sphinx.ext.jsmath should be emit an math extension conlict error

1 files changed, 5 insertions, 1 deletions

diff --git a/sphinx/ext/jsmath.py b/sphinx/ext/jsmath.py
index ff77c2d1b..f36e12fed 100644
--- a/sphinx/ext/jsmath.py
+++ b/sphinx/ext/jsmath.py
@@ -56,7 +56,11 @@ def builder_inited(app):
 
 
 def setup(app):
-    mathbase_setup(app, (html_visit_math, None), (html_visit_displaymath, None))
+    try:
+        mathbase_setup(app, (html_visit_math, None), (html_visit_displaymath, None))
+    except ExtensionError:
+        raise ExtensionError('sphinx.ext.jsmath: other math package is already loaded')
+
     app.add_config_value('jsmath_path', '', False)
     app.connect('builder-inited', builder_inited)
     return {'version': sphinx.__display_version__, 'parallel_read_safe': True}