Fix warning message when a container uses a non-json log driver

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

tests/unit/cli/log_printer_test.py

@@ -1,20 +1,31 @@
 from __future__ import absolute_import
 from __future__ import unicode_literals
 
-import os
-
+import mock
 import six
 
 from compose.cli.log_printer import LogPrinter
+from compose.cli.log_printer import wait_on_exit
+from compose.container import Container
 from tests import unittest
 
 
+def build_mock_container(reader):
+    return mock.Mock(
+        spec=Container,
+        name='myapp_web_1',
+        name_without_project='web_1',
+        has_api_logs=True,
+        attach=reader,
+        wait=mock.Mock(return_value=0),
+    )
+
+
 class LogPrinterTest(unittest.TestCase):
     def get_default_output(self, monochrome=False):
         def reader(*args, **kwargs):
             yield b"hello\nworld"
-
-        container = MockContainer(reader)
+        container = build_mock_container(reader)
         output = run_log_printer([container], monochrome=monochrome)
         return output
 
@@ -38,37 +49,39 @@ class LogPrinterTest(unittest.TestCase):
         def reader(*args, **kwargs):
             yield glyph.encode('utf-8') + b'\n'
 
-        container = MockContainer(reader)
+        container = build_mock_container(reader)
         output = run_log_printer([container])
         if six.PY2:
             output = output.decode('utf-8')
 
         self.assertIn(glyph, output)
 
+    def test_wait_on_exit(self):
+        exit_status = 3
+        mock_container = mock.Mock(
+            spec=Container,
+            name='cname',
+            wait=mock.Mock(return_value=exit_status))
+
+        expected = '{} exited with code {}\n'.format(mock_container.name, exit_status)
+        self.assertEqual(expected, wait_on_exit(mock_container))
+
+    def test_generator_with_no_logs(self):
+        mock_container = mock.Mock(
+            spec=Container,
+            has_api_logs=False,
+            log_driver='none',
+            name_without_project='web_1',
+            wait=mock.Mock(return_value=0))
+
+        output = run_log_printer([mock_container])
+        self.assertIn(
+            "WARNING: no logs are available with the 'none' log driver\n",
+            output
+        )
+
 
 def run_log_printer(containers, monochrome=False):
-    r, w = os.pipe()
-    reader, writer = os.fdopen(r, 'r'), os.fdopen(w, 'w')
-    printer = LogPrinter(containers, output=writer, monochrome=monochrome)
-    printer.run()
-    writer.close()
-    return reader.read()
-
-
-class MockContainer(object):
-    def __init__(self, reader):
-        self._reader = reader
-
-    @property
-    def name(self):
-        return 'myapp_web_1'
-
-    @property
-    def name_without_project(self):
-        return 'web_1'
-
-    def attach(self, *args, **kwargs):
-        return self._reader()
-
-    def wait(self, *args, **kwargs):
-        return 0
+    output = six.StringIO()
+    LogPrinter(containers, output=output, monochrome=monochrome).run()
+    return output.getvalue()