Move scanner into pkg/front_end/lib/src/scanner.

pkg/analyzer/lib/src/dart/ast/token.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.src.dart.ast.token;
 
-import 'package:analyzer/dart/ast/token.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
+import 'package:front_end/src/scanner/token.dart';
 
-/**
- * The opening half of a grouping pair of tokens. This is used for curly
- * brackets ('{'), parentheses ('('), and square brackets ('[').
- */
-class BeginToken extends SimpleToken {
-  /**
-   * The token that corresponds to this token.
-   */
-  Token endToken;
-
-  /**
-   * Initialize a newly created token to have the given [type] at the given
-   * [offset].
-   */
-  BeginToken(TokenType type, int offset) : super(type, offset) {
-    assert(type == TokenType.OPEN_CURLY_BRACKET ||
-        type == TokenType.OPEN_PAREN ||
-        type == TokenType.OPEN_SQUARE_BRACKET ||
-        type == TokenType.STRING_INTERPOLATION_EXPRESSION);
-  }
-
-  @override
-  Token copy() => new BeginToken(type, offset);
-}
-
-/**
- * A begin token that is preceded by comments.
- */
-class BeginTokenWithComment extends BeginToken implements TokenWithComment {
-  /**
-   * The first comment in the list of comments that precede this token.
-   */
-  @override
-  CommentToken _precedingComment;
-
-  /**
-   * Initialize a newly created token to have the given [type] at the given
-   * [offset] and to be preceded by the comments reachable from the given
-   * [_precedingComment].
-   */
-  BeginTokenWithComment(TokenType type, int offset, this._precedingComment)
-      : super(type, offset) {
-    _setCommentParent(_precedingComment);
-  }
-
-  @override
-  CommentToken get precedingComments => _precedingComment;
-
-  @override
-  void set precedingComments(CommentToken comment) {
-    _precedingComment = comment;
-    _setCommentParent(_precedingComment);
-  }
-
-  @override
-  void applyDelta(int delta) {
-    super.applyDelta(delta);
-    Token token = precedingComments;
-    while (token != null) {
-      token.applyDelta(delta);
-      token = token.next;
-    }
-  }
-
-  @override
-  Token copy() =>
-      new BeginTokenWithComment(type, offset, copyComments(precedingComments));
-}
-
-/**
- * A token representing a comment.
- */
-class CommentToken extends StringToken {
-  /**
-   * The token that contains this comment.
-   */
-  TokenWithComment parent;
-
-  /**
-   * Initialize a newly created token to represent a token of the given [type]
-   * with the given [value] at the given [offset].
-   */
-  CommentToken(TokenType type, String value, int offset)
-      : super(type, value, offset);
-
-  @override
-  CommentToken copy() => new CommentToken(type, _value, offset);
-
-  /**
-   * Remove this comment token from the list.
-   *
-   * This is used when we decide to interpret the comment as syntax.
-   */
-  void remove() {
-    if (previous != null) {
-      previous.setNextWithoutSettingPrevious(next);
-      next?.previous = previous;
-    } else {
-      assert(parent.precedingComments == this);
-      parent.precedingComments = next;
-    }
-  }
-}
-
-/**
- * A documentation comment token.
- */
-class DocumentationCommentToken extends CommentToken {
-  /**
-   * The references embedded within the documentation comment.
-   * This list will be empty unless this is a documentation comment that has
-   * references embedded within it.
-   */
-  final List<Token> references = <Token>[];
-
-  /**
-   * Initialize a newly created token to represent a token of the given [type]
-   * with the given [value] at the given [offset].
-   */
-  DocumentationCommentToken(TokenType type, String value, int offset)
-      : super(type, value, offset);
-
-  @override
-  CommentToken copy() {
-    DocumentationCommentToken copy =
-        new DocumentationCommentToken(type, _value, offset);
-    references.forEach((ref) => copy.references.add(ref.copy()));
-    return copy;
-  }
-}
-
-/**
- * A token representing a keyword in the language.
