Lib/lib2to3/main.py

   1 """
   2 Main program for 2to3.
   3 """
   4
   5 import sys
   6 import os
   7 import logging
   8 import shutil
   9 import optparse
  10
  11 from . import refactor
  12
  13
  14 class StdoutRefactoringTool(refactor.RefactoringTool):
  15     """
  16     Prints output to stdout.
  17     """
  18
  19     def __init__(self, fixers, options, explicit, nobackups):
  20         self.nobackups = nobackups
  21         super(StdoutRefactoringTool, self).__init__(fixers, options, explicit)
  22
  23     def log_error(self, msg, *args, **kwargs):
  24         self.errors.append((msg, args, kwargs))
  25         self.logger.error(msg, *args, **kwargs)
  26
  27     def write_file(self, new_text, filename, old_text):
  28         if not self.nobackups:
  29             # Make backup
  30             backup = filename + ".bak"
  31             if os.path.lexists(backup):
  32                 try:
  33                     os.remove(backup)
  34                 except os.error, err:
  35                     self.log_message("Can't remove backup %s", backup)
  36             try:
  37                 os.rename(filename, backup)
  38             except os.error, err:
  39                 self.log_message("Can't rename %s to %s", filename, backup)
  40         # Actually write the new file
  41         super(StdoutRefactoringTool, self).write_file(new_text,
  42                                                       filename, old_text)
  43         if not self.nobackups:
  44             shutil.copymode(backup, filename)
  45
  46     def print_output(self, lines):
  47         for line in lines:
  48             print line
  49
  50
  51 def main(fixer_pkg, args=None):
  52     """Main program.
  53
  54     Args:
  55         fixer_pkg: the name of a package where the fixers are located.
  56         args: optional; a list of command line arguments. If omitted,
  57               sys.argv[1:] is used.
  58
  59     Returns a suggested exit status (0, 1, 2).
  60     """
  61     # Set up option parser
  62     parser = optparse.OptionParser(usage="2to3 [options] file|dir ...")
  63     parser.add_option("-d", "--doctests_only", action="store_true",
  64                       help="Fix up doctests only")
  65     parser.add_option("-f", "--fix", action="append", default=[],
  66                       help="Each FIX specifies a transformation; default: all")
  67     parser.add_option("-x", "--nofix", action="append", default=[],
  68                       help="Prevent a fixer from being run.")
  69     parser.add_option("-l", "--list-fixes", action="store_true",
  70                       help="List available transformations (fixes/fix_*.py)")
  71     parser.add_option("-p", "--print-function", action="store_true",
  72                       help="Modify the grammar so that print() is a function")
  73     parser.add_option("-v", "--verbose", action="store_true",
  74                       help="More verbose logging")
  75     parser.add_option("-w", "--write", action="store_true",
  76                       help="Write back modified files")
  77     parser.add_option("-n", "--nobackups", action="store_true", default=False,
  78                       help="Don't write backups for modified files.")
  79
  80     # Parse command line arguments
  81     refactor_stdin = False
  82     options, args = parser.parse_args(args)
  83     if not options.write and options.nobackups:
  84         parser.error("Can't use -n without -w")
  85     if options.list_fixes:
  86         print "Available transformations for the -f/--fix option:"
  87         for fixname in refactor.get_all_fix_names(fixer_pkg):
  88             print fixname
  89         if not args:
  90             return 0
  91     if not args:
  92         print >>sys.stderr, "At least one file or directory argument required."
  93         print >>sys.stderr, "Use --help to show usage."
  94         return 2
  95     if "-" in args:
  96         refactor_stdin = True
  97         if options.write:
  98             print >>sys.stderr, "Can't write to stdin."
  99             return 2
 100
 101     # Set up logging handler
 102     level = logging.DEBUG if options.verbose else logging.INFO
 103     logging.basicConfig(format='%(name)s: %(message)s', level=level)
 104
 105     # Initialize the refactoring tool
 106     rt_opts = {"print_function" : options.print_function}
 107     avail_fixes = set(refactor.get_fixers_from_package(fixer_pkg))
 108     unwanted_fixes = set(fixer_pkg + ".fix_" + fix for fix in options.nofix)
 109     explicit = set()
 110     if options.fix:
 111         all_present = False
 112         for fix in options.fix:
 113             if fix == "all":
 114                 all_present = True
 115             else:
 116                 explicit.add(fixer_pkg + ".fix_" + fix)
 117         requested = avail_fixes.union(explicit) if all_present else explicit
 118     else:
 119         requested = avail_fixes.union(explicit)
 120     fixer_names = requested.difference(unwanted_fixes)
 121     rt = StdoutRefactoringTool(sorted(fixer_names), rt_opts, sorted(explicit),
 122                                options.nobackups)
 123
 124     # Refactor all files and directories passed as arguments
 125     if not rt.errors:
 126         if refactor_stdin:
 127             rt.refactor_stdin()
 128         else:
 129             rt.refactor(args, options.write, options.doctests_only)
 130         rt.summarize()
 131
 132     # Return error status (0 if rt.errors is zero)
 133     return int(bool(rt.errors))