add test for list parameters

lib/spack/spack/test/config.py

@@ -72,6 +72,10 @@
     }
 }
 
+# Some Sample repo data
+repos_low = [ "/some/path" ]
+repos_high = [ "/some/other/path" ]
+
 class ConfigTest(MockPackagesTest):
 
     def setUp(self):
@@ -95,6 +99,12 @@ def check_config(self, comps, arch, *compiler_names):
                 actual = config[arch][key][c]
                 self.assertEqual(expected, actual)
 
+    def test_write_list_in_memory(self):
+        spack.config.update_config('repos', repos_low, 'test_low_priority')
+        spack.config.update_config('repos', repos_high, 'test_high_priority')
+        config = spack.config.get_config('repos')
+        self.assertEqual(config, repos_high+repos_low)
+
     def test_write_key_in_memory(self):
         # Write b_comps "on top of" a_comps.
         spack.config.update_config('compilers', a_comps, 'test_low_priority')