py*-pyqt6: Failed to Parse After Sync

[RobK88]

After the last sync on my old MacBook Pro running High Sierra, I see:

sudo port -v selfupdate
....
Adding subport p5.30-parallel-forkmanager
Adding subport p5.34-parallel-forkmanager
Adding subport p5.32-parallel-forkmanager
Failed to parse file python/py-pyqt6/Portfile with subport 'py39-pyqt6': can't read "qt6.version": can't read "qt_info()": no such element in array
Failed to parse file python/py-pyqt6/Portfile with subport 'py310-pyqt6': can't read "qt6.version": can't read "qt_info()": no such element in array
Failed to parse file python/py-pyqt6/Portfile with subport 'py311-pyqt6': can't read "qt6.version": can't read "qt_info()": no such element in array
Failed to parse file python/py-pyqt6/Portfile with subport 'py312-pyqt6': can't read "qt6.version": can't read "qt_info()": no such element in array

Total number of ports parsed:	577 
Ports successfully parsed:	573 
Ports failed:			4 
Up-to-date ports skipped:	38939


The ports tree has been updated.

1 port is outdated. Run 'port outdated' for details.
To upgrade your installed ports, you should run
  port upgrade outdated
bash-3.2$

[jmroot (Joshua Root)]

Looks like it's probably a qt6 portgroup issue.

[reneeotten (Renee Otten)]

I guess the issue is in the qt6_info-1.0.tcl PortGroup, more precisely in this function:

 89 proc qt6::version {} {
 90     array set qt_info [list {*}${qt6::available_versions}]
 91     return [lindex $qt_info([option qt6.base]) 0]

It's due to the fact that on systems older than macOS 10.15 there is no version of Qt 6 that will work and thus ${qt6::available_versions} is empty and making an array and extracting a value doesn't work. Unfortunately, I cannot reproduce/troubleshoot this easily since I don't have an macOS version where this issue manifests itself and my Tcl knowledge isn't sufficient to easily see how/where to resolve this. So I don't think I'll make progress on this anytime soon - fortunately it isn't a fatal issue; the port just doesn't parse for you but it would never install anything on these old systems anyway.

[jmroot (Joshua Root)]

You should just need to add a check that the array element in question exists, i.e. [info exists qt_info([option qt6.base])], and do something reasonable like returning an empty list otherwise.

[reneeotten (Renee Otten)]

In 89613f7c32763631c0ae86530f96ab73d9d16c6a/macports-ports (master):

qt6_info PG: fix qt.version for unsupported systems

Closes: #70620

[reneeotten (Renee Otten)]

thanks Josh - hopefully fixed now!