diff --git a/pkg/analyzer_cli/lib/src/analyzer_impl.dart b/pkg/analyzer_cli/lib/src/analyzer_impl.dart
index e36008f..617bdf9 100644
--- a/pkg/analyzer_cli/lib/src/analyzer_impl.dart
+++ b/pkg/analyzer_cli/lib/src/analyzer_impl.dart
@@ -1,9 +1,7 @@
-// Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2015, 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 analyzer_cli.src.analyzer_impl;
-
 import 'dart:async';
 import 'dart:io';
 
@@ -122,7 +120,7 @@
   }
 
   /// Fills [errorInfos] using [files].
-  Future<Null> prepareErrors() async {
+  Future<void> prepareErrors() async {
     // TODO(brianwilkerson) Determine whether this await is necessary.
     await null;
     PerformanceTag previous = _prepareErrorsTag.makeCurrent();
diff --git a/pkg/analyzer_cli/lib/src/build_mode.dart b/pkg/analyzer_cli/lib/src/build_mode.dart
index 7508eee..2c64108 100644
--- a/pkg/analyzer_cli/lib/src/build_mode.dart
+++ b/pkg/analyzer_cli/lib/src/build_mode.dart
@@ -77,7 +77,7 @@
   /**
    * Performs analysis with given [options].
    */
-  Future<Null> analyze(
+  Future<void> analyze(
       CommandLineOptions options, Map<String, WorkerInput> inputs) async {
     // TODO(brianwilkerson) Determine whether this await is necessary.
     await null;
@@ -147,7 +147,7 @@
    * Run the worker loop.
    */
   @override
-  Future<Null> run() async {
+  Future<void> run() async {
     // TODO(brianwilkerson) Determine whether this await is necessary.
     await null;
     errorSink = errorBuffer;
@@ -472,7 +472,7 @@
    *
    * Otherwise compute it and store into the [uriToUnit] and [assembler].
    */
-  Future<Null> _prepareUnlinkedUnit(String absoluteUri) async {
+  Future<void> _prepareUnlinkedUnit(String absoluteUri) async {
     // TODO(brianwilkerson) Determine whether this await is necessary.
     await null;
     // Maybe an input package contains the source.
@@ -497,7 +497,7 @@
    * Print errors for all explicit sources.  If [outputPath] is supplied, output
    * is sent to a new file at that path.
    */
-  Future<Null> _printErrors({String outputPath}) async {
+  Future<void> _printErrors({String outputPath}) async {
     // TODO(brianwilkerson) Determine whether this await is necessary.
     await null;
     await logger.runAsync('Compute and print analysis errors', () async {
diff --git a/pkg/analyzer_cli/lib/src/driver.dart b/pkg/analyzer_cli/lib/src/driver.dart
index 41a285e..8b2b808 100644
--- a/pkg/analyzer_cli/lib/src/driver.dart
+++ b/pkg/analyzer_cli/lib/src/driver.dart
@@ -165,9 +165,7 @@
   }
 
   @override
-  Future<Null> start(List<String> args, {SendPort sendPort}) async {
-    // TODO(brianwilkerson) Determine whether this await is necessary.
-    await null;
+  Future<void> start(List<String> args, {SendPort sendPort}) async {
     if (analysisDriver != null) {
       throw new StateError("start() can only be called once");
     }
diff --git a/pkg/analyzer_cli/lib/starter.dart b/pkg/analyzer_cli/lib/starter.dart
index 4caa91f..09db5bf 100644
--- a/pkg/analyzer_cli/lib/starter.dart
+++ b/pkg/analyzer_cli/lib/starter.dart
@@ -1,4 +1,4 @@
-// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2016, 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.
 
@@ -40,5 +40,5 @@
    * If [sendPort] is provided it is used for bazel worker communication
    * instead of stdin/stdout.
    */
-  Future<Null> start(List<String> arguments, {SendPort sendPort});
+  Future<void> start(List<String> arguments, {SendPort sendPort});
 }
diff --git a/pkg/analyzer_cli/test/analysis_options_test.dart b/pkg/analyzer_cli/test/analysis_options_test.dart
index b04f1a4..e8bd10a 100644
--- a/pkg/analyzer_cli/test/analysis_options_test.dart
+++ b/pkg/analyzer_cli/test/analysis_options_test.dart
@@ -1,3 +1,7 @@
+// 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:io';
 
@@ -71,7 +75,7 @@
 
   String get stdout => _stdout.toString();
 
-  Future<Null> run2(List<String> args) async {
+  Future<void> run2(List<String> args) async {
     await new Driver(isTesting: true).start(args);
     if (stderr.isNotEmpty) {
       fail("Unexpected output to stderr:\n$stderr");
diff --git a/pkg/analyzer_cli/test/build_mode_test.dart b/pkg/analyzer_cli/test/build_mode_test.dart
index 90655ef..25e884f 100644
--- a/pkg/analyzer_cli/test/build_mode_test.dart
+++ b/pkg/analyzer_cli/test/build_mode_test.dart
@@ -1,9 +1,7 @@
-// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2016, 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 analyzer_cli.test.built_mode;
-
 import 'dart:async';
 
 import 'package:analyzer/file_system/memory_file_system.dart';
@@ -32,7 +30,7 @@
       : super(new MemoryResourceProvider(), connection);
 
