Merge pull request #54 from lsst/tickets/DM-15158

Add tests of DataIdContainer and improve exception handling

COPYRIGHT

@@ -0,0 +1,6 @@
+2016-2018 Association of Universities for Research in Astronomy
+2015-2018 University of Washington
+2015-2018 The Trustees of Princeton University
+2017-2018 The Board of Trustees of the Leland Stanford Junior University, through SLAC National Accelerator Laboratory
+2016 University of Illinois Champaign-Urbana
+2011-2015 LSST Corporation

python/lsst/pipe/base/argumentParser.py

@@ -120,8 +120,9 @@ def castDataIds(self, butler):
             raise RuntimeError("Must call setDatasetType first")
         try:
             idKeyTypeDict = butler.getKeys(datasetType=self.datasetType, level=self.level)
-        except KeyError:
-            raise KeyError("Cannot get keys for datasetType %s at level %s" % (self.datasetType, self.level))
+        except KeyError as e:
+            msg = "Cannot get keys for datasetType %s at level %s: %s" % (self.datasetType, self.level)
+            raise KeyError(msg) from e
 
         for dataDict in self.idList:
             for key, strVal in dataDict.items():

tests/test_dataIdContainer.py

@@ -0,0 +1,66 @@
+# This file is part of pipe_base.
+#
+# Developed for the LSST Data Management System.
+# This product includes software developed by the LSST Project
+# (https://www.lsst.org).
+# See the COPYRIGHT file at the top-level directory of this distribution
+# for details of code ownership.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+"""Tests of the DataIdContainer class."""
+
+import unittest
+import unittest.mock
+
+import lsst.daf.persistence
+import lsst.utils.tests
+import lsst.pipe.base as pipeBase
+
+
+class DataIdContainerTestCase(lsst.utils.tests.TestCase):
+    def setUp(self):
+        self.container = pipeBase.DataIdContainer()
+        self.butler = unittest.mock.MagicMock(spec=lsst.daf.persistence.Butler)
+
+    def test_castDataIdsNoneDatasetType(self):
+        """Raise RuntimeError if we haven't set container.datasetType."""
+        with self.assertRaises(RuntimeError):
+            self.container.castDataIds(self.butler)
+
+    def test_makeDataRefListNoneDatasetType(self):
+        """Raise RuntimeError if we haven't set container.datasetType."""
+        with self.assertRaises(RuntimeError):
+            self.container.makeDataRefList(self.butler)
+
+    def test_castDataIdsRaiseKeyError(self):
+        """Test that castDataIds re-raises a butler.getKeys() exception."""
+        self.container.setDatasetType("nonsense!")
+        self.butler.getKeys.side_effect = KeyError
+        with self.assertRaises(KeyError) as cm:
+            self.container.castDataIds(self.butler)
+        self.assertIsInstance(cm.exception.__cause__, KeyError)
+
+
+class MyMemoryTestCase(lsst.utils.tests.MemoryTestCase):
+    pass
+
+
+def setup_module(module):
+    lsst.utils.tests.init()
+
+
+if __name__ == "__main__":
+    lsst.utils.tests.init()
+    unittest.main()