vim-patch:7.4.786

Problem:    It is not possible for a plugin to adjust to a changed setting.
Solution:   Add the OptionSet autocommand event. (Christian Brabandt)

537443018d

src/nvim/eval.h

@@ -108,6 +108,9 @@ enum {
     VV_PROGPATH,
     VV_COMMAND_OUTPUT,
     VV_COMPLETED_ITEM,
+    VV_OPTION_NEW,
+    VV_OPTION_OLD,
+    VV_OPTION_TYPE,
     VV_MSGPACK_TYPES,
     VV_LEN, /* number of v: vars */
 };