Support for observable models, fixes #259

lib/src/directive_parser.dart

Index: lib/src/directive_parser.dart
diff --git a/lib/src/directive_parser.dart b/lib/src/directive_parser.dart
deleted file mode 100644
index 53377352a28c11ed9cc5548b1e6d492ef491dcd8..0000000000000000000000000000000000000000
--- a/lib/src/directive_parser.dart
+++ /dev/null
@@ -1,388 +0,0 @@
-// Copyright (c) 2012, 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.
-
-/**
- * A mini parser that extracts top-level directives (library, imports, exports,
- * and parts) from a dart source file.
- */
-library directive_parser;
-
-import 'info.dart' show DartCodeInfo, DartDirectiveInfo;
-import 'messages.dart' show Messages;
-import 'file_system/path.dart';
-
-/**
- * Parse and extract top-level directives from [code].
- *
- * Adds emitted error/warning messages to [messages], if [messages] is
- * supplied.
- */
-DartCodeInfo parseDartCode(String code, Path file, {Messages messages}) {
-  messages = messages == null ? new Messages.silent() : messages;
-  return new _DirectiveParser(messages, file).parse(code);
-}
-
-/** A parser that extracts top-level directives. */
-// TODO(sigmund): add source-span to error messages
-class _DirectiveParser {
-  /** Path to the source file containing the code (for error messages). */
-  Path file;
-
-  /** Tokenizer used to parse the input until the end of the directives. */
-  _DirectiveTokenizer tokenizer;
-
-  /** Extracted library identifier, if any. */
-  String libraryName;
-
-  /** Extracted part-of identifier, if any. */
-  String partName;
-
-  /** Extracted imports, exports, and parts, if any. */
-  List<DartDirectiveInfo> directives = <DartDirectiveInfo>[];
-
-  /** Helper for reporting error messages. */
-  Messages messages;
-
-  /** Last token read by the parser. */
-  Token token;
-
-  _DirectiveParser(this.messages, this.file);
-
-  /** Parse and extract directives from [code]. */
-  DartCodeInfo parse(String code) {
-    tokenizer = new _DirectiveTokenizer(code);
-    parseTopLevel();
-    return new DartCodeInfo(libraryName, partName, directives,
-        code.substring(token.start));
-  }
-
-  /**
-   * Parse top-level directives and comments, but unlike normal Dart code, stop
-   * as soon as we find actual code.
-   */
-  void parseTopLevel() {
-    token = tokenizer.next();
-    while (token.kind != Token.EOF) {
-      if (token.kind == Token.IDENTIFIER) {
-        if (token.value == 'library') {
-          parseLibrary();
-        } else if (token.value == 'part') {
-          parsePart();
-        } else if (token.value == 'import') {
-          parseImport();
-        } else if (token.value == 'export') {
-          parseExport();
-        } else {
-          break;
-        }
-      } else if (token.kind != Token.COMMENT) {
-        break;
-      }
-      token = tokenizer.next();
-    }
-  }
-
-  /** Parse library declarations: 'library foo.bar;' */
-  parseLibrary() {
-    libraryName = parseQualifiedName();
-    expectToken(Token.SEMICOLON);
-  }
-
-  /**
-   * Parse either a part declaration or part inclusions. For instance,
-   *     part of foo.bar;
-   * or
-   *     part "foo";
-   */
-  parsePart() {
-    token = tokenizer.next();
-    if (token.kind == Token.IDENTIFIER && token.value == 'of') {
-      partName = parseQualifiedName();
-    } else if (token.kind == Token.STRING) {
-      directives.add(new DartDirectiveInfo('part', token.value));
-      token = tokenizer.next();
-    } else {
-      messages.error('unexpected token: ${token}', null, file: file);
-    }
-    expectToken(Token.SEMICOLON);
-  }
-
-  /** Parse a qualified name, such as `one.two.three`. */
-  parseQualifiedName() {
-    List<String> segments = [];
-    while (true) {
-      token = tokenizer.next();
-      if (token.kind != Token.IDENTIFIER) {
-        messages.error('invalid qualified name: $token', null, file: file);
-        return null;
-      }
-      segments.add(token.value);
-      token = tokenizer.next();
-      if (token.kind == Token.SEMICOLON) break;
-      if (token.kind != Token.DOT) {
-        messages.error('invalid qualified name: $token', null, file: file);
-        return null;
-      }
-    }
-    return segments.join('.');
-  }
-
-  /** Parse an import, with optional prefix and show/hide combinators. */
-  parseImport() {
-    token = tokenizer.next();
-    if (token.kind != Token.STRING) {
-      // TODO(sigmund): add file name and span information here.
