Revert "Revert "Use native async/await support in pub.""

sdk/lib/_internal/pub_generated/lib/src/source/hosted.dart

Index: sdk/lib/_internal/pub_generated/lib/src/source/hosted.dart
diff --git a/sdk/lib/_internal/pub_generated/lib/src/source/hosted.dart b/sdk/lib/_internal/pub_generated/lib/src/source/hosted.dart
deleted file mode 100644
index 37f27990ee55af76321848678e218e2a53c6f7ad..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub_generated/lib/src/source/hosted.dart
+++ /dev/null
@@ -1,450 +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.
-
-library pub.source.hosted;
-
-import 'dart:async';
-import 'dart:io' as io;
-import "dart:convert";
-
-import 'package:http/http.dart' as http;
-import 'package:path/path.dart' as path;
-import 'package:pub_semver/pub_semver.dart';
-
-import '../exceptions.dart';
-import '../http.dart';
-import '../io.dart';
-import '../log.dart' as log;
-import '../package.dart';
-import '../pubspec.dart';
-import '../utils.dart';
-import 'cached.dart';
-
-/// A package source that gets packages from a package hosting site that uses
-/// the same API as pub.dartlang.org.
-class HostedSource extends CachedSource {
-  final name = "hosted";
-  final hasMultipleVersions = true;
-
-  /// Gets the default URL for the package server for hosted dependencies.
-  static String get defaultUrl {
-    var url = io.Platform.environment["PUB_HOSTED_URL"];
-    if (url != null) return url;
-
-    return "https://pub.dartlang.org";
-  }
-
-  /// Downloads a list of all versions of a package that are available from the
-  /// site.
-  Future<List<Version>> getVersions(String name, description) {
-    var url =
-        _makeUrl(description, (server, package) => "$server/api/packages/$package");
-
-    log.io("Get versions from $url.");
-    return httpClient.read(url, headers: PUB_API_HEADERS).then((body) {
-      var doc = JSON.decode(body);
-      return doc['versions'].map(
-          (version) => new Version.parse(version['version'])).toList();
-    }).catchError((ex, stackTrace) {
-      var parsed = _parseDescription(description);
-      _throwFriendlyError(ex, stackTrace, parsed.first, parsed.last);
-    });
-  }
-
-  /// Downloads and parses the pubspec for a specific version of a package that
-  /// is available from the site.
-  Future<Pubspec> describeUncached(PackageId id) {
-    // Request it from the server.
-    var url = _makeVersionUrl(
-        id,
-        (server, package, version) =>
-            "$server/api/packages/$package/versions/$version");
-
-    log.io("Describe package at $url.");
-    return httpClient.read(url, headers: PUB_API_HEADERS).then((version) {
-      version = JSON.decode(version);
-
-      // TODO(rnystrom): After this is pulled down, we could place it in
-      // a secondary cache of just pubspecs. This would let us have a
-      // persistent cache for pubspecs for packages that haven't actually
-      // been downloaded.
-      return new Pubspec.fromMap(
-          version['pubspec'],
-          systemCache.sources,
-          expectedName: id.name,
-          location: url);
-    }).catchError((ex, stackTrace) {
-      var parsed = _parseDescription(id.description);
-      _throwFriendlyError(ex, stackTrace, id.name, parsed.last);
-    });
-  }
-
-  /// Downloads the package identified by [id] to the system cache.
-  Future<Package> downloadToSystemCache(PackageId id) {
-    return isInSystemCache(id).then((inCache) {
-      // Already cached so don't download it.
-      if (inCache) return true;
-
-      var packageDir = _getDirectory(id);
-      ensureDir(path.dirname(packageDir));
-      var parsed = _parseDescription(id.description);
-      return _download(parsed.last, parsed.first, id.version, packageDir);
-    }).then((found) {
-      if (!found) fail('Package $id not found.');
-      return new Package.load(id.name, _getDirectory(id), systemCache.sources);
-    });
-  }
-
-  /// The system cache directory for the hosted source contains subdirectories
-  /// for each separate repository URL that's used on the system.
