.start = s.end
+ s.startRunes = s.endRunes
+
+ if s.end >= len(s.Input) {
+ return s.makeToken(EOF)
+ }
+ r := s.Input[s.start]
+ s.end++
+ s.endRunes++
+ switch r {
+ case '!':
+ return s.makeValueToken(Bang, "")
+
+ case '$':
+ return s.makeValueToken(Dollar, "")
+ case '&':
+ return s.makeValueToken(Amp, "")
+ case '(':
+ return s.makeValueToken(ParenL, "")
+ case ')':
+ return s.makeValueToken(ParenR, "")
+ case '.':
+ if len(s.Input) > s.start+2 && s.Input[s.start:s.start+3] == "..." {
+ s.end += 2
+ s.endRunes += 2
+ return s.makeValueToken(Spread, "")
+ }
+ case ':':
+ return s.makeValueToken(Colon, "")
+ case '=':
+ return s.makeValueToken(Equals, "")
+ case '@':
+ return s.makeValueToken(At, "")
+ case '[':
+ return s.makeValueToken(BracketL, "")
+ case ']':
+ return s.makeValueToken(BracketR, "")
+ case '{':
+ return s.makeValueToken(BraceL, "")
+ case '}':
+ return s.makeValueToken(BraceR, "")
+ case '|':
+ return s.makeValueToken(Pipe, "")
+ case '#':
+ s.readComment()
+ return s.ReadToken()
+
+ case '_', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z':
+ return s.readName()
+
+ case '-', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
+ return s.readNumber()
+
+ case '"':
+ if len(s.Input) > s.start+2 && s.Input[s.start:s.start+3] == `"""` {
+ return s.readBlockString()
+ }
+
+ return s.readString()
+ }
+
+ s.end--
+ s.endRunes--
+
+ if r < 0x0020 && r != 0x0009 && r != 0x000a && r != 0x000d {
+ return s.makeError(`Cannot contain the invalid character "\u%04d"`, r)
+ }
+
+ if r == '\'' {
+ return s.makeError(`Unexpected single quote character ('), did you mean to use a double quote (")?`)
+ }
+
+ return s.makeError(`Cannot parse the unexpected character "%s".`, string(r))
+}
+
+// ws reads from body starting at startPosition until it finds a non-whitespace
+// or commented character, and updates the token end to include all whitespace
+func (s *Lexer) ws() {
+ for s.end < len(s.Input) {
+ switch s.Input[s.end] {
+ case '\t', ' ', ',':
+ s.end++
+ s.endRunes++
+ case '\n':
+ s.end++
+ s.endRunes++
+ s.line++
+ s.lineStartRunes = s.endRunes
+ case '\r':
+ s.end++
+ s.endRunes++
+ s.line++
+ s.lineStartRunes = s.endRunes
+ // skip the following newline if its there
+ if s.end < len(s.Input) && s.Input[s.end] == '\n' {
+ s.end++
+ s.endRunes++
+ }
+ // byte order mark, given ws is hot path we aren't relying on the unicode package here.
+ case 0xef:
+ if s.end+2 < len(s.Input) && s.Input[s.end+1] == 0xBB && s.Input[s.end+2] == 0xBF {
+ s.end += 3
+ s.endRunes++
+ } else {
+ return
+ }
+ default:
+ return
+ }
+ }
+}
+
+// readComment from the input
+//
+// #[\u0009\u0020-\uFFFF]*
+func (s *Lexer) readComment() (Token, *gqlerror.Error) {
+ for s.end < len(s.Input) {
+ r, w := s.peek()
+
+ // SourceCharacter but not LineTerminator
+ if r > 0x001f || r == '\t' {
+ s.end += w
+ s.endRunes++
+ } else {
+ break
+ }
+ }
+
+ return s.makeToken(Comment)
+}
+
+// readNumber from the input, either a float
+// or an int depending on whether a decimal point appears.
+//
+// Int: -?(0|[1-9][0-9]*)
+// Float: -?(0|[1-9][0-9]*)(\.[0-9]+)?((E|e)(+|-)?[0-9]+)?
