Move subp into its own module. (#416)

This was painful, but it finishes a TODO from cloudinit/subp.py.

It moves the following from util to subp:
  ProcessExecutionError
  subp
  which
  target_path

I moved subp_blob_in_tempfile into cc_chef, which is its only caller.
That saved us from having to deal with it using write_file
and temp_utils from subp (which does not import any cloudinit things now).

It is arguable that 'target_path' could be moved to a 'path_utils' or
something, but in order to use it from subp and also from utils,
we had to get it out of utils.

1 files changed, 2 insertions, 2 deletions

diff --git a/tests/unittests/test_distros/test_generic.py b/tests/unittests/test_distros/test_generic.py
index 02b334e3..6b6c1566 100644
--- a/tests/unittests/test_distros/test_generic.py
+++ b/tests/unittests/test_distros/test_generic.py
@@ -245,7 +245,7 @@ class TestGenericDistro(helpers.FilesystemMockingTestCase):
         for d_name in ("ubuntu", "rhel"):
             cls = distros.fetch(d_name)
             d = cls(d_name, {}, None)
-            with mock.patch("cloudinit.util.subp") as m_subp:
+            with mock.patch("cloudinit.subp.subp") as m_subp:
                 d.expire_passwd("myuser")
             m_subp.assert_called_once_with(["passwd", "--expire", "myuser"])
 
@@ -253,7 +253,7 @@ class TestGenericDistro(helpers.FilesystemMockingTestCase):
         """Test FreeBSD.expire_passwd uses the pw command."""
         cls = distros.fetch("freebsd")
         d = cls("freebsd", {}, None)
-        with mock.patch("cloudinit.util.subp") as m_subp:
+        with mock.patch("cloudinit.subp.subp") as m_subp:
             d.expire_passwd("myuser")
         m_subp.assert_called_once_with(
             ["pw", "usermod", "myuser", "-p", "01-Jan-1970"])