1 files changed, 45 insertions, 2 deletions
diff --git a/pbr/tests/base.py b/pbr/tests/base.py
index 09bd642..e017b06 100644
--- a/pbr/tests/base.py
+++ b/pbr/tests/base.py
@@ -47,6 +47,7 @@ import sys
 import fixtures
 import testresources
 import testtools
+from testtools import content
 
 from pbr import options
 
@@ -147,6 +148,48 @@ class BaseTestCase(testtools.TestCase, testresources.ResourcedTestCase):
         return result
 
 
+class CapturedSubprocess(fixtures.Fixture):
+    """Run a process and capture its output.
+
+    :attr stdout: The output (a string).
+    :attr stderr: The standard error (a string).
+    :attr returncode: The return code of the process.
+
+    Note that stdout and stderr are decoded from the bytestrings subprocess
+    returns using error=replace.
+    """
+
+    def __init__(self, label, *args, **kwargs):
+        """Create a CapturedSubprocess.
+
+        :param label: A label for the subprocess in the test log. E.g. 'foo'.
+        :param *args: The *args to pass to Popen.
+        :param **kwargs: The **kwargs to pass to Popen.
+        """
+        super(CapturedSubprocess, self).__init__()
+        self.label = label
+        self.args = args
+        self.kwargs = kwargs
+        self.kwargs['stderr'] = subprocess.PIPE
+        self.kwargs['stdin'] = subprocess.PIPE
+        self.kwargs['stdout'] = subprocess.PIPE
+
+    def setUp(self):
+        super(CapturedSubprocess, self).setUp()
+        proc = subprocess.Popen(*self.args, **self.kwargs)
+        out, err = proc.communicate()
+        self.out = out.decode('utf-8', 'replace')
+        self.err = err.decode('utf-8', 'replace')
+        self.addDetail(self.label + '-stdout', content.text_content(self.out))
+        self.addDetail(self.label + '-stderr', content.text_content(self.err))
+        self.returncode = proc.returncode
+        if proc.returncode:
+            raise AssertionError('Failed process %s' % proc.returncode)
+        self.addCleanup(delattr, self, 'out')
+        self.addCleanup(delattr, self, 'err')
+        self.addCleanup(delattr, self, 'returncode')
+
+
 def _run_cmd(args, cwd):
     """Run the command args in cwd.
 
@@ -158,8 +201,8 @@ def _run_cmd(args, cwd):
         args, stdin=subprocess.PIPE, stdout=subprocess.PIPE,
         stderr=subprocess.PIPE, cwd=cwd)
     streams = tuple(s.decode('latin1').strip() for s in p.communicate())
-    for content in streams:
-        print(content)
+    for stream_content in streams:
+        print(stream_content)
     return (streams) + (p.returncode,)