+func (s *Lexer) readNumber() (Token, *gqlerror.Error) {
+ float := false
+
+ // backup to the first digit
+ s.end--
+ s.endRunes--
+
+ s.acceptByte('-')
+
+ if s.acceptByte('0') {
+ if consumed := s.acceptDigits(); consumed != 0 {
+ s.end -= consumed
+ s.endRunes -= consumed
+ return s.makeError("Invalid number, unexpected digit after 0: %s.", s.describeNext())
+ }
+ } else {
+ if consumed := s.acceptDigits(); consumed == 0 {
+ return s.makeError("Invalid number, expected digit but got: %s.", s.describeNext())
+ }
+ }
+
+ if s.acceptByte('.') {
+ float = true
+
+ if consumed := s.acceptDigits(); consumed == 0 {
+ return s.makeError("Invalid number, expected digit but got: %s.", s.describeNext())
+ }
+ }
+
+ if s.acceptByte('e', 'E') {
+ float = true
+
+ s.acceptByte('-', '+')
+
+ if consumed := s.acceptDigits(); consumed == 0 {
+ return s.makeError("Invalid number, expected digit but got: %s.", s.describeNext())
+ }
+ }
+
+ if float {
+ return s.makeToken(Float)
+ } else {
+ return s.makeToken(Int)
+ }
+}
+
+// acceptByte if it matches any of given bytes, returning true if it found anything
+func (s *Lexer) acceptByte(bytes ...uint8) bool {
+ if s.end >= len(s.Input) {
+ return false
+ }
+
+ for _, accepted := range bytes {
+ if s.Input[s.end] == accepted {
+ s.end++
+ s.endRunes++
+ return true
+ }
+ }
+ return false
+}
+
+// acceptDigits from the input, returning the number of digits it found
+func (s *Lexer) acceptDigits() int {
+ consumed := 0
+ for s.end < len(s.Input) && s.Input[s.end] >= '0' && s.Input[s.end] <= '9' {
+ s.end++
+ s.endRunes++
+ consumed++
+ }
+
+ return consumed
+}
+
+// describeNext peeks at the input and returns a human readable string. This should will alloc
+// and should only be used in errors
+func (s *Lexer) describeNext() string {
+ if s.end < len(s.Input) {
+ return `"` + string(s.Input[s.end]) + `"`
+ }
+ return "<EOF>"
+}
+
+// readString from the input
+//
+// "([^"\\\u000A\u000D]|(\\(u[0-9a-fA-F]{4}|["\\/bfnrt])))*"
+func (s *Lexer) readString() (Token, *gqlerror.Error) {
+ inputLen := len(s.Input)
+
+ // this buffer is lazily created only if there are escape characters.
+ var buf *bytes.Buffer
+
+ // skip the opening quote
+ s.start++
+ s.startRunes++
+
+ for s.end < inputLen {
+ r := s.Input[s.end]
+ if r == '\n' || r == '\r' {
+ break
+ }
+ if r < 0x0020 && r != '\t' {
+ return s.makeError(`Invalid character within String: "\u%04d".`, r)
+ }
+ switch r {
+ default:
+ var char = rune(r)
+ var w = 1
+
+ // skip unicode overhead if we are in the ascii range
+ if r >= 127 {
+ char, w = utf8.DecodeRuneInString(s.Input[s.end:])
+ }
+ s.end += w
+ s.endRunes++
+
+ if buf != nil {
+ buf.WriteRune(char)
+ }
+
+ case '"':
+ t, err := s.makeToken(String)
+ // the token should not include the quotes in its value, but should cover them in its position
+ t.Pos.Start--
+ t.Pos.End++
+
+ if buf != nil {
+ t.Value = buf.String()
+ }
+
+ // skip the close quote
+ s.end++
+ s.endRunes++
+
+ return t, err
+
+ case '\\':
+ if s.end+1 >= inputLen {
+ s.end++
+ s.endRunes++
+ return s.makeError(`Invalid character escape sequence.`)
+ }
+
+ if buf == nil {
+ buf = bytes.NewBufferString(s.Input[s.start:s.end])
+ }
+
+ escape := s.Input[s.end+1]
+
+ if escape == 'u' {
+ if s.end+6 >= inputLen {
+ s.end++
+ s.endRunes++
+ return s.makeError("Invalid character escape sequence: \\%s.", s.Input[s.end:])
+ }
+
+ r, ok := unhex(s.Input[s.end+2 : s.end+6])
+ if !ok {
+ s.end++
+ s.endRunes++
+ return s.makeError("Invalid character escape sequence: \\%s.", s.Input[s.end:s.end+5])
+ }
+ buf.WriteRune(r)
+ s.end += 6
+ s.endRunes += 6
+ } else {
+ switch escape {
+ case '"', '/', '\\':
+ buf.WriteByte(escape)
+ case 'b':
+ buf.WriteByte('\b')
+ case 'f':
+ buf.WriteByte('\f')
+ case 'n':
+ buf.WriteByte('\n')
+ case 'r':
+ buf.WriteByte('\r')
+ case 't':
+ buf.WriteByte('\t')
+ default:
+ s.end += 1
+ s.endRunes += 1
+ return s.makeError("Invalid character escape sequence: \\%s.", string(escape))
+ }
+ s.end += 2
+ s.endRunes += 2
+ }
+ }
+ }
+
+ return s.makeError("Unterminated string.")