-      messages.error('expected an import url, but found ${token}', null,
-          file: file);
-      return;
-    }
-    var uri = token.value;
-    token = tokenizer.next();
-    while (token.kind == Token.STRING) {
-      uri = '$uri${token.value}';
-      token = tokenizer.next();
-    }
-
-    // Parse the optional prefix.
-    var prefix;
-    if (token.kind == Token.IDENTIFIER && token.value == 'as') {
-      token = tokenizer.next();
-      if (token.kind != Token.IDENTIFIER) {
-        messages.error('expected an identifier as prefix, but found ${token}',
-            null, file: file);
-        return;
-      }
-      prefix = token.value;
-      token = tokenizer.next();
-    }
-
-    // Parse the optional show/hide combinators.
-    var hide;
-    var show;
-    while (token.kind == Token.IDENTIFIER) {
-      if (token.value == 'hide') {
-        if (hide == null) hide = [];
-        hide.addAll(parseIdentifierList());
-      } else if (token.value == 'show') {
-        if (show == null) show = [];
-        show.addAll(parseIdentifierList());
-      } else {
-        break;
-      }
-    }
-
-    expectToken(Token.SEMICOLON);
-    directives.add(new DartDirectiveInfo('import', uri, prefix, hide, show));
-  }
-
-  /** Parse an export, with optional show/hide combinators. */
-  parseExport() {
-    token = tokenizer.next();
-    if (token.kind != Token.STRING) {
-      messages.error('expected an export url, but found ${token}', null,
-          file: file);
-      return;
-    }
-    var uri = token.value;
-
-    // Parse the optional show/hide combinators.
-    token = tokenizer.next();
-    var hide;
-    var show;
-    while (token.kind == Token.IDENTIFIER) {
-      if (token.value == 'hide') {
-        if (hide == null) hide = [];
-        hide.addAll(parseIdentifierList());
-      } else if (token.value == 'show') {
-        if (show == null) show = [];
-        show.addAll(parseIdentifierList());
-      }
-    }
-
-    expectToken(Token.SEMICOLON);
-    directives.add(new DartDirectiveInfo('export', uri, null, hide, show));
-  }
-
-  /** Parse a list of identifiers of the form `id1, id2, id3` */
-  List<String> parseIdentifierList() {
-    var list = [];
-    do {
-      token = tokenizer.next();
-      if (!expectToken(Token.IDENTIFIER)) return list;
-      list.add(token.value);
-      token = tokenizer.next();
-    } while (token.kind == Token.COMMA);
-    return list;
-  }
-
-  /** Report an error if the last token is not of the expected kind. */
-  bool expectToken(int kind) {
-    if (token.kind != kind) {
-      messages.error(
-          'expected <${Token.KIND_NAMES[kind]}>, but got ${token}', null,
-          file: file);
-      return false;
-    }
-    return true;
-  }
-}
-
-/** Set of tokens that we parse out of the dart code. */
-class Token {
-  /** Kind of token, one of the constants below. */
-  final int kind;
-
-  /** Value in the token (filled only for identifiers and strings). */
-  final String value;
-
-  /** Start location for the token in the input string. */
-  final int start;
-
-  /** End location for the token in the input string. */
-  final int end;
-
-  const Token(this.kind, this.start, this.end, [this.value]);
-
-  toString() => '<#Token ${KIND_NAMES[kind]}, $value>';
-
-  static const int COMMENT = 0;
-  static const int STRING = 1;
-  static const int IDENTIFIER = 2;
-  static const int SEMICOLON = 3;
-  static const int DOT = 4;
-  static const int COMMA = 5;
-  static const int EOF = 6;
-  static const List<String> KIND_NAMES =
-      const ['comment', 'string', 'id', 'semicolon', 'dot', 'comma', 'eof'];
-
-}
-
-/**
- * A simple tokenizer that understands comments, identifiers, strings,
- * separators, and practically nothing else.
