First check in for pub package manager.

utils/tests/pub/test_pub.dart

+// Copyright (c) 2012, 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.
+
+/**
+ * Test infrastructure for testing pub. Unlike typical unit tests, most pub
+ * tests are integration tests that stage some stuff on the file system, run
+ * pub, and then validate the results. This library provides an API to build
+ * tests like that.
+ */
+#library('test_pub');
+
+#import('dart:io');
+
+#import('../../../lib/unittest/unittest_vm.dart');
+#import('../../lib/file_system.dart');
+
+void testOutput(String description, List<String> pubArgs, String expected,
+    [int exitCode = 0]) {
+  asyncTest(description, 1, () {
+    // Find a dart executable we can use to run pub. Uses the one that the
+    // test infrastructure uses.
+    final scriptDir = new File(new Options().script).directorySync().path;
+    final platform = new Platform().operatingSystem();
+    final dartBin = joinPaths(scriptDir,
+        '../../../tools/testing/bin/$platform/dart');

[kasperl, 2012/04/11 07:17:03]

You sometimes indent these with 4 spaces and sometimes 2.

[Bob Nystrom, 2012/04/11 16:50:23]

Normal indentation should be 2 spaces, and line continuations should be 4 (or
more, to align with stuff). I think that's more or less Google standard style,
though you're right that there are probably mistakes where I'm not following it
right.

+
+    // Find the main pub entrypoint.
+    final pubPath = joinPaths(scriptDir, '../../pub/pub.dart');
+
+    final args = [pubPath];
+    args.addAll(pubArgs);
+
+    final process = new Process.start(dartBin, args);
+    final outStream = new StringInputStream(process.stdout);
+    final output = <String>[];
+    bool processDone = false;
+
+    checkComplete() {
+      if (!outStream.closed) return;
+      if (!processDone) return;
+
+      _validateOutput(expected, output);
+      callbackDone();
+    }
+
+    process.stderr.pipe(stderr, close: false);
+
+    outStream.onLine = () {
+      output.add(outStream.readLine());
+    };
+
+    outStream.onClosed = checkComplete;
+
+    process.onError = (error) {
+      Expect.fail('Failed to run pub: $error');
+      processDone = true;
+    };
+
+    process.onExit = (actualExitCode) {
+      Expect.equals(actualExitCode, exitCode,
+          'Pub returned exit code $actualExitCode, expected $exitCode.');
+      processDone = true;
+      checkComplete();
+    };
+  });
+}
+
+/**
+ * Compares the [actual] output from running pub with [expectedText]. Ignores
+ * leading and trailing whitespace differences and tries to report the
+ * offending difference in a nice way.
+ */
+void _validateOutput(String expectedText, List<String> actual) {
+  final expected = expectedText.split('\n');
+
+  final length = Math.min(expected.length, actual.length);
+  for (var i = 0; i < length; i++) {
+    if (expected[i].trim() != actual[i].trim()) {
+      Expect.fail(
+        'Output line ${i + 1} was: ${actual[i]}\nexpected: ${expected[i]}');
+    }
+  }
+
+  if (expected.length > actual.length) {
+    final message = new StringBuffer();
+    message.add('Missing expected output:\n');
+    for (var i = actual.length; i < expected.length; i++) {
+      message.add(expected[i]);
+      message.add('\n');
+    }
+
+    Expect.fail(message.toString());
+  }
+
+  if (expected.length < actual.length) {
+    final message = new StringBuffer();
+    message.add('Unexpected output:\n');
+    for (var i = expected.length; i < actual.length; i++) {
+      message.add(actual[i]);
+      message.add('\n');
+    }
+
+    Expect.fail(message.toString());
+  }
+}