Merge remote-tracking branch 'richtja/loader_incom_v4'

Signed-off-by: NCleber Rosa <crosa@redhat.com>

avocado/core/loader.py

@@ -23,6 +23,7 @@ import os
 import re
 import shlex
 import sys
+import warnings
 from enum import Enum
 
 from ..utils import stacktrace
@@ -123,6 +124,10 @@ class TestLoaderProxy:
         if external_runner:
             self.register_plugin(ExternalLoader)
             key = "{}.loaders".format(subcommand)
+            if set(config[key]) != {'file', '@DEFAULT'}:
+                warnings.warn("The loaders and external-runner are incompatible."
+                              "The values in loaders will be ignored.",
+                              RuntimeWarning)
             config[key] = ["external:{}".format(external_runner)]
         else:
             # Add (default) file loader if not already registered

docs/source/guides/user/chapters/introduction.rst

@@ -215,6 +215,10 @@ But now consider the following example::
 This effectively makes `/bin/curl` an "external test runner", responsible for
 trying to fetch those URLs, and reporting PASS or FAIL for each of them.
 
+.. warning:: The external runner is incompatible with loaders from
+   :ref:`test-loaders`. If you use external runner and loader together
+   the job will use the external runner and ignore the loader.
+
 Runner outputs
 --------------
 

docs/source/guides/user/chapters/loaders.rst

-Undestanding the test discovery (Avocado Loaders)
-=================================================
+.. _test-loaders:
+
+Understanding the test discovery (Avocado Loaders)
+==================================================
 
 In this section you can learn how tests are being discovered and how to
 customize this process.

selftests/functional/test_loader.py

@@ -9,7 +9,8 @@ import unittest
 from avocado.core import exit_codes
 from avocado.utils import process, script
 
-from .. import AVOCADO, BASEDIR, TestCaseTmpDir, skipOnLevelsInferiorThan
+from .. import (AVOCADO, BASEDIR, TestCaseTmpDir, skipOnLevelsInferiorThan,
+                skipUnlessPathExists)
 
 AVOCADO_TEST_OK = """#!/usr/bin/env python
 from avocado import Test
@@ -296,6 +297,30 @@ class LoaderTestFunctional(TestCaseTmpDir):
                     b"SIMPLE       examples/tests/failtest.sh\n")
         self.assertEqual(expected, result.stdout)
 
+    @skipUnlessPathExists('/bin/sh')
+    def test_loader_and_external_runner_incompatibility(self):
+        """
+        Check if the user is inform about incompatibility between loader and
+        external_runner.
+        """
+        test_script = script.TemporaryScript('simpletest.sh', SIMPLE_TEST,
+                                             'avocado_loader_test',
+                                             mode=self.MODE_0775)
+        test_script.save()
+
+        cmd = ("%s run --loaders=FOO "
+               "--external-runner=/bin/sh %s") % (AVOCADO, test_script.path)
+        result = process.run(cmd)
+        expected_warning = ("The loaders and external-runner are incompatible."
+                            "The values in loaders will be ignored.")
+        self.assertIn(expected_warning, result.stderr_text)
+
+        cmd = "%s run --external-runner=/bin/sh %s" % (AVOCADO,
+                                                       test_script.path)
+        result = process.run(cmd)
+        self.assertNotIn(expected_warning, result.stderr_text)
+
+        test_script.remove()
 
 if __name__ == '__main__':
     unittest.main()