check for error if conversation is the wrong type

tests/corpus/test_corpus.py

@@ -1,31 +1,33 @@
 import pytest
 from sktalk.corpus.corpus import Corpus
+from contextlib import nullcontext as does_not_raise
 
 class TestCorpus():
 
-    @pytest.mark.parametrize("conversations,metadata",
+    @pytest.mark.parametrize("conversations,metadata,error",
                              [
                                 ([], {"author": "Person",
-                                      "language": "french"}),
+                                      "language": "french"},
+                                      does_not_raise()),
                                 (None, {"author": "Person",
-                                      "language": "french"}),
-                                (None, {}),
-                                ([], {})
+                                      "language": "french"},
+                                      does_not_raise()),
+                                (None, {}, does_not_raise()),
+                                ([], {}, does_not_raise()),
+                                ("Not A Conversation", {}, pytest.raises(TypeError))
                              ])
-    def test_init(self, conversations, metadata):
-        corpus: Corpus = Corpus(conversations = conversations,
+    def test_init(self, conversations, metadata, error):
+        with error:
+            corpus: Corpus = Corpus(conversations = conversations,
                                 **metadata)
 
-        # check that a corpus object is created
-        assert isinstance(corpus, Corpus)
-        # corpus object has metadata (can be empty, but should be created)
-        assert isinstance(corpus.metadata, dict)
+            # check that a corpus object is created
+            assert isinstance(corpus, Corpus)
+            # corpus object has metadata (can be empty, but should be created)
+            assert isinstance(corpus.metadata, dict)
 
-        # corpus object has or has not (zero, one, multiple) conversations
-        # assert corpus.conversations == conversations
-        assert isinstance(corpus.conversations, list)
-        assert conversations is None or corpus.conversations == conversations
-
-
-        # initialize a corpus with conversation object that is not a conversation should fail
+            # corpus object has or has not (zero, one, multiple) conversations
+            # assert corpus.conversations == conversations
+            assert isinstance(corpus.conversations, list)
+            assert conversations is None or corpus.conversations == conversations