/**
* <strong>[11.6] Identifier Names and Identifiers</strong>
*
* <pre>
* Identifier ::
* IdentifierName but not ReservedWord
* IdentifierName ::
* IdentifierStart
* IdentifierName IdentifierPart
* </pre>
*/
private Token readIdentifier(int c) {
assert isIdentifierStart(c);
TokenStreamInput input = this.input;
StringBuffer buffer = this.buffer();
buffer.addCodepoint(c);
for (; ; ) {
c = input.get();
if (isIdentifierPart(c)) {
buffer.add(c);
} else if (c == '\\') {
mustMatch('u');
c = readUnicode();
if (!isIdentifierPart(c)) {
throw error(Messages.Key.InvalidUnicodeEscapedIdentifierPart);
}
buffer.addCodepoint(c);
continue;
} else {
input.unget(c);
break;
}
}
Token tok = readReservedWord(buffer);
if (tok != null) {
return tok;
}
return Token.NAME;
}
/**
* <strong>[11.8.6] Template Literal Lexical Components</strong>
*
* <pre>
* Template ::
* NoSubstitutionTemplate
* TemplateHead
* NoSubstitutionTemplate ::
* ` TemplateCharacters<sub>opt</sub>`
* TemplateHead ::
* ` TemplateCharacters<sub>opt</sub>${
* TemplateSubstitutionTail ::
* TemplateMiddle
* TemplateTail
* TemplateMiddle ::
* } TemplateCharacters<sub>opt</sub>${
* TemplateTail ::
* } TemplateCharacters<sub>opt</sub>`
* TemplateCharacters ::
* TemplateCharacter TemplateCharacters<sub>opt</sub>
* TemplateCharacter ::
* SourceCharacter but not one of ` or \ or $
* $ [LA ∉ { ]
* \ EscapeSequence
* LineContinuation
* </pre>
*/
public String[] readTemplateLiteral(Token start) {
assert start == Token.TEMPLATE || start == Token.RC;
assert currentToken() == start;
assert next == null : "template literal in lookahead";
final int EOF = TokenStreamInput.EOF;
TokenStreamInput input = this.input;
StringBuilder raw = new StringBuilder();
StringBuffer buffer = buffer();
int pos = input.position();
for (; ; ) {
int c = input.get();
if (c == EOF) {
throw eofError(Messages.Key.UnterminatedTemplateLiteral);
}
if (c == '`') {
current = Token.TEMPLATE;
raw.append(input.range(pos, input.position() - 1));
return new String[] {buffer.toString(), raw.toString()};
}
if (c == '$' && match('{')) {
current = Token.LC;
raw.append(input.range(pos, input.position() - 2));
return new String[] {buffer.toString(), raw.toString()};
}
if (c != '\\') {
if (isLineTerminator(c)) {
// line terminator sequence
if (c == '\r') {
// normalise \r and \r\n to \n
raw.append(input.range(pos, input.position() - 1)).append('\n');
match('\n');
pos = input.position();
c = '\n';
}
buffer.add(c);
incrementLine();
continue;
}
// TODO: add substring range
buffer.add(c);
continue;
}
c = input.get();
if (c == EOF) {
throw eofError(Messages.Key.UnterminatedTemplateLiteral);
}
// EscapeSequence
if (isLineTerminator(c)) {
// line continuation
if (c == '\r') {
// normalise \r and \r\n to \n
raw.append(input.range(pos, input.position() - 1)).append('\n');
match('\n');
pos = input.position();
}
incrementLine();
continue;
}
switch (c) {
case 'b':
c = '\b';
break;
case 'f':
c = '\f';
break;
case 'n':
c = '\n';
break;
case 'r':
c = '\r';
break;
case 't':
c = '\t';
break;
case 'v':
c = '\u000B';
break;
case '0':
if (isDecimalDigit(input.peek(0))) {
throw error(Messages.Key.InvalidNULLEscape);
}
c = '\0';
break;
case 'x':
c = (hexDigit(input.get()) << 4) | hexDigit(input.get());
if (c < 0) {
throw error(Messages.Key.InvalidHexEscape);
}
break;
case 'u':
c = readUnicode();
break;
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
throw error(Messages.Key.StrictModeOctalEscapeSequence);
