Add option to specify non-failing stuff

There is a new configuration option that allows listing what can fail
without aborting the whole compose. So far, only buildinstall, createiso
and liveimages phases react to this option.

Signed-off-by: Lubomír Sedlář <lsedlar@redhat.com>

tests/test_compose.py

@@ -0,0 +1,45 @@
+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
+
+import mock
+import unittest
+import os
+import sys
+import tempfile
+import shutil
+
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
+
+from pungi.compose import Compose
+
+
+class ComposeTestCase(unittest.TestCase):
+    def setUp(self):
+        self.tmp_dir = tempfile.mkdtemp()
+
+    def tearDown(self):
+        shutil.rmtree(self.tmp_dir)
+
+    @mock.patch('pungi.compose.ComposeInfo')
+    def test_can_fail(self, ci):
+        conf = {
+            'failable_deliverables': [
+                ('^.*$', {
+                    '*': ['buildinstall'],
+                    'i386': ['buildinstall', 'live', 'iso'],
+                }),
+            ]
+        }
+        compose = Compose(conf, self.tmp_dir)
+        variant = mock.Mock(uid='Server')
+
+        self.assertTrue(compose.can_fail(variant, 'x86_64', 'buildinstall'))
+        self.assertFalse(compose.can_fail(variant, 'x86_64', 'live'))
+        self.assertTrue(compose.can_fail(variant, 'i386', 'live'))
+
+        self.assertFalse(compose.can_fail(None, 'x86_64', 'live'))
+        self.assertTrue(compose.can_fail(None, 'i386', 'live'))
+
+
+if __name__ == "__main__":
+    unittest.main()