Detach managers on pickling environment

sphinx/application.py

@@ -293,6 +293,7 @@ class Sphinx(object):
                 self.env = BuildEnvironment.frompickle(
                     self.srcdir, self.config, path.join(self.doctreedir, ENV_PICKLE_FILENAME))
                 self.env.set_warnfunc(self.warn)
+                self.env.init_managers()
                 self.env.domains = {}
                 for domain in self.domains.keys():
                     # this can raise if the data version doesn't fit

sphinx/environment/__init__.py

@@ -111,6 +111,7 @@ class BuildEnvironment(object):
         del self.config.values
         domains = self.domains
         del self.domains
+        managers = self.detach_managers()
         # remove potentially pickling-problematic values from config
         for key, val in list(vars(self.config).items()):
             if key.startswith('_') or \
@@ -121,6 +122,7 @@ class BuildEnvironment(object):
         with open(filename, 'wb') as picklefile:
             pickle.dump(self, picklefile, pickle.HIGHEST_PROTOCOL)
         # reset attributes
+        self.attach_managers(managers)
         self.domains = domains
         self.config.values = values
         self.set_warnfunc(warnfunc)
@@ -205,14 +207,26 @@ class BuildEnvironment(object):
         # attributes of "any" cross references
         self.ref_context = {}
 
+        self.managers = {}
         self.init_managers()
 
     def init_managers(self):
-        self.managers = {}
+        managers = {}
         for manager_class in [IndexEntries, Toctree]:
-            manager = manager_class(self)
-            self.managers[manager.name] = manager
-            setattr(self, manager.name, manager)
+            managers[manager_class.name] = manager_class(self)
+        self.attach_managers(managers)
+
+    def attach_managers(self, managers):
+        for name, manager in iteritems(managers):
+            self.managers[name] = manager
+            manager.attach(self)
+
+    def detach_managers(self):
+        managers = self.managers
+        self.managers = {}
+        for _, manager in iteritems(managers):
+            manager.detach(self)
+        return managers
 
     def set_warnfunc(self, func):
         self._warnfunc = func

sphinx/environment/managers/__init__.py

@@ -17,6 +17,16 @@ class EnvironmentManager(object):
     def __init__(self, env):
         self.env = env
 
+    def attach(self, env):
+        self.env = env
+        if self.name:
+            setattr(env, self.name, self)
+
+    def detach(self, env):
+        self.env = None
+        if self.name:
+            delattr(env, self.name)
+
     def clear_doc(self, docname):
         raise NotImplementedError