handle only subports install files

[Ryan Schmidt]

On Mar 19, 2012, at 12:36, Joshua Root wrote:

> On 2012-3-20 04:32 , Bradley Giesbrecht wrote:
>> Does anyone have an example of a better way to handle the primary port not installing files?
>> 
>> Portfile:
>> ...
>> name mysql-connector-cpp
>> if {$subport == $name} {
>>   pre-fetch {
>>       ui_msg "Stub port: Choose one of \
>>           mysql5-connector-cpp, \
>>           mysql55-connector-cpp, \
>>           mariadb-connector-cpp, \
>>           percona-connector-cpp.
>>           "
>>       return
>>   }
>> }
>> ...
> 
> "Don't do that?" There's no point creating a port that can't be installed.

No, this is a totally valid question that I've had too.

The python portgroup has this problem with its py-foo ports; they serve no purpose; the user should not install them; the user should install the specific versioned subport. The python portgroup solves this by making py-foo a stub port that installs just a readme, and declares a dependency on one of the subports.

Same with the perl5 portgroup, and the new unified php portgroup, and with ports like VillainousStyle.

It might be nice if MacPorts could automatically tell the user not to install undeclared subports. That's the reason why I'm trying to declare every usable subport, i.e. why I make changes like this:

https://trac.macports.org/changeset/90954