- */
-class KeywordToken extends SimpleToken {
-  @override
-  final Keyword keyword;
-
-  /**
-   * Initialize a newly created token to represent the given [keyword] at the
-   * given [offset].
-   */
-  KeywordToken(this.keyword, int offset) : super(TokenType.KEYWORD, offset);
-
-  @override
-  String get lexeme => keyword.syntax;
-
-  @override
-  Token copy() => new KeywordToken(keyword, offset);
-
-  @override
-  Keyword value() => keyword;
-}
-
-/**
- * A keyword token that is preceded by comments.
- */
-class KeywordTokenWithComment extends KeywordToken implements TokenWithComment {
-  /**
-   * The first comment in the list of comments that precede this token.
-   */
-  @override
-  CommentToken _precedingComment;
-
-  /**
-   * Initialize a newly created token to to represent the given [keyword] at the
-   * given [offset] and to be preceded by the comments reachable from the given
-   * [_precedingComment].
-   */
-  KeywordTokenWithComment(Keyword keyword, int offset, this._precedingComment)
-      : super(keyword, offset) {
-    _setCommentParent(_precedingComment);
-  }
-
-  @override
-  CommentToken get precedingComments => _precedingComment;
-
-  void set precedingComments(CommentToken comment) {
-    _precedingComment = comment;
-    _setCommentParent(_precedingComment);
-  }
-
-  @override
-  void applyDelta(int delta) {
-    super.applyDelta(delta);
-    Token token = precedingComments;
-    while (token != null) {
-      token.applyDelta(delta);
-      token = token.next;
-    }
-  }
-
-  @override
-  Token copy() => new KeywordTokenWithComment(
-      keyword, offset, copyComments(precedingComments));
-}
-
-/**
- * A token that was scanned from the input. Each token knows which tokens
- * precede and follow it, acting as a link in a doubly linked list of tokens.
- */
-class SimpleToken implements Token {
-  /**
-   * The type of the token.
-   */
-  @override
-  final TokenType type;
-
-  /**
-   * The offset from the beginning of the file to the first character in the
-   * token.
-   */
-  @override
-  int offset = 0;
-
-  /**
-   * The previous token in the token stream.
-   */
-  @override
-  Token previous;
-
-  /**
-   * The next token in the token stream.
-   */
-  Token _next;
-
-  /**
-   * Initialize a newly created token to have the given [type] and [offset].
-   */
-  SimpleToken(this.type, this.offset);
-
-  @override
-  int get end => offset + length;
-
-  @override
-  bool get isOperator => type.isOperator;
-
-  @override
-  bool get isSynthetic => length == 0;
-
-  @override
-  bool get isUserDefinableOperator => type.isUserDefinableOperator;
-
-  @override
-  Keyword get keyword => null;
-
-  @override
-  int get length => lexeme.length;
-
-  @override
-  String get lexeme => type.lexeme;
-
-  @override
-  Token get next => _next;
-
-  @override
-  CommentToken get precedingComments => null;
-
-  @override
-  void applyDelta(int delta) {
-    offset += delta;
-  }
-
-  @override
-  Token copy() => new Token(type, offset);
-
-  @override
-  Token copyComments(Token token) {
-    if (token == null) {
-      return null;
-    }
-    Token head = token.copy();
-    Token tail = head;
-    token = token.next;
-    while (token != null) {
-      tail = tail.setNext(token.copy());
-      token = token.next;
-    }
-    return head;
-  }
-
-  @override
-  bool matchesAny(List<TokenType> types) {
-    for (TokenType type in types) {
-      if (this.type == type) {
-        return true;
-      }
-    }
-    return false;
-  }
-
-  @override
-  Token setNext(Token token) {
-    _next = token;
-    token.previous = this;
-    return token;
-  }
-
-  @override
-  Token setNextWithoutSettingPrevious(Token token) {
-    _next = token;
-    return token;
-  }
-
-  @override
-  String toString() => lexeme;
-
-  @override
-  Object value() => type.lexeme;
-
-  /**
-   * Sets the `parent` property to `this` for the given [comment] and all the
-   * next tokens.