   @override
-  Future<Null> analyze(CommandLineOptions options, inputs) async {
+  Future<void> analyze(CommandLineOptions options, inputs) async {
     if (_analyze != null) {
       _analyze(options);
     }
diff --git a/pkg/analyzer_cli/test/driver_test.dart b/pkg/analyzer_cli/test/driver_test.dart
index 23a2841..aa44888 100644
--- a/pkg/analyzer_cli/test/driver_test.dart
+++ b/pkg/analyzer_cli/test/driver_test.dart
@@ -56,7 +56,7 @@
   /// [args] and an [options] file path. The value of [options] defaults to an
   /// empty options file to avoid unwanted configuration from an otherwise
   /// discovered options file.
-  Future<Null> drive(
+  Future<void> drive(
     String source, {
     String options: emptyOptionsFile,
     List<String> args: const <String>[],
@@ -65,7 +65,7 @@
   }
 
   /// Like [drive], but takes an array of sources.
-  Future<Null> driveMany(
+  Future<void> driveMany(
     List<String> sources, {
     String options: emptyOptionsFile,
     List<String> args: const <String>[],
@@ -211,7 +211,7 @@
 var b = a;
 ''');
 
-      Future<Null> buildUnlinked(String uri, String path, String output) async {
+      Future<void> buildUnlinked(String uri, String path, String output) async {
         await _doDrive(path, uri: uri, additionalArgs: [
           '--build-summary-only',
           '--build-summary-only-unlinked',
@@ -485,7 +485,7 @@
     });
   }
 
-  Future<Null> _doDrive(String path,
+  Future<void> _doDrive(String path,
       {String uri,
       List<String> additionalArgs: const [],
       String dartSdkSummaryPath}) async {
@@ -748,17 +748,17 @@
   YamlMap _parseOptions(String src) =>
       new AnalysisOptionsProvider().getOptionsFromString(src);
 
-  Future<Null> _runLinter_defaultLints() async {
+  Future<void> _runLinter_defaultLints() async {
     await drive('data/linter_project/test_file.dart',
         options: 'data/linter_project/$optionsFileName', args: ['--lints']);
   }
 
-  Future<Null> _runLinter_lintsInOptions() async {
+  Future<void> _runLinter_lintsInOptions() async {
     await drive('data/linter_project/test_file.dart',
         options: 'data/linter_project/$optionsFileName', args: ['--lints']);
   }
 
-  Future<Null> _runLinter_noLintsFlag() async {
+  Future<void> _runLinter_noLintsFlag() async {
     await drive('data/no_lints_project/test_file.dart',
         options: 'data/no_lints_project/$optionsFileName');
   }
@@ -917,7 +917,7 @@
     expect(outSink.toString(), contains("1 error and 1 warning found."));
   }
 
-  Future<Null> _driveBasic() async {
+  Future<void> _driveBasic() async {
     await drive('data/options_tests_project/test_file.dart',
         options: 'data/options_tests_project/$optionsFileName');
   }
diff --git a/pkg/analyzer_cli/test/package_prefix_test.dart b/pkg/analyzer_cli/test/package_prefix_test.dart
index a85fc16..61ae3b4 100644
--- a/pkg/analyzer_cli/test/package_prefix_test.dart
+++ b/pkg/analyzer_cli/test/package_prefix_test.dart
@@ -1,3 +1,7 @@
+// Copyright (c) 2016, 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:io' show exitCode;
 
@@ -60,7 +64,7 @@
 
   String get stdout => _stdout.toString();
 
-  Future<Null> run2(List<String> args) async {
+  Future<void> run2(List<String> args) async {
     await new Driver(isTesting: true).start(args);
     if (stderr.isNotEmpty) {
       fail("Unexpected output to stderr:\n$stderr");
diff --git a/pkg/analyzer_cli/test/utils.dart b/pkg/analyzer_cli/test/utils.dart
index 3d91aef..b12c19e 100644
--- a/pkg/analyzer_cli/test/utils.dart
+++ b/pkg/analyzer_cli/test/utils.dart
@@ -15,7 +15,7 @@
 
 /// Recursively copy the specified [src] directory (or file)
 /// to the specified destination path.
-Future<Null> recursiveCopy(FileSystemEntity src, String dstPath) async {
+Future<void> recursiveCopy(FileSystemEntity src, String dstPath) async {
   if (src is Directory) {
     await (new Directory(dstPath)).create(recursive: true);
     for (FileSystemEntity entity in src.listSync()) {