How to write a regex in title case - regex

Question

I'm working with an SAP application called information steward and creating a rule where names will have to be in title case (ie each word is capitalized).
I've formulated the following rule:
BEGIN
IF(match_regex($name, '(^(\b[A-Z]\w*\s*)+$)', null)) RETURN TRUE;
ELSE RETURN FALSE;
END
Although it is successful it appears to accept inputs which should be identified as 'FALSE'. Please see the attached screenshot.
'TesT Name' and 'TEST NAME' should be FALSE but are instead passing under this regex.
Any help/guidance with the regex would be very useful.

Answer 1

The (^(\b[A-Z]\w*\s*)+$) regex presents a pattern that matches a string that fully matches:
^ - start of string
(\b[A-Z]\w*\s*)+ - 1 or more occurrences (due to (...)+) of
\b - a word boundary
[A-Z] - an uppercase ASCII letter
\w* - 0 or more letters/digits/underscores
\s* - 0+ whitespaces
$ - end of string.
As you see, it allows trailing whitespace, and \w matches what [A-Za-z0-9_] matches, i.e. it matches both lower- and uppercase letters.
You want to only match lowercase letters after initial uppercase ones, also allowing - and _ chars. You may use
^[A-Z][a-z0-9_-]*(\s+[A-Z][a-z0-9_-]*)*$
See the regex demo.
Details
^ - start of string anchor
[A-Z][a-z0-9_-]* - an uppercase letter followed with 0+ lowercase letters, digits, _ or - chars
(\s+[A-Z][a-z0-9_-]*)* - zero or more occurrences of:
\s+ - 1 or more whitespaces
[A-Z][a-z0-9_-]* - an uppercase letter followed with 0+ lowercase letters, digits, _ or - chars
$ - end of string.

Answer 2

I would write your regex as:
^[A-Z]\w*(?:\s+[A-Z]\w*)*$
This says to match a single word starting with a capital letter, then followed by one or more spaces and another word starting with a capital, this quantity zero or more times.
I phrase a matching word as starting with [A-Z] followed by \w*, meaning zero or more word characters. This allows for things like A to match.
Demo
Edit:
Based on the comments above, if you want some other character class to represent what follows the initial uppercase letter, then do that instead:
^[A-Z][something]*(?:\s+[A-Z][something]*)*$
where [something] is your character class.