| Index: packages/analyzer/lib/src/util/fast_uri.dart
|
| diff --git a/packages/analyzer/lib/src/util/fast_uri.dart b/packages/analyzer/lib/src/util/fast_uri.dart
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..40681bdaae7ca21ecad90589b55ef8e265b8316c
|
| --- /dev/null
|
| +++ b/packages/analyzer/lib/src/util/fast_uri.dart
|
| @@ -0,0 +1,324 @@
|
| +// Copyright (c) 2016, 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.
|
| +
|
| +import 'dart:collection';
|
| +
|
| +/**
|
| + * Implementation of [Uri] that understands only a limited set of valid
|
| + * URI formats, but works fast. In practice Dart code almost always uses such
|
| + * limited URI format, so almost always can be processed fast.
|
| + */
|
| +class FastUri implements Uri {
|
| + /***
|
| + * The maximum [_cache] length before we flush it and start a new generation.
|
| + */
|
| + static const int _MAX_CACHE_LENGTH_BEFORE_FLUSH = 50000;
|
| +
|
| + static HashMap<String, Uri> _cache = new HashMap<String, Uri>();
|
| + static int _currentCacheLength = 0;
|
| + static int _currentCacheGeneration = 0;
|
| +
|
| + static bool _hashUsingText = _shouldComputeHashCodeUsingText();
|
| +
|
| + final int _cacheGeneration;
|
| + final String _text;
|
| + final String _scheme;
|
| + final bool _hasEmptyAuthority;
|
| + final String _path;
|
| +
|
| + /**
|
| + * The offset of the last `/` in [_text], or `null` if there isn't any.
|
| + */
|
| + final int _lastSlashIndex;
|
| +
|
| + /**
|
| + * The cached hash code.
|
| + */
|
| + int _hashCode;
|
| +
|
| + Uri _cachedFallbackUri;
|
| +
|
| + FastUri._(this._cacheGeneration, this._text, this._scheme,
|
| + this._hasEmptyAuthority, this._path, this._lastSlashIndex);
|
| +
|
| + @override
|
| + String get authority => '';
|
| +
|
| + @override
|
| + UriData get data => null;
|
| +
|
| + @override
|
| + String get fragment => '';
|
| +
|
| + @override
|
| + bool get hasAbsolutePath => path.startsWith('/');
|
| +
|
| + @override
|
| + bool get hasAuthority => _hasEmptyAuthority;
|
| +
|
| + @override
|
| + bool get hasEmptyPath => _path.isEmpty;
|
| +
|
| + @override
|
| + bool get hasFragment => false;
|
| +
|
| + @override
|
| + int get hashCode {
|
| + return _hashCode ??= _hashUsingText
|
| + ? _computeHashUsingText(this)
|
| + : _computeHashUsingCombine(this);
|
| + }
|
| +
|
| + @override
|
| + bool get hasPort => false;
|
| +
|
| + @override
|
| + bool get hasQuery => false;
|
| +
|
| + @override
|
| + bool get hasScheme => _scheme.isNotEmpty;
|
| +
|
| + @override
|
| + String get host => '';
|
| +
|
| + @override
|
| + bool get isAbsolute => hasScheme;
|
| +
|
| + @override
|
| + String get origin => _fallbackUri.origin;
|
| +
|
| + @override
|
| + String get path => _path;
|
| +
|
| + @override
|
| + List<String> get pathSegments => _fallbackUri.pathSegments;
|
| +
|
| + @override
|
| + int get port => 0;
|
| +
|
| + @override
|
| + String get query => '';
|
| +
|
| + @override
|
| + Map<String, String> get queryParameters => const <String, String>{};
|
| +
|
| + @override
|
| + Map<String, List<String>> get queryParametersAll =>
|
| + const <String, List<String>>{};
|
| +
|
| + @override
|
| + String get scheme => _scheme;
|
| +
|
| + @override
|
| + String get userInfo => '';
|
| +
|
| + /**
|
| + * Full [Uri] object computed on demand; we fall back to this for some of the
|
| + * more complex methods of [Uri] that are less in need of a fast
|
| + * implementation.
