1 files changed, 85 insertions, 0 deletions
diff --git a/test/reader/test_chain.py b/test/reader/test_chain.py
new file mode 100644
index 0000000..901faa1
--- /dev/null
+++ b/test/reader/test_chain.py
@@ -0,0 +1,85 @@
+"""
+
+Part of the bsie test suite.
+A copy of the license is provided with the project.
+Author: Matthias Baumgartner, 2022
+"""
+# standard imports
+import logging
+import os
+import unittest
+
+# bsie imports
+from bsie.utils import errors
+import bsie.reader.path
+import bsie.reader.stat
+
+# objects to test
+from bsie.reader.chain import ReaderChain
+
+
+## code ##
+
+class TestReaderChain(unittest.TestCase):
+    def test_construct(self):
+        # subreaders are built
+        chain = ReaderChain(['bsie.reader.stat.Stat', 'bsie.reader.path.Path'], {})
+        self.assertIsInstance(chain, ReaderChain)
+        self.assertEqual(chain._children,
+            (bsie.reader.stat.Stat(), bsie.reader.path.Path()))
+        # subreaders that failed to build are omitted
+        with self.assertLogs(logging.getLogger('bsie.reader.chain'), logging.WARNING):
+            chain = ReaderChain(['bsie.reader.stat.Stat', 'bsie.reader.invalid.Invalid'], {})
+            self.assertEqual(chain._children, (bsie.reader.stat.Stat(), ))
+        with self.assertLogs(logging.getLogger('bsie.reader.chain'), logging.WARNING):
+            chain = ReaderChain(['bsie.reader.stat.Stat', 'bsie.reader.path.Invalid'], {})
+            self.assertEqual(chain._children, (bsie.reader.stat.Stat(), ))
+        # warning is issued if there are no subreaders
+        with self.assertLogs(logging.getLogger('bsie.reader.chain'), logging.WARNING):
+            chain = ReaderChain([], {})
+            self.assertEqual(chain._children, tuple())
+
+    def test_essentials(self):
+        chain = ReaderChain(['bsie.reader.stat.Stat', 'bsie.reader.path.Path'], {})
+        # identity
+        self.assertEqual(chain, chain)
+        self.assertEqual(hash(chain), hash(chain))
+        # comparison works across instances
+        self.assertEqual(chain,
+            ReaderChain(['bsie.reader.stat.Stat', 'bsie.reader.path.Path'], {}))
+        self.assertEqual(hash(chain),
+            hash(ReaderChain(['bsie.reader.stat.Stat', 'bsie.reader.path.Path'], {})))
+        # comparison respects subreaders
+        self.assertNotEqual(hash(chain),
+            hash(ReaderChain(['bsie.reader.path.Path'], {})))
+        self.assertNotEqual(hash(chain),
+            hash(ReaderChain(['bsie.reader.path.Path'], {})))
+        # comparison respects subreader order
+        self.assertNotEqual(chain,
+            ReaderChain(['bsie.reader.path.Path', 'bsie.reader.stat.Stat'], {}))
+        self.assertNotEqual(hash(chain),
+            hash(ReaderChain(['bsie.reader.path.Path', 'bsie.reader.stat.Stat'], {})))
+        # string representation
+        self.assertEqual(str(chain), 'ReaderChain(Stat, Path)')
+        self.assertEqual(repr(chain), 'ReaderChain((Stat(), Path()))')
+
+    def test_call(self):
+        chain = ReaderChain(['bsie.reader.stat.Stat', 'bsie.reader.path.Path'], {})
+        # chain first probes first child
+        self.assertEqual(chain(__file__), os.stat(__file__))
+        # chain probes second child if first one failes
+        self.assertEqual(chain(''), '')
+        self.assertEqual(chain('missing-file'), 'missing-file')
+
+        # chain raises a ReaderError if childs were exhausted
+        chain = ReaderChain(['bsie.reader.stat.Stat'], {})
+        # chain probes second child if first one failes
+        self.assertRaises(errors.ReaderError, chain, '')
+
+
+## main ##
+
+if __name__ == '__main__':
+    unittest.main()
+
+## EOF ##