[MacPorts] #57865: mpbb fails parsing command line options if disk is full

[MacPorts]

#57865: mpbb fails parsing command line options if disk is full
---------------------------+---------------------
 Reporter:  ryandesign     |      Owner:  admin@…
     Type:  defect         |     Status:  new
 Priority:  Normal         |  Milestone:
Component:  buildbot/mpbb  |    Version:
 Keywords:                 |       Port:
---------------------------+---------------------
 If the disk is full, `mpbb` [https://build.macports.org/builders/ports-10
 .7_x86_64_legacy-builder/builds/91692/steps/cleanup/logs/stdio fails while
 parsing command line options]:

 {{{
 /opt/bblocal/var/buildworker/ports/build/mpbb/functions: line 46: cannot
 create temp file for here document: No space left on device
 /opt/bblocal/var/buildworker/ports/build/mpbb/functions: line 20:
 validopts[@]: unbound variable
 }}}

 Would be great if `mpbb cleanup` at least could work even if the disk is
 full, since this failure leaves the builder in a wedged state with no disk
 space available, causing subsequent builds to fail, requiring some manual
 cleanup and rescheduling of the failed builds.

 Lines 46-47 of [https://github.com/macports/mpbb/blob/master/functions
 functions] are:

 {{{
     IFS=, read -ra validopts <<<"$1"
     readonly validopts=("${validopts[@]/#/--}")
 }}}

 Apparently a here document (`<<<`) requires a temporary file. Could the
 options be parsed successfully without a heredoc?

-- 
Ticket URL: <https://trac.macports.org/ticket/57865>
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