Add support for running pub for plugins

pkg/analysis_server/lib/src/plugin/plugin_manager.dart

 // Copyright (c) 2017, 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:async';
 import 'dart:collection';
-import 'dart:io' show Platform;
+import 'dart:convert';
+import 'dart:io' show Platform, Process, ProcessResult;
 
 import 'package:analysis_server/src/plugin/notification_manager.dart';
 import 'package:analyzer/context/context_root.dart' as analyzer;
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/src/generated/bazel.dart';
 import 'package:analyzer/src/generated/gn.dart';
 import 'package:analyzer/src/util/glob.dart';
 import 'package:analyzer_plugin/channel/channel.dart';
 import 'package:analyzer_plugin/protocol/protocol.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart';
 import 'package:analyzer_plugin/protocol/protocol_constants.dart';
 import 'package:analyzer_plugin/protocol/protocol_generated.dart';
 import 'package:analyzer_plugin/src/channel/isolate_channel.dart';
 import 'package:analyzer_plugin/src/protocol/protocol_internal.dart';
 import 'package:convert/convert.dart';
 import 'package:crypto/crypto.dart';
 import 'package:meta/meta.dart';
+import 'package:path/path.dart' as path;
 import 'package:watcher/watcher.dart' as watcher;
 
 /**
  * Information about a plugin that is built-in.
  */
 class BuiltInPluginInfo extends PluginInfo {
   /**
    * The entry point function that will be executed in the plugin's isolate.
    */
   final EntryPoint entryPoint;
@@ skipping 290 matching lines @@
    */
   Future<Null> addPluginToContextRoot(
       analyzer.ContextRoot contextRoot, String path) async {
     if (!_isWhitelisted(path)) {
       return;
     }
     PluginInfo plugin = _pluginMap[path];
     bool isNew = plugin == null;
     if (isNew) {
       List<String> pluginPaths = _pathsFor(path);
-      if (pluginPaths == null) {
+      if (pluginPaths == null || pluginPaths[1] == null) {
         return;
       }
       plugin = new DiscoveredPluginInfo(path, pluginPaths[0], pluginPaths[1],
           notificationManager, instrumentationService);
       _pluginMap[path] = plugin;
       if (pluginPaths[0] != null) {
         PluginSession session = await plugin.start(byteStorePath, sdkPath);
         session?.onDone?.then((_) {
           _pluginMap.remove(path);
         });
@@ skipping 224 matching lines @@
     List<String> computePaths(Folder pluginFolder, {bool runPub: false}) {
       File pluginFile = pluginFolder
           .getChildAssumingFolder('bin')
           .getChildAssumingFile('plugin.dart');
       if (!pluginFile.exists) {
         return null;
       }
       File packagesFile = pluginFolder.getChildAssumingFile('.packages');
       if (!packagesFile.exists) {
         if (runPub) {
-          // TODO(brianwilkerson) Run pub in the pluginFolder.
+          String vmPath = Platform.executable;
+          String pubPath = path.join(path.dirname(vmPath), 'pub');
+          ProcessResult result = Process.runSync(pubPath, <String>['get'],
+              stderrEncoding: UTF8,
+              stdoutEncoding: UTF8,
+              workingDirectory: pluginFolder.path);
+          if (result.exitCode != 0) {
+            StringBuffer buffer = new StringBuffer();
+            buffer.writeln('Failed to run pub get');
+            buffer.writeln('  pluginFolder = ${pluginFolder.path}');
+            buffer.writeln('  exitCode = ${result.exitCode}');
+            buffer.writeln('  stdout = ${result.stdout}');
+            buffer.writeln('  stderr = ${result.stderr}');
+            instrumentationService.logError(buffer.toString());
+          }
           if (!packagesFile.exists) {
             packagesFile = null;
           }
         } else {
           packagesFile = null;
         }
       }
       return <String>[pluginFile.path, packagesFile?.path];
     }
 
@@ skipping 288 matching lines @@
    * The completer that will be used to complete the future when the response is
    * received from the plugin.
    */
   final Completer<Response> completer;
 
   /**
    * Initialize a pending request.
    */
   _PendingRequest(this.method, this.requestTime, this.completer);
 }