|
| + */
|
| + Uri get _fallbackUri => _cachedFallbackUri ??= Uri.parse(_text);
|
| +
|
| + @override
|
| + bool operator ==(other) {
|
| + if (other is FastUri) {
|
| + if (other._cacheGeneration == _cacheGeneration) {
|
| + return identical(other, this);
|
| + }
|
| + return _text == other._text;
|
| + } else if (other is Uri) {
|
| + return _fallbackUri == other;
|
| + }
|
| + return false;
|
| + }
|
| +
|
| + @override
|
| + Uri normalizePath() {
|
| + return this;
|
| + }
|
| +
|
| + @override
|
| + Uri removeFragment() {
|
| + return this;
|
| + }
|
| +
|
| + @override
|
| + Uri replace(
|
| + {String scheme,
|
| + String userInfo,
|
| + String host,
|
| + int port,
|
| + String path,
|
| + Iterable<String> pathSegments,
|
| + String query,
|
| + Map<String, dynamic> queryParameters,
|
| + String fragment}) {
|
| + return _fallbackUri.replace(
|
| + scheme: scheme,
|
| + userInfo: userInfo,
|
| + host: host,
|
| + port: port,
|
| + path: path,
|
| + pathSegments: pathSegments,
|
| + query: query,
|
| + queryParameters: queryParameters,
|
| + fragment: fragment);
|
| + }
|
| +
|
| + @override
|
| + Uri resolve(String reference) {
|
| + // TODO: maybe implement faster
|
| + return _fallbackUri.resolve(reference);
|
| + }
|
| +
|
| + @override
|
| + Uri resolveUri(Uri reference) {
|
| + if (reference.hasScheme) {
|
| + return reference;
|
| + }
|
| + String refPath = reference.path;
|
| + if (refPath.startsWith('./')) {
|
| + refPath = refPath.substring(2);
|
| + }
|
| + if (refPath.startsWith('../') ||
|
| + refPath.contains('/../') ||
|
| + refPath.contains('/./')) {
|
| + Uri slowResult = _fallbackUri.resolveUri(reference);
|
| + return FastUri.parse(slowResult.toString());
|
| + }
|
| + String newText;
|
| + if (_lastSlashIndex != null) {
|
| + newText = _text.substring(0, _lastSlashIndex + 1) + refPath;
|
| + } else {
|
| + newText = _text + '/' + refPath;
|
| + }
|
| + return FastUri.parse(newText);
|
| + }
|
| +
|
| + @override
|
| + String toFilePath({bool windows}) {
|
| + return _fallbackUri.toFilePath(windows: windows);
|
| + }
|
| +
|
| + @override
|
| + String toString() => _text;
|
| +
|
| + /**
|
| + * Parse the given URI [text] and return the corresponding [Uri] instance. If
|
| + * the [text] can be represented as a [FastUri], then it is returned. If the
|
| + * [text] is more complex, then `dart:core` [Uri] is created and returned.
|
| + * This method also performs memoization, so that usually the same instance
|
| + * of [FastUri] or [Uri] is returned for the same [text].
|
| + */
|
| + static Uri parse(String text) {
|
| + Uri uri = _cache[text];
|
| + if (uri == null) {
|
| + uri = _parse(text);
|
| + uri ??= Uri.parse(text);
|
| + _cache[text] = uri;
|
| + _currentCacheLength++;
|
| + // If the cache is too big, start a new generation.
|
| + if (_currentCacheLength > _MAX_CACHE_LENGTH_BEFORE_FLUSH) {
|
| + _cache.clear();
|
| + _currentCacheLength = 0;
|
| + _currentCacheGeneration++;
|
| + }
|
| + }
|
| + return uri;
|
| + }
|
| +
|
| + /**
|
| + * This implementation was used before 'fast-URI' in Dart VM.
