Linter Demo

Errors: 2

Warnings: 17

File: /home/fstrocco/Dart/dart/benchmark/analyzer/lib/src/generated/html.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. // This code was auto-generated, is not intended to be edited, and is subject to // significant change. Please see the README file for more information. library engine.html; import 'dart:collection'; import 'ast.dart'; import 'element.dart'; import 'engine.dart' show AnalysisOptions, AnalysisEngine; import 'error.dart' show AnalysisErrorListener; import 'java_core.dart'; import 'java_engine.dart'; import 'parser.dart' show Parser; import 'scanner.dart' as sc show Scanner, SubSequenceReader, Token; import 'source.dart'; /** * The abstract class `AbstractScanner` implements a scanner for HTML code. Subclasses are * required to implement the interface used to access the characters being scanned. */ abstract class AbstractScanner { static List<String> _NO_PASS_THROUGH_ELEMENTS = <String>[]; /** * The source being scanned. */ final Source source; /** * The token pointing to the head of the linked list of tokens. */ Token _tokens; /** * The last token that was scanned. */ Token _tail; /** * A list containing the offsets of the first character of each line in the source code. */ List<int> _lineStarts = new List<int>(); /** * An array of element tags for which the content between tags should be consider a single token. */ List<String> _passThroughElements = _NO_PASS_THROUGH_ELEMENTS; /** * Initialize a newly created scanner. * * @param source the source being scanned */ AbstractScanner(this.source) { _tokens = new Token.con1(TokenType.EOF, -1); _tokens.setNext(_tokens); _tail = _tokens; recordStartOfLine(); } /** * Return an array containing the offsets of the first character of each line in the source code. * * @return an array containing the offsets of the first character of each line in the source code */ List<int> get lineStarts => _lineStarts; /** * Return the current offset relative to the beginning of the file. Return the initial offset if * the scanner has not yet scanned the source code, and one (1) past the end of the source code if * the source code has been scanned. * * @return the current offset of the scanner in the source */ int get offset; /** * Set array of element tags for which the content between tags should be consider a single token. */ void set passThroughElements(List<String> passThroughElements) { this._passThroughElements = passThroughElements != null ? passThroughElements : _NO_PASS_THROUGH_ELEMENTS; } /** * Advance the current position and return the character at the new current position. * * @return the character at the new current position */ int advance(); /** * Return the substring of the source code between the start offset and the modified current * position. The current position is modified by adding the end delta. * * @param start the offset to the beginning of the string, relative to the start of the file * @param endDelta the number of character after the current location to be included in the * string, or the number of characters before the current location to be excluded if the * offset is negative * @return the specified substring of the source code */ String getString(int start, int endDelta); /** * Return the character at the current position without changing the current position. * * @return the character at the current position */ int peek(); /** * Record the fact that we are at the beginning of a new line in the source. */ void recordStartOfLine() { _lineStarts.add(offset); } /** * Scan the source code to produce a list of tokens representing the source. * * @return the first token in the list of tokens that were produced */ Token tokenize() { _scan(); _appendEofToken(); return _firstToken(); } void _appendEofToken() { Token eofToken = new Token.con1(TokenType.EOF, offset); // The EOF token points to itself so that there is always infinite // look-ahead. eofToken.setNext(eofToken); _tail = _tail.setNext(eofToken); } Token _emit(Token token) { _tail.setNext(token); _tail = token; return token; } Token _emitWithOffset(TokenType type, int start) => _emit(new Token.con1(type, start)); Token _emitWithOffsetAndLength(TokenType type, int start, int count) => _emit(new Token.con2(type, start, getString(start, count))); Token _firstToken() => _tokens.next; int _recordStartOfLineAndAdvance(int c) { if (c == 0xD) { c = advance(); if (c == 0xA) { c = advance(); } recordStartOfLine(); } else if (c == 0xA) { c = advance(); recordStartOfLine(); } else { c = advance(); } return c; } void _scan() { bool inBrackets = false; String endPassThrough = null; int c = advance(); while (c >= 0) { int start = offset; if (c == 0x3C) { c = advance(); if (c == 0x21) { c = advance(); if (c == 0x2D && peek() == 0x2D) { // handle a comment c = advance(); int dashCount = 1; while (c >= 0) { if (c == 0x2D) { dashCount++; } else if (c == 0x3E && dashCount >= 2) { c = advance(); break; } else { dashCount = 0; } c = _recordStartOfLineAndAdvance(c); } _emitWithOffsetAndLength(TokenType.COMMENT, start, -1); // Capture <!--> and <!---> as tokens but report an error if (_tail.length < 7) { // TODO (danrubel): Report invalid HTML comment } } else { // handle a declaration while (c >= 0) { if (c == 0x3E) { c = advance(); break; } c = _recordStartOfLineAndAdvance(c); } _emitWithOffsetAndLength(TokenType.DECLARATION, start, -1); if (!StringUtilities.endsWithChar(_tail.lexeme, 0x3E)) { // TODO (danrubel): Report missing '>' in directive } } } else if (c == 0x3F) { // handle a directive while (c >= 0) { if (c == 0x3F) { c = advance(); if (c == 0x3E) { c = advance(); break; } } else { c = _recordStartOfLineAndAdvance(c); } } _emitWithOffsetAndLength(TokenType.DIRECTIVE, start, -1); if (_tail.length < 4) { // TODO (danrubel): Report invalid directive } } else if (c == 0x2F) { _emitWithOffset(TokenType.LT_SLASH, start); inBrackets = true; c = advance(); } else { inBrackets = true; _emitWithOffset(TokenType.LT, start); // ignore whitespace in braces while (Character.isWhitespace(c)) { c = _recordStartOfLineAndAdvance(c); } // get tag if (Character.isLetterOrDigit(c)) { int tagStart = offset; c = advance(); while (Character.isLetterOrDigit(c) || c == 0x2D || c == 0x5F) { c = advance(); } _emitWithOffsetAndLength(TokenType.TAG, tagStart, -1); // check tag against passThrough elements String tag = _tail.lexeme; for (String str in _passThroughElements) { if (str == tag) { endPassThrough = "</$str>"; break; } } } } } else if (c == 0x3E) { _emitWithOffset(TokenType.GT, start); inBrackets = false; c = advance(); // if passThrough != null, read until we match it if (endPassThrough != null) { bool endFound = false; int len = endPassThrough.length; int firstC = endPassThrough.codeUnitAt(0); int index = 0; int nextC = firstC; while (c >= 0) { if (c == nextC) { index++; if (index == len) { endFound = true; break; } nextC = endPassThrough.codeUnitAt(index); } else if (c == firstC) { index = 1; nextC = endPassThrough.codeUnitAt(1); } else { index = 0; nextC = firstC; } c = _recordStartOfLineAndAdvance(c); } if (start + 1 < offset) { if (endFound) { _emitWithOffsetAndLength(TokenType.TEXT, start + 1, -len); _emitWithOffset(TokenType.LT_SLASH, offset - len + 1); _emitWithOffsetAndLength(TokenType.TAG, offset - len + 3, -1); } else { _emitWithOffsetAndLength(TokenType.TEXT, start + 1, -1); } } endPassThrough = null; } } else if (c == 0x2F && peek() == 0x3E) { advance(); _emitWithOffset(TokenType.SLASH_GT, start); inBrackets = false; c = advance(); } else if (!inBrackets) { c = _recordStartOfLineAndAdvance(c); while (c != 0x3C && c >= 0) { c = _recordStartOfLineAndAdvance(c); } _emitWithOffsetAndLength(TokenType.TEXT, start, -1); } else if (c == 0x22 || c == 0x27) { // read a string int endQuote = c; c = advance(); while (c >= 0) { if (c == endQuote) { c = advance(); break; } c = _recordStartOfLineAndAdvance(c); } _emitWithOffsetAndLength(TokenType.STRING, start, -1); } else if (c == 0x3D) { // a non-char token _emitWithOffset(TokenType.EQ, start); c = advance(); } else if (Character.isWhitespace(c)) { // ignore whitespace in braces do { c = _recordStartOfLineAndAdvance(c); } while (Character.isWhitespace(c)); } else if (Character.isLetterOrDigit(c)) { c = advance(); while (Character.isLetterOrDigit(c) || c == 0x2D || c == 0x5F) { c = advance(); } _emitWithOffsetAndLength(TokenType.TAG, start, -1); } else { // a non-char token _emitWithOffsetAndLength(TokenType.TEXT, start, 0); c = advance(); } } } } /** * Instances of the class `HtmlParser` are used to parse tokens into a AST structure comprised * of [XmlNode]s. */ class HtmlParser extends XmlParser { static String _APPLICATION_DART_IN_DOUBLE_QUOTES = "\"application/dart\""; static String _APPLICATION_DART_IN_SINGLE_QUOTES = "'application/dart'"; static String _SCRIPT = "script"; static String _TYPE = "type"; /** * A set containing the names of tags that do not have a closing tag. */ static Set<String> SELF_CLOSING = new HashSet<String>.from(<String>[ "area", "base", "basefont", "br", "col", "frame", "hr", "img", "input", "link", "meta", "param", "!" ]); /** * The line information associated with the source being parsed. */ LineInfo _lineInfo; /** * The error listener to which errors will be reported. */ final AnalysisErrorListener _errorListener; final AnalysisOptions _options; /** * Construct a parser for the specified source. * * [source] is the source being parsed. [_errorListener] is the error * listener to which errors will be reported. [_options] is the analysis * options which should be used for parsing. */ HtmlParser(Source source, this._errorListener, this._options) : super(source); @override XmlAttributeNode createAttributeNode(Token name, Token equals, Token value) => new XmlAttributeNode(name, equals, value); @override XmlTagNode createTagNode(Token nodeStart, Token tag, List<XmlAttributeNode> attributes, Token attributeEnd, List<XmlTagNode> tagNodes, Token contentEnd, Token closingTag, Token nodeEnd) { if (_isScriptNode(tag, attributes, tagNodes)) { HtmlScriptTagNode tagNode = new HtmlScriptTagNode(nodeStart, tag, attributes, attributeEnd, tagNodes, contentEnd, closingTag, nodeEnd); String contents = tagNode.content; int contentOffset = attributeEnd.end; LineInfo_Location location = _lineInfo.getLocation(contentOffset); sc.Scanner scanner = new sc.Scanner(source, new sc.SubSequenceReader(contents, contentOffset), _errorListener); scanner.enableNullAwareOperators = _options.enableNullAwareOperators; scanner.setSourceStart(location.lineNumber, location.columnNumber); sc.Token firstToken = scanner.tokenize(); Parser parser = new Parser(source, _errorListener); CompilationUnit unit = parser.parseCompilationUnit(firstToken); unit.lineInfo = _lineInfo; tagNode.script = unit; return tagNode; } return new XmlTagNode(nodeStart, tag, attributes, attributeEnd, tagNodes, contentEnd, closingTag, nodeEnd); } @override bool isSelfClosing(Token tag) => SELF_CLOSING.contains(tag.lexeme); /** * Parse the given tokens. * * @param token the first token in the stream of tokens to be parsed * @param lineInfo the line information created by the scanner * @return the parse result (not `null`) */ HtmlUnit parse(Token token, LineInfo lineInfo) { this._lineInfo = lineInfo; List<XmlTagNode> tagNodes = parseTopTagNodes(token); return new HtmlUnit(token, tagNodes, currentToken); } /** * Determine if the specified node is a Dart script. * * @param node the node to be tested (not `null`) * @return `true` if the node is a Dart script */ bool _isScriptNode( Token tag, List<XmlAttributeNode> attributes, List<XmlTagNode> tagNodes) { if (tagNodes.length != 0 || tag.lexeme != _SCRIPT) { return false; } for (XmlAttributeNode attribute in attributes) { if (attribute.name == _TYPE) { Token valueToken = attribute.valueToken; if (valueToken != null) { String value = valueToken.lexeme; if (value == _APPLICATION_DART_IN_DOUBLE_QUOTES || value == _APPLICATION_DART_IN_SINGLE_QUOTES) { return true; } } } } return false; } /** * Given the contents of an embedded expression that occurs at the given offset, parse it as a * Dart expression. The contents should not include the expression's delimiters. * * @param source the source that contains that given token * @param token the token to start parsing