-  ///
-  /// Each of these subdirectories then contains a subdirectory for each
-  /// package downloaded from that site.
-  Future<String> getDirectory(PackageId id) =>
-      new Future.value(_getDirectory(id));
-
-  String _getDirectory(PackageId id) {
-    var parsed = _parseDescription(id.description);
-    var dir = _urlToDirectory(parsed.last);
-    return path.join(systemCacheRoot, dir, "${parsed.first}-${id.version}");
-  }
-
-  String packageName(description) => _parseDescription(description).first;
-
-  bool descriptionsEqual(description1, description2) =>
-      _parseDescription(description1) == _parseDescription(description2);
-
-  /// Ensures that [description] is a valid hosted package description.
-  ///
-  /// There are two valid formats. A plain string refers to a package with the
-  /// given name from the default host, while a map with keys "name" and "url"
-  /// refers to a package with the given name from the host at the given URL.
-  dynamic parseDescription(String containingPath, description,
-      {bool fromLockFile: false}) {
-    _parseDescription(description);
-    return description;
-  }
-
-  /// Re-downloads all packages that have been previously downloaded into the
-  /// system cache from any server.
-  Future<Pair<int, int>> repairCachedPackages() {
-    final completer0 = new Completer();
-    scheduleMicrotask(() {
-      try {
-        join0() {
-          var successes = 0;
-          var failures = 0;
-          var it0 = listDir(systemCacheRoot).iterator;
-          break0() {
-            completer0.complete(new Pair(successes, failures));
-          }
-          var trampoline0;
-          continue0() {
-            trampoline0 = null;
-            if (it0.moveNext()) {
-              var serverDir = it0.current;
-              var url = _directoryToUrl(path.basename(serverDir));
-              var packages =
-                  _getCachedPackagesInDirectory(path.basename(serverDir));
-              packages.sort(Package.orderByNameAndVersion);
-              var it1 = packages.iterator;
-              break1() {
-                trampoline0 = continue0;
-                do trampoline0(); while (trampoline0 != null);
-              }
-              var trampoline1;
-              continue1() {
-                trampoline1 = null;
-                if (it1.moveNext()) {
-                  var package = it1.current;
-                  join1() {
-                    trampoline1 = continue1;
-                    do trampoline1(); while (trampoline1 != null);
-                  }
-                  catch0(error, stackTrace) {
-                    try {
-                      failures++;
-                      var message =
-                          "Failed to repair ${log.bold(package.name)} " "${package.version}";
-                      join2() {
-                        log.error("${message}. Error:\n${error}");
-                        log.fine(stackTrace);
-                        tryDeleteEntry(package.dir);
-                        join1();
-                      }
-                      if (url != defaultUrl) {
-                        message += " from ${url}";
-                        join2();
-                      } else {
-                        join2();
-                      }
-                    } catch (error, stackTrace) {
-                      completer0.completeError(error, stackTrace);
-                    }
-                  }
-                  try {
-                    new Future.value(
-                        _download(url, package.name, package.version, package.dir)).then((x0) {
-                      trampoline1 = () {
-                        trampoline1 = null;
-                        try {
-                          x0;
-                          successes++;
-                          join1();
-                        } catch (e0, s0) {
-                          catch0(e0, s0);
-                        }
-                      };
-                      do trampoline1(); while (trampoline1 != null);
-                    }, onError: catch0);
-                  } catch (e1, s1) {
-                    catch0(e1, s1);
-                  }
-                } else {
-                  break1();
-                }
-              }
-              trampoline1 = continue1;
-              do trampoline1(); while (trampoline1 != null);
-            } else {
-              break0();
-            }
-          }
-          trampoline0 = continue0;
-          do trampoline0(); while (trampoline0 != null);
-        }
-        if (!dirExists(systemCacheRoot)) {
-          completer0.complete(new Pair(0, 0));
-        } else {
-          join0();
-        }
-      } catch (e, s) {
-        completer0.completeError(e, s);
-      }
-    });
-    return completer0.future;
-  }
-
-  /// Gets all of the packages that have been downloaded into the system cache
-  /// from the default server.
