hgext/sparse.py

--- a/hgext/sparse.py	Thu Jul 06 12:14:12 2017 -0700
+++ b/hgext/sparse.py	Thu Jul 06 12:06:37 2017 -0700
@@ -110,6 +110,8 @@
     _setupcommit(ui)
 
 def extsetup(ui):
+    sparse.enabled = True
+
     _setupclone(ui)
     _setuplog(ui)
     _setupadd(ui)