Rename jinja_env_class

Inspired by #1056

flask/app.py

@@ -160,7 +160,7 @@ class Flask(_PackageBoundObject):
     #: The class that is used for the Jinja environment.
     #:
     #: .. versionadded:: 1.0
-    jinja_env_class = Environment
+    jinja_environment = Environment
 
     #: The class that is used for the :data:`~flask.g` instance.
     #:
@@ -685,7 +685,7 @@ class Flask(_PackageBoundObject):
                 options['auto_reload'] = self.config['TEMPLATES_AUTO_RELOAD']
             else:
                 options['auto_reload'] = self.debug
-        rv = self.jinja_env_class(self, **options)
+        rv = self.jinja_environment(self, **options)
         rv.globals.update(
             url_for=url_for,
             get_flashed_messages=get_flashed_messages,

tests/test_templating.py

@@ -367,7 +367,7 @@ def test_custom_jinja_env():
         pass
 
     class CustomFlask(flask.Flask):
-        jinja_env_class = CustomEnvironment
+        jinja_environment = CustomEnvironment
 
     app = CustomFlask(__name__)
     assert isinstance(app.jinja_env, CustomEnvironment)