-  List<Package> getCachedPackages() {
-    return _getCachedPackagesInDirectory(_urlToDirectory(defaultUrl));
-  }
-
-  /// Gets all of the packages that have been downloaded into the system cache
-  /// into [dir].
-  List<Package> _getCachedPackagesInDirectory(String dir) {
-    var cacheDir = path.join(systemCacheRoot, dir);
-    if (!dirExists(cacheDir)) return [];
-
-    return listDir(
-        cacheDir).map(
-            (entry) => new Package.load(null, entry, systemCache.sources)).toList();
-  }
-
-  /// Downloads package [package] at [version] from [server], and unpacks it
-  /// into [destPath].
-  Future<bool> _download(String server, String package, Version version,
-      String destPath) {
-    return new Future.sync(() {
-      var url = Uri.parse("$server/packages/$package/versions/$version.tar.gz");
-      log.io("Get package from $url.");
-      log.message('Downloading ${log.bold(package)} ${version}...');
-
-      // Download and extract the archive to a temp directory.
-      var tempDir = systemCache.createTempDir();
-      return httpClient.send(
-          new http.Request(
-              "GET",
-              url)).then((response) => response.stream).then((stream) {
-        return timeout(
-            extractTarGz(stream, tempDir),
-            HTTP_TIMEOUT,
-            url,
-            'downloading $url');
-      }).then((_) {
-        // Remove the existing directory if it exists. This will happen if
-        // we're forcing a download to repair the cache.
-        if (dirExists(destPath)) deleteEntry(destPath);
-
-        // Now that the get has succeeded, move it to the real location in the
-        // cache. This ensures that we don't leave half-busted ghost
-        // directories in the user's pub cache if a get fails.
-        renameDir(tempDir, destPath);
-        return true;
-      });
-    });
-  }
-
-  /// When an error occurs trying to read something about [package] from [url],
-  /// this tries to translate into a more user friendly error message.
-  ///
-  /// Always throws an error, either the original one or a better one.
-  void _throwFriendlyError(error, StackTrace stackTrace, String package,
-      String url) {
-    if (error is PubHttpException && error.response.statusCode == 404) {
-      throw new PackageNotFoundException(
-          "Could not find package $package at $url.",
-          error,
-          stackTrace);
-    }
-
-    if (error is TimeoutException) {
-      fail(
-          "Timed out trying to find package $package at $url.",
-          error,
-          stackTrace);
-    }
-
-    if (error is io.SocketException) {
-      fail(
-          "Got socket error trying to find package $package at $url.",
-          error,
-          stackTrace);
-    }
-
-    // Otherwise re-throw the original exception.
-    throw error;
-  }
-}
-
-/// This is the modified hosted source used when pub get or upgrade are run
-/// with "--offline".
-///
-/// This uses the system cache to get the list of available packages and does
-/// no network access.
-class OfflineHostedSource extends HostedSource {
-  /// Gets the list of all versions of [name] that are in the system cache.
-  Future<List<Version>> getVersions(String name, description) {
-    return newFuture(() {
-      var parsed = _parseDescription(description);
-      var server = parsed.last;
-      log.io(
-          "Finding versions of $name in " "$systemCacheRoot/${_urlToDirectory(server)}");
-      return _getCachedPackagesInDirectory(
-          _urlToDirectory(
-              server)).where(
-                  (package) => package.name == name).map((package) => package.version).toList();
-    }).then((versions) {
-      // If there are no versions in the cache, report a clearer error.
-      if (versions.isEmpty) fail("Could not find package $name in cache.");
-
-      return versions;
-    });
-  }
-
-  Future<bool> _download(String server, String package, Version version,
-      String destPath) {
-    // Since HostedSource is cached, this will only be called for uncached
-    // packages.
-    throw new UnsupportedError("Cannot download packages when offline.");
-  }
-
-  Future<Pubspec> doDescribeUncached(PackageId id) {
-    // [getVersions()] will only return packages that are already cached.
