[MacPorts] #32090: python27 +universal: destroot fails if py27-xml is installed non-universal

[MacPorts]

#32090: python27 +universal: destroot fails if py27-xml is installed non-universal
----------------------------------+-----------------------------------------
 Reporter:  cdiehl@…              |       Owner:  jwa@…            
     Type:  defect                |      Status:  new              
 Priority:  Normal                |   Milestone:                   
Component:  ports                 |     Version:  2.0.3            
 Keywords:                        |        Port:  python27 py27-xml
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Comment(by software@…):

 FYI,

 I encountered a somewhat similar issue. While the problem is slightly
 different, the resolution posted by vloodo above works just as well in
 this case.

 In my case, I wanted to replace `python27` with `python27 +ucs4`. I had
 py27-xml installed at the time I was doing the replace. This lead to the
 following error during the destroot phase:

 {{{
 DYLD_FRAMEWORK_PATH=/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/Python-2.7.2:
 ../python.exe ./scripts/BuildApplet.py \
                 --destroot
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/destroot"
 \
 --python=/opt/local/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python
 \
                 --output
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/destroot/Applications/MacPorts/Python
 2.7/Build Applet.app" \
                 ./scripts/BuildApplet.py
 Traceback (most recent call last):
   File "./scripts/BuildApplet.py", line 156, in <module>
     main()
   File "./scripts/BuildApplet.py", line 36, in main
     buildapplet()
   File "./scripts/BuildApplet.py", line 123, in buildapplet
     progress=verbose, destroot=destroot)
   File
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/Python-2.7.2/Lib
 /plat-mac/buildtools.py", line 122, in process
     copy_codefragment, raw, others, filename, destroot)
   File
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/Python-2.7.2/Lib
 /plat-mac/buildtools.py", line 151, in process_common
     is_update, raw, others, filename, destroot)
   File
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/Python-2.7.2/Lib
 /plat-mac/buildtools.py", line 332, in process_common_macho
     builder.plist = plistlib.Plist.fromFile(plistname)
   File
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/Python-2.7.2/Lib/plistlib.py",
 line 345, in fromFile
     rootObject = readPlist(pathOrFile)
   File
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/Python-2.7.2/Lib/plistlib.py",
 line 78, in readPlist
     rootObject = p.parse(pathOrFile)
   File
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/Python-2.7.2/Lib/plistlib.py",
 line 401, in parse
     from xml.parsers.expat import ParserCreate
   File
 "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7
 /site-packages/_xmlplus/parsers/expat.py", line 4, in <module>
     from pyexpat import *
 ImportError:
 dlopen(/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7
 /site-packages/_xmlplus/parsers/pyexpat.so, 2): Symbol not found:
 _PyUnicodeUCS2_Decode
   Referenced from:
 /opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7
 /site-packages/_xmlplus/parsers/pyexpat.so
   Expected in: flat namespace
  in
 /opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7
 /site-packages/_xmlplus/parsers/pyexpat.so
 make[1]: *** [install_BuildApplet] Error 1
 make[1]: Leaving directory
 `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/Python-2.7.2/Mac'
 make: *** [frameworkinstallapps] Error 2
 make: Leaving directory
 `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_python27/python27/work/Python-2.7.2'
 }}}

 In short, destroot is calling some script called ./scripts/BuildApplet.py
 to compile .py to .pyc or .pyo files. (Building at the destroot phase is
 indeed ugly; you can blame that on Python).

 This script somehow imports site-packages, including py27-xml. py27-xml
 apparently uses a pyexpat.so shared object which is compiled against
 Python's C API. This fails if the C API is changes between Python builds.
 In my case, it was looking for the _PyUnicodeUCS2_Decode symbol, but a
 wide Pythone build (+ucs4) will not contain the UCS2 stuff, hence
 pyexpat.so fails.

 As for a solution -- it seems that making sure py27-xml is deactivated
 during the destroot phase of Python27 solves the problem, exactly as
 described by vloodo above:

 Please let me know if I should file this as separate bug report.

-- 
Ticket URL: <https://trac.macports.org/ticket/32090#comment:11>
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