"""
Main program for 2to3.
"""
from __future__ import with_statement, print_function
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):
"""
A refactoring tool that can avoid overwriting its input files.
Prints output to stdout.
Output files can optionally be written to a different directory and or
have an extra file suffix appended to their name for use in situations
where you do not want to replace the input files.
"""
def __init__(self, fixers, options, explicit, nobackups, show_diffs,
input_base_dir='', output_dir='', append_suffix=''):
"""
Args:
fixers: A list of fixers to import.
options: A dict with RefactoringTool configuration.
explicit: A list of fixers to run even if they are explicit.
nobackups: If true no backup '.bak' files will be created for those
files that are being refactored.
show_diffs: Should diffs of the refactoring be printed to stdout?
input_base_dir: The base directory for all input files. This class
will strip this path prefix off of filenames before substituting
it with output_dir. Only meaningful if output_dir is supplied.
All files processed by refactor() must start with this path.
output_dir: If supplied, all converted files will be written into
this directory tree instead of input_base_dir.
append_suffix: If supplied, all files output by this tool will have
this appended to their filename. Useful for changing .py to
.py3 for example by passing append_suffix='3'.
"""
self.nobackups = nobackups
self.show_diffs = show_diffs
if input_base_dir and not input_base_dir.endswith(os.sep):
input_base_dir += os.sep
self._input_base_dir = input_base_dir
self._output_dir = output_dir
self._append_suffix = append_suffix
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):
orig_filename = filename
if self._output_dir:
if filename.startswith(self._input_base_dir):
filename = os.path.join(self._output_dir,
filename[len(self._input_base_dir):])
else:
raise ValueError('filename %s does not start with the '
'input_base_dir %s' % (
filename, self._input_base_dir))
if self._append_suffix:
filename += self._append_suffix
if orig_filename != filename:
output_dir = os.path.dirname(filename)
if not os.path.isdir(output_dir) and output_dir:
os.makedirs(output_dir)
self.log_message('Writing converted %s to %s.', orig_filename,
filename)
if not self.nobackups:
# Make backup
backup = filename + ".bak"
if os.path.lexists(backup):
try:
os.remove(backup)
except OSError as err:
self.log_message("Can't remove backup %s", backup)
try:
os.rename(filename, backup)
except OSError as 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)
if orig_filename != filename:
# Preserve the file mode in the new output directory.
shutil.copymode(orig_filename, 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:
if self.output_lock is not None:
with self.output_lock:
for line in diff_lines:
print(line)
sys.stdout.flush()
else:
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("WARNING: %s" % (msg,), file=sys.stderr)
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 transformation from being run")
parser.add_option("-l", "--list-fixes", action="store_true",
help="List available transformations")
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")
parser.add_option("-o", "--output-dir", action="store", type="str",
default="", help="Put output files in this directory "
"instead of overwriting the input files. Requires -n.")
parser.add_option("-W", "--write-unchanged-files", action="store_true",
help="Also write files even if no changes were required"
" (useful with --output-dir); implies -w.")
parser.add_option("--add-suffix", action="store", type="str", default="",
help="Append this string to all output filenames."
" Requires -n if non-empty. "
"ex: --add-suffix='3' will generate .py3 files.")
# Parse command line arguments
refactor_stdin = False
flags = {}
options, args = parser.parse_args(args)
if options.write_unchanged_files:
flags["write_unchanged_files"] = True
if not options.write:
warn("--write-unchanged-files/-W implies -w.")
options.write = True
# If we allowed these, the original files would be renamed to backup names
# but not replaced.
if options.output_dir and not options.nobackups:
parser.error("Can't use --output-dir/-o without -n.")
if options.add_suffix and not options.nobackups:
parser.error("Can't use --add-suffix without -n.")
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("At least one file or directory argument required.", file=sys.stderr)
print("Use --help to show usage.", file=sys.stderr)
return 2
if "-" in args:
refactor_stdin = True
if options.write:
print("Can't write to stdin.", file=sys.stderr)
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)
logger = logging.getLogger('lib2to3.main')
# 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)
input_base_dir = os.path.commonprefix(args)
if (input_base_dir and not input_base_dir.endswith(os.sep)
and not os.path.isdir(input_base_dir)):
# One or more similar names were passed, their directory is the base.
# os.path.commonprefix() is ignorant of path elements, this corrects
# for that weird API.
input_base_dir = os.path.dirname(input_base_dir)
if options.output_dir:
input_base_dir = input_base_dir.rstrip(os.sep)
logger.info('Output in %r will mirror the input directory %r layout.',
options.output_dir, input_base_dir)
rt = StdoutRefactoringTool(
sorted(fixer_names), flags, sorted(explicit),
options.nobackups, not options.no_diffs,
input_base_dir=input_base_dir,
output_dir=options.output_dir,
append_suffix=options.add_suffix)
# 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("Sorry, -j isn't supported on this platform.",
file=sys.stderr)
return 1
rt.summarize()
# Return error status (0 if rt.errors is zero)
return int(bool(rt.errors))