-   */
-  void _setCommentParent(CommentToken comment) {
-    while (comment != null) {
-      comment.parent = this;
-      comment = comment.next;
-    }
-  }
-}
+export 'package:front_end/src/scanner/token.dart'
+    show
+        BeginToken,
+        BeginTokenWithComment,
+        CommentToken,
+        DocumentationCommentToken,
+        KeywordToken,
+        KeywordTokenWithComment,
+        SimpleToken,
+        StringToken,
+        StringTokenWithComment,
+        TokenClass,
+        TokenWithComment;
 
 /**
  * A token whose value is independent of it's type.
- */
-class StringToken extends SimpleToken {
-  /**
-   * The lexeme represented by this token.
-   */
-  String _value;
-
-  /**
-   * Initialize a newly created token to represent a token of the given [type]
-   * with the given [value] at the given [offset].
-   */
-  StringToken(TokenType type, String value, int offset) : super(type, offset) {
-    this._value = StringUtilities.intern(value);
-  }
-
-  @override
-  String get lexeme => _value;
-
-  @override
-  Token copy() => new StringToken(type, _value, offset);
-
-  @override
-  String value() => _value;
-}
-
-/**
- * A string token that is preceded by comments.
- */
-class StringTokenWithComment extends StringToken implements TokenWithComment {
-  /**
-   * The first comment in the list of comments that precede this token.
-   */
-  CommentToken _precedingComment;
-
-  /**
-   * Initialize a newly created token to have the given [type] at the given
-   * [offset] and to be preceded by the comments reachable from the given
-   * [comment].
-   */
-  StringTokenWithComment(
-      TokenType type, String value, int offset, this._precedingComment)
-      : super(type, value, offset) {
-    _setCommentParent(_precedingComment);
-  }
-
-  @override
-  CommentToken get precedingComments => _precedingComment;
-
-  void set precedingComments(CommentToken comment) {
-    _precedingComment = comment;
-    _setCommentParent(_precedingComment);
-  }
-
-  @override
-  void applyDelta(int delta) {
-    super.applyDelta(delta);
-    Token token = precedingComments;
-    while (token != null) {
-      token.applyDelta(delta);
-      token = token.next;
-    }
-  }
-
-  @override
-  Token copy() => new StringTokenWithComment(
-      type, lexeme, offset, copyComments(precedingComments));
-}
-
-/**
- * A token whose value is independent of it's type.
  */
 class SyntheticStringToken extends StringToken {
   /**
    * Initialize a newly created token to represent a token of the given [type]
    * with the given [value] at the given [offset].
    */
   SyntheticStringToken(TokenType type, String value, int offset)
       : super(type, value, offset);
 
   @override
   bool get isSynthetic => true;
 }
-
-/**
- * The classes (or groups) of tokens with a similar use.
- */
-class TokenClass {
-  /**
-   * A value used to indicate that the token type is not part of any specific
-   * class of token.
-   */
-  static const TokenClass NO_CLASS = const TokenClass('NO_CLASS');
-
-  /**
-   * A value used to indicate that the token type is an additive operator.
-   */
-  static const TokenClass ADDITIVE_OPERATOR =
-      const TokenClass('ADDITIVE_OPERATOR', 13);
-
-  /**
-   * A value used to indicate that the token type is an assignment operator.
-   */
-  static const TokenClass ASSIGNMENT_OPERATOR =
-      const TokenClass('ASSIGNMENT_OPERATOR', 1);
-
-  /**
-   * A value used to indicate that the token type is a bitwise-and operator.
-   */
-  static const TokenClass BITWISE_AND_OPERATOR =
-      const TokenClass('BITWISE_AND_OPERATOR', 11);
-
-  /**
-   * A value used to indicate that the token type is a bitwise-or operator.
-   */
-  static const TokenClass BITWISE_OR_OPERATOR =
-      const TokenClass('BITWISE_OR_OPERATOR', 9);
-
-  /**
-   * A value used to indicate that the token type is a bitwise-xor operator.
