UsageException isn't called UsageError.

test/command_runner_test.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.
 
 import 'package:args/command_runner.dart';
 import 'package:test/test.dart';
 
 import 'utils.dart';
 
 const _DEFAULT_USAGE = """
@@ skipping 121 matching lines @@
 Available commands:
   aliased   Set a value.
   help      Display help information for test.
 
 Run "test help <command>" for more information about a command."""));
     });
   });
 
   test("usageException splits up the message and usage", () {
     expect(() => runner.usageException("message"),
-        throwsUsageError("message", _DEFAULT_USAGE));
+        throwsUsageException("message", _DEFAULT_USAGE));
   });
 
   group("run()", () {
     test("runs a command", () {
       var command = new FooCommand();
       runner.addCommand(command);
 
       expect(runner.run(["foo"]).then((_) {
         expect(command.hasRun, isTrue);
       }), completes);
@@ skipping 102 matching lines @@
 
     test("includes the footer in the usage string", () {
       expect(runner.usage, equals("""
 A test command runner.
 
 $_DEFAULT_USAGE
 Also, footer!"""));
     });
 
     test("includes the footer in usage errors", () {
-      expect(runner.run(["--bad"]), throwsUsageError(
+      expect(runner.run(["--bad"]), throwsUsageException(
           'Could not find an option named "bad".',
           "$_DEFAULT_USAGE\nAlso, footer!"));
     });
   });
 
   group("throws a useful error when", () {
     test("arg parsing fails", () {
-      expect(runner.run(["--bad"]), throwsUsageError(
+      expect(runner.run(["--bad"]), throwsUsageException(
           'Could not find an option named "bad".', _DEFAULT_USAGE));
     });
 
     test("a top-level command doesn't exist", () {
-      expect(runner.run(["bad"]), throwsUsageError(
+      expect(runner.run(["bad"]), throwsUsageException(
           'Could not find a command named "bad".', _DEFAULT_USAGE));
     });
 
     test("a subcommand doesn't exist", () {
       runner.addCommand(new FooCommand()..addSubcommand(new AsyncCommand()));
 
-      expect(runner.run(["foo bad"]), throwsUsageError(
+      expect(runner.run(["foo bad"]), throwsUsageException(
           'Could not find a command named "foo bad".', """
 Usage: test <command> [arguments]
 
 Global options:
 -h, --help    Print this usage information.
 
 Available commands:
   foo    Set a value.
   help   Display help information for test.
 
 Run "test help <command>" for more information about a command."""));
     });
 
     test("a subcommand wasn't passed", () {
       runner.addCommand(new FooCommand()..addSubcommand(new AsyncCommand()));
 
-      expect(runner.run(["foo"]), throwsUsageError(
+      expect(runner.run(["foo"]), throwsUsageException(
           'Missing subcommand for "test foo".', """
 Usage: test foo <subcommand> [arguments]
 -h, --help    Print this usage information.
 
 Available subcommands:
   async   Set a value asynchronously.
 
 Run "test help" to see global options."""));
     });
 
     test("a command that doesn't take arguments was given them", () {
       runner.addCommand(new FooCommand());
 
-      expect(runner.run(["foo", "bar"]), throwsUsageError(
+      expect(runner.run(["foo", "bar"]), throwsUsageException(
           'Command "foo" does not take any arguments.', """
 Usage: test foo [arguments]
 -h, --help    Print this usage information.
 
 Run "test help" to see global options."""));
     });
   });
 }