pkg/csslib/lib/parser.dart - Issue 751453004: Improve the speed and memory efficiency of csslib parsing.

Unified Diff: pkg/csslib/lib/parser.dart

Issue 751453004: Improve the speed and memory efficiency of csslib parsing. (Closed) Base URL: https://dart.googlecode.com/svn/branches/bleeding_edge/dart

Patch Set: Created 6 years, 1 month ago

Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.

Jump to:

View side-by-side diff with in-line comments

Download patch

Index: pkg/csslib/lib/parser.dart

diff --git a/pkg/csslib/lib/parser.dart b/pkg/csslib/lib/parser.dart

index 282fe591c49488fb20803cf9ffbf8dad8a4cd827..6060166944ec8d7fdbf5e4e16846840eee9fd1e0 100644

--- a/pkg/csslib/lib/parser.dart

+++ b/pkg/csslib/lib/parser.dart

@@ -196,7 +196,7 @@ class _Parser {

StyleSheet parse() {

List<TreeNode> productions = [];

- int start = _peekToken.start;

+ var start = _peekToken.span;

while (!_maybeEat(TokenKind.END_OF_FILE) && !_peekKind(TokenKind.RBRACE)) {

// TODO(terry): Need to handle charset.

var directive = processDirective();

@@ -222,7 +222,7 @@ class _Parser {

StyleSheet parseSelector() {

List<TreeNode> productions = [];

- int start = _peekToken.start;

+ var start = _peekToken.span;

while (!_maybeEat(TokenKind.END_OF_FILE) && !_peekKind(TokenKind.RBRACE)) {

var selector = processSelector();

if (selector != null) {

@@ -334,12 +334,14 @@ class _Parser {

messages.warning(message, location);

}

- SourceSpan _makeSpan(int start) {

+ SourceSpan _makeSpan(FileSpan start) {

// TODO(terry): there are places where we are creating spans before we eat

- // the tokens, so using _previousToken.end is not always valid.

- var end = _previousToken != null && _previousToken.end >= start

- ? _previousToken.end : _peekToken.end;

- return file.span(start, end);

+ // the tokens, so using _previousToken is not always valid.

+ // TODO(nweiz): use < rather than compareTo when SourceSpan supports it.

+ if (_previousToken == null || _previousToken.span.compareTo(start) < 0) {

+ return start;

+ }

+ return start.expand(_previousToken.span);

}

///////////////////////////////////////////////////////////////////

@@ -389,7 +391,7 @@ class _Parser {

// Grammar: [ONLY | NOT]? S* media_type S*

// [ AND S* MediaExpr ]* | MediaExpr [ AND S* MediaExpr ]*

- int start = _peekToken.start;

+ var start = _peekToken.span;

// Is it a unary media operator?

var op = _peekToken.text;

@@ -408,7 +410,7 @@ class _Parser {

}

_next();

- start = _peekToken.start;

+ start = _peekToken.span;

}

var type;

@@ -441,14 +443,14 @@ class _Parser {

}

MediaExpression processMediaExpression([bool andOperator = false]) {

- int start = _peekToken.start;

+ var start = _peekToken.span;

// Grammar: '(' S* media_feature S* [ ':' S* expr ]? ')' S*

if (_maybeEat(TokenKind.LPAREN)) {

if (_peekIdentifier()) {

var feature = identifier(); // Media feature.

while (_maybeEat(TokenKind.COLON)) {

- int startExpr = _peekToken.start;

+ var startExpr = _peekToken.span;

var exprs = processExpr();

if (_maybeEat(TokenKind.RPAREN)) {

return new MediaExpression(andOperator, feature, exprs,

@@ -484,7 +486,7 @@ class _Parser {

* content '@content'

processDirective() {

- int start = _peekToken.start;

+ var start = _peekToken.span;

var tokId = processVariableOrDirective();

if (tokId is VarDefinitionDirective) return tokId;

@@ -703,7 +705,7 @@ class _Parser {

List<TreeNode> productions = [];

- start = _peekToken.start;

+ start = _peekToken.span;

while (!_maybeEat(TokenKind.END_OF_FILE)) {

RuleSet ruleset = processRuleSet();

if (ruleset == null) {

@@ -755,7 +757,7 @@ class _Parser {

namespaceUri, _makeSpan(start));

case TokenKind.DIRECTIVE_MIXIN:

- return processMixin(start);

+ return processMixin();

case TokenKind.DIRECTIVE_INCLUDE:

return processInclude( _makeSpan(start));

@@ -778,7 +780,7 @@ class _Parser {

* [ruleset | property | directive]*

* '}'

- MixinDefinition processMixin(int start) {

+ MixinDefinition processMixin() {

_next();

var name = identifier();

@@ -793,7 +795,7 @@ class _Parser {

if (varDef is VarDefinitionDirective || varDef is VarDefinition) {

params.add(varDef);

} else if (mustHaveParam) {

- _warning("Expecting parameter", _makeSpan(_peekToken.start));

+ _warning("Expecting parameter", _makeSpan(_peekToken.span));

keepGoing = false;