-   */
-  static const TokenClass BITWISE_XOR_OPERATOR =
-      const TokenClass('BITWISE_XOR_OPERATOR', 10);
-
-  /**
-   * A value used to indicate that the token type is a cascade operator.
-   */
-  static const TokenClass CASCADE_OPERATOR =
-      const TokenClass('CASCADE_OPERATOR', 2);
-
-  /**
-   * A value used to indicate that the token type is a conditional operator.
-   */
-  static const TokenClass CONDITIONAL_OPERATOR =
-      const TokenClass('CONDITIONAL_OPERATOR', 3);
-
-  /**
-   * A value used to indicate that the token type is an equality operator.
-   */
-  static const TokenClass EQUALITY_OPERATOR =
-      const TokenClass('EQUALITY_OPERATOR', 7);
-
-  /**
-   * A value used to indicate that the token type is an if-null operator.
-   */
-  static const TokenClass IF_NULL_OPERATOR =
-      const TokenClass('IF_NULL_OPERATOR', 4);
-
-  /**
-   * A value used to indicate that the token type is a logical-and operator.
-   */
-  static const TokenClass LOGICAL_AND_OPERATOR =
-      const TokenClass('LOGICAL_AND_OPERATOR', 6);
-
-  /**
-   * A value used to indicate that the token type is a logical-or operator.
-   */
-  static const TokenClass LOGICAL_OR_OPERATOR =
-      const TokenClass('LOGICAL_OR_OPERATOR', 5);
-
-  /**
-   * A value used to indicate that the token type is a multiplicative operator.
-   */
-  static const TokenClass MULTIPLICATIVE_OPERATOR =
-      const TokenClass('MULTIPLICATIVE_OPERATOR', 14);
-
-  /**
-   * A value used to indicate that the token type is a relational operator.
-   */
-  static const TokenClass RELATIONAL_OPERATOR =
-      const TokenClass('RELATIONAL_OPERATOR', 8);
-
-  /**
-   * A value used to indicate that the token type is a shift operator.
-   */
-  static const TokenClass SHIFT_OPERATOR =
-      const TokenClass('SHIFT_OPERATOR', 12);
-
-  /**
-   * A value used to indicate that the token type is a unary operator.
-   */
-  static const TokenClass UNARY_POSTFIX_OPERATOR =
-      const TokenClass('UNARY_POSTFIX_OPERATOR', 16);
-
-  /**
-   * A value used to indicate that the token type is a unary operator.
-   */
-  static const TokenClass UNARY_PREFIX_OPERATOR =
-      const TokenClass('UNARY_PREFIX_OPERATOR', 15);
-
-  /**
-   * The name of the token class.
-   */
-  final String name;
-
-  /**
-   * The precedence of tokens of this class, or `0` if the such tokens do not
-   * represent an operator.
-   */
-  final int precedence;
-
-  /**
-   * Initialize a newly created class of tokens to have the given [name] and
-   * [precedence].
-   */
-  const TokenClass(this.name, [this.precedence = 0]);
-
-  @override
-  String toString() => name;
-}
-
-/**
- * A normal token that is preceded by comments.
- */
-class TokenWithComment extends SimpleToken {
-  /**
-   * The first comment in the list of comments that precede this token.
-   */
-  CommentToken _precedingComment;
-
-  /**
-   * Initialize a newly created token to have the given [type] at the given
-   * [offset] and to be preceded by the comments reachable from the given
-   * [comment].
-   */
-  TokenWithComment(TokenType type, int offset, this._precedingComment)
-      : super(type, offset) {
-    _setCommentParent(_precedingComment);
-  }
-
-  @override
-  CommentToken get precedingComments => _precedingComment;
-
-  void set precedingComments(CommentToken comment) {
-    _precedingComment = comment;
-    _setCommentParent(_precedingComment);
-  }
-
-  @override
-  Token copy() =>
-      new TokenWithComment(type, offset, copyComments(precedingComments));
-}