new unit test for StatusError (minor)

tests/test_allgo.py

@@ -18,6 +18,23 @@ else:
 import allgo  # I need to modify constant
 from allgo import *
 
+# ================================================
+class TestStatusError:
+
+    REF_MSG = "whatever, an error message."
+
+    @pytest.fixture
+    def response(self):
+        m = Mock()
+        m.json.return_value = \
+            { 'error': self.REF_MSG }
+        return m
+
+    @pytest.mark.dbg
+    def test_msg(self, response):
+        err = StatusError(42, response)
+        assert self.REF_MSG == err.msg
+
 
 # ================================================
 @pytest.fixture(scope="module")