1 #!/usr/bin/env python

     1 #!/usr/bin/env python

     2 

     2 

     4 

     4 

     5 import ast

     5 import ast

     6 import collections

     6 import collections

     7 import os

     7 import os

     8 import sys

     8 import sys

   542 def find_cycles(imports):

   542 def find_cycles(imports):

   543     """Find cycles in an already-loaded import graph.

   543     """Find cycles in an already-loaded import graph.

   544 

   544 

   545     All module names recorded in `imports` should be absolute one.

   545     All module names recorded in `imports` should be absolute one.

   546 

   546 

   547     >>> imports = {'top.foo': ['top.bar', 'os.path', 'top.qux'],

   548     >>> imports = {'top.foo': ['top.bar', 'os.path', 'top.qux'],

   548     ...            'top.bar': ['top.baz', 'sys'],

   549     ...            'top.bar': ['top.baz', 'sys'],

   549     ...            'top.baz': ['top.foo'],

   550     ...            'top.baz': ['top.foo'],

   550     ...            'top.qux': ['top.foo']}

   551     ...            'top.qux': ['top.foo']}

   552     top.bar -> top.baz -> top.foo -> top.bar

   553     top.bar -> top.baz -> top.foo -> top.bar

   553     top.foo -> top.qux -> top.foo

   554     top.foo -> top.qux -> top.foo

   554     """

   555     """

   555     cycles = set()

   556     cycles = set()

   556     for mod in sorted(imports.iterkeys()):

   557     for mod in sorted(imports.iterkeys()):

   564 def _cycle_sortkey(c):

   565 def _cycle_sortkey(c):

   565     return len(c), c

   566     return len(c), c

   566 

   567 

   567 def main(argv):

   568 def main(argv):

   568     if len(argv) < 2 or (argv[1] == '-' and len(argv) > 2):

   569     if len(argv) < 2 or (argv[1] == '-' and len(argv) > 2):

   570         return 1

   571         return 1

   571     if argv[1] == '-':

   572     if argv[1] == '-':

   572         argv = argv[:1]

   573         argv = argv[:1]

   573         argv.extend(l.rstrip() for l in sys.stdin.readlines())

   574         argv.extend(l.rstrip() for l in sys.stdin.readlines())

   574     localmods = {}

   575     localmods = {}

   582         src = f.read()

   583         src = f.read()

   583         used_imports[modname] = sorted(

   584         used_imports[modname] = sorted(

   584             imported_modules(src, modname, localmods, ignore_nested=True))

   585             imported_modules(src, modname, localmods, ignore_nested=True))

   585         for error, lineno in verify_import_convention(modname, src, localmods):

   586         for error, lineno in verify_import_convention(modname, src, localmods):

   586             any_errors = True

   587             any_errors = True

   588         f.close()

   589         f.close()

   589     cycles = find_cycles(used_imports)

   590     cycles = find_cycles(used_imports)

   590     if cycles:

   591     if cycles:

   591         firstmods = set()

   592         firstmods = set()

   592         for c in sorted(cycles, key=_cycle_sortkey):

   593         for c in sorted(cycles, key=_cycle_sortkey):

   594             # As a rough cut, ignore any cycle that starts with the

   595             # As a rough cut, ignore any cycle that starts with the

   595             # same module as some other cycle. Otherwise we see lots

   596             # same module as some other cycle. Otherwise we see lots

   596             # of cycles that are effectively duplicates.

   597             # of cycles that are effectively duplicates.

   597             if first in firstmods:

   598             if first in firstmods:

   598                 continue

   599                 continue

   600             firstmods.add(first)

   601             firstmods.add(first)

   601         any_errors = True

   602         any_errors = True

   602     return any_errors != 0

   603     return any_errors != 0

   603 

   604 

   604 if __name__ == '__main__':

   605 if __name__ == '__main__':