avocado.job: Always add JSON and Xunit outputs to job dir

As specified in the requirements meeting, always have Xunit and
JSON outputs written to the results dir. The basic idea is to
enable any output plugins specified in the cmd line, the Xunit
and JSON compulsorily, and in the end, if there are no output
plugins requested in the command line, enable human output.
Signed-off-by: NLucas Meneghel Rodrigues <lmr@redhat.com>

avocado/job.py

@@ -17,6 +17,7 @@
 Module that describes a sequence of automated test operations.
 """
 
+import argparse
 import imp
 import logging
 import multiprocessing
@@ -35,6 +36,8 @@ from avocado.utils import archive
 from avocado import multiplex_config
 from avocado import test
 from avocado import result
+from avocado.plugins import xunit
+from avocado.plugins import jsonresult
 
 _NEW_ISSUE_LINK = 'https://github.com/avocado-framework/avocado/issues/new'
 
@@ -214,12 +217,40 @@ class Job(object):
                     self.result_proxy.add_output_plugin(result_plugin)
 
     def _make_test_result(self):
+        """
+        Set up output plugins.
+
+        The basic idea behind the output plugins is:
+
+        * If there are any active output plugins, use them
+        * Always add Xunit and JSON plugins outputting to files inside the
+          results dir
+        * If at the end we only have 2 output plugins (Xunit and JSON), we can
+          add the human output plugin.
+        """
         if self.args:
+            # If there are any active output plugins, let's use them
             self._set_output_plugins()
 
-        if not self.result_proxy.output_plugins:
-            default_plugin = result.HumanTestResult(self.output_manager, self.args)
-            self.result_proxy.add_output_plugin(default_plugin)
+        # Setup the xunit plugin to output to the debug directory
+        xunit_file = os.path.join(self.debugdir, 'results.xml')
+        args = argparse.Namespace()
+        args.xunit_output = xunit_file
+        xunit_plugin = xunit.xUnitTestResult(self.output_manager, args)
+        self.result_proxy.add_output_plugin(xunit_plugin)
+
+        # Setup the json plugin to output to the debug directory
+        json_file = os.path.join(self.debugdir, 'results.json')
+        args = argparse.Namespace()
+        args.json_output = json_file
+        json_plugin = jsonresult.JSONTestResult(self.output_manager, args)
+        self.result_proxy.add_output_plugin(json_plugin)
+
+        # If there are no active output plugins besides xunit and json,
+        # set up the human output.
+        if len(self.result_proxy.output_plugins) == 2:
+            human_plugin = result.HumanTestResult(self.output_manager, self.args)
+            self.result_proxy.add_output_plugin(human_plugin)
 
     def _run(self, urls=None, multiplex_file=None):
         """