from * @return the Dart expression that was parsed */ static Expression parseEmbeddedExpression( Source source, sc.Token token, AnalysisErrorListener errorListener) { Parser parser = new Parser(source, errorListener); return parser.parseExpression(token); } /** * Given the contents of an embedded expression that occurs at the given offset, scans it as a * Dart code. * * @param source the source of that contains the given contents * @param contents the contents to scan * @param contentOffset the offset of the contents in the larger file * @return the first Dart token */ static sc.Token scanDartSource(Source source, LineInfo lineInfo, String contents, int contentOffset, AnalysisErrorListener errorListener) { LineInfo_Location location = lineInfo.getLocation(contentOffset); sc.Scanner scanner = new sc.Scanner(source, new sc.SubSequenceReader(contents, contentOffset), errorListener); scanner.setSourceStart(location.lineNumber, location.columnNumber); return scanner.tokenize(); } } /** * Instances of the class `HtmlScriptTagNode` represent a script tag within an HTML file that * references a Dart script. */ class HtmlScriptTagNode extends XmlTagNode { /** * The AST structure representing the Dart code within this tag. */ CompilationUnit _script; /** * The element representing this script. */ HtmlScriptElement scriptElement; /** * Initialize a newly created node to represent a script tag within an HTML file that references a * Dart script. * * @param nodeStart the token marking the beginning of the tag * @param tag the name of the tag * @param attributes the attributes in the tag * @param attributeEnd the token terminating the region where attributes can be * @param tagNodes the children of the tag * @param contentEnd the token that starts the closing tag * @param closingTag the name of the tag that occurs in the closing tag * @param nodeEnd the last token in the tag */ HtmlScriptTagNode(Token nodeStart, Token tag, List<XmlAttributeNode> attributes, Token attributeEnd, List<XmlTagNode> tagNodes, Token contentEnd, Token closingTag, Token nodeEnd) : super(nodeStart, tag, attributes, attributeEnd, tagNodes, contentEnd, closingTag, nodeEnd); /** * Return the AST structure representing the Dart code within this tag, or `null` if this * tag references an external script. * * @return the AST structure representing the Dart code within this tag */ CompilationUnit get script => _script; /** * Set the AST structure representing the Dart code within this tag to the given compilation unit. * * @param unit the AST structure representing the Dart code within this tag */ void set script(CompilationUnit unit) { _script = unit; } @override accept(XmlVisitor visitor) => visitor.visitHtmlScriptTagNode(this); } /** * Instances of the class `HtmlUnit` represent the contents of an HTML file. */ class HtmlUnit extends XmlNode { /** * The first token in the token stream that was parsed to form this HTML unit. */ final Token beginToken; /** * The last token in the token stream that was parsed to form this compilation unit. This token * should always have a type of [TokenType.EOF]. */ final Token endToken; /** * The tag nodes contained in the receiver (not `null`, contains no `null`s). */ List<XmlTagNode> _tagNodes; /** * Construct a new instance representing the content of an HTML file. * * @param beginToken the first token in the file (not `null`) * @param tagNodes child tag nodes of the receiver (not `null`, contains no `null`s) * @param endToken the last token in the token stream which should be of type * [TokenType.EOF] */ HtmlUnit(this.beginToken, List<XmlTagNode> tagNodes, this.endToken) { this._tagNodes = becomeParentOfAll(tagNodes); } /** * Return the element associated with this HTML unit. * * @return the element or `null` if the receiver is not resolved */ @override HtmlElement get element => super.element as HtmlElement; @override void set element(Element element) { if (element != null && element is! HtmlElement) { throw new IllegalArgumentException( "HtmlElement expected, but ${element.runtimeType} given"); } super.element = element; } /** * Answer the tag nodes contained in the receiver. Callers should not manipulate the returned list * to edit the AST structure. * * @return the children (not `null`, contains no `null`s) */ List<XmlTagNode> get tagNodes => _tagNodes; @override accept(XmlVisitor visitor) => visitor.visitHtmlUnit(this); @override void visitChildren(XmlVisitor visitor) { for (XmlTagNode node in _tagNodes) { node.accept(visitor); } } } /** * Instances of the class `RecursiveXmlVisitor` implement an XML visitor that will recursively * visit all of the nodes in an XML structure. For example, using an instance of this class to visit * a [XmlTagNode] will also cause all of the contained [XmlAttributeNode]s and * [XmlTagNode]s to be visited. * * Subclasses that override a visit method must either invoke the overridden visit method or must * explicitly ask the visited node to visit its children. Failure to do so will cause the children * of the visited node to not be visited. */ class RecursiveXmlVisitor<R> implements XmlVisitor<R> { @override R visitHtmlScriptTagNode(HtmlScriptTagNode node) { node.visitChildren(this); return null; } @override R visitHtmlUnit(HtmlUnit node) { node.visitChildren(this); return null; } @override R visitXmlAttributeNode(XmlAttributeNode node) { node.visitChildren(this); return null; } @override R visitXmlTagNode(XmlTagNode node) { node.visitChildren(this); return null; } } /** * Instances of the class `SimpleXmlVisitor` implement an AST visitor that will do nothing * when visiting an AST node. It is intended to be a superclass for classes that use the visitor * pattern primarily as a dispatch mechanism (and hence don't need to recursively visit a whole * structure) and that only need to visit a small number of node types. */ class SimpleXmlVisitor<R> implements XmlVisitor<R> { @override R visitHtmlScriptTagNode(HtmlScriptTagNode node) => null; @override R visitHtmlUnit(HtmlUnit htmlUnit) => null; @override R visitXmlAttributeNode(XmlAttributeNode xmlAttributeNode) => null; @override R visitXmlTagNode(XmlTagNode