Add default_role contextmanager to enable default-role temporarily

sphinx/environment/__init__.py

@@ -26,13 +26,11 @@ from six.moves import cPickle as pickle
 
 from docutils.utils import Reporter, get_source_line, normalize_language_tag
 from docutils.utils.smartquotes import smartchars
-from docutils.parsers.rst import roles
-from docutils.parsers.rst.languages import en as english
 from docutils.frontend import OptionParser
 
 from sphinx import addnodes
 from sphinx.io import read_doc
-from sphinx.util import logging
+from sphinx.util import logging, rst
 from sphinx.util import get_matching_docs, FilenameUniqDict, status_iterator
 from sphinx.util.nodes import is_translatable
 from sphinx.util.osutil import SEP, ensuredir
@@ -80,8 +78,6 @@ default_settings = {
 ENV_VERSION = 52 + (sys.version_info[0] - 2)
 
 
-dummy_reporter = Reporter('', 4, 4)
-
 versioning_conditions = {
     'none': False,
     'text': is_translatable,
@@ -696,16 +692,7 @@ class BuildEnvironment(object):
         if path.isfile(docutilsconf):
             self.note_dependency(docutilsconf)
 
-        with sphinx_domains(self):
-            if self.config.default_role:
-                role_fn, messages = roles.role(self.config.default_role, english,
-                                               0, dummy_reporter)
-                if role_fn:
-                    roles._roles[''] = role_fn
-                else:
-                    logger.warning('default role %s not found', self.config.default_role,
-                                   location=docname)
-
+        with sphinx_domains(self), rst.default_role(docname, self.config.default_role):
             codecs.register_error('sphinx', self.warn_and_replace)  # type: ignore
             doctree = read_doc(self.app, self, self.doc2path(docname))
 
@@ -745,7 +732,6 @@ class BuildEnvironment(object):
         # cleanup
         self.temp_data.clear()
         self.ref_context.clear()
-        roles._roles.pop('', None)  # if a document has set a local default role
 
         self.write_doctree(docname, doctree)
 

sphinx/util/rst.py

@@ -8,12 +8,37 @@
     :copyright: Copyright 2007-2017 by the Sphinx team, see AUTHORS.
     :license: BSD, see LICENSE for details.
 """
+from __future__ import absolute_import
 
 import re
+from contextlib import contextmanager
+
+from docutils.parsers.rst import roles
+from docutils.parsers.rst.languages import en as english
+from docutils.utils import Reporter
+
+from sphinx.util import logging
 
 symbols_re = re.compile(r'([!-/:-@\[-`{-~])')
+logger = logging.getLogger(__name__)
 
 
 def escape(text):
     # type: (unicode) -> unicode
     return symbols_re.sub(r'\\\1', text)  # type: ignore
+
+
+@contextmanager
+def default_role(docname, name):
+    # type: (unicode, unicode) -> None
+    if name:
+        dummy_reporter = Reporter('', 4, 4)
+        role_fn, _ = roles.role(name, english, 0, dummy_reporter)
+        if role_fn:
+            roles._roles[''] = role_fn
+        else:
+            logger.warning('default role %s not found', name, location=docname)
+
+    yield
+
+    roles._roles.pop('', None)  # if a document has set a local default role