+}
+
+// readBlockString from the input
+//
+// """("?"?(\\"""|\\(?!=""")|[^"\\]))*"""
+func (s *Lexer) readBlockString() (Token, *gqlerror.Error) {
+ inputLen := len(s.Input)
+
+ var buf bytes.Buffer
+
+ // skip the opening quote
+ s.start += 3
+ s.startRunes += 3
+ s.end += 2
+ s.endRunes += 2
+
+ for s.end < inputLen {
+ r := s.Input[s.end]
+
+ // Closing triple quote (""")
+ if r == '"' && s.end+3 <= inputLen && s.Input[s.end:s.end+3] == `"""` {
+ t, err := s.makeValueToken(BlockString, blockStringValue(buf.String()))
+
+ // the token should not include the quotes in its value, but should cover them in its position
+ t.Pos.Start -= 3
+ t.Pos.End += 3
+
+ // skip the close quote
+ s.end += 3
+ s.endRunes += 3
+
+ return t, err
+ }
+
+ // SourceCharacter
+ if r < 0x0020 && r != '\t' && r != '\n' && r != '\r' {
+ return s.makeError(`Invalid character within String: "\u%04d".`, r)
+ }
+
+ if r == '\\' && s.end+4 <= inputLen && s.Input[s.end:s.end+4] == `\"""` {
+ buf.WriteString(`"""`)
+ s.end += 4
+ s.endRunes += 4
+ } else if r == '\r' {
+ if s.end+1 <= inputLen && s.Input[s.end+1] == '\n' {
+ s.end++
+ s.endRunes++
+ }
+
+ buf.WriteByte('\n')
+ s.end++
+ s.endRunes++
+ } else {
+ var char = rune(r)
+ var w = 1
+
+ // skip unicode overhead if we are in the ascii range
+ if r >= 127 {
+ char, w = utf8.DecodeRuneInString(s.Input[s.end:])
+ }
+ s.end += w
+ s.endRunes++
+ buf.WriteRune(char)
+ }
+ }
+
+ return s.makeError("Unterminated string.")
+}
+
+func unhex(b string) (v rune, ok bool) {
+ for _, c := range b {
+ v <<= 4
+ switch {
+ case '0' <= c && c <= '9':
+ v |= c - '0'
+ case 'a' <= c && c <= 'f':
+ v |= c - 'a' + 10
+ case 'A' <= c && c <= 'F':
+ v |= c - 'A' + 10
+ default:
+ return 0, false
+ }
+ }
+
+ return v, true
+}
+
+// readName from the input
+//
+// [_A-Za-z][_0-9A-Za-z]*
+func (s *Lexer) readName() (Token, *gqlerror.Error) {
+ for s.end < len(s.Input) {
+ r, w := s.peek()
+
+ if (r >= '0' && r <= '9') || (r >= 'A' && r <= 'Z') || (r >= 'a' && r <= 'z') || r == '_' {
+ s.end += w
+ s.endRunes++
+ } else {
+ break
+ }
+ }
+
+ return s.makeToken(Name)
+}
generated by cgit (git 2.34.1) at 2024-10-19 04:34:00 +0000