@@ -44,8 +44,12 @@ class BaseCommand:
         self.args['<command>'] = self.__class__.__name__.lower()
         self.command_args = command_args
 
-        self.molecule = core.Molecule(self.args)
-        self.main()
+        # allow us to reuse an existing molecule instance
+        if not molecule:
+            self.molecule = core.Molecule(self.args)
+            self.main()
+        else:
+            self.molecule = molecule
 
     def main(self):
         c = self.molecule._config
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#
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#  all copies or substantial portions of the Software.
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#  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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#  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
#  THE SOFTWARE.

import abc
import docopt

from molecule import core
from molecule import utilities


class InvalidHost(Exception):
    pass


class BaseCommand:
    __metaclass__ = abc.ABCMeta

    def __init__(self, command_args, args, molecule=False):
        """
        Initialize commands

        :param command_args: arguments of the command
        :param args: arguments from the CLI
        :param molecule: molecule instance
        """
        self.args = docopt.docopt(self.__doc__, argv=command_args)
        self.args['<command>'] = self.__class__.__name__.lower()
        self.command_args = command_args

        self.molecule = core.Molecule(self.args)
        self.main()

    def main(self):
        c = self.molecule._config
        if not c.molecule_file_exists():
            error = '\nUnable to find {}. Exiting.'
            utilities.logger.error(error.format(c.molecule_file))
            utilities.sysexit()
        self.molecule.main()

    @abc.abstractproperty
    def execute(self):
        pass

Would be nice to know the use case for this, and if it is even necessary. I would prefer to leave it out, unless we can duplicate a bug by it not being in.