case '"':
case '\'':
case '\\':
default:
// fall-through
}
buffer.addCodepoint(c);
}
}
/**
* <strong>[11.8.4] String Literals</strong>
*
* <pre>
* StringLiteral ::
* " DoubleStringCharacters<sub>opt</sub> "
* ' SingleStringCharacters<sub>opt</sub> '
* DoubleStringCharacters ::
* DoubleStringCharacter DoubleStringCharacters<sub>opt</sub>
* SingleStringCharacters ::
* SingleStringCharacter SingleStringCharacters<sub>opt</sub>
* DoubleStringCharacter ::
* SourceCharacter but not one of " or \ or LineTerminator
* \ EscapeSequence
* LineContinuation
* SingleStringCharacter ::
* SourceCharacter but not one of ' or \ or LineTerminator
* \ EscapeSequence
* LineContinuation
* LineContinuation ::
* \ LineTerminatorSequence
* EscapeSequence ::
* CharacterEscapeSequence
* 0 [lookahead ∉ DecimalDigit]
* HexEscapeSequence
* UnicodeEscapeSequence
* CharacterEscapeSequence ::
* SingleEscapeCharacter
* NonEscapeCharacter
* SingleEscapeCharacter :: one of
* ' " \ b f n r t v
* NonEscapeCharacter ::
* SourceCharacter but not one of EscapeCharacter or LineTerminator
* EscapeCharacter ::
* SingleEscapeCharacter
* DecimalDigit
* x
* u
* HexEscapeSequence ::
* x HexDigit HexDigit
* UnicodeEscapeSequence ::
* u HexDigit HexDigit HexDigit HexDigit
* u{ HexDigits }
* </pre>
*
* <strong>[B.1.2] String Literals</strong>
*
* <pre>
* EscapeSequence ::
* CharacterEscapeSequence
* OctalEscapeSequence
* HexEscapeSequence
* UnicodeEscapeSequence
* </pre>
*/
private Token readString(int quoteChar) {
assert quoteChar == '"' || quoteChar == '\'';
final int EOF = TokenStreamInput.EOF;
TokenStreamInput input = this.input;
int start = input.position();
StringBuffer buffer = this.buffer();
hasEscape = false;
for (; ; ) {
int c = input.get();
if (c == EOF) {
throw eofError(Messages.Key.UnterminatedStringLiteral);
}
if (c == quoteChar) {
buffer.add(input.range(start, input.position() - 1));
break;
}
if (isLineTerminator(c)) {
throw error(Messages.Key.UnterminatedStringLiteral);
}
if (c != '\\') {
continue;
}
buffer.add(input.range(start, input.position() - 1));
hasEscape = true;
c = input.get();
if (isLineTerminator(c)) {
// line continuation
if (c == '\r' && match('\n')) {
// \r\n sequence
}
incrementLine();
start = input.position();
continue;
}
// escape sequences
switch (c) {
case 'b':
c = '\b';
break;
case 'f':
c = '\f';
break;
case 'n':
c = '\n';
break;
case 'r':
c = '\r';
break;
case 't':
c = '\t';
break;
case 'v':
c = '\u000B';
break;
case 'x':
c = (hexDigit(input.get()) << 4) | hexDigit(input.get());
if (c < 0) {
throw error(Messages.Key.InvalidHexEscape);
}
break;
case 'u':
c = readUnicode();
break;
case '0':
if (isDecimalDigit(input.peek(0))) {
if (!parser.isEnabled(CompatibilityOption.OctalEscapeSequence)) {
throw error(Messages.Key.InvalidNULLEscape);
}
c = readOctalEscape(c);
} else {
c = '\0';
}
break;
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
if (!parser.isEnabled(CompatibilityOption.OctalEscapeSequence)) {
throw error(Messages.Key.StrictModeOctalEscapeSequence);
}
c = readOctalEscape(c);
break;
case '8':
case '9':
// FIXME: spec bug - undefined behaviour for \8 and \9
if (!parser.isEnabled(CompatibilityOption.OctalEscapeSequence)) {
throw error(Messages.Key.StrictModeOctalEscapeSequence);
}
// fall-through
case '"':
case '\'':
case '\\':
default:
// fall-through
}
buffer.addCodepoint(c);
start = input.position();
}
return Token.STRING;
}