- */
-class _DirectiveTokenizer {
-  int pos = 0;
-  String _data;
-
-  _DirectiveTokenizer(this._data);
-
-  /** Return the next token. */
-  Token next() {
-    while (true) {
-      if (pos >= _data.length) return new Token(Token.EOF, pos, pos);
-      if (!isWhiteSpace(peek())) break;
-      nextChar();
-    }
-
-    var c = peek();
-    switch (c) {
-      case _SLASH:
-        if (peek(1) == _SLASH) return lineComment();
-        if (peek(1) == _STAR) return blockComment();
-        break;
-      case _SINGLE_QUOTE:
-      case _DOUBLE_QUOTE:
-        return string();
-      case _SEMICOLON:
-        pos++;
-        return new Token(Token.SEMICOLON, pos - 1, pos);
-      case _DOT:
-        pos++;
-        return new Token(Token.DOT, pos - 1, pos);
-      case _COMMA:
-        pos++;
-        return new Token(Token.COMMA, pos - 1, pos);
-      default:
-        if (isIdentifierStart(c)) return identifier();
-        break;
-    }
-    return new Token(Token.EOF, pos, pos);
-  }
-
-  int nextChar() => _data.charCodeAt(pos++);
-  int peek([int skip = 0]) => _data.charCodeAt(pos + skip);
-
-  /** Advance parsing until the end of a string (no tripple quotes allowed). */
-  Token string() {
-    // TODO(sigmund): add support for multi-line strings, and raw strings.
-    int start = pos;
-    int startQuote = nextChar();
-    bool escape = false;
-    while (true) {
-      if (pos >= _data.length) return new Token(Token.EOF, start, pos);
-      int c = nextChar();
-      if (c == startQuote && !escape) break;
-      escape = !escape && c == _BACKSLASH;
-    }
-    return new Token(Token.STRING, start, pos,
-        _data.substring(start + 1, pos - 1));
-  }
-
-  /** Advance parsing until the end of an identifier. */
-  Token identifier() {
-    int start = pos;
-    while (pos < _data.length && isIdentifierChar(peek())) pos++;
-    return new Token(Token.IDENTIFIER, start, pos, _data.substring(start, pos));
-  }
-
-  /** Advance parsing until the end of a line comment. */
-  Token lineComment() {
-    int start = pos;
-    while (pos < _data.length && peek() != _LF) pos++;
-    return new Token(Token.COMMENT, start, pos);
-  }
-
-  /** Advance parsing until the end of a block comment (nesting is allowed). */
-  Token blockComment() {
-    var start = pos;
-    var commentNesting = 0;
-    pos += 2;
-    while (pos < _data.length) {
-      if (peek() == _STAR && peek(1) == _SLASH) {
-        pos += 2;
-        if (commentNesting == 0) break;
-        commentNesting--;
-      } else if (peek() == _SLASH && peek(1) == _STAR) {
-        pos += 2;
-        commentNesting++;
-      } else {
-        pos++;
-      }
-    }
-    return new Token(Token.COMMENT, start, pos);
-  }
-
-  bool isWhiteSpace(int c) => c == _LF || c == _SPACE || c == _CR || c == _TAB;
-  bool isIdentifierStart(int c) => c == _UNDERSCORE || isLetter(c);
-  bool isIdentifierChar(int c) => isIdentifierStart(c) || isNumber(c);
-  bool isNumber(int c) => c >= _ZERO && c <= _NINE;
-  bool isLetter(int c) =>
-      (c >= _LOWER_A && c <= _LOWER_Z) ||
-      (c >= _UPPER_A && c <= _UPPER_Z);
-
-
-  // The following constant character values are used for tokenizing.
-
-  static const int _TAB = 9;
-  static const int _LF = 10;
-  static const int _CR = 13;
-  static const int _SPACE = 32;
-  static const int _DOUBLE_QUOTE = 34; // "
-  static const int _DOLLAR = 36;       // $
-  static const int _SINGLE_QUOTE = 39; // '
-  static const int _STAR = 42;         // *
-  static const int _COMMA = 44;        // ,
-  static const int _DOT = 46;          // .
-  static const int _SLASH = 47;        // /
-  static const int _ZERO = 48;         // 0
-  static const int _NINE = 57;         // 9
-  static const int _SEMICOLON = 59;    // ;
-  static const int _UPPER_A = 65;      // A
-  static const int _UPPER_Z = 90;      // Z
-  static const int _BACKSLASH = 92;    // \
-  static const int _UNDERSCORE = 95;   // _
-  static const int _LOWER_A = 97;      // a
-  static const int _LOWER_Z = 122;     // z
-}