[MacPorts] #61019: mpbb: Remove failcache entry if port is already installed

[MacPorts]

#61019: mpbb: Remove failcache entry if port is already installed
---------------------------+------------------------
 Reporter:  ryandesign     |      Owner:  ryandesign
     Type:  enhancement    |     Status:  assigned
 Priority:  Normal         |  Milestone:
Component:  buildbot/mpbb  |    Version:
 Keywords:  haspatch       |       Port:
---------------------------+------------------------
 We had an unusual problem where a failcache entry didn't get deleted upon
 a successful build.

 What happened was that
 [https://build.macports.org/builders/ports-10.13_x86_64-builder/builds/88311
 libsdl built fine] but an error occurred during activation so the build
 was marked as failed. I
 [https://build.macports.org/builders/ports-10.13_x86_64-builder/builds/89833
 forced another build of libsdl] which succeeded and distributed the
 previously built archive. The install-port part of the build didn't have
 to do anything; it just printed:

 {{{
 libsdl already installed, nothing to do
 }}}

 So even though the archive was now distributed, the failcache still
 considered the port unbuildable.

 Maybe mpbb should clear the failcache entry when the port was already
 installed (see patch).

 On the other hand, in this case, the failure of libsdl to activate was due
 to a problem with the tzb2 archive (#61018), and distributing that broken
 archive isn't helpful.

-- 
Ticket URL: <https://trac.macports.org/ticket/61019>
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