1 files changed, 33 insertions, 1 deletions
diff --git a/tests/unit/errors_test.py b/tests/unit/errors_test.py
index b78af4e..9678669 100644
--- a/tests/unit/errors_test.py
+++ b/tests/unit/errors_test.py
@@ -2,8 +2,10 @@ import unittest
 
 import requests
 
-from docker.errors import (APIError, DockerException,
+from docker.errors import (APIError, ContainerError, DockerException,
                            create_unexpected_kwargs_error)
+from .fake_api import FAKE_CONTAINER_ID, FAKE_IMAGE_ID
+from .fake_api_client import make_fake_client
 
 
 class APIErrorTest(unittest.TestCase):
@@ -77,6 +79,36 @@ class APIErrorTest(unittest.TestCase):
         assert err.is_client_error() is True
 
 
+class ContainerErrorTest(unittest.TestCase):
+    def test_container_without_stderr(self):
+        """The massage does not contain stderr"""
+        client = make_fake_client()
+        container = client.containers.get(FAKE_CONTAINER_ID)
+        command = "echo Hello World"
+        exit_status = 42
+        image = FAKE_IMAGE_ID
+        stderr = None
+
+        err = ContainerError(container, exit_status, command, image, stderr)
+        msg = ("Command '{}' in image '{}' returned non-zero exit status {}"
+               ).format(command, image, exit_status, stderr)
+        assert str(err) == msg
+
+    def test_container_with_stderr(self):
+        """The massage contains stderr"""
+        client = make_fake_client()
+        container = client.containers.get(FAKE_CONTAINER_ID)
+        command = "echo Hello World"
+        exit_status = 42
+        image = FAKE_IMAGE_ID
+        stderr = "Something went wrong"
+
+        err = ContainerError(container, exit_status, command, image, stderr)
+        msg = ("Command '{}' in image '{}' returned non-zero exit status {}: "
+               "{}").format(command, image, exit_status, stderr)
+        assert str(err) == msg
+
+
 class CreateUnexpectedKwargsErrorTest(unittest.TestCase):
     def test_create_unexpected_kwargs_error_single(self):
         e = create_unexpected_kwargs_error('f', {'foo': 'bar'})