patch 7.4.2230
Problem:    There is no equivalent of 'smartcase' for a tag search.
Solution:   Add value "followscs" and "smart" to 'tagcase'. (Christian
            Brabandt, closes #712) Turn tagcase test into new style.
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 738367d..c531168 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -7417,6 +7417,9 @@
 	By default, tag searches are case-sensitive.  Case is ignored when
 	'ignorecase' is set and 'tagcase' is "followic", or when 'tagcase' is
 	"ignore".
+	Also when 'tagcase' is "followscs" and 'smartcase' is set, or
+	'tagcase' is "smart", and the pattern contains only lowercase
+	characters.
 
 	When 'tagbsearch' is off, tags searching is slower when a full match
 	exists, but faster when no full match exists.  Tags in unsorted tags
@@ -7435,8 +7438,10 @@
 	This option specifies how case is handled when searching the tags
 	file:
 	   followic	Follow the 'ignorecase' option
+	   followscs    Follow the 'smartcase' and 'ignorecase' options
 	   ignore	Ignore case
 	   match	Match case
+	   smart	Ignore case unless an upper case letter is used
 
 						*'taglength'* *'tl'*
 'taglength' 'tl'	number	(default 0)