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/auevents.lua

@@ -57,6 +57,7 @@ return {
     'InsertLeave',            -- when leaving Insert mode
     'JobActivity',            -- when job sent some data
     'MenuPopup',              -- just before popup menu is displayed
+    'OptionSet',              -- after setting any option
     'QuickFixCmdPost',        -- after :make, :grep etc.
     'QuickFixCmdPre',         -- before :make, :grep etc.
     'QuitPre',                -- before :quit