User:This, that and the other/subst and safesubst

is the only one to display as expected when transcluded and when subsituted.

Transclusion of template - no parameter
In this case, the desired output of the tests is AWWW.

Transclusion of template - with parameter
In this case, the desired output of the tests is YEAH.

Substitution of template - no parameter
In this case, the desired output is the text AWWW cleanly substituted into the page.

Start of template End of template
 * Parameter 1:.
 * Parameter 1 or nothing:.
 * "YEAH" if parameter 1 set, "AWWW" if parameter 1 not set :
 * The same  switch, but with   code: AWWW
 * The same  switch, but with   code: AWWW
 * The same  switch, but with   code: AWWW

Substitution of template - with parameter
In this case, the desired output of the tests is the text YEAH cleanly substituted into the page.

Start of template End of template
 * Parameter 1: Bonjour.
 * Parameter 1 or nothing: Bonjour.
 * "YEAH" if parameter 1 set, "AWWW" if parameter 1 not set :
 * The same  switch, but with   code: YEAH
 * The same  switch, but with   code: YEAH
 * The same  switch, but with   code: YEAH