}

if (_maybeEat(TokenKind.COMMA)) {

@@ -810,7 +812,7 @@ class _Parser {

List<TreeNode> declarations = [];

var mixinDirective;

- start = _peekToken.start;

+ var start = _peekToken.span;

while (!_maybeEat(TokenKind.END_OF_FILE)) {

var directive = processDirective();

if (directive != null) {

@@ -833,7 +835,7 @@ class _Parser {

include.span));

} else {

_warning("Error mixing of top-level vs declarations mixins",

- _makeSpan(include));

+ _makeSpan(include.span));

}

});

declGroup.declarations.insertAll(0, newDecls);

@@ -882,7 +884,7 @@ class _Parser {

* return the token id of a directive or -1 if neither.

processVariableOrDirective({bool mixinParameter: false}) {

- int start = _peekToken.start;

+ var start = _peekToken.span;

var tokId = _peek();

// Handle case for @ directive (where there's a whitespace between the @

@@ -1046,7 +1048,7 @@ class _Parser {

}

DeclarationGroup processDeclarations({bool checkBrace: true}) {

- int start = _peekToken.start;

+ var start = _peekToken.span;

if (checkBrace) _eat(TokenKind.LBRACE);

@@ -1104,7 +1106,7 @@ class _Parser {

List<DeclarationGroup> processMarginsDeclarations() {

List groups = [];

- int start = _peekToken.start;

+ var start = _peekToken.span;

_eat(TokenKind.LBRACE);

@@ -1189,7 +1191,7 @@ class _Parser {

SelectorGroup processSelectorGroup() {

List<Selector> selectors = [];

- int start = _peekToken.start;

+ var start = _peekToken.span;

do {

Selector selector = processSelector();

@@ -1208,7 +1210,7 @@ class _Parser {

Selector processSelector() {

var simpleSequences = <SimpleSelectorSequence>[];

- var start = _peekToken.start;

+ var start = _peekToken.span;

while (true) {

// First item is never descendant make sure it's COMBINATOR_NONE.

var selectorItem = simpleSelectorSequence(simpleSequences.length == 0);

@@ -1225,7 +1227,7 @@ class _Parser {

}

simpleSelectorSequence(bool forceCombinatorNone) {

- var start = _peekToken.start;

+ var start = _peekToken.span;

var combinatorType = TokenKind.COMBINATOR_NONE;

var thisOperator = false;

@@ -1301,12 +1303,12 @@ class _Parser {

// code.

// TODO(terry): Need to handle attribute namespace too.

var first;

- int start = _peekToken.start;

+ var start = _peekToken.span;

switch (_peek()) {

case TokenKind.ASTERISK:

// Mark as universal namespace.

var tok = _next();

- first = new Wildcard(_makeSpan(tok.start));

+ first = new Wildcard(_makeSpan(tok.span));

break;

case TokenKind.IDENTIFIER:

first = identifier();

@@ -1329,7 +1331,7 @@ class _Parser {

case TokenKind.ASTERISK:

// Mark as universal element

var tok = _next();

- element = new Wildcard(_makeSpan(tok.start));

+ element = new Wildcard(_makeSpan(tok.span));

break;

case TokenKind.IDENTIFIER:

element = identifier();

@@ -1366,7 +1368,7 @@ class _Parser {

simpleSelectorTail() {

// Check for HASH | class | attrib | pseudo | negation

- var start = _peekToken.start;

+ var start = _peekToken.span;

switch (_peek()) {

case TokenKind.HASH:

_eat(TokenKind.HASH);

@@ -1413,7 +1415,7 @@ class _Parser {

}

- processPseudoSelector(int start) {

+ processPseudoSelector(FileSpan start) {

// :pseudo-class ::pseudo-element

// TODO(terry): '::' should be token.

_eat(TokenKind.COLON);

@@ -1492,7 +1494,7 @@ class _Parser {

* NUMBER {num}

processSelectorExpression() {

- var start = _peekToken.start;

+ var start = _peekToken.span;

var expressions = [];

@@ -1503,12 +1505,12 @@ class _Parser {

while (keepParsing) {

switch (_peek()) {

case TokenKind.PLUS:

- start = _peekToken.start;

+ start = _peekToken.span;

termToken = _next();

expressions.add(new OperatorPlus(_makeSpan(start)));

break;

case TokenKind.MINUS:

- start = _peekToken.start;

+ start = _peekToken.span;

termToken = _next();

expressions.add(new OperatorMinus(_makeSpan(start)));

break;

@@ -1573,7 +1575,7 @@ class _Parser {

AttributeSelector processAttribute() {

- var start = _peekToken.start;

+ var start = _peekToken.span;

if (_maybeEat(TokenKind.LBRACK)) {

var attrName = identifier();

@@ -1629,7 +1631,7 @@ class _Parser {

Declaration processDeclaration(List dartStyles) {

Declaration decl;

- int start = _peekToken.start;

+ var start = _peekToken.span;

// IE7 hack of * before property name if so the property is IE7 or below.

var ie7 = _peekKind(TokenKind.ASTERISK);

