pkg/test: Fix a few analyzer warnings

test/io.dart

 // 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.
 
 // TODO(nweiz): Remove this tag when we can get [packageDir] working without it
 // (dart-lang/sdk#24022).
 library test.test.io;
 
 import 'dart:async';
 import 'dart:io';
-import 'dart:isolate';
 
 import 'package:package_resolver/package_resolver.dart';
 import 'package:path/path.dart' as p;
 import 'package:scheduled_test/descriptor.dart' as d;
 import 'package:scheduled_test/scheduled_process.dart';
 import 'package:scheduled_test/scheduled_stream.dart';
 import 'package:scheduled_test/scheduled_test.dart';
 import 'package:test/src/util/io.dart';
 
 /// The path to the root directory of the `test` package.
@@ skipping 105 matching lines @@
     process.stdoutStream().listen(print);
     process.stderrStream().listen(print);
   }
 
   return process;
 }
 
 /// Runs Dart.
 ScheduledProcess runDart(List<String> args, {Map<String, String> environment,
     String description}) {
-  var allArgs = Platform.executableArguments
-      .where((arg) =>
-          !arg.startsWith("--package-root=") && !arg.startsWith("--packages="))
-      .toList()
-      ..add(PackageResolver.current.processArgument)
-      ..addAll(args);
+  var allArgs = <Object>[]

[nweiz, 2016/08/30 20:23:20]

<String>[]

[kevmoo, 2016/08/30 22:11:49]

Nope. This was the problem. This contains both `String` and `Future<String>`
hence the need for the fix.

+    ..addAll(Platform.executableArguments.where((arg) =>
+        !arg.startsWith("--package-root=") && !arg.startsWith("--packages=")))
+    ..add(PackageResolver.current.processArgument)
+    ..addAll(args);
 
   return new ScheduledProcess.start(
       p.absolute(Platform.resolvedExecutable), allArgs,
       workingDirectory: _sandbox,
       environment: environment,
       description: description);
 }
 
 /// Runs Pub.
 ScheduledProcess runPub(List args, {Map<String, String> environment}) {
@@ skipping 22 matching lines @@
     var match;
     while (match == null) {
       var line = await pub.stdout.next();
       match = _servingRegExp.firstMatch(line);
     }
     _pubServePortCompleter.complete(int.parse(match[1]));
   }, "waiting for pub serve to emit its port number");
 
   return pub;
 }