-    // [CachedSource] will only call [doDescribeUncached()] on a package after
-    // it has failed to find it in the cache, so this code should not be
-    // reached.
-    throw new UnsupportedError("Cannot describe packages when offline.");
-  }
-}
-
-/// Given a URL, returns a "normalized" string to be used as a directory name
-/// for packages downloaded from the server at that URL.
-///
-/// This normalization strips off the scheme (which is presumed to be HTTP or
-/// HTTPS) and *sort of* URL-encodes it. I say "sort of" because it does it
-/// incorrectly: it uses the character's *decimal* ASCII value instead of hex.
-///
-/// This could cause an ambiguity since some characters get encoded as three
-/// digits and others two. It's possible for one to be a prefix of the other.
-/// In practice, the set of characters that are encoded don't happen to have
-/// any collisions, so the encoding is reversible.
-///
-/// This behavior is a bug, but is being preserved for compatibility.
-String _urlToDirectory(String url) {
-  // Normalize all loopback URLs to "localhost".
-  url = url.replaceAllMapped(
-      new RegExp(r"^https?://(127\.0\.0\.1|\[::1\])?"),
-      (match) => match[1] == null ? '' : 'localhost');
-  return replace(
-      url,
-      new RegExp(r'[<>:"\\/|?*%]'),
-      (match) => '%${match[0].codeUnitAt(0)}');
-}
-
-/// Given a directory name in the system cache, returns the URL of the server
-/// whose packages it contains.
-///
-/// See [_urlToDirectory] for details on the mapping. Note that because the
-/// directory name does not preserve the scheme, this has to guess at it. It
-/// chooses "http" for loopback URLs (mainly to support the pub tests) and
-/// "https" for all others.
-String _directoryToUrl(String url) {
-  // Decode the pseudo-URL-encoded characters.
-  var chars = '<>:"\\/|?*%';
-  for (var i = 0; i < chars.length; i++) {
-    var c = chars.substring(i, i + 1);
-    url = url.replaceAll("%${c.codeUnitAt(0)}", c);
-  }
-
-  // Figure out the scheme.
-  var scheme = "https";
-
-  // See if it's a loopback IP address.
-  if (isLoopback(url.replaceAll(new RegExp(":.*"), ""))) scheme = "http";
-  return "$scheme://$url";
-}
-
-/// Parses [description] into its server and package name components, then
-/// converts that to a Uri given [pattern].
-///
-/// Ensures the package name is properly URL encoded.
-Uri _makeUrl(description, String pattern(String server, String package)) {
-  var parsed = _parseDescription(description);
-  var server = parsed.last;
-  var package = Uri.encodeComponent(parsed.first);
-  return Uri.parse(pattern(server, package));
-}
-
-/// Parses [id] into its server, package name, and version components, then
-/// converts that to a Uri given [pattern].
-///
-/// Ensures the package name is properly URL encoded.
-Uri _makeVersionUrl(PackageId id, String pattern(String server, String package,
-    String version)) {
-  var parsed = _parseDescription(id.description);
-  var server = parsed.last;
-  var package = Uri.encodeComponent(parsed.first);
-  var version = Uri.encodeComponent(id.version.toString());
-  return Uri.parse(pattern(server, package, version));
-}
-
-/// Parses the description for a package.
-///
-/// If the package parses correctly, this returns a (name, url) pair. If not,
-/// this throws a descriptive FormatException.
-Pair<String, String> _parseDescription(description) {
-  if (description is String) {
-    return new Pair<String, String>(description, HostedSource.defaultUrl);
-  }
-
-  if (description is! Map) {
-    throw new FormatException("The description must be a package name or map.");
-  }
-
-  if (!description.containsKey("name")) {
-    throw new FormatException("The description map must contain a 'name' key.");
-  }
-
-  var name = description["name"];
-  if (name is! String) {
-    throw new FormatException("The 'name' key must have a string value.");
-  }
-
-  var url = description["url"];
-  if (url == null) url = HostedSource.defaultUrl;
-
-  return new Pair<String, String>(name, url);
-}