Resolves #1856, fix regression in #1645. Includes some refactoring to make testing easier.

Signed-off-by: Daniel Nephin <dnephin@gmail.com>

tests/unit/cli/main_test.py

@@ -0,0 +1,47 @@
+from __future__ import absolute_import
+
+from compose import container
+from compose.cli.log_printer import LogPrinter
+from compose.cli.main import attach_to_logs
+from compose.cli.main import build_log_printer
+from compose.project import Project
+from tests import mock
+from tests import unittest
+
+
+def mock_container(service, number):
+    return mock.create_autospec(
+        container.Container,
+        service=service,
+        number=number,
+        name_without_project='{0}_{1}'.format(service, number))
+
+
+class CLIMainTestCase(unittest.TestCase):
+
+    def test_build_log_printer(self):
+        containers = [
+            mock_container('web', 1),
+            mock_container('web', 2),
+            mock_container('db', 1),
+            mock_container('other', 1),
+            mock_container('another', 1),
+        ]
+        service_names = ['web', 'db']
+        log_printer = build_log_printer(containers, service_names, True)
+        self.assertEqual(log_printer.containers, containers[:3])
+
+    def test_attach_to_logs(self):
+        project = mock.create_autospec(Project)
+        log_printer = mock.create_autospec(LogPrinter, containers=[])
+        service_names = ['web', 'db']
+        timeout = 12
+
+        with mock.patch('compose.cli.main.signal', autospec=True) as mock_signal:
+            attach_to_logs(project, log_printer, service_names, timeout)
+
+        mock_signal.signal.assert_called_once_with(mock_signal.SIGINT, mock.ANY)
+        log_printer.run.assert_called_once_with()
+        project.stop.assert_called_once_with(
+            service_names=service_names,
+            timeout=timeout)