Fixing referenced before assignment

This is the error message which appears without the change:

'''
[INFO]:    # Downloading recipes
[INFO]:    Downloading qt5
[DEBUG]:   -> running mkdir -p /home/thopiekar/.local/share/python-for-android/packages/qt5
[INFO]:    -> directory context /home/thopiekar/.local/share/python-for-android/packages/qt5
[DEBUG]:   -> running basename http://download.qt.io/official_releases/qt/5.7/5.7.0/single/qt-everywhere-opensource-src-5.7.0.tar.gz
[DEBUG]:        qt-everywhere-opensource-src-5.7.0.tar.gz
[WARNING]: Should check headers here! Skipping for now.
Downloading qt5 from http://download.qt.io/official_releases/qt/5.7/5.7.0/single/qt-everywhere-opensource-src-5.7.0.tar.gz
[DEBUG]:   -> running rm -f .mark-qt-everywhere-opensource-src-5.7.0.tar.gz
[INFO]:    Downloading qt5 from http://download.qt.io/official_releases/qt/5.7/5.7.0/single/qt-everywhere-opensource-src-5.7.0.tar.gz
[DEBUG]:   -> running touch .mark-qt-everywhere-opensource-src-5.7.0.tar.gz
Traceback (most recent call last):
  File "/usr/lib/python2.7/runpy.py", line 174, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/media/hdd/home/thopiekar/Projekte/GIT/thopiekar/python-for-android_fork/pythonforandroid/toolchain.py", line 837, in <module>
    main()
  File "/media/hdd/home/thopiekar/Projekte/GIT/thopiekar/python-for-android_fork/pythonforandroid/toolchain.py", line 834, in main
    ToolchainCL()
  File "/media/hdd/home/thopiekar/Projekte/GIT/thopiekar/python-for-android_fork/pythonforandroid/toolchain.py", line 489, in __init__
    getattr(self, args.subparser_name.replace('-', '_'))(args)
  File "/media/hdd/home/thopiekar/Projekte/GIT/thopiekar/python-for-android_fork/pythonforandroid/toolchain.py", line 147, in wrapper_func
    build_dist_from_args(ctx, dist, args)
  File "/media/hdd/home/thopiekar/Projekte/GIT/thopiekar/python-for-android_fork/pythonforandroid/toolchain.py", line 190, in build_dist_from_args
    build_recipes(build_order, python_modules, ctx)
  File "pythonforandroid/build.py", line 540, in build_recipes
  File "pythonforandroid/recipe.py", line 342, in download_if_necessary
  File "pythonforandroid/recipe.py", line 385, in download
UnboundLocalError: local variable 'current_md5' referenced before assignment
'''

Author: thopiekar

pythonforandroid/recipe.py

@@ -381,11 +381,12 @@ def download(self):
                 self.download_file(url, filename)
                 shprint(sh.touch, marker_filename)
 
-                if self.md5sum is not None:
-                    print('downloaded md5: {}'.format(current_md5))
-                    print('expected md5: {}'.format(self.md5sum))
-                    print('md5 not handled yet, exiting')
-                    exit(1)
+                if exists(filename) and isfile(filename) and self.md5sum:
+                    if self.md5sum is not None:
+                        print('downloaded md5: {}'.format(current_md5))
+                        print('expected md5: {}'.format(self.md5sum))
+                        print('md5 not handled yet, exiting')
+                        exit(1)
 
     def unpack(self, arch):
         info_main('Unpacking {} for {}'.format(self.name, arch))