Allow tests to influence env

Author: kevin-bates

jupyter_server/tests/launchserver.py

@@ -90,6 +90,17 @@ def request(cls, verb, path, **kwargs):
             **kwargs)
         return response
 
+    @classmethod
+    def get_patch_env(cls):
+        return {
+            'HOME': cls.home_dir,
+            'PYTHONPATH': os.pathsep.join(sys.path),
+            'JUPYTER_NO_CONFIG': '1', # needed in the future
+            'JUPYTER_CONFIG_DIR' : cls.config_dir,
+            'JUPYTER_DATA_DIR' : cls.data_dir,
+            'JUPYTER_RUNTIME_DIR': cls.runtime_dir,
+        }
+
     @classmethod
     def get_argv(cls):
         return []
@@ -111,14 +122,7 @@ def tmp(*parts):
         config_dir = cls.config_dir = tmp('config')
         runtime_dir = cls.runtime_dir = tmp('runtime')
         cls.root_dir = tmp('root_dir')
-        cls.env_patch = patch.dict('os.environ', {
-            'HOME': cls.home_dir,
-            'PYTHONPATH': os.pathsep.join(sys.path),
-            'JUPYTER_NO_CONFIG': '1', # needed in the future
-            'JUPYTER_CONFIG_DIR' : config_dir,
-            'JUPYTER_DATA_DIR' : data_dir,
-            'JUPYTER_RUNTIME_DIR': runtime_dir,
-        })
+        cls.env_patch = patch.dict('os.environ', cls.get_patch_env())
         cls.env_patch.start()
         cls.path_patch = patch.multiple(
             jupyter_core.paths,