Change extension setup() return value to a dictionary of metadata.

This makes it possible to introduce more metadata values later.

1 files changed, 1 insertions, 1 deletions

diff --git a/sphinx/ext/pngmath.py b/sphinx/ext/pngmath.py
index ee108d166..342b1bd8a 100644
--- a/sphinx/ext/pngmath.py
+++ b/sphinx/ext/pngmath.py
@@ -246,4 +246,4 @@ def setup(app):
     app.add_config_value('pngmath_latex_preamble', '', 'html')
     app.add_config_value('pngmath_add_tooltips', True, 'html')
     app.connect('build-finished', cleanup_tempdir)
-    return sphinx.__version__
+    return {'version': sphinx.__version__}