xmlTagNode) => null; } /** * Instances of the class `StringScanner` implement a scanner that reads from a string. The * scanning logic is in the superclass. */ class StringScanner extends AbstractScanner { /** * The string from which characters will be read. */ final String _string; /** * The number of characters in the string. */ int _stringLength = 0; /** * The index, relative to the string, of the last character that was read. */ int _charOffset = 0; /** * Initialize a newly created scanner to scan the characters in the given string. * * @param source the source being scanned * @param string the string from which characters will be read */ StringScanner(Source source, this._string) : super(source) { this._stringLength = _string.length; this._charOffset = -1; } @override int get offset => _charOffset; void set offset(int offset) { _charOffset = offset; } @override int advance() { if (++_charOffset < _stringLength) { return _string.codeUnitAt(_charOffset); } _charOffset = _stringLength; return -1; } @override String getString(int start, int endDelta) => _string.substring(start, _charOffset + 1 + endDelta).toString(); @override int peek() { if (_charOffset + 1 < _stringLength) { return _string.codeUnitAt(_charOffset + 1); } return -1; } } /** * Instances of the class `Token` represent a token that was scanned from the input. Each * token knows which token follows it, acting as the head of a linked list of tokens. */ class Token { /** * The offset from the beginning of the file to the first character in the token. */ final int offset; /** * The previous token in the token stream. */ Token previous; /** * The next token in the token stream. */ Token _next; /** * The type of the token. */ final TokenType type; /** * The lexeme represented by this token. */ String _value; /** * Initialize a newly created token. * * @param type the token type (not `null`) * @param offset the offset from the beginning of the file to the first character in the token */ Token.con1(TokenType type, int offset) : this.con2(type, offset, type.lexeme); /** * Initialize a newly created token. * * @param type the token type (not `null`) * @param offset the offset from the beginning of the file to the first character in the token * @param value the lexeme represented by this token (not `null`) */ Token.con2(this.type, this.offset, String value) { this._value = StringUtilities.intern(value); } /** * Return the offset from the beginning of the file to the character after last character of the * token. * * @return the offset from the beginning of the file to the first character after last character * of the token */ int get end => offset + length; /** * Return `true` if this token is a synthetic token. A synthetic token is a token that was * introduced by the parser in order to recover from an error in the code. Synthetic tokens always * have a length of zero (`0`). * * @return `true` if this token is a synthetic token */ bool get isSynthetic => length == 0; /** * Return the number of characters in the node's source range. * * @return the number of characters in the node's source range */ int get length => lexeme.length; /** * Return the lexeme that represents this token. * * @return the lexeme (not `null`) */ String get lexeme => _value; /** * Return the next token in the token stream. * * @return the next token in the token stream */ Token get next => _next; /** * Set the next token in the token stream to the given token. This has the side-effect of setting * this token to be the previous token for the given token. * * @param token the next token in the token stream * @return the token that was passed in */ Token setNext(Token token) { _next = token; token.previous = this; return token; } @override String toString() => lexeme; } /** * The enumeration `TokenType` defines the types of tokens that can be returned by the * scanner. */ class TokenType extends Enum<TokenType> { /** * The type of the token that marks the end of the input. */ static const TokenType EOF = const TokenType_EOF('EOF', 0, ""); static const TokenType EQ = const TokenType('EQ', 1, "="); static const TokenType GT = const TokenType('GT', 2, ">"); static const TokenType LT_SLASH = const TokenType('LT_SLASH', 3, "</"); static const TokenType LT = const TokenType('LT', 4, "<"); static const TokenType SLASH_GT = const TokenType('SLASH_GT', 5, "/>"); static const TokenType COMMENT = const TokenType('COMMENT', 6, null); static const TokenType DECLARATION = const TokenType('DECLARATION', 7, null); static const TokenType DIRECTIVE = const TokenType('DIRECTIVE', 8, null); static const TokenType STRING = const TokenType('STRING', 9, null); static const TokenType TAG = const TokenType('TAG', 10, null); static const TokenType TEXT = const TokenType('TEXT', 11, null); static const List<TokenType> values = const [ EOF, EQ, GT, LT_SLASH, LT, SLASH_GT, COMMENT, DECLARATION, DIRECTIVE, STRING, TAG, TEXT ]; /** * The lexeme that defines this type of token, or `null` if there is more than one possible * lexeme for this type of token. */ final String lexeme; const TokenType(String name, int ordinal, this.lexeme) : super(name, ordinal); } class TokenType_EOF extends TokenType { const TokenType_EOF(String name, int ordinal, String arg0) : super(name, ordinal, arg0); @override String toString() => "-eof-"; } /** * Instances of the class `ToSourceVisitor` write a source representation of a visited XML * node (and all of it's children) to a writer. */ class ToSourceVisitor implements XmlVisitor<Object> { /** * The writer to which the source is to be written. */ final PrintWriter _writer; /** * Initialize a newly created visitor to write source code representing the visited nodes to the * given writer. * * @param writer the writer to which the source is to be written */ ToSourceVisitor(this._writer); @override Object visitHtmlScriptTagNode(HtmlScriptTagNode node) => visitXmlTagNode(node); @override Object visitHtmlUnit(HtmlUnit node) { for (XmlTagNode child in node.tagNodes) { _visit(child); } return null; } @override Object visitXmlAttributeNode(XmlAttributeNode node) { String name = node.name; Token value = node.valueToken; if (name.length == 0) { _writer.print("__"); } else { _writer.print(name); } _writer.print("="); if (value == null) { _writer.print("__"); } else { _writer.print(value.lexeme); } return null; } @override Object visitXmlTagNode(XmlTagNode node) { _writer.print("<"); String tagName = node.tag; _writer.print(tagName); for (XmlAttributeNode attribute in node.attributes) { _writer.print(" "); _visit(attribute); } _writer.print(node.attributeEnd.lexeme); if (node.closingTag != null) { for (XmlTagNode child in node.tagNodes) { _visit(child); } _writer.print("</"); _writer.print(tagName); _writer.print(">"); } return null; } /** * Safely visit the given node. * * @param node the node to be visited */ void _visit(XmlNode node) { if (node != null) { node.accept(this); } } } /** * Instances of `XmlAttributeNode` represent name/value pairs owned by an [XmlTagNode]. */ class XmlAttributeNode extends XmlNode { /** * An empty list of XML attribute nodes. */ static const List<XmlAttributeNode> EMPTY_LIST = const <XmlAttributeNode>[]; final Token _name; final Token equals; final Token _value; List<XmlExpression> expressions = XmlExpression.EMPTY_ARRAY; /** * Construct a new instance representing an XML attribute. * * @param name the name token (not `null`). This may be a zero length token if the attribute * is badly formed. * @param equals the equals sign or `null` if none * @param value the value token (not `null`) */ XmlAttributeNode(this._name, this.equals, this._value); @override Token get beginToken => _name; @override Token get endToken => _value; /** * Answer the attribute name. This may be a zero length string if the attribute is badly formed. * * @return the name (not `null`) */ String get name => _name.lexeme; /** * Answer the attribute name token. This may be a zero length token if the attribute is badly * formed. * * @return the name token (not `null`) */ Token get nameToken => _name; /** * Answer the lexeme for the value token without the leading and trailing quotes. * * @return the text or `null` if the value is not specified */ String get text { if (_value == null) { return null; } //TODO (danrubel): replace HTML character encodings with the actual // characters String text = _value.lexeme; int len = text.length; if (len > 0) { if (text.codeUnitAt(0) == 0x22) { if (len > 1 && text.codeUnitAt(len - 1) == 0x22) { return text.substring(1, len - 1); } else { return text.substring(1); } } else if (text.codeUnitAt(0) == 0x27) { if (len > 1 && text.codeUnitAt(len - 1) == 0x27) { return text.substring(1, len - 1); } else { return text.substring(1); } } } return text; } /** * Answer the offset of the value after the leading quote. * * @return the offset of the value, or `-1` if the value is not specified */ int get textOffset { if (_value == null) { return -1; } String text = _value.lexeme; if (StringUtilities.startsWithChar(text, 0x22) || StringUtilities.startsWithChar(text, 0x27)) { return _value.offset + 1; } return _value.offset; } /** * Answer the attribute value token. A properly formed value will start and end with matching * quote characters, but the value returned may not be properly formed. * * @return the value token or `null` if this represents a badly formed attribute */ Token get valueToken => _value; @override accept(XmlVisitor visitor) => visitor.visitXmlAttributeNode(this); @override void visitChildren(XmlVisitor visitor) { // no children to visit } } /** * Instances of the class `XmlExpression` represent an abstract expression embedded into * [XmlNode]. */ abstract class XmlExpression { /** * An empty list of expressions. */ static const List<XmlExpression> EMPTY_ARRAY = const <XmlExpression>[]; /** * Return the offset of the character immediately following the last character of this * expression's source range. This is equivalent to `getOffset() + getLength()`. * * @return the offset of the character just past the expression's source range */ int get end; /** * Return the number of characters in the expression's source range. */ int get length; /** * Return the offset of the first character in the expression's source range. */ int get offset; /** * Check if the given offset belongs to the expression's source range. */ bool contains(int offset) => this.offset <= offset && offset < end; /** * Return the [Reference] at the given offset. * * @param offset the offset from the beginning of the file * @return the [Reference] at the given offset, maybe `null` */ XmlExpression_Reference getReference(int offset); } /** * The reference to the [Element]. */ class XmlExpression_Reference { Element element; int offset = 0; int length = 0; XmlExpression_Reference(Element element, int offset, int length) { this.element = element; this.offset = offset; this.length = length; } } /** * The abstract class `XmlNode` defines behavior common to all XML/HTML nodes. */ abstract class XmlNode { /** * The parent of the node, or `null` if the node is the root of an AST structure. */ XmlNode _parent; /** * The element associated with this node or `null` if the receiver is not resolved. */ Element _element; /** * Return the first token included in this node's source range. * * @return the first token or `null` if none */ Token get beginToken; /** * Return the element associated with this node. * * @return the element or `null` if the receiver is not resolved */ Element get element => _element; /** * Set the element associated with this node. * * @param element the element */ void set element(Element element) { this._element = element; } /** * Return the offset of the character immediately following the last character of this node's * source range. This is equivalent to `node.getOffset() + node.getLength()`. For an html * unit this will be equal to the length of the unit's source. * * @return the offset of the character just past the node's source range */ int get end => offset + length; /** * Return the last token included in this node's source range. * * @return the last token or `null` if none */ Token get endToken; /** * Return the number of characters in the node's source range. * * @return the number of characters in the