1 files changed, 46 insertions, 0 deletions
diff --git a/sphinx/util/compat.py b/sphinx/util/compat.py
new file mode 100644
index 000000000..edd8cac61
--- /dev/null
+++ b/sphinx/util/compat.py
@@ -0,0 +1,46 @@
+# -*- coding: utf-8 -*-
+"""
+    sphinx.util.compat
+    ~~~~~~~~~~~~~~~~~~
+
+    modules for backward compatibility
+
+    :copyright: Copyright 2007-2018 by the Sphinx team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+import warnings
+
+from six import string_types, iteritems
+
+from sphinx.deprecation import RemovedInSphinx30Warning
+from sphinx.util import import_object
+
+if False:
+    # For type annotation
+    from typing import Any, Dict  # NOQA
+    from sphinx.application import Sphinx  # NOQA
+    from sphinx.config import Config  # NOQA
+
+
+def deprecate_source_parsers(app, config):
+    # type: (Sphinx, Config) -> None
+    if config.source_parsers:
+        warnings.warn('The config variable "source_parsers" is deprecated. '
+                      'Please use app.add_source_parser() API instead.',
+                      RemovedInSphinx30Warning)
+        for suffix, parser in iteritems(config.source_parsers):
+            if isinstance(parser, string_types):
+                parser = import_object(parser, 'source parser')  # type: ignore
+            app.add_source_parser(suffix, parser)
+
+
+def setup(app):
+    # type: (Sphinx) -> Dict[unicode, Any]
+    app.connect('config-inited', deprecate_source_parsers)
+
+    return {
+        'version': 'builtin',
+        'parallel_read_safe': True,
+        'parallel_write_safe': True,
+    }