allow running command builders (not on source files)

src/main/python/pybuilder/pluginhelper/external_command.py

@@ -17,7 +17,7 @@
 #   limitations under the License.
 
 from pybuilder.plugins.python.python_plugin_helper import execute_tool_on_source_files
-from pybuilder.utils import read_file
+from pybuilder.utils import read_file, execute_command
 
 
 class ExternalCommandResult(object):
@@ -63,6 +63,9 @@ def only_if_property_is_truthy(self, property_name):
     def as_string(self):
         return ' '.join(self.parts)
 
+    def run(self, outfile_name):
+        return execute_command(self.parts, outfile_name)
+
     def run_on_production_source_files(self, logger, include_test_sources=False, include_scripts=False):
         execution_result = execute_tool_on_source_files(project=self.project,
                                                         name=self.command_name,

src/unittest/python/external_command_tests.py

@@ -106,6 +106,12 @@ def setUp(self):
         self.command = ExternalCommandBuilder('command-name', self.project)
         self.command.use_argument('--foo').use_argument('--bar')
 
+    @patch("pybuilder.pluginhelper.external_command.execute_command")
+    def test_should_execute_external_command(self, execute_command):
+        self.command.run("any-outfile-name")
+
+        execute_command.assert_called_with(['command-name', '--foo', '--bar'], 'any-outfile-name')
+
     @patch('pybuilder.pluginhelper.external_command.read_file')
     @patch('pybuilder.pluginhelper.external_command.execute_tool_on_source_files')
     def test_should_execute_external_command_on_production_source_files(self, execution, read):