Use pub list-package-dirs in analyzer command line

pkg/analysis_server/lib/src/package_map_provider.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 package.map.provider;
-
-import 'dart:collection';
-import 'dart:convert';
-import 'dart:io' as io;
-
-import 'package:analyzer/file_system/file_system.dart';
-import 'package:analyzer/src/generated/engine.dart';
-import 'package:analyzer/src/generated/sdk_io.dart';
-import 'package:path/path.dart';
-
-/**
- * Data structure output by PackageMapProvider.  This contains both the package
- * map and dependency information.
- */
-class PackageMapInfo {
-  /**
-   * The package map itself.  This is a map from package name to a list of
-   * the folders containing source code for the package.
-   *
-   * `null` if an error occurred.
-   */
-  Map<String, List<Folder>> packageMap;
-
-  /**
-   * Dependency information.  This is a set of the paths which were consulted
-   * in order to generate the package map.  If any of these files is
-   * modified, the package map will need to be regenerated.
-   */
-  Set<String> dependencies;
-
-  PackageMapInfo(this.packageMap, this.dependencies);
-}
-
-/**
- * A PackageMapProvider is an entity capable of determining the mapping from
- * package name to source directory for a given folder.
- */
-abstract class PackageMapProvider {
-  /**
-   * Compute a package map for the given folder, if possible.
-   *
-   * If a package map can't be computed (e.g. because an error occurred), a
-   * [PackageMapInfo] will still be returned, but its packageMap will be null.
-   */
-  PackageMapInfo computePackageMap(Folder folder);
-}
-
-/**
- * Implementation of PackageMapProvider that operates by executing pub.
- */
-class PubPackageMapProvider implements PackageMapProvider {
-  static const String PUB_LIST_COMMAND = 'list-package-dirs';
-
-  /**
-   * The name of the 'pubspec.lock' file, which we assume is the dependency
-   * in the event that [PUB_LIST_COMMAND] fails.
-   */
-  static const String PUBSPEC_LOCK_NAME = 'pubspec.lock';
-
-  /**
-   * [ResourceProvider] that is used to create the [Folder]s that populate the
-   * package map.
-   */
-  final ResourceProvider resourceProvider;
-
-  /**
-   * Sdk that we use to find the pub executable.
-   */
-  final DirectoryBasedDartSdk sdk;
-
-  PubPackageMapProvider(this.resourceProvider, this.sdk);
-
-  @override
-  PackageMapInfo computePackageMap(Folder folder) {
-    // TODO(paulberry) make this asynchronous so that we can (a) do other
-    // analysis while it's in progress, and (b) time out if it takes too long
-    // to respond.
-    String executable = sdk.pubExecutable.getAbsolutePath();
-    io.ProcessResult result;
-    try {
-      result = io.Process.runSync(
-          executable, [PUB_LIST_COMMAND], workingDirectory: folder.path);
-    } on io.ProcessException catch (exception, stackTrace) {
-      AnalysisEngine.instance.logger.logInformation(
-          "Error running pub $PUB_LIST_COMMAND\n${exception}\n${stackTrace}");
-    }
-    if (result.exitCode != 0) {
-      AnalysisEngine.instance.logger.logInformation(
-          "pub $PUB_LIST_COMMAND failed: exit code ${result.exitCode}");
-      return _error(folder);
-    }
-    try {
-      return parsePackageMap(result.stdout, folder);
-    } catch (exception, stackTrace) {
-      AnalysisEngine.instance.logger.logError(
-          "Malformed output from pub $PUB_LIST_COMMAND\n${exception}\n${stackTrace}");
-    }
-
-    return _error(folder);
-  }
-
-  /**
-   * Decode the JSON output from pub into a package map.  Paths in the
-   * output are considered relative to [folder].
-   */
-  PackageMapInfo parsePackageMap(String jsonText, Folder folder) {
-    // The output of pub looks like this:
-    // {
-    //   "packages": {
-    //     "foo": "path/to/foo",
-    //     "bar": ["path/to/bar1", "path/to/bar2"],
-    //     "myapp": "path/to/myapp",  // self link is included
-    //   },
-    //   "input_files": [
-    //     "path/to/myapp/pubspec.lock"
-    //   ]
-    // }
-    Map<String, List<Folder>> packageMap = new HashMap<String, List<Folder>>();
-    Map obj = JSON.decode(jsonText);
-    Map packages = obj['packages'];
-    processPaths(String packageName, List paths) {
-      List<Folder> folders = <Folder>[];
-      for (var path in paths) {
-        if (path is String) {
-          Resource resource = folder.getChild(path);
-          if (resource is Folder) {
-            folders.add(resource);
-          }
-        }
-      }
-      if (folders.isNotEmpty) {
-        packageMap[packageName] = folders;
-      }
-    }
-    packages.forEach((key, value) {
-      if (value is String) {
-        processPaths(key, [value]);
-      } else if (value is List) {
-        processPaths(key, value);
-      }
-    });
-    Set<String> dependencies = new Set<String>();
-    List inputFiles = obj['input_files'];
-    if (inputFiles != null) {
-      for (var path in inputFiles) {
-        if (path is String) {
-          dependencies.add(folder.canonicalizePath(path));
-        }
-      }
-    }
-    return new PackageMapInfo(packageMap, dependencies);
-  }
-
-  /**
-   * Create a PackageMapInfo object representing an error condition.
-   */
-  PackageMapInfo _error(Folder folder) {
-    // Even if an error occurs, we still need to know the dependencies, so that
-    // we'll know when to try running "pub list-package-dirs" again.
-    // Unfortunately, "pub list-package-dirs" doesn't tell us dependencies when
-    // an error occurs, so just assume there is one dependency, "pubspec.lock".
-    List<String> dependencies = <String>[join(folder.path, PUBSPEC_LOCK_NAME)];
-    return new PackageMapInfo(null, dependencies.toSet());
-  }
-}