Issue #13930: Adds ability for 2to3 to write its output to a different
directory tree instead of overwriting the input files. Adds three command
line options: -o/--output-dir, -W/--write-unchanged-files and --add-suffix.
Feature backports into stable release branches for 2to3 are allowed by
a special exemption:
http://mail.python.org/pipermail/python-dev/2011-December/115089.html
diff --git a/Lib/lib2to3/main.py b/Lib/lib2to3/main.py
index 20ee434..ddcf002 100644
--- a/Lib/lib2to3/main.py
+++ b/Lib/lib2to3/main.py
@@ -25,12 +25,41 @@
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):
+ 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):
@@ -38,6 +67,23 @@
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):
+ os.makedirs(output_dir)
+ self.log_message('Writing converted %s to %s.', orig_filename,
+ filename)
if not self.nobackups:
# Make backup
backup = filename + ".bak"
@@ -55,6 +101,9 @@
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:
@@ -113,11 +162,33 @@
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:
@@ -143,6 +214,7 @@
# 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))
@@ -159,8 +231,23 @@
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)
+ 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: