diff --git a/cli/tests/data/dcos.toml b/cli/tests/data/dcos.toml
index 9d1d9d3..9e4e8e5 100644
--- a/cli/tests/data/dcos.toml
+++ b/cli/tests/data/dcos.toml
@@ -1,8 +1,8 @@
+[core]
+reporting = false
+email = "test@mail.com"
 [subcommand]
 pip_find_links = "../dist"
-[core]
-email = "test@mail.com"
-reporting = false
 [marathon]
 host = "localhost"
 port = 8080
diff --git a/cli/tests/integrations/cli/test_auth.py b/cli/tests/integrations/cli/test_auth.py
index 736520f..771dcab 100644
--- a/cli/tests/integrations/cli/test_auth.py
+++ b/cli/tests/integrations/cli/test_auth.py
@@ -8,7 +8,6 @@ from mock import Mock, patch
 
 
 def test_no_browser_auth():
-
     webbrowser.get = Mock(side_effect=webbrowser.Error())
     with patch('webbrowser.open') as op:
         _mock_dcos_run([util.which('dcos')], False)
diff --git a/cli/tests/integrations/cli/test_config.py b/cli/tests/integrations/cli/test_config.py
index 2770c0e..489cb32 100644
--- a/cli/tests/integrations/cli/test_config.py
+++ b/cli/tests/integrations/cli/test_config.py
@@ -6,7 +6,7 @@ import six
 from dcos.api import constants
 
 import pytest
-from common import exec_command
+from common import assert_command, exec_command
 
 
 @pytest.fixture
@@ -19,10 +19,7 @@ def env():
 
 
 def test_help():
-    returncode, stdout, stderr = exec_command(['dcos', 'config', '--help'])
-
-    assert returncode == 0
-    assert stdout == b"""Get and set DCOS CLI configuration properties
+    stdout = b"""Get and set DCOS CLI configuration properties
 
 Usage:
     dcos config --info
@@ -44,32 +41,24 @@ Positional Arguments:
     <name>           The name of the property
     <value>          The value of the property
 """
-    assert stderr == b''
+    assert_command(['dcos', 'config', '--help'],
+                   stdout=stdout)
 
 
 def test_info():
-    returncode, stdout, stderr = exec_command(['dcos', 'config', '--info'])
-
-    assert returncode == 0
-    assert stdout == b'Get and set DCOS CLI configuration properties\n'
-    assert stderr == b''
+    stdout = b'Get and set DCOS CLI configuration properties\n'
+    assert_command(['dcos', 'config', '--info'],
+                   stdout=stdout)
 
 
 def test_version():
-    returncode, stdout, stderr = exec_command(['dcos', 'config', '--version'])
-
-    assert returncode == 0
-    assert stdout == b'dcos-config version 0.1.0\n'
-    assert stderr == b''
+    stdout = b'dcos-config version 0.1.0\n'
+    assert_command(['dcos', 'config', '--version'],
+                   stdout=stdout)
 
 
 def test_list_property(env):
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'config', 'show'],
-        env)
-
-    assert returncode == 0
-    assert stdout == b"""core.email=test@mail.com
+    stdout = b"""core.email=test@mail.com
 core.reporting=False
 marathon.host=localhost
 marathon.port=8080
@@ -78,7 +67,9 @@ package.sources=['git://github.com/mesosphere/universe.git', \
 'https://github.com/mesosphere/universe/archive/master.zip']
 subcommand.pip_find_links=../dist
 """
-    assert stderr == b''
+    assert_command(['dcos', 'config', 'show'],
+                   stdout=stdout,
+                   env=env)
 
 
 def test_get_existing_string_property(env):
@@ -94,19 +85,17 @@ def test_get_missing_property(env):
 
 
 def test_get_top_property(env):
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'config', 'show', 'marathon'],
-        env)
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == (
+    stderr = (
         b"Property 'marathon' doesn't fully specify a value - "
         b"possible properties are:\n"
         b"marathon.host\n"
         b"marathon.port\n"
     )
 
+    assert_command(['dcos', 'config', 'show', 'marathon'],
+                   stderr=stderr,
+                   returncode=1)
+
 
 def test_set_existing_string_property(env):
     _set_value('marathon.host', 'newhost', env)
@@ -191,27 +180,25 @@ def test_prepend_list(env):
 
 
 def test_append_non_list(env):
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'config', 'append', 'marathon.host', 'new_uri'],
-        env)
+    stderr = (b"Append/Prepend not supported on 'marathon.host' "
+              b"properties - use 'dcos config set marathon.host new_uri'\n")
 
-    assert returncode == 1
-    assert stdout == b''
-    assert (stderr ==
-            b"Append/Prepend not supported on 'marathon.host' "
-            b"properties - use 'dcos config set marathon.host new_uri'\n")
+    assert_command(
+        ['dcos', 'config', 'append', 'marathon.host', 'new_uri'],
+        returncode=1,
+        stderr=stderr,
+        env=env)
 
 
 def test_prepend_non_list(env):
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'config', 'prepend', 'marathon.host', 'new_uri'],
-        env)
+    stderr = (b"Append/Prepend not supported on 'marathon.host' "
+              b"properties - use 'dcos config set marathon.host new_uri'\n")
 
-    assert returncode == 1
-    assert stdout == b''
-    assert (stderr ==
-            b"Append/Prepend not supported on 'marathon.host' "
-            b"properties - use 'dcos config set marathon.host new_uri'\n")
+    assert_command(
+        ['dcos', 'config', 'prepend', 'marathon.host', 'new_uri'],
+        returncode=1,
+        stderr=stderr,
+        env=env)
 
 
 def test_unset_property(env):
@@ -221,29 +208,27 @@ def test_unset_property(env):
 
 
 def test_unset_missing_property(env):
-    returncode, stdout, stderr = exec_command(
+    assert_command(
         ['dcos', 'config', 'unset', 'missing.property'],
-        env)
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b"Property 'missing.property' doesn't exist\n"
+        returncode=1,
+        stderr=b"Property 'missing.property' doesn't exist\n",
+        env=env)
 
 
 def test_unset_top_property(env):
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'config', 'unset', 'marathon'],
-        env)
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == (
+    stderr = (
         b"Property 'marathon' doesn't fully specify a value - "
         b"possible properties are:\n"
         b"marathon.host\n"
         b"marathon.port\n"
     )
 
+    assert_command(
+        ['dcos', 'config', 'unset', 'marathon'],
+        returncode=1,
+        stderr=stderr,
+        env=env)
+
 
 def test_unset_whole_list(env):
     _unset_value('package.sources', None, env)
@@ -268,73 +253,64 @@ def test_unset_list_index(env):
 
 
 def test_unset_outbound_index(env):
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'config', 'unset', '--index=3', 'package.sources'],
-        env)
+    stderr = (
+        b'Index (3) is out of bounds - possible values are '
+        b'between 0 and 1\n'
+    )
 
-    assert returncode == 1
-    assert stdout == b''
-    assert (stderr ==
-            b'Index (3) is out of bounds - possible values are '
-            b'between 0 and 1\n')
+    assert_command(
+        ['dcos', 'config', 'unset', '--index=3', 'package.sources'],
+        returncode=1,
+        stderr=stderr,
+        env=env)
 
 
 def test_unset_bad_index(env):
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'config', 'unset', '--index=number', 'package.sources'],
-        env)
+    stderr = b'Error parsing string as int\n'
 
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b'Error parsing string as int\n'
+    assert_command(
+        ['dcos', 'config', 'unset', '--index=number', 'package.sources'],
+        returncode=1,
+        stderr=stderr,
+        env=env)
 
 
 def test_unset_index_from_string(env):
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'config', 'unset', '--index=0', 'marathon.host'],
-        env)
+    stderr = b'Unsetting based on an index is only supported for lists\n'
 
-    assert returncode == 1
-    assert stdout == b''
-    assert (stderr ==
-            b'Unsetting based on an index is only supported for lists\n')
+    assert_command(
+        ['dcos', 'config', 'unset', '--index=0', 'marathon.host'],
+        returncode=1,
+        stderr=stderr,
+        env=env)
 
 
 def test_validate(env):
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'config', 'validate'],
-        env)
-
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
+    assert_command(['dcos', 'config', 'validate'],
+                   env=env)
 
 
 def test_validation_error(env):
     _unset_value('marathon.host', None, env)
 
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'config', 'validate'],
-        env)
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b"""Error: 'host' is a required property
+    stderr = b"""Error: 'host' is a required property
 Path: marathon
 Value: {"port": 8080}
 """
+    assert_command(['dcos', 'config', 'validate'],
+                   returncode=1,
+                   stderr=stderr,
+                   env=env)
 
     _set_value('marathon.host', 'localhost', env)
 
 
 def test_set_property_key(env):
-    returncode, stdout, stderr = exec_command(
+    assert_command(
         ['dcos', 'config', 'set', 'path.to.value', 'cool new value'],
-        env)
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b"'path' is not a dcos command.\n"
+        returncode=1,
+        stderr=b"'path' is not a dcos command.\n",
+        env=env)
 
 
 def test_set_missing_property(env):
@@ -350,33 +326,21 @@ def test_set_core_property(env):
 
 
 def _set_value(key, value, env):
-    returncode, stdout, stderr = exec_command(
+    assert_command(
         ['dcos', 'config', 'set', key, value],
-        env)
-
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
+        env=env)
 
 
 def _append_value(key, value, env):
-    returncode, stdout, stderr = exec_command(
+    assert_command(
         ['dcos', 'config', 'append', key, value],
-        env)
-
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
+        env=env)
 
 
 def _prepend_value(key, value, env):
-    returncode, stdout, stderr = exec_command(
+    assert_command(
         ['dcos', 'config', 'prepend', key, value],
-        env)
-
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
+        env=env)
 
 
 def _get_value(key, value, env):
@@ -399,11 +363,7 @@ def _unset_value(key, index, env):
     if index is not None:
         cmd.append('--index={}'.format(index))
 
-    returncode, stdout, stderr = exec_command(cmd, env)
-
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
+    assert_command(cmd, env=env)
 
 
 def _get_missing_value(key, env):
diff --git a/cli/tests/integrations/cli/test_dcos.py b/cli/tests/integrations/cli/test_dcos.py
index 488a496..3fca50f 100644
--- a/cli/tests/integrations/cli/test_dcos.py
+++ b/cli/tests/integrations/cli/test_dcos.py
@@ -2,7 +2,7 @@ import os
 
 from dcos.api import constants
 
-from common import exec_command
+from common import assert_command, exec_command
 
 
 def test_default():
@@ -29,10 +29,7 @@ Get detailed command description with 'dcos <command> --help'.
 
 
 def test_help():
-    returncode, stdout, stderr = exec_command(['dcos', '--help'])
-
-    assert returncode == 0
-    assert stdout == b"""\
+    stdout = b"""\
 Command line utility for the Mesosphere Datacenter Operating
 System (DCOS)
 
@@ -62,15 +59,14 @@ Environment Variables:
     DCOS_CONFIG                 This environment variable points to the
                                 location of the DCOS configuration file.
 """
-    assert stderr == b''
+
+    assert_command(['dcos', '--help'],
+                   stdout=stdout)
 
 
 def test_version():
-    returncode, stdout, stderr = exec_command(['dcos', '--version'])
-
-    assert returncode == 0
-    assert stdout == b'dcos version 0.1.0\n'
-    assert stderr == b''
+    assert_command(['dcos', '--version'],
+                   stdout=b'dcos version 0.1.0\n')
 
 
 def test_missing_dcos_config():
@@ -78,12 +74,13 @@ def test_missing_dcos_config():
         constants.PATH_ENV: os.environ[constants.PATH_ENV],
     }
 
-    returncode, stdout, stderr = exec_command(['dcos'], env=env)
+    stdout = (b"Environment variable 'DCOS_CONFIG' must be set "
+              b"to the DCOS config file.\n")
 
-    assert returncode == 1
-    assert stdout == (b"Environment variable 'DCOS_CONFIG' must be set "
-                      b"to the DCOS config file.\n")
-    assert stderr == b''
+    assert_command(['dcos'],
+                   stdout=stdout,
+                   returncode=1,
+                   env=env)
 
 
 def test_dcos_config_not_a_file():
@@ -92,12 +89,13 @@ def test_dcos_config_not_a_file():
         'DCOS_CONFIG': 'missing/file',
     }
 
-    returncode, stdout, stderr = exec_command(['dcos'], env=env)
+    stdout = (b"Environment variable 'DCOS_CONFIG' maps to "
+              b"'missing/file' and it is not a file.\n")
 
-    assert returncode == 1
-    assert stdout == (b"Environment variable 'DCOS_CONFIG' maps to "
-                      b"'missing/file' and it is not a file.\n")
-    assert stderr == b''
+    assert_command(['dcos'],
+                   returncode=1,
+                   stdout=stdout,
+                   env=env)
 
 
 def test_log_level_flag():
@@ -117,11 +115,11 @@ def test_capital_log_level_flag():
 
 
 def test_invalid_log_level_flag():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', '--log-level=blah', 'config', '--info'])
+    stdout = (b"Log level set to an unknown value 'blah'. Valid "
+              b"values are ['debug', 'info', 'warning', 'error', "
+              b"'critical']\n")
 
-    assert returncode == 1
-    assert stdout == (b"Log level set to an unknown value 'blah'. Valid "
-                      b"values are ['debug', 'info', 'warning', 'error', "
-                      b"'critical']\n")
-    assert stderr == b''
+    assert_command(
+        ['dcos', '--log-level=blah', 'config', '--info'],
+        returncode=1,
+        stdout=stdout)
diff --git a/cli/tests/integrations/cli/test_help.py b/cli/tests/integrations/cli/test_help.py
index 82149a5..91eae05 100644
--- a/cli/tests/integrations/cli/test_help.py
+++ b/cli/tests/integrations/cli/test_help.py
@@ -1,11 +1,8 @@
-from common import exec_command
+from common import assert_command
 
 
 def test_help():
-    returncode, stdout, stderr = exec_command(['dcos', 'help', '--help'])
-
-    assert returncode == 0
-    assert stdout == b"""Display command line usage information
+    stdout = b"""Display command line usage information
 
 Usage:
     dcos help --info
@@ -16,30 +13,22 @@ Options:
     --info     Show a short description of this subcommand
     --version  Show version
 """
-    assert stderr == b''
+    assert_command(['dcos', 'help', '--help'],
+                   stdout=stdout)
 
 
 def test_info():
-    returncode, stdout, stderr = exec_command(['dcos', 'help', '--info'])
-
-    assert returncode == 0
-    assert stdout == b'Display command line usage information\n'
-    assert stderr == b''
+    assert_command(['dcos', 'help', '--info'],
+                   stdout=b'Display command line usage information\n')
 
 
 def test_version():
-    returncode, stdout, stderr = exec_command(['dcos', 'help', '--version'])
-
-    assert returncode == 0
-    assert stdout == b'dcos-help version 0.1.0\n'
-    assert stderr == b''
+    assert_command(['dcos', 'help', '--version'],
+                   stdout=b'dcos-help version 0.1.0\n')
 
 
 def test_list():
-    returncode, stdout, stderr = exec_command(['dcos', 'help'])
-
-    assert returncode == 0
-    assert stdout == """\
+    stdout = """\
 Command line utility for the Mesosphere Datacenter Operating
 System (DCOS). The Mesosphere DCOS is a distributed operating
 system built around Apache Mesos. This utility provides tools
@@ -55,4 +44,6 @@ Available DCOS commands:
 
 Get detailed command description with 'dcos <command> --help'.
 """.encode('utf-8')
-    assert stderr == b''
+
+    assert_command(['dcos', 'help'],
+                   stdout=stdout)
diff --git a/cli/tests/integrations/cli/test_marathon.py b/cli/tests/integrations/cli/test_marathon.py
index ba9485f..659a78f 100644
--- a/cli/tests/integrations/cli/test_marathon.py
+++ b/cli/tests/integrations/cli/test_marathon.py
@@ -1,13 +1,10 @@
 import json
 
-from common import exec_command
+from common import assert_command, exec_command
 
 
 def test_help():
-    returncode, stdout, stderr = exec_command(['dcos', 'marathon', '--help'])
-
-    assert returncode == 0
-    assert stdout == b"""Deploy and manage applications on the DCOS
+    stdout = b"""Deploy and manage applications on the DCOS
 
 Usage:
     dcos marathon --config-schema
@@ -62,24 +59,18 @@ Positional arguments:
                                 value must be the '=' character. E.g. cpus=2.0
     <task-id>                   The task id
 """
-    assert stderr == b''
+    assert_command(['dcos', 'marathon', '--help'],
+                   stdout=stdout)
 
 
 def test_version():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', '--version'])
-
-    assert returncode == 0
-    assert stdout == b'dcos-marathon version 0.1.0\n'
-    assert stderr == b''
+    assert_command(['dcos', 'marathon', '--version'],
+                   stdout=b'dcos-marathon version 0.1.0\n')
 
 
 def test_info():
-    returncode, stdout, stderr = exec_command(['dcos', 'marathon', '--info'])
-
-    assert returncode == 0
-    assert stdout == b'Deploy and manage applications on the DCOS\n'
-    assert stderr == b''
+    assert_command(['dcos', 'marathon', '--info'],
+                   stdout=b'Deploy and manage applications on the DCOS\n')
 
 
 def test_empty_list():
@@ -93,13 +84,8 @@ def test_add_app():
 
 
 def test_optional_add_app():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'add',
-            'tests/data/marathon/zero_instance_sleep.json'])
-
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
+    assert_command(['dcos', 'marathon', 'app', 'add',
+                    'tests/data/marathon/zero_instance_sleep.json'])
 
     _list_apps('zero-instance-app')
     _remove_app('zero-instance-app')
@@ -126,13 +112,11 @@ def test_add_existing_app():
     _add_app('tests/data/marathon/zero_instance_sleep.json')
 
     with open('tests/data/marathon/zero_instance_sleep_v2.json') as fd:
-        returncode, stdout, stderr = exec_command(
-            ['dcos', 'marathon', 'app', 'add'],
-            stdin=fd)
-
-        assert returncode == 1
-        assert stdout == b"Application '/zero-instance-app' already exists\n"
-        assert stderr == b''
+        stdout = b"Application '/zero-instance-app' already exists\n"
+        assert_command(['dcos', 'marathon', 'app', 'add'],
+                       returncode=1,
+                       stdout=stdout,
+                       stdin=fd)
 
     _remove_app('zero-instance-app')
 
@@ -170,14 +154,11 @@ def test_show_missing_relative_app_version():
         'zero-instance-app',
         'tests/data/marathon/update_zero_instance_sleep.json')
 
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'show',
-            '--app-version=-2', 'zero-instance-app'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert (stderr ==
-            b"Application 'zero-instance-app' only has 2 version(s).\n")
+    stderr = b"Application 'zero-instance-app' only has 2 version(s).\n"
+    assert_command(['dcos', 'marathon', 'app', 'show',
+                    '--app-version=-2', 'zero-instance-app'],
+                   returncode=1,
+                   stderr=stderr)
 
     _remove_app('zero-instance-app')
 
@@ -206,15 +187,13 @@ def test_show_bad_app_version():
         'zero-instance-app',
         'tests/data/marathon/update_zero_instance_sleep.json')
 
-    returncode, stdout, stderr = exec_command(
+    stderr = (b'Error: Invalid format: "20:39:32.972Z" is malformed at '
+              b'":39:32.972Z"\n')
+    assert_command(
         ['dcos', 'marathon', 'app', 'show', '--app-version=20:39:32.972Z',
-         'zero-instance-app'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert (stderr ==
-            (b'Error: Invalid format: "20:39:32.972Z" is malformed at '
-             b'":39:32.972Z"\n'))
+         'zero-instance-app'],
+        returncode=1,
+        stderr=stderr)
 
     _remove_app('zero-instance-app')
 
@@ -225,24 +204,20 @@ def test_show_bad_relative_app_version():
         'zero-instance-app',
         'tests/data/marathon/update_zero_instance_sleep.json')
 
-    returncode, stdout, stderr = exec_command(
+    assert_command(
         ['dcos', 'marathon', 'app', 'show',
-            '--app-version=2', 'zero-instance-app'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert (stderr == b"Relative versions must be negative: 2\n")
+         '--app-version=2', 'zero-instance-app'],
+        returncode=1,
+        stderr=b"Relative versions must be negative: 2\n")
 