@@ -1681,7 +1683,7 @@ class _Parser {

simpleSequences.add(selector);

}

if (_peekKind(TokenKind.COLON)) {

- var pseudoSelector = processPseudoSelector(_peekToken.start);

+ var pseudoSelector = processPseudoSelector(_peekToken.span);

if (pseudoSelector is PseudoElementSelector ||

pseudoSelector is PseudoClassSelector) {

simpleSequences.add(pseudoSelector);

@@ -2033,7 +2035,7 @@ class _Parser {

// term: (see processTerm)

Expressions processExpr([bool ieFilter = false]) {

- var start = _peekToken.start;

+ var start = _peekToken.span;

var expressions = new Expressions(_makeSpan(start));

var keepGoing = true;

@@ -2041,7 +2043,7 @@ class _Parser {

while (keepGoing && (expr = processTerm(ieFilter)) != null) {

var op;

- var opStart = _peekToken.start;

+ var opStart = _peekToken.span;

switch (_peek()) {

case TokenKind.SLASH:

@@ -2053,7 +2055,7 @@ class _Parser {

case TokenKind.BACKSLASH:

// Backslash outside of string; detected IE8 or older signaled by \9 at

// end of an expression.

- var ie8Start = _peekToken.start;

+ var ie8Start = _peekToken.span;

_next();

if (_peekKind(TokenKind.INTEGER)) {

@@ -2117,7 +2119,7 @@ class _Parser {

// function: IDENT '(' expr ')'

processTerm([bool ieFilter = false]) {

- var start = _peekToken.start;

+ var start = _peekToken.span;

Token t; // token for term's value

var value; // value of term (numeric values)

@@ -2364,7 +2366,7 @@ class _Parser {

}

String processQuotedString([bool urlString = false]) {

- var start = _peekToken.start;

+ var start = _peekToken.span;

// URI term sucks up everything inside of quotes(' or ") or between parens

var stopToken = urlString ? TokenKind.RPAREN : -1;

@@ -2377,19 +2379,19 @@ class _Parser {

switch (_peek()) {

case TokenKind.SINGLE_QUOTE:

stopToken = TokenKind.SINGLE_QUOTE;

- start = _peekToken.start + 1; // Skip the quote might have whitespace.

- _next(); // Skip the SINGLE_QUOTE.

+ _next(); // Skip the SINGLE_QUOTE.

+ start = _peekToken.span;

sra1 2014/12/02 23:43:45 Will the _peekToken always have a span starting im

break;

case TokenKind.DOUBLE_QUOTE:

stopToken = TokenKind.DOUBLE_QUOTE;

- start = _peekToken.start + 1; // Skip the quote might have whitespace.

- _next(); // Skip the DOUBLE_QUOTE.

+ _next(); // Skip the DOUBLE_QUOTE.

+ start = _peekToken.span;

break;

default:

if (urlString) {

if (_peek() == TokenKind.LPAREN) {

_next(); // Skip the LPAREN.

- start = _peekToken.start;

+ start = _peekToken.span;

}

stopToken = TokenKind.RPAREN;

} else {

@@ -2399,8 +2401,6 @@ class _Parser {

}

// Gobble up everything until we hit our stop token.

- var runningStart = _peekToken.start;

var stringValue = new StringBuffer();

while (_peek() != stopToken && _peek() != TokenKind.END_OF_FILE) {

stringValue.write(_next().text);

@@ -2426,7 +2426,7 @@ class _Parser {

* We'll just parse everything after the 'progid:' look for the left paren

* then parse to the right paren ignoring everything in between.

- processIEFilter(int startAfterProgidColon) {

+ processIEFilter(FileSpan startAfterProgidColon) {

var parens = 0;

while (_peek() != TokenKind.END_OF_FILE) {

@@ -2438,7 +2438,7 @@ class _Parser {

case TokenKind.RPAREN:

_eat(TokenKind.RPAREN);

if (--parens == 0) {

- var tok = tokenizer.makeIEFilter(startAfterProgidColon,

+ var tok = tokenizer.makeIEFilter(startAfterProgidColon.start.offset,

_peekToken.start);

return new LiteralTerm(tok.text, tok.text, tok.span);

}

@@ -2454,7 +2454,7 @@ class _Parser {

// function: IDENT '(' expr ')'

processFunction(Identifier func) {

- var start = _peekToken.start;

+ var start = _peekToken.span;

var name = func.name;

@@ -2519,10 +2519,10 @@ class _Parser {

if (isChecked) {

_warning('expected identifier, but found $tok', tok.span);

}

- return new Identifier("", _makeSpan(tok.start));

+ return new Identifier("", _makeSpan(tok.span));

}

- return new Identifier(tok.text, _makeSpan(tok.start));

+ return new Identifier(tok.text, _makeSpan(tok.span));

}

// TODO(terry): Move this to base <= 36 and into shared code.

« no previous file with comments | « pkg/csslib/CHANGELOG.md ('k') | pkg/csslib/lib/src/token.dart » ('j') | no next file with comments »