main.py revision 608d8bcdfc1762cde31efdf02a6379a06d7964b1 
1"""
2Main program for 2to3.
3"""
4
5import sys
6import os
7import logging
8import shutil
9import optparse
10
11from . import refactor
12
13class StdoutRefactoringTool(refactor.MultiprocessRefactoringTool):
14    """
15    Prints output to stdout.
16    """
17
18    def __init__(self, fixers, options, explicit, nobackups):
19        self.nobackups = nobackups
20        super(StdoutRefactoringTool, self).__init__(fixers, options, explicit)
21
22    def log_error(self, msg, *args, **kwargs):
23        self.errors.append((msg, args, kwargs))
24        self.logger.error(msg, *args, **kwargs)
25
26    def write_file(self, new_text, filename, old_text):
27        if not self.nobackups:
28            # Make backup
29            backup = filename + ".bak"
30            if os.path.lexists(backup):
31                try:
32                    os.remove(backup)
33                except os.error as err:
34                    self.log_message("Can't remove backup %s", backup)
35            try:
36                os.rename(filename, backup)
37            except os.error as err:
38                self.log_message("Can't rename %s to %s", filename, backup)
39        # Actually write the new file
40        super(StdoutRefactoringTool, self).write_file(new_text,
41                                                      filename, old_text)
42        if not self.nobackups:
43            shutil.copymode(backup, filename)
44
45    def print_output(self, lines):
46        for line in lines:
47            print(line)
48
49
50def main(fixer_pkg, args=None):
51    """Main program.
52
53    Args:
54        fixer_pkg: the name of a package where the fixers are located.
55        args: optional; a list of command line arguments. If omitted,
56              sys.argv[1:] is used.
57
58    Returns a suggested exit status (0, 1, 2).
59    """
60    # Set up option parser
61    parser = optparse.OptionParser(usage="2to3 [options] file|dir ...")
62    parser.add_option("-d", "--doctests_only", action="store_true",
63                      help="Fix up doctests only")
64    parser.add_option("-f", "--fix", action="append", default=[],
65                      help="Each FIX specifies a transformation; default: all")
66    parser.add_option("-j", "--processes", action="store", default=1,
67                      type="int", help="Run 2to3 concurrently")
68    parser.add_option("-x", "--nofix", action="append", default=[],
69                      help="Prevent a fixer from being run.")
70    parser.add_option("-l", "--list-fixes", action="store_true",
71                      help="List available transformations (fixes/fix_*.py)")
72    parser.add_option("-p", "--print-function", action="store_true",
73                      help="Modify the grammar so that print() is a function")
74    parser.add_option("-v", "--verbose", action="store_true",
75                      help="More verbose logging")
76    parser.add_option("-w", "--write", action="store_true",
77                      help="Write back modified files")
78    parser.add_option("-n", "--nobackups", action="store_true", default=False,
79                      help="Don't write backups for modified files.")
80
81    # Parse command line arguments
82    refactor_stdin = False
83    options, args = parser.parse_args(args)
84    if not options.write and options.nobackups:
85        parser.error("Can't use -n without -w")
86    if options.list_fixes:
87        print("Available transformations for the -f/--fix option:")
88        for fixname in refactor.get_all_fix_names(fixer_pkg):
89            print(fixname)
90        if not args:
91            return 0
92    if not args:
93        print("At least one file or directory argument required.", file=sys.stderr)
94        print("Use --help to show usage.", file=sys.stderr)
95        return 2
96    if "-" in args:
97        refactor_stdin = True
98        if options.write:
99            print("Can't write to stdin.", file=sys.stderr)
100            return 2
101
102    # Set up logging handler
103    level = logging.DEBUG if options.verbose else logging.INFO
104    logging.basicConfig(format='%(name)s: %(message)s', level=level)
105
106    # Initialize the refactoring tool
107    rt_opts = {"print_function" : options.print_function}
108    avail_fixes = set(refactor.get_fixers_from_package(fixer_pkg))
109    unwanted_fixes = set(fixer_pkg + ".fix_" + fix for fix in options.nofix)
110    explicit = set()
111    if options.fix:
112        all_present = False
113        for fix in options.fix:
114            if fix == "all":
115                all_present = True
116            else:
117                explicit.add(fixer_pkg + ".fix_" + fix)
118        requested = avail_fixes.union(explicit) if all_present else explicit
119    else:
120        requested = avail_fixes.union(explicit)
121    fixer_names = requested.difference(unwanted_fixes)
122    rt = StdoutRefactoringTool(sorted(fixer_names), rt_opts, sorted(explicit),
123                               options.nobackups)
124
125    # Refactor all files and directories passed as arguments
126    if not rt.errors:
127        if refactor_stdin:
128            rt.refactor_stdin()
129        else:
130            try:
131                rt.refactor(args, options.write, options.doctests_only,
132                            options.processes)
133            except refactor.MultiprocessingUnsupported:
134                assert options.processes > 1
135                print >> sys.stderr, "Sorry, -j isn't " \
136                    "supported on this platform."
137                return 1
138        rt.summarize()
139
140    # Return error status (0 if rt.errors is zero)
141    return int(bool(rt.errors))
142