fix issue #280 namedtuple erorring in error generation on safe_dump

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2 files changed, 16 insertions, 2 deletions

diff --git a/_test/test_issues.py b/_test/test_issues.py
index 721f3fe..d5913f6 100644
--- a/_test/test_issues.py
+++ b/_test/test_issues.py
@@ -560,8 +560,22 @@ class TestIssues:
         """
         d = round_trip(inp)  # NOQA
 
+    def test_issue_280(self):
+        from ruamel.yaml import YAML
+        from ruamel.yaml.representer import RepresenterError
+        from collections import namedtuple
+        from sys import stdout
+        T = namedtuple('T', ('a', 'b'))
+        t = T(1, 2)
+        yaml = YAML()
+        with pytest.raises(RepresenterError, match='cannot represent'):
+            yaml.dump({'t': t}, stdout)
+
 #    @pytest.mark.xfail(strict=True, reason='bla bla', raises=AssertionError)
 #    def test_issue_ xxx(self):
 #        inp = """
 #        """
 #        d = round_trip(inp)  # NOQA
+
+
+   
diff --git a/_test/test_z_data.py b/_test/test_z_data.py
index 99810aa..f4e47cf 100644
--- a/_test/test_z_data.py
+++ b/_test/test_z_data.py
@@ -170,7 +170,7 @@ class TestYAMLData(object):
             yaml_version = d.get('yaml_version')
             if 'python' in d:
                 if not check_python_version(d['python']):
-                    pytest.skip("unsupported version")
+                    pytest.skip('unsupported version')
             idx += 1
         data = output = confirm = python = None
         for doc in docs[idx:]:
@@ -230,7 +230,7 @@ def check_python_version(match, current=None):
         # assert m[0].isdigit()
         # assert m[-1].isdigit()
         m = [int(x) for x in m.split('.')]
-        current_len = current[:len(m)]
+        current_len = current[: len(m)]
         # print(m, current, current_len)
         if minimal:
             if current_len >= m: