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

sdk/lib/_internal/pub_generated/lib/src/command/deps.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.
-
-library pub.command.list;
-
-import 'dart:async';
-import 'dart:collection';
-
-import '../ascii_tree.dart' as tree;
-import '../command.dart';
-import '../log.dart' as log;
-import '../package.dart';
-import '../package_graph.dart';
-import '../utils.dart';
-
-/// Handles the `deps` pub command.
-class DepsCommand extends PubCommand {
-  String get name => "deps";
-  String get description => "Print package dependencies.";
-  List<String> get aliases => const ["dependencies", "tab"];
-  String get invocation => "pub deps";
-  String get docUrl => "http://dartlang.org/tools/pub/cmd/pub-deps.html";
-  bool get takesArguments => false;
-
-  /// The loaded package graph.
-  PackageGraph _graph;
-
-  /// The [StringBuffer] used to accumulate the output.
-  StringBuffer _buffer;
-
-  DepsCommand() {
-    argParser.addOption(
-        "style",
-        abbr: "s",
-        help: "How output should be displayed.",
-        allowed: ["compact", "tree", "list"],
-        defaultsTo: "tree");
-  }
-
-  Future run() {
-    return entrypoint.loadPackageGraph().then((graph) {
-      _graph = graph;
-      _buffer = new StringBuffer();
-
-      _buffer.writeln(_labelPackage(entrypoint.root));
-
-      switch (argResults["style"]) {
-        case "compact":
-          _outputCompact();
-          break;
-        case "list":
-          _outputList();
-          break;
-        case "tree":
-          _outputTree();
-          break;
-      }
-
-      log.message(_buffer);
-    });
-  }
-
-  /// Outputs a list of all of the package's immediate, dev, override, and
-  /// transitive dependencies.
-  ///
-  /// For each dependency listed, *that* package's immediate dependencies are
-  /// shown. Unlike [_outputList], this prints all of these dependencies on one
-  /// line.
-  void _outputCompact() {
-    var root = entrypoint.root;
-    _outputCompactPackages(
-        "dependencies",
-        root.dependencies.map((dep) => dep.name));
-    _outputCompactPackages(
-        "dev dependencies",
-        root.devDependencies.map((dep) => dep.name));
-    _outputCompactPackages(
-        "dependency overrides",
-        root.dependencyOverrides.map((dep) => dep.name));
-
-    var transitive = _getTransitiveDependencies();
-    _outputCompactPackages("transitive dependencies", transitive);
-  }
-
-  /// Outputs one section of packages in the compact output.
-  _outputCompactPackages(String section, Iterable<String> names) {
-    if (names.isEmpty) return;
-
-    _buffer.writeln();
-    _buffer.writeln("$section:");
-    for (var name in ordered(names)) {
-      var package = _graph.packages[name];
-
-      _buffer.write("- ${_labelPackage(package)}");
-      if (package.dependencies.isEmpty) {
-        _buffer.writeln();
-      } else {
-        var depNames = package.dependencies.map((dep) => dep.name);
-        var depsList = "[${depNames.join(' ')}]";
-        _buffer.writeln(" ${log.gray(depsList)}");
-      }
-    }
-  }
-
-  /// Outputs a list of all of the package's immediate, dev, override, and
-  /// transitive dependencies.
-  ///
-  /// For each dependency listed, *that* package's immediate dependencies are
-  /// shown.
-  void _outputList() {
-    var root = entrypoint.root;
-    _outputListSection(
-        "dependencies",
-        root.dependencies.map((dep) => dep.name));
-    _outputListSection(
-        "dev dependencies",
-        root.devDependencies.map((dep) => dep.name));
-    _outputListSection(
-        "dependency overrides",
-        root.dependencyOverrides.map((dep) => dep.name));
-
-    var transitive = _getTransitiveDependencies();
-    if (transitive.isEmpty) return;
-
-    _outputListSection("transitive dependencies", ordered(transitive));
-  }
-
-  /// Outputs one section of packages in the list output.
-  _outputListSection(String name, Iterable<String> deps) {
-    if (deps.isEmpty) return;
-
-    _buffer.writeln();
-    _buffer.writeln("$name:");
-
-    for (var name in deps) {
-      var package = _graph.packages[name];
-      _buffer.writeln("- ${_labelPackage(package)}");
-
-      for (var dep in package.dependencies) {
-        _buffer.writeln(
-            "  - ${log.bold(dep.name)} ${log.gray(dep.constraint)}");
-      }
-    }
-  }
-
-  /// Generates a dependency tree for the root package.
-  ///
-  /// If a package is encountered more than once (i.e. a shared or circular
-  /// dependency), later ones are not traversed. This is done in breadth-first
-  /// fashion so that a package will always be expanded at the shallowest
-  /// depth that it appears at.
-  void _outputTree() {
-    // The work list for the breadth-first traversal. It contains the package
-    // being added to the tree, and the parent map that will receive that
-    // package.
-    var toWalk = new Queue<Pair<Package, Map>>();
-    var visited = new Set<String>();
-
-    // Start with the root dependencies.
-    var packageTree = {};
-    for (var dep in entrypoint.root.immediateDependencies) {
-      toWalk.add(new Pair(_graph.packages[dep.name], packageTree));
-    }
-
-    // Do a breadth-first walk to the dependency graph.
-    while (toWalk.isNotEmpty) {
-      var pair = toWalk.removeFirst();
-      var package = pair.first;
-      var map = pair.last;
-
-      if (visited.contains(package.name)) {
-        map[log.gray('${package.name}...')] = {};
-        continue;
-      }
-
-      visited.add(package.name);
-
-      // Populate the map with this package's dependencies.
-      var childMap = {};
-      map[_labelPackage(package)] = childMap;
-
-      for (var dep in package.dependencies) {
-        toWalk.add(new Pair(_graph.packages[dep.name], childMap));
-      }
-    }
-
-    _buffer.write(tree.fromMap(packageTree, showAllChildren: true));
-  }
-
-  String _labelPackage(Package package) =>
-      "${log.bold(package.name)} ${package.version}";
-
-  /// Gets the names of the non-immediate dependencies of the root package.
-  Set<String> _getTransitiveDependencies() {
-    var transitive = _graph.packages.keys.toSet();
-    var root = entrypoint.root;
-    transitive.remove(root.name);
-    transitive.removeAll(root.dependencies.map((dep) => dep.name));
-    transitive.removeAll(root.devDependencies.map((dep) => dep.name));
-    transitive.removeAll(root.dependencyOverrides.map((dep) => dep.name));
-    return transitive;
-  }
-}