Refactor parsing by docutils

sphinx/environment/__init__.py

@@ -24,8 +24,6 @@ from collections import defaultdict
 from six import BytesIO, itervalues, class_types, next
 from six.moves import cPickle as pickle
 
-from docutils.io import NullOutput
-from docutils.core import Publisher
 from docutils.utils import Reporter, get_source_line, normalize_language_tag
 from docutils.utils.smartquotes import smartchars
 from docutils.parsers.rst import roles
@@ -33,9 +31,7 @@ from docutils.parsers.rst.languages import en as english
 from docutils.frontend import OptionParser
 
 from sphinx import addnodes
-from sphinx.io import (
-    SphinxStandaloneReader, SphinxDummySourceClass, SphinxDummyWriter, SphinxFileInput
-)
+from sphinx.io import read_doc
 from sphinx.util import logging
 from sphinx.util import get_matching_docs, FilenameUniqDict, status_iterator
 from sphinx.util.nodes import is_translatable
@@ -711,22 +707,7 @@ class BuildEnvironment(object):
                                    location=docname)
 
             codecs.register_error('sphinx', self.warn_and_replace)  # type: ignore
-
-            # publish manually
-            reader = SphinxStandaloneReader(self.app,
-                                            parsers=self.app.registry.get_source_parsers())
-            src_path = self.doc2path(docname)
-            source = SphinxFileInput(app, self, source=None, source_path=src_path,
-                                     encoding=self.config.source_encoding)
-            pub = Publisher(reader=reader,
-                            writer=SphinxDummyWriter(),
-                            source_class=SphinxDummySourceClass,
-                            destination=NullOutput())
-            pub.set_components(None, 'restructuredtext', None)
-            pub.process_programmatic_settings(None, self.settings, None)
-            pub.set_source(source, src_path)
-            pub.publish()
-            doctree = pub.document
+            doctree = read_doc(self.app, self, self.doc2path(docname))
 
         # post-processing
         for domain in itervalues(self.domains):

sphinx/io.py

@@ -8,7 +8,8 @@
     :copyright: Copyright 2007-2017 by the Sphinx team, see AUTHORS.
     :license: BSD, see LICENSE for details.
 """
-from docutils.io import FileInput
+from docutils.io import FileInput, NullOutput
+from docutils.core import Publisher
 from docutils.readers import standalone
 from docutils.writers import UnfilteredWriter
 from six import string_types, text_type, iteritems
@@ -185,3 +186,21 @@ class SphinxFileInput(FileInput):
             if self.env.config.rst_prolog:
                 data = self.env.config.rst_prolog + '\n' + data
         return docinfo + data
+
+
+def read_doc(app, env, filename):
+    """Parse a document and convert to doctree."""
+    # type: (Sphinx, BuildEnvironment, unicode) -> nodes.document
+    reader = SphinxStandaloneReader(app, parsers=app.registry.get_source_parsers())
+    source = SphinxFileInput(app, env, source=None, source_path=filename,
+                             encoding=env.config.source_encoding)
+
+    pub = Publisher(reader=reader,
+                    writer=SphinxDummyWriter(),
+                    source_class=SphinxDummySourceClass,
+                    destination=NullOutput())
+    pub.set_components(None, 'restructuredtext', None)
+    pub.process_programmatic_settings(None, env.settings, None)
+    pub.set_source(source, filename)
+    pub.publish()
+    return pub.document