node's source range */ int get length { Token beginToken = this.beginToken; Token endToken = this.endToken; if (beginToken == null || endToken == null) { return -1; } return endToken.offset + endToken.length - beginToken.offset; } /** * Return the offset from the beginning of the file to the first character in the node's source * range. * * @return the offset from the beginning of the file to the first character in the node's source * range */ int get offset { Token beginToken = this.beginToken; if (beginToken == null) { return -1; } return this.beginToken.offset; } /** * Return this node's parent node, or `null` if this node is the root of an AST structure. * * Note that the relationship between an AST node and its parent node may change over the lifetime * of a node. * * @return the parent of this node, or `null` if none */ XmlNode get parent => _parent; /** * Set the parent of this node to the given node. * * @param newParent the node that is to be made the parent of this node */ void set parent(XmlNode newParent) { XmlNode current = newParent; while (current != null) { if (identical(current, this)) { AnalysisEngine.instance.logger.logError( "Circular structure while setting an XML node's parent", new CaughtException( new ArgumentError(_buildRecursiveStructureMessage(newParent)), null)); return; } current = current.parent; } _parent = newParent; } /** * Use the given visitor to visit this node. * * @param visitor the visitor that will visit this node * @return the value returned by the visitor as a result of visiting this node */ accept(XmlVisitor visitor); /** * Make this node the parent of the given child node. * * @param child the node that will become a child of this node * @return the node that was made a child of this node */ XmlNode becomeParentOf(XmlNode child) { if (child != null) { XmlNode node = child; node.parent = this; } return child; } /** * Make this node the parent of the given child nodes. * * @param children the nodes that will become the children of this node * @param ifEmpty the (empty) nodes to return if "children" is empty * @return the nodes that were made children of this node */ List becomeParentOfAll(List children, {List ifEmpty}) { if (children == null || children.isEmpty) { if (ifEmpty != null) { return ifEmpty; } } if (children != null) { children.forEach((XmlNode node) { node.parent = this; }); } return children; } @override String toString() { PrintStringWriter writer = new PrintStringWriter(); accept(new ToSourceVisitor(writer)); return writer.toString(); } /** * Use the given visitor to visit all of the children of this node. The children will be visited * in source order. * * @param visitor the visitor that will be used to visit the children of this node */ void visitChildren(XmlVisitor visitor); /** * This method exists for debugging purposes only. */ void _appendIdentifier(StringBuffer buffer, XmlNode node) { if (node is XmlTagNode) { buffer.write(node.tag); } else if (node is XmlAttributeNode) { buffer.write(node.name); } else { buffer.write("htmlUnit"); } } /** * This method exists for debugging purposes only. */ String _buildRecursiveStructureMessage(XmlNode newParent) { StringBuffer buffer = new StringBuffer(); buffer.write("Attempt to create recursive structure: "); XmlNode current = newParent; while (current != null) { if (!identical(current, newParent)) { buffer.write(" -> "); } if (identical(current, this)) { buffer.writeCharCode(0x2A); _appendIdentifier(buffer, current); buffer.writeCharCode(0x2A); } else { _appendIdentifier(buffer, current); } current = current.parent; } return buffer.toString(); } } /** * Instances of the class `XmlParser` are used to parse tokens into a AST structure comprised * of [XmlNode]s. */ class XmlParser { /** * The source being parsed. */ final Source source; /** * The next token to be parsed. */ Token _currentToken; /** * Construct a parser for the specified source. * * @param source the source being parsed */ XmlParser(this.source); /** * Answer the current token. * * @return the current token */ Token get currentToken => _currentToken; /** * Create a node representing an attribute. * * @param name the name of the attribute * @param equals the equals sign, or `null` if there is no value * @param value the value of the attribute * @return the node that was created */ XmlAttributeNode createAttributeNode(Token name, Token equals, Token value) => new XmlAttributeNode(name, equals, value); /** * Create a node representing a tag. * * @param nodeStart the token marking the beginning of the tag * @param tag the name of the tag * @param attributes the attributes in the tag * @param attributeEnd the token terminating the region where attributes can be * @param tagNodes the children of the tag * @param contentEnd the token that starts the closing tag * @param closingTag the name of the tag that occurs in the closing tag * @param nodeEnd the last token in the tag * @return the node that was created */ XmlTagNode createTagNode(Token nodeStart, Token tag, List<XmlAttributeNode> attributes, Token attributeEnd, List<XmlTagNode> tagNodes, Token contentEnd, Token closingTag, Token nodeEnd) => new XmlTagNode(nodeStart, tag, attributes, attributeEnd, tagNodes, contentEnd, closingTag, nodeEnd); /** * Answer `true` if the specified tag is self closing and thus should never have content or * child tag nodes. * * @param tag the tag (not `null`) * @return `true` if self closing */ bool isSelfClosing(Token tag) => false; /** * Parse the entire token stream and in the process, advance the current token to the end of the * token stream. * * @return the list of tag nodes found (not `null`, contains no `null`) */ List<XmlTagNode> parseTopTagNodes(Token firstToken) { _currentToken = firstToken; List<XmlTagNode> tagNodes = new List<XmlTagNode>(); TokenType type = _currentToken.type; while (type != TokenType.EOF) { if (type == TokenType.LT) { tagNodes.add(_parseTagNode()); } else if (type == TokenType.DECLARATION || type == TokenType.DIRECTIVE || type == TokenType.COMMENT) { // ignored tokens _currentToken = _currentToken.next; } else { _reportUnexpectedToken(); _currentToken = _currentToken.next; } type = _currentToken.type; } return tagNodes; } /** * Insert a synthetic token of the specified type before the current token * * @param type the type of token to be inserted (not `null`) * @return the synthetic token that was inserted (not `null`) */ Token _insertSyntheticToken(TokenType type) { Token token = new Token.con2(type, _currentToken.offset, ""); _currentToken.previous.setNext(token); token.setNext(_currentToken); return token; } /** * Parse the token stream for an attribute. This method advances the current token over the * attribute, but should not be called if the [currentToken] is not [TokenType.TAG]. * * @return the attribute (not `null`) */ XmlAttributeNode _parseAttribute() { // Assume the current token is a tag Token name = _currentToken; _currentToken = _currentToken.next; // Equals sign Token equals; if (_currentToken.type == TokenType.EQ) { equals = _currentToken; _currentToken = _currentToken.next; } else { _reportUnexpectedToken(); equals = _insertSyntheticToken(TokenType.EQ); } // String value Token value; if (_currentToken.type == TokenType.STRING) { value = _currentToken; _currentToken = _currentToken.next; } else { _reportUnexpectedToken(); value = _insertSyntheticToken(TokenType.STRING); } return createAttributeNode(name, equals, value); } /** * Parse the stream for a sequence of attributes. This method advances the current token to the * next [TokenType.GT], [TokenType.SLASH_GT], or [TokenType.EOF]. * * @return a collection of zero or more attributes (not `null`, contains no `null`s) */ List<XmlAttributeNode> _parseAttributes() { TokenType type = _currentToken.type; if (type == TokenType.GT || type == TokenType.SLASH_GT || type == TokenType.EOF) { return XmlTagNode.NO_ATTRIBUTES; } List<XmlAttributeNode> attributes = new List<XmlAttributeNode>(); while (type != TokenType.GT && type != TokenType.SLASH_GT && type != TokenType.EOF) { if (type == TokenType.TAG) { attributes.add(_parseAttribute()); } else { _reportUnexpectedToken(); _currentToken = _currentToken.next; } type = _currentToken.type; } return attributes; } /** * Parse the stream for a sequence of tag nodes existing within a parent tag node. This method * advances the current token to the next [TokenType.LT_SLASH] or [TokenType.EOF]. * * @return a list of nodes (not `null`, contains no `null`s) */ List<XmlTagNode> _parseChildTagNodes() { TokenType type = _currentToken.type; if (type == TokenType.LT_SLASH || type == TokenType.EOF) { return XmlTagNode.NO_TAG_NODES; } List<XmlTagNode> nodes = new List<XmlTagNode>(); while (type != TokenType.LT_SLASH && type != TokenType.EOF) { if (type == TokenType.LT) { nodes.add(_parseTagNode()); } else if (type == TokenType.COMMENT) { // ignored token _currentToken = _currentToken.next; } else { _reportUnexpectedToken(); _currentToken = _currentToken.next; } type = _currentToken.type; } return nodes; } /** * Parse the token stream for the next tag node. This method advances current token over the * parsed tag node, but should only be called if the current token is [TokenType.LT] * * @return the tag node or `null` if none found */ XmlTagNode _parseTagNode() { // Assume that the current node is a tag node start TokenType.LT Token nodeStart = _currentToken; _currentToken = _currentToken.next; // Get the tag or create a synthetic tag and report an error Token tag; if (_currentToken.type == TokenType.TAG) { tag = _currentToken; _currentToken = _currentToken.next; } else { _reportUnexpectedToken(); tag = _insertSyntheticToken(TokenType.TAG); } // Parse the attributes List<XmlAttributeNode> attributes = _parseAttributes(); // Token ending attribute list Token attributeEnd; if (_currentToken.type == TokenType.GT || _currentToken.type == TokenType.SLASH_GT) { attributeEnd = _currentToken; _currentToken = _currentToken.next; } else { _reportUnexpectedToken(); attributeEnd = _insertSyntheticToken(TokenType.SLASH_GT); } // If the node has no children, then return the node if (attributeEnd.type == TokenType.SLASH_GT || isSelfClosing(tag)) { return createTagNode(nodeStart, tag, attributes, attributeEnd, XmlTagNode.NO_TAG_NODES, _currentToken, null, attributeEnd); } // Parse the child tag nodes List<XmlTagNode> tagNodes = _parseChildTagNodes(); // Token ending child tag nodes Token contentEnd; if (_currentToken.type == TokenType.LT_SLASH) { contentEnd = _currentToken; _currentToken = _currentToken.next; } else { // TODO (danrubel): handle self closing HTML elements by inserting // synthetic tokens but not reporting an error _reportUnexpectedToken(); contentEnd = _insertSyntheticToken(TokenType.LT_SLASH); } // Closing tag Token closingTag; if (_currentToken.type == TokenType.TAG) { closingTag = _currentToken; _currentToken = _currentToken.next; } else { _reportUnexpectedToken(); closingTag = _insertSyntheticToken(TokenType.TAG); } // Token ending node Token nodeEnd; if (_currentToken.type == TokenType.GT) { nodeEnd = _currentToken; _currentToken = _currentToken.next; } else { _reportUnexpectedToken(); nodeEnd = _insertSyntheticToken(TokenType.GT); } return createTagNode(nodeStart, tag, attributes, attributeEnd, tagNodes, contentEnd, closingTag, nodeEnd); } /** * Report the current token as unexpected */ void _reportUnexpectedToken() { // TODO (danrubel): report unexpected token } } /** * Instances of `XmlTagNode` represent XML or HTML elements such as `` and * `<body foo="bar"> ... </body>`. */ class XmlTagNode extends XmlNode { /** * Constant representing empty list of attributes. */ static List<XmlAttributeNode> NO_ATTRIBUTES = new UnmodifiableListView(new List<XmlAttributeNode>()); /** * Constant representing empty list of tag nodes. */ static List<XmlTagNode> NO_TAG_NODES = new UnmodifiableListView(new List<XmlTagNode>()); /** * The starting [TokenType.LT] token (not `null`). */ final Token nodeStart; /** * The [TokenType.TAG] token after the starting '<' (not `null`). */ final Token _tag; /** * The attributes contained by the receiver (not `null`, contains no `null`s). */ List<XmlAttributeNode> _attributes; /** * The [TokenType.GT] or [TokenType.SLASH_GT] token after the attributes (not * `null`). The token may be the same token as [nodeEnd] if there are no child * [tagNodes]. */ final Token attributeEnd; /** * The tag nodes contained in the receiver (not `null`, contains no `null`s). */ List<XmlTagNode> _tagNodes; /** * The token (not `null`) after the content, which may be * * (1) [TokenType.LT_SLASH] for nodes with open and close tags, or * * (2) the [TokenType.LT] nodeStart of the next sibling node if this node is self * closing or the attributeEnd is [TokenType.SLASH_GT], or * * (3) [TokenType.EOF] if the node does not have a closing tag and is the last node in * the stream [TokenType.LT_SLASH] token after the content, or `null` if there is no * content and the attributes ended with [TokenType.SLASH_GT]. */ final Token contentEnd; /** * The closing [TokenType.TAG] after the child elements or `null` if there is no * content and the attributes ended with [TokenType.SLASH_GT] */ final Token closingTag; /** * The ending [TokenType.GT] or [TokenType.SLASH_GT] token (not `null`). */ final Token nodeEnd; /** * The expressions that are embedded in the tag's content. */ List<XmlExpression> expressions = XmlExpression.EMPTY_ARRAY; /** * Construct a new instance representing an XML or HTML element * * @param nodeStart the starting [TokenType.LT] token (not `null`) * @param tag the [TokenType.TAG] token after the starting '<' (not `null`). * @param attributes the attributes associated with this element or [NO_ATTRIBUTES] (not * `null`, contains no `null`s) * @param attributeEnd The [TokenType.GT] or [TokenType.SLASH_GT] token after the * attributes (not `null`). The token may be the same token as [nodeEnd] if * there are no child [tagNodes]. * @param tagNodes child tag nodes of the receiver or [NO_TAG_NODES] (not `null`, * contains no `null`s) * @param contentEnd the token (not `null`) after the content, which may be * * (1) [TokenType.LT_SLASH] for nodes with open and close tags, or * * (2) the [TokenType.LT] nodeStart of the next sibling node if this node is * self closing or the attributeEnd is [TokenType.SLASH_GT], or * * (3) [TokenType.EOF] if the node does not have a closing tag and is the last * node in the stream [TokenType.LT_SLASH] token after the content, or `null` * if there is no content and the attributes ended with [TokenType.SLASH_GT]. * @param closingTag the closing [TokenType.TAG] after the child elements or `null` if * there is no content and the attributes ended with [TokenType.SLASH_GT] * @param nodeEnd the ending [TokenType.GT] or [TokenType.SLASH_GT] token (not * `null`) */ XmlTagNode(this.nodeStart, this._tag, List<XmlAttributeNode> attributes, this.attributeEnd, List<XmlTagNode> tagNodes, this.contentEnd, this.closingTag, this.nodeEnd) { this._attributes = becomeParentOfAll(attributes, ifEmpty: NO_ATTRIBUTES); this._tagNodes = becomeParentOfAll(tagNodes, ifEmpty: NO_TAG_NODES); } /** * Answer the receiver's attributes. Callers should not manipulate the returned list to edit the * AST structure. * * @return the attributes (not `null`, contains no `null`s) */ List<XmlAttributeNode> get attributes => _attributes; @override Token get beginToken => nodeStart; /** * Return a string representing the content contained in the receiver. This * includes the textual representation of any child tag nodes ([getTagNodes]). * Whitespace between '<', '</', and '>', '/>' is discarded, but all * other whitespace is preserved. */ String get content { Token token = attributeEnd.next; if (identical(token, contentEnd)) { return ""; } // TODO(danrubel) Handle CDATA and replace HTML character encodings with // the actual characters. String content = token.lexeme; token = token.next; if (identical(token, contentEnd)) { return content; } StringBuffer buffer = new StringBuffer(); buffer.write(content); while (!identical(token, contentEnd)) { buffer.write(token.lexeme); token = token.next; } return buffer.toString(); } @override Token get endToken { if (nodeEnd != null) { return nodeEnd; } if (closingTag != null) { return closingTag; } if (contentEnd != null) { return contentEnd; } if (!_tagNodes.isEmpty) { return _tagNodes[_tagNodes.length - 1].endToken; } if (attributeEnd != null) { return attributeEnd; } if (!_attributes.isEmpty) { return _attributes[_attributes.length - 1].endToken; } return _tag; } /** * Answer the tag name after the starting '<'. * * @return the tag name (not `null`) */ String get tag => _tag.lexeme; /** * Answer the tag nodes contained in the receiver. Callers should not manipulate the returned list * to edit the AST structure. * * @return the children (not `null`, contains no `null`s) */ List<XmlTagNode> get tagNodes => _tagNodes; /** * Answer the [TokenType.TAG] token after the starting '<'. * * @return the token (not `null`) */ Token get tagToken => _tag; @override accept(XmlVisitor visitor) => visitor.visitXmlTagNode(this); /** * Answer the attribute with the specified name. * * @param name the attribute name * @return the attribute or `null` if no matching attribute is found */ XmlAttributeNode getAttribute(String name) { for (XmlAttributeNode attribute in _attributes) { if (attribute.name == name) { return attribute; } } return null; } /** * Find the attribute with the given name (see [getAttribute] and answer the lexeme * for the attribute's value token without the leading and trailing quotes (see * [XmlAttributeNode.getText]). * * @param name the attribute name * @return the attribute text or `null` if no matching attribute is found */ String getAttributeText(String name) { XmlAttributeNode attribute = getAttribute(name); return attribute != null ? attribute.text : null; } @override void visitChildren(XmlVisitor visitor) { for (XmlAttributeNode node in _attributes) { node.accept(visitor); } for (XmlTagNode node in _tagNodes) { node.accept(visitor); } } } /** * The interface `XmlVisitor` defines the behavior of objects that can be used to visit an * [XmlNode] structure. */ abstract class XmlVisitor<R> { R visitHtmlScriptTagNode(HtmlScriptTagNode node); R visitHtmlUnit(HtmlUnit htmlUnit); R visitXmlAttributeNode(XmlAttributeNode xmlAttributeNode); R visitXmlTagNode(XmlTagNode xmlTagNode); }