Created attachment 3260 [details]
BoolPtg.java (new file to support boolean token group)

Created attachment 3261 [details]
Patch Ptg.java to use BoolPtg.java

Committers, please review the patch and decide whether to add it to HEAD.

can you supply a unit test for these components as well?  Also you may want to
patch FormulaParser to add write support.  Thanks!

Created attachment 3263 [details]
Patch FormulaParser to use BoolPtg

FormulaParser is not much fun to work with, but I've done my best.  Now how do 
I go about writing a testcase?  I modeled BoolPtg after IntPtg, so the IntPtg 
test case would be the logical starting place.  But I can't find one for 
IntPtg, or any other Ptg.

Created attachment 3281 [details]
Add 2 new test cases to  TestFormulaParser

applied.  

In the future please put new files in directory preserving archives with context
relative to jakarta-poi.  (zip/tar.gz/tar.bz)  Please label their type in the
description (I'm a bad guesser).  Patches should be created relative to
jakarta-poi (and preserve the path).  thanks.

Please also add the appropriate tests to
src/testcases/org/apache/poi/hssf/usermodel/TestFormulas.java
(basically that they can be read and written and read from the file properly)

You bring up a good point about the PTGs.  The PTGs were actually part of an
earlier prototype of formula support that I began November of last year.  I did
not think it would actually end up in the real thing, but I guess Avik found
them useful.  Probably about 50% or more of the HSSF was written in that time
period.  We do not yet have an official policy regarding unit tests being
required, but I know at least I will vote -1 to release any new code as
"production" until the unit tests are written.  Old code is "grandfathered" in
and we'll add unit tests as time permits or bugs necessitate.

So With that in mind, how to write a testcase.  Well thats pretty simple. 
create a file called TestBoolPtg in
src/testcases/org/apache/poi/hssf/record/formula/.  Create a testBla() function
for each piece of functionality you want to test.  At minimum you should test
that the inputs yeild the expected results.  So construct an instance of BoolPtg
the way formula parser would and test that the results are what you would expect
(all properties, etc).  Then construct it as Ptg would and check the results. 
Its best to check all the common properties as they should be used.

Thank you for your contribution.