cpython/Lib/lib2to3/main.py

175 lines
6.4 KiB
Python

"""
Main program for 2to3.
"""
import sys
import os
import difflib
import logging
import shutil
import optparse
from . import refactor
def diff_texts(a, b, filename):
"""Return a unified diff of two strings."""
a = a.splitlines()
b = b.splitlines()
return difflib.unified_diff(a, b, filename, filename,
"(original)", "(refactored)",
lineterm="")
class StdoutRefactoringTool(refactor.MultiprocessRefactoringTool):
"""
Prints output to stdout.
"""
def __init__(self, fixers, options, explicit, nobackups, show_diffs):
self.nobackups = nobackups
self.show_diffs = show_diffs
super(StdoutRefactoringTool, self).__init__(fixers, options, explicit)
def log_error(self, msg, *args, **kwargs):
self.errors.append((msg, args, kwargs))
self.logger.error(msg, *args, **kwargs)
def write_file(self, new_text, filename, old_text, encoding):
if not self.nobackups:
# Make backup
backup = filename + ".bak"
if os.path.lexists(backup):
try:
os.remove(backup)
except os.error, err:
self.log_message("Can't remove backup %s", backup)
try:
os.rename(filename, backup)
except os.error, err:
self.log_message("Can't rename %s to %s", filename, backup)
# Actually write the new file
write = super(StdoutRefactoringTool, self).write_file
write(new_text, filename, old_text, encoding)
if not self.nobackups:
shutil.copymode(backup, filename)
def print_output(self, old, new, filename, equal):
if equal:
self.log_message("No changes to %s", filename)
else:
self.log_message("Refactored %s", filename)
if self.show_diffs:
diff_lines = diff_texts(old, new, filename)
try:
for line in diff_lines:
print line
except UnicodeEncodeError:
warn("couldn't encode %s's diff for your terminal" %
(filename,))
return
def warn(msg):
print >> sys.stderr, "WARNING: %s" % (msg,)
def main(fixer_pkg, args=None):
"""Main program.
Args:
fixer_pkg: the name of a package where the fixers are located.
args: optional; a list of command line arguments. If omitted,
sys.argv[1:] is used.
Returns a suggested exit status (0, 1, 2).
"""
# Set up option parser
parser = optparse.OptionParser(usage="2to3 [options] file|dir ...")
parser.add_option("-d", "--doctests_only", action="store_true",
help="Fix up doctests only")
parser.add_option("-f", "--fix", action="append", default=[],
help="Each FIX specifies a transformation; default: all")
parser.add_option("-j", "--processes", action="store", default=1,
type="int", help="Run 2to3 concurrently")
parser.add_option("-x", "--nofix", action="append", default=[],
help="Prevent a fixer from being run.")
parser.add_option("-l", "--list-fixes", action="store_true",
help="List available transformations (fixes/fix_*.py)")
parser.add_option("-p", "--print-function", action="store_true",
help="Modify the grammar so that print() is a function")
parser.add_option("-v", "--verbose", action="store_true",
help="More verbose logging")
parser.add_option("--no-diffs", action="store_true",
help="Don't show diffs of the refactoring")
parser.add_option("-w", "--write", action="store_true",
help="Write back modified files")
parser.add_option("-n", "--nobackups", action="store_true", default=False,
help="Don't write backups for modified files.")
# Parse command line arguments
refactor_stdin = False
flags = {}
options, args = parser.parse_args(args)
if not options.write and options.no_diffs:
warn("not writing files and not printing diffs; that's not very useful")
if not options.write and options.nobackups:
parser.error("Can't use -n without -w")
if options.list_fixes:
print "Available transformations for the -f/--fix option:"
for fixname in refactor.get_all_fix_names(fixer_pkg):
print fixname
if not args:
return 0
if not args:
print >> sys.stderr, "At least one file or directory argument required."
print >> sys.stderr, "Use --help to show usage."
return 2
if "-" in args:
refactor_stdin = True
if options.write:
print >> sys.stderr, "Can't write to stdin."
return 2
if options.print_function:
flags["print_function"] = True
# Set up logging handler
level = logging.DEBUG if options.verbose else logging.INFO
logging.basicConfig(format='%(name)s: %(message)s', level=level)
# Initialize the refactoring tool
avail_fixes = set(refactor.get_fixers_from_package(fixer_pkg))
unwanted_fixes = set(fixer_pkg + ".fix_" + fix for fix in options.nofix)
explicit = set()
if options.fix:
all_present = False
for fix in options.fix:
if fix == "all":
all_present = True
else:
explicit.add(fixer_pkg + ".fix_" + fix)
requested = avail_fixes.union(explicit) if all_present else explicit
else:
requested = avail_fixes.union(explicit)
fixer_names = requested.difference(unwanted_fixes)
rt = StdoutRefactoringTool(sorted(fixer_names), flags, sorted(explicit),
options.nobackups, not options.no_diffs)
# Refactor all files and directories passed as arguments
if not rt.errors:
if refactor_stdin:
rt.refactor_stdin()
else:
try:
rt.refactor(args, options.write, options.doctests_only,
options.processes)
except refactor.MultiprocessingUnsupported:
assert options.processes > 1
print >> sys.stderr, "Sorry, -j isn't " \
"supported on this platform."
return 1
rt.summarize()
# Return error status (0 if rt.errors is zero)
return int(bool(rt.errors))