|
| + */
|
| + static int _computeHashUsingCombine(FastUri uri) {
|
| + // This code is copied from the standard Uri implementation.
|
| + // It is important that Uri and FastUri generate compatible hashCodes
|
| + // because Uri and FastUri may be used as keys in the same map.
|
| + int combine(part, current) {
|
| + // The sum is truncated to 30 bits to make sure it fits into a Smi.
|
| + return (current * 31 + part.hashCode) & 0x3FFFFFFF;
|
| + }
|
| +
|
| + return combine(
|
| + uri.scheme,
|
| + combine(
|
| + uri.userInfo,
|
| + combine(
|
| + uri.host,
|
| + combine(
|
| + uri.port,
|
| + combine(uri.path,
|
| + combine(uri.query, combine(uri.fragment, 1)))))));
|
| + }
|
| +
|
| + /**
|
| + * This implementation should be used with 'fast-URI' in Dart VM.
|
| + * https://github.com/dart-lang/sdk/commit/afbbbb97cfcd86a64d0ba5dcfe1ab758954adaf4
|
| + */
|
| + static int _computeHashUsingText(FastUri uri) {
|
| + return uri._text.hashCode;
|
| + }
|
| +
|
| + static bool _isAlphabetic(int char) {
|
| + return char >= 'A'.codeUnitAt(0) && char <= 'Z'.codeUnitAt(0) ||
|
| + char >= 'a'.codeUnitAt(0) && char <= 'z'.codeUnitAt(0);
|
| + }
|
| +
|
| + static bool _isDigit(int char) {
|
| + return char >= '0'.codeUnitAt(0) && char <= '9'.codeUnitAt(0);
|
| + }
|
| +
|
| + /**
|
| + * Parse the given [text] into a new [FastUri]. If the [text] uses URI
|
| + * features that are not supported by [FastUri], return `null`.
|
| + */
|
| + static FastUri _parse(String text) {
|
| + int schemeEnd = null;
|
| + int pathStart = 0;
|
| + int lastSlashIndex = null;
|
| + for (int i = 0; i < text.length; i++) {
|
| + int char = text.codeUnitAt(i);
|
| + if (_isAlphabetic(char) ||
|
| + _isDigit(char) ||
|
| + char == '.'.codeUnitAt(0) ||
|
| + char == '-'.codeUnitAt(0) ||
|
| + char == '_'.codeUnitAt(0)) {
|
| + // Valid characters.
|
| + } else if (char == '/'.codeUnitAt(0)) {
|
| + lastSlashIndex = i;
|
| + } else if (char == ':'.codeUnitAt(0)) {
|
| + if (schemeEnd != null) {
|
| + return null;
|
| + }
|
| + schemeEnd = i;
|
| + pathStart = i + 1;
|
| + } else {
|
| + return null;
|
| + }
|
| + }
|
| + String scheme = schemeEnd != null ? text.substring(0, schemeEnd) : '';
|
| + bool hasEmptyAuthority = false;
|
| + String path = text.substring(pathStart);
|
| + if (path.startsWith('//')) {
|
| + hasEmptyAuthority = true;
|
| + path = path.substring(2);
|
| + if (!path.startsWith('/')) {
|
| + return null;
|
| + }
|
| + }
|
| + return new FastUri._(_currentCacheGeneration, text, scheme,
|
| + hasEmptyAuthority, path, lastSlashIndex);
|
| + }
|
| +
|
| + /**
|
| + * Determine whether VM has the text based hash code computation in [Uri],
|
| + * or the old combine style.
|
| + *
|
| + * See https://github.com/dart-lang/sdk/issues/27159 for details.
|
| + */
|
| + static bool _shouldComputeHashCodeUsingText() {
|
| + String text = 'package:foo/foo.dart';
|
| + return Uri.parse(text).hashCode == text.hashCode;
|
| + }
|
| +}
|
|
|