| // Copyright (c) 2015, 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 package_config.packages_file; |
| |
| import "package:charcode/ascii.dart"; |
| |
| import "src/util.dart" show isValidPackageName; |
| |
| /// Parses a `.packages` file into a map from package name to base URI. |
| /// |
| /// The [source] is the byte content of a `.packages` file, assumed to be |
| /// UTF-8 encoded. In practice, all significant parts of the file must be ASCII, |
| /// so Latin-1 or Windows-1252 encoding will also work fine. |
| /// |
| /// If the file content is available as a string, its [String.codeUnits] can |
| /// be used as the `source` argument of this function. |
| /// |
| /// The [baseLocation] is used as a base URI to resolve all relative |
| /// URI references against. |
| /// If the content was read from a file, `baseLocation` should be the |
| /// location of that file. |
| /// |
| /// Returns a simple mapping from package name to package location. |
| Map<String, Uri> parse(List<int> source, Uri baseLocation) { |
| int index = 0; |
| Map<String, Uri> result = <String, Uri>{}; |
| while (index < source.length) { |
| bool isComment = false; |
| int start = index; |
| int separatorIndex = -1; |
| int end = source.length; |
| int char = source[index++]; |
| if (char == $cr || char == $lf) { |
| continue; |
| } |
| if (char == $colon) { |
| throw new FormatException("Missing package name", source, index - 1); |
| } |
| isComment = char == $hash; |
| while (index < source.length) { |
| char = source[index++]; |
| if (char == $colon && separatorIndex < 0) { |
| separatorIndex = index - 1; |
| } else if (char == $cr || char == $lf) { |
| end = index - 1; |
| break; |
| } |
| } |
| if (isComment) continue; |
| if (separatorIndex < 0) { |
| throw new FormatException("No ':' on line", source, index - 1); |
| } |
| var packageName = new String.fromCharCodes(source, start, separatorIndex); |
| if (!isValidPackageName(packageName)) { |
| throw new FormatException("Not a valid package name", packageName, 0); |
| } |
| var packageUri = new String.fromCharCodes(source, separatorIndex + 1, end); |
| var packageLocation = Uri.parse(packageUri); |
| packageLocation = baseLocation.resolveUri(packageLocation); |
| if (!packageLocation.path.endsWith('/')) { |
| packageLocation = |
| packageLocation.replace(path: packageLocation.path + "/"); |
| } |
| if (result.containsKey(packageName)) { |
| throw new FormatException( |
| "Same package name occured twice.", source, start); |
| } |
| result[packageName] = packageLocation; |
| } |
| return result; |
| } |
| |
| /// Writes the mapping to a [StringSink]. |
| /// |
| /// If [comment] is provided, the output will contain this comment |
| /// with `# ` in front of each line. |
| /// Lines are defined as ending in line feed (`'\n'`). If the final |
| /// line of the comment doesn't end in a line feed, one will be added. |
| /// |
| /// If [baseUri] is provided, package locations will be made relative |
| /// to the base URI, if possible, before writing. |
| /// |
| /// All the keys of [packageMapping] must be valid package names, |
| /// and the values must be URIs that do not have the `package:` scheme. |
| void write(StringSink output, Map<String, Uri> packageMapping, |
| {Uri baseUri, String comment}) { |
| if (baseUri != null && !baseUri.isAbsolute) { |
| throw new ArgumentError.value(baseUri, "baseUri", "Must be absolute"); |
| } |
| |
| if (comment != null) { |
| var lines = comment.split('\n'); |
| if (lines.last.isEmpty) lines.removeLast(); |
| for (var commentLine in lines) { |
| output.write('# '); |
| output.writeln(commentLine); |
| } |
| } else { |
| output.write("# generated by package:package_config at "); |
| output.write(new DateTime.now()); |
| output.writeln(); |
| } |
| |
| packageMapping.forEach((String packageName, Uri uri) { |
| // Validate packageName. |
| if (!isValidPackageName(packageName)) { |
| throw new ArgumentError('"$packageName" is not a valid package name'); |
| } |
| if (uri.scheme == "package") { |
| throw new ArgumentError.value( |
| "Package location must not be a package: URI", uri.toString()); |
| } |
| output.write(packageName); |
| output.write(':'); |
| // If baseUri provided, make uri relative. |
| if (baseUri != null) { |
| uri = _relativize(uri, baseUri); |
| } |
| output.write(uri); |
| if (!uri.path.endsWith('/')) { |
| output.write('/'); |
| } |
| output.writeln(); |
| }); |
| } |
| |
| /// Attempts to return a relative URI for [uri]. |
| /// |
| /// The result URI satisfies `baseUri.resolveUri(result) == uri`, |
| /// but may be relative. |
| /// The `baseUri` must be absolute. |
| Uri _relativize(Uri uri, Uri baseUri) { |
| assert(baseUri.isAbsolute); |
| if (uri.hasQuery || uri.hasFragment) { |
| uri = new Uri( |
| scheme: uri.scheme, |
| userInfo: uri.hasAuthority ? uri.userInfo : null, |
| host: uri.hasAuthority ? uri.host : null, |
| port: uri.hasAuthority ? uri.port : null, |
| path: uri.path); |
| } |
| |
| // Already relative. We assume the caller knows what they are doing. |
| if (!uri.isAbsolute) return uri; |
| |
| if (baseUri.scheme != uri.scheme) { |
| return uri; |
| } |
| |
| // If authority differs, we could remove the scheme, but it's not worth it. |
| if (uri.hasAuthority != baseUri.hasAuthority) return uri; |
| if (uri.hasAuthority) { |
| if (uri.userInfo != baseUri.userInfo || |
| uri.host.toLowerCase() != baseUri.host.toLowerCase() || |
| uri.port != baseUri.port) { |
| return uri; |
| } |
| } |
| |
| baseUri = _normalizePath(baseUri); |
| List<String> base = baseUri.pathSegments.toList(); |
| if (base.isNotEmpty) { |
| base = new List<String>.from(base)..removeLast(); |
| } |
| uri = _normalizePath(uri); |
| List<String> target = uri.pathSegments.toList(); |
| if (target.isNotEmpty && target.last.isEmpty) target.removeLast(); |
| int index = 0; |
| while (index < base.length && index < target.length) { |
| if (base[index] != target[index]) { |
| break; |
| } |
| index++; |
| } |
| if (index == base.length) { |
| if (index == target.length) { |
| return new Uri(path: "./"); |
| } |
| return new Uri(path: target.skip(index).join('/')); |
| } else if (index > 0) { |
| return new Uri( |
| path: '../' * (base.length - index) + target.skip(index).join('/')); |
| } else { |
| return uri; |
| } |
| } |
| |
| // TODO: inline to uri.normalizePath() when we move to 1.11 |
| Uri _normalizePath(Uri uri) => new Uri().resolveUri(uri); |