Add indication of instrumentation active/inactive to analysis server status.

pkg/analyzer/lib/instrumentation/instrumentation.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 instrumentation;
 
 /**
  * A container with analysis performance constants.
  */
 class AnalysisPerformanceKind {
@@ skipping 58 matching lines @@
    */
   InstrumentationServer _instrumentationServer;
 
   /**
    * Initialize a newly created instrumentation service to comunicate with the
    * given [instrumentationServer].
    */
   InstrumentationService(this._instrumentationServer);
 
   /**
+   * Return true if this [InstrumentationService] was initialized with a

[Brian Wilkerson, 2015/01/13 22:33:29]

nit: "true" --> "`true`", "null" --> "`null`"

[Paul Berry, 2015/01/14 18:23:03]

Done.

+   * non-null server (and hence instrumentation is active).
+   */
+  bool get isActive => _instrumentationServer != null;
+
+  /**
    * The current time, expressed as a decimal encoded number of milliseconds.
    */
   String get _timestamp => new DateTime.now().millisecondsSinceEpoch.toString();
 
   /**
    * Log the fact that an error, described by the given [message], has occurred.
    */
   void logError(String message) {
     _log(TAG_ERROR, message);
   }
 
   /**
    * Log that the given non-priority [exception] was thrown, with the given
    * [stackTrace].
    */
   void logException(dynamic exception, StackTrace stackTrace) {
     if (_instrumentationServer != null) {
       String message = _toString(exception);
       String trace = _toString(stackTrace);
       _instrumentationServer.log(_join([TAG_EXCEPTION, message, trace]));
     }
   }
 
   /**
    * Log that the contents of the file with the given [path] were read. The file
    * had the given [content] and [modificationTime].
    */
   void logFileRead(String path, int modificationTime, String content) {
     if (_instrumentationServer != null) {

[Brian Wilkerson, 2015/01/13 22:33:29]

We should replace existing tests of this form with "isActive".

[Paul Berry, 2015/01/14 18:23:03]

Agreed.  I'll do a follow-up CL.

       String timeStamp = _toString(modificationTime);
-      _instrumentationServer.log(_join([TAG_FILE_READ, path, timeStamp, content]));
+      _instrumentationServer.log(
+          _join([TAG_FILE_READ, path, timeStamp, content]));
     }
   }
 
   /**
    * Log that a log entry that was written to the analysis engine's log. The log
    * entry has the given [level] and [message], and was created at the given
    * [time].
    */
   void logLogEntry(String level, DateTime time, String message) {
     if (_instrumentationServer != null) {
-      String timeStamp = time == null ? 'null' : time.millisecondsSinceEpoch.toString();
+      String timeStamp =
+          time == null ? 'null' : time.millisecondsSinceEpoch.toString();
       _instrumentationServer.log(
           _join([TAG_LOG_ENTRY, level, timeStamp, message]));
     }
   }
 
   /**
    * Log that a notification has been sent to the client.
    */
   void logNotification(String notification) {
     _log(TAG_NOTIFICATION, notification);
@@ skipping 125 matching lines @@
     }
   }
 
   @override
   void shutdown() {
     for (InstrumentationServer server in _servers) {
       server.shutdown();
     }
   }
 }