Command line parsing utilities. Not yet used in observatory.

runtime/observatory/test/command_test.dart

Index: runtime/observatory/test/command_test.dart
diff --git a/runtime/observatory/test/command_test.dart b/runtime/observatory/test/command_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..b87631ebbe75b29d6b44f7ef5af5588f590606b7
--- /dev/null
+++ b/runtime/observatory/test/command_test.dart
@@ -0,0 +1,193 @@
+// 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.
+
+import 'dart:async';
+
+import 'package:observatory/cli.dart';
+import 'package:unittest/unittest.dart';
+
+class TestCommand extends Command {
+  TestCommand(this.out, name, children) : super(name, children);
+  StringBuffer out;
+
+  Future run(List<String> args) {
+    out.write('executing ${name}(${args})\n');
+    return new Future.value(null);
+  }
+}
+
+class TestCompleteCommand extends Command {
+  TestCompleteCommand(this.out, name, children) : super(name, children);
+  StringBuffer out;
+
+  List<String> complete(List<String> args) {
+    var possibles = ['one ', 'two ', 'three '];
+    return possibles.where((possible) => possible.startsWith(args[0])).toList();
+  }
+
+  Future run(List<String> args) {
+    out.write('executing ${name}(${args})\n');
+    return new Future.value(null);
+  }
+}
+
+void testCommandComplete() {
+  RootCommand cmd =
+      new RootCommand([new TestCommand(null, 'alpha', []),
+
+                       new TestCommand(null, 'game', [
+                           new TestCommand(null, 'checkers', []),
+                           new TestCommand(null, 'chess', [])]),
+
+                       new TestCommand(null, 'gamera', [
+                           new TestCommand(null, 'london', []),
+                           new TestCommand(null, 'tokyo', []),
+                           new TestCommand(null, 'topeka', [])]),
+
+                       new TestCompleteCommand(null, 'count', [
+                           new TestCommand(null, 'chocula', [])])]);
+
+  // Show all commands.
+  expect(cmd.completeCommand(''),
+         equals(['alpha ', 'game ', 'gamera ', 'count ']));
+
+  // Substring completion.
+  expect(cmd.completeCommand('al'),
+         equals(['alpha ']));
+
+  // Full string completion.
+  expect(cmd.completeCommand('alpha'),
+         equals(['alpha ']));
+                      
+  // Extra space, no subcommands.
+  expect(cmd.completeCommand('alpha '),
+         equals(['alpha ']));
+
+  // Ambiguous completion.
+  expect(cmd.completeCommand('g'),
+         equals(['game ', 'gamera ']));
+
+  // Ambiguous completion, exact match not preferred.
+  expect(cmd.completeCommand('game'),
+         equals(['game ', 'gamera ']));
+
+  // Show all subcommands.
+  expect(cmd.completeCommand('gamera '),
+         equals(['gamera london ', 'gamera tokyo ', 'gamera topeka ']));
+
+  // Subcommand completion.
+  expect(cmd.completeCommand('gamera l'),
+         equals(['gamera london ']));
+
+  // Extra space, with subcommand.
+  expect(cmd.completeCommand('gamera london '),
+         equals(['gamera london ']));
+
+  // Ambiguous subcommand completion.
+  expect(cmd.completeCommand('gamera t'),
+         equals(['gamera tokyo ', 'gamera topeka ']));
+
+  // Ambiguous subcommand completion with substring prefix.
+  // Note that the prefix is left alone.
+  expect(cmd.completeCommand('gamer t'),
+         equals(['gamer tokyo ', 'gamer topeka ']));
+
+  // Ambiguous but exact prefix is preferred.
+  expect(cmd.completeCommand('game chec'),
+         equals(['game checkers ']));
+
+  // Ambiguous non-exact prefix means no matches.
+  expect(cmd.completeCommand('gam chec'),
+         equals([]));
+
+  // Locals + subcommands, show all.
+  expect(cmd.completeCommand('count '),
+         equals(['count chocula ',
+                 'count one ',
+                 'count two ',
+                 'count three ']));
+
+  // Locals + subcommands, single local match.
+  expect(cmd.completeCommand('count th '),
+         equals(['count three ']));
+
+  // Locals + subcommands, ambiguous local match.
+  expect(cmd.completeCommand('count t'),
+         equals(['count two ', 'count three ']));
+
+  // Locals + subcommands, single command match.
+  expect(cmd.completeCommand('co choc'),
+         equals(['co chocula ']));
+
+  // We gobble spare spaces, even in the prefix.
+  expect(cmd.completeCommand('    game    chec'), equals(['game checkers ']));
+}
+
+void testCommandRunSimple() {
+  // Run a simple command.
+  StringBuffer out = new StringBuffer();
+  RootCommand cmd = new RootCommand([new TestCommand(out, 'alpha', [])]);
+
+  // Full name dispatch works.  Argument passing works.
+  cmd.runCommand('alpha dog').then(expectAsync((_) {
+      expect(out.toString(), contains('executing alpha([dog])\n'));
+      out.clear();
+      // Substring dispatch works.
+      cmd.runCommand('al cat mouse').then(expectAsync((_) {
+          expect(out.toString(), contains('executing alpha([cat, mouse])\n'));
+      }));
+  }));
+}
+
+void testCommandRunSubcommand() {
+  // Run a simple command.
+  StringBuffer out = new StringBuffer();
+  RootCommand cmd =
+      new RootCommand([
+          new TestCommand(out, 'alpha', [
+              new TestCommand(out, 'beta', []),
+              new TestCommand(out, 'gamma', [])])]);
+      
+  cmd.runCommand('a b').then(expectAsync((_) {
+      expect(out.toString(), equals('executing beta([])\n'));
+      out.clear();
+      cmd.runCommand('alpha g ').then(expectAsync((_) {
+          expect(out.toString(), equals('executing gamma([])\n'));
+      }));
+  }));
+}
+
+void testCommandRunNotFound() {
+  // Run a simple command.
+  StringBuffer out = new StringBuffer();
+  RootCommand cmd = new RootCommand([new TestCommand(out, 'alpha', [])]);
+
+  cmd.runCommand('goose').catchError(expectAsync((e) {
+      expect(e, equals('notfound'));
+  }));
+}
+
+void testCommandRunAmbiguous() {
+  // Run a simple command.
+  StringBuffer out = new StringBuffer();
+  RootCommand cmd = new RootCommand([new TestCommand(out, 'alpha', []),
+                                     new TestCommand(out, 'ankle', [])]);
+
+  cmd.runCommand('a 55').catchError(expectAsync((e) {
+      expect(e, equals('ambiguous'));
+      out.clear();
+      cmd.runCommand('ankl 55').then(expectAsync((_) {
+          expect(out.toString(), equals('executing ankle([55])\n'));
+      }));
+  }));
+}
+
+main() {
+  test('command completion test suite', testCommandComplete);
+  test('run a simple command', testCommandRunSimple);
+  test('run a subcommand', testCommandRunSubcommand);
+  test('run a command which is not found', testCommandRunNotFound);
+  test('run a command which is ambiguous', testCommandRunAmbiguous);
+}
+