     _remove_app('zero-instance-app')
 
 
 def test_start_missing_app():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'start', 'missing-id'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b"Error: App '/missing-id' does not exist\n"
+    assert_command(
+        ['dcos', 'marathon', 'app', 'start', 'missing-id'],
+        returncode=1,
+        stderr=b"Error: App '/missing-id' does not exist\n")
 
 
 def test_start_app():
@@ -255,24 +230,18 @@ def test_start_already_started_app():
     _add_app('tests/data/marathon/zero_instance_sleep.json')
     _start_app('zero-instance-app')
 
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'start', 'zero-instance-app'])
-
-    assert returncode == 1
-    assert (stdout ==
-            b"Application 'zero-instance-app' already started: 1 instances.\n")
-    assert stderr == b''
+    stdout = b"Application 'zero-instance-app' already started: 1 instances.\n"
+    assert_command(['dcos', 'marathon', 'app', 'start', 'zero-instance-app'],
+                   returncode=1,
+                   stdout=stdout)
 
     _remove_app('zero-instance-app')
 
 
 def test_stop_missing_app():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'stop', 'missing-id'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b"Error: App '/missing-id' does not exist\n"
+    assert_command(['dcos', 'marathon', 'app', 'stop', 'missing-id'],
+                   returncode=1,
+                   stderr=b"Error: App '/missing-id' does not exist\n")
 
 
 def test_stop_app():
@@ -294,24 +263,18 @@ def test_stop_app():
 def test_stop_already_stopped_app():
     _add_app('tests/data/marathon/zero_instance_sleep.json')
 
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'stop', 'zero-instance-app'])
-
-    assert returncode == 1
-    assert (stdout ==
-            b"Application 'zero-instance-app' already stopped: 0 instances.\n")
-    assert stderr == b''
+    stdout = b"Application 'zero-instance-app' already stopped: 0 instances.\n"
+    assert_command(['dcos', 'marathon', 'app', 'stop', 'zero-instance-app'],
+                   returncode=1,
+                   stdout=stdout)
 
     _remove_app('zero-instance-app')
 
 
 def test_update_missing_app():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'update', 'missing-id'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b"Error: App '/missing-id' does not exist\n"
+    assert_command(['dcos', 'marathon', 'app', 'update', 'missing-id'],
+                   stderr=b"Error: App '/missing-id' does not exist\n",
+                   returncode=1)
 
 
 def test_update_missing_field():
@@ -372,25 +335,19 @@ def test_update_app_from_stdin():
 def test_restarting_stopped_app():
     _add_app('tests/data/marathon/zero_instance_sleep.json')
 
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'restart', 'zero-instance-app'])
-
-    assert returncode == 1
-    assert stdout == (
-        b"Unable to perform rolling restart of application '"
-        b"/zero-instance-app' because it has no running tasks\n")
-    assert stderr == b''
+    stdout = (b"Unable to perform rolling restart of application '"
+              b"/zero-instance-app' because it has no running tasks\n")
+    assert_command(['dcos', 'marathon', 'app', 'restart', 'zero-instance-app'],
+                   returncode=1,
+                   stdout=stdout)
 
     _remove_app('zero-instance-app')
 
 
 def test_restarting_missing_app():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'restart', 'missing-id'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b"Error: App '/missing-id' does not exist\n"
+    assert_command(['dcos', 'marathon', 'app', 'restart', 'missing-id'],
+                   returncode=1,
+                   stderr=b"Error: App '/missing-id' does not exist\n")
 
 
 def test_restarting_app():
@@ -410,22 +367,17 @@ def test_restarting_app():
 
 
 def test_list_version_missing_app():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'version', 'list', 'missing-id'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b"Error: App '/missing-id' does not exist\n"
+    assert_command(
+        ['dcos', 'marathon', 'app', 'version', 'list', 'missing-id'],
+        returncode=1,
+        stderr=b"Error: App '/missing-id' does not exist\n")
 
 
 def test_list_version_negative_max_count():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'version', 'list',
-            'missing-id', '--max-count=-1'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b'Maximum count must be a positive number: -1\n'
+    assert_command(['dcos', 'marathon', 'app', 'version', 'list',
+                    'missing-id', '--max-count=-1'],
+                   returncode=1,
+                   stderr=b'Maximum count must be a positive number: -1\n')
 
 
 def test_list_version_app():
@@ -479,13 +431,10 @@ def test_list_deployment_app():
 
 
 def test_rollback_missing_deployment():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'deployment', 'rollback', 'missing-deployment'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert (stderr ==
-            b'Error: DeploymentPlan missing-deployment does not exist\n')
+    assert_command(
+        ['dcos', 'marathon', 'deployment', 'rollback', 'missing-deployment'],
+        returncode=1,
+        stderr=b'Error: DeploymentPlan missing-deployment does not exist\n')
 
 
 def test_rollback_deployment():
@@ -513,12 +462,7 @@ def test_stop_deployment():
     _start_app('zero-instance-app', 3)
     result = _list_deployments(1, 'zero-instance-app')
 
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'deployment', 'stop', result[0]['id']])
-
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
+    assert_command(['dcos', 'marathon', 'deployment', 'stop', result[0]['id']])
 
     _list_deployments(0)
 
@@ -613,11 +557,8 @@ def test_bad_configuration():
     assert returncode == 0
     assert stderr == b''
 
-    returncode, stdout, stderr = exec_command(
+    assert_command(
         ['dcos', 'config', 'set', 'marathon.port', str(int(port) + 1)])
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
 
     returncode, stdout, stderr = exec_command(
         ['dcos', 'marathon', 'app', 'list'])
@@ -654,12 +595,7 @@ def _list_apps(app_id=None):
 
 
 def _remove_app(app_id):
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'marathon', 'app', 'remove', app_id])
-
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
+    assert_command(['dcos', 'marathon', 'app', 'remove', app_id])
 
     # Let's make sure that we don't return until the deployment has finished
     result = _list_deployments(None, app_id)
@@ -711,13 +647,8 @@ def _start_app(app_id, instances=None):
 
 def _update_app(app_id, file_path):
     with open(file_path) as fd:
-        returncode, stdout, stderr = exec_command(
-            ['dcos', 'marathon', 'app', 'update', app_id],
-            stdin=fd)
-
-        assert returncode == 0
-        assert stdout == b''
-        assert stderr == b''
+        assert_command(['dcos', 'marathon', 'app', 'update', app_id],
+                       stdin=fd)
 
 
 def _list_versions(app_id, expected_count, max_count=None):
diff --git a/cli/tests/integrations/cli/test_package.py b/cli/tests/integrations/cli/test_package.py
index 2deba63..22a7810 100644
--- a/cli/tests/integrations/cli/test_package.py
+++ b/cli/tests/integrations/cli/test_package.py
@@ -8,10 +8,7 @@ from common import assert_command, exec_command
 
 
 def test_package():
-    returncode, stdout, stderr = exec_command(['dcos', 'package', '--help'])
-
-    assert returncode == 0
-    assert stdout == b"""Install and manage DCOS software packages
+    stdout = b"""Install and manage DCOS software packages
 
 Usage:
     dcos package --config-schema
@@ -55,35 +52,28 @@ Configuration:
       "git://github.com/mesosphere/universe.git"
     ]
 """
-    assert stderr == b''
+    assert_command(['dcos', 'package', '--help'],
+                   stdout=stdout)
 
 
 def test_info():
-    returncode, stdout, stderr = exec_command(['dcos', 'package', '--info'])
-
-    assert returncode == 0
-    assert stdout == b'Install and manage DCOS software packages\n'
-    assert stderr == b''
+    assert_command(['dcos', 'package', '--info'],
+                   stdout=b'Install and manage DCOS software packages\n')
 
 
 def test_version():
-    returncode, stdout, stderr = exec_command(['dcos', 'package', '--version'])
-
-    assert returncode == 0
-    assert stdout == b'dcos-package version 0.1.0\n'
-    assert stderr == b''
+    assert_command(['dcos', 'package', '--version'],
+                   stdout=b'dcos-package version 0.1.0\n')
 
 
 def test_sources_list():
-    returncode, stdout, stderr = exec_command(['dcos', 'package', 'sources'])
-
-    assert returncode == 0
-    assert stdout == b"""c3f1a0df1d2068e6b11d40224f5e500d3183a97e \
+    stdout = b"""c3f1a0df1d2068e6b11d40224f5e500d3183a97e \
 git://github.com/mesosphere/universe.git
 f4ba0923d14eb75c1c0afca61c2adf9b2b355bd5 \
 https://github.com/mesosphere/universe/archive/master.zip
 """
-    assert stderr == b''
+    assert_command(['dcos', 'package', 'sources'],
+                   stdout=stdout)
 
 
 def test_update_without_validation():
@@ -108,20 +98,13 @@ def test_update_with_validation():
 
 
 def test_describe_nonexistent():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'package', 'describe', 'xyzzy'])
-
-    assert returncode == 1
-    assert stdout == b'Package [xyzzy] not found\n'
-    assert stderr == b''
+    assert_command(['dcos', 'package', 'describe', 'xyzzy'],
+                   stdout=b'Package [xyzzy] not found\n',
+                   returncode=1)
 
 
 def test_describe():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'package', 'describe', 'mesos-dns'])
-
-    assert returncode == 0
-    assert stdout == b"""\
+    stdout = b"""\
 {
   "description": "DNS-based service discovery for Mesos.",
   "maintainer": "support@mesosphere.io",
@@ -139,7 +122,8 @@ tutorial-gce.html",
   "website": "http://mesosphere.github.io/mesos-dns"
 }
 """
-    assert stderr == b''
+    assert_command(['dcos', 'package', 'describe', 'mesos-dns'],
+                   stdout=stdout)
 
 
 def test_bad_install():
@@ -163,16 +147,11 @@ def test_install():
 
 
 def test_package_metadata():
-    returncode, stdout, stderr = exec_command(['dcos',
-                                               'package',
-                                               'install',
-                                               'helloworld'])
-
-    assert returncode == 0
-    assert stdout == b"""Installing package [helloworld] version [0.1.0]
+    stdout = b"""Installing package [helloworld] version [0.1.0]
 Installing CLI subcommand for package [helloworld]
 """
-    assert stderr == b''
+    assert_command(['dcos', 'package', 'install', 'helloworld'],
+                   stdout=stdout)
 
     # test marathon labels
     expected_metadata = b"""eyJkZXNjcmlwdGlvbiI6ICJFeGFtcGxlIERDT1MgYXBwbGljYX\
@@ -231,12 +210,7 @@ wLjEuMCJdfQ=="""
         assert six.b(f.read()) == b'0'
 
     # uninstall helloworld
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'package', 'uninstall', 'helloworld'])
-
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
+    assert_command(['dcos', 'package', 'uninstall', 'helloworld'])
 
 
 def test_install_with_id():
@@ -254,14 +228,12 @@ with app id [dns-2]\n"""
 
 
 def test_install_missing_package():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'package', 'install', 'missing-package'])
-
-    assert returncode == 1
-    assert stdout == b''
-    assert stderr == b"""Package [missing-package] not found
+    stderr = b"""Package [missing-package] not found
 You may need to run 'dcos package update' to update your repositories
 """
+    assert_command(['dcos', 'package', 'install', 'missing-package'],
+                   returncode=1,
+                   stderr=stderr)
 
 
 def test_uninstall_with_id():
@@ -281,26 +253,16 @@ def test_uninstall_missing():
 
 
 def test_uninstall_subcommand():
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'package', 'install', 'helloworld'])
-
-    assert returncode == 0
-    assert stdout == b"""Installing package [helloworld] version [0.1.0]
+    stdout = b"""Installing package [helloworld] version [0.1.0]
 Installing CLI subcommand for package [helloworld]
 """
-    assert stderr == b''
+    assert_command(['dcos', 'package', 'install', 'helloworld'],
+                   stdout=stdout)
 
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'package', 'uninstall', 'helloworld'])
-    assert returncode == 0
-    assert stdout == b''
-    assert stderr == b''
+    assert_command(['dcos', 'package', 'uninstall', 'helloworld'])
 
-    returncode, stdout, stderr = exec_command(
-        ['dcos', 'subcommand', 'list'])
-    assert returncode == 0
-    assert stdout == b'[]\n'
-    assert stderr == b''
+    assert_command(['dcos', 'subcommand', 'list'],
+                   stdout=b'[]\n')
 
 
 def test_list_installed():