Update the TypeError message and example in the unit test.

repo2docker/buildpacks/conda/__init__.py

@@ -141,7 +141,7 @@ class CondaBuildPack(BaseImage):
                     env = {}
                 # check if the env file has a dictionary not a list or other data structure.
                 if not isinstance(env, dict):
-                    raise TypeError("environment.yml should contain a dictionary. Got %r" % env)
+                    raise TypeError("environment.yml should contain a dictionary. Got %r" % type(env))
                 for dep in env.get('dependencies', []):
                     if not isinstance(dep, str):
                         continue

tests/test_env_yml.py

@@ -19,7 +19,8 @@ def test_empty_env_yml(tmpdir):
 def test_no_dict_env_yml(tmpdir):
     tmpdir.chdir()
     q = tmpdir.join("environment.yml")
-    q.write("list/n ,string")
+    q.write("numpy\n "
+            "matplotlib\n")
     bq = buildpacks.CondaBuildPack()
     with pytest.raises(TypeError):
         py_ver = bq.python_version