[Aptana Studio 3: Convert print to print()] Aptana Studio 3 ruble commands which convert between Python 2 and Python 3 print statement syntax using lib2to3 and lib3to2. #aptanastudio #ruble #command #conversion #syntax #userscript #python #python3

convert_print.py

#!/usr/local/bin/python
# -*- coding: utf-8 -*-
# 
#  convert_print.py
#  Aptana Ruble Commands
#  
#  Created by André Berg on 28.05.2013.
#  Copyright 2013 Berg Media. All rights reserved.
#  
#  Used from a Python.ruble command in Eclipse 
#  Aptana Studio 3:
#  
#   require 'ruble'
# 
#   command t(:convert_print_2to3) do |cmd|
#     cmd.output = :replace_selection
#     cmd.input = :selection
#     cmd.invoke do |context|
#       text = "#{STDIN.read.gsub('\\', '\\\\').gsub('"', '\\"')}"
#       return `"${TM_PYTHON:-python}" "${TM_BUNDLE_SUPPORT}/convert_print.py" "-3" "#{text}"`.rstrip
#     end
#   end

from __future__ import print_function

import io
import os
import sys
import tempfile
from contextlib import contextmanager
from lib2to3.main import main as to3_main

try:
    from lib3to2.main import main as to2_main
    IS_LIB3TO2_SUPPORTED = True
except ImportError:
    err_msg = ("W: lib3to2 not found. -2 direction not supported. " 
               "(install '3to2' or '3to2_py3k' via pip or easy_install)")
    print(err_msg, file=sys.stderr)
    IS_LIB3TO2_SUPPORTED = False

if sys.version_info < (3, 0):
    IS_PYTHON3 = False
else:
    IS_PYTHON3 = True


class DummyFile(object):
    def write(self, x):
        pass


@contextmanager
def muted_stderr():
    saved_stderr = sys.stderr
    sys.stderr = DummyFile()
    yield
    sys.stderr = saved_stderr
    

def convert_print(text, target=3, encoding=sys.getdefaultencoding()):
    if not IS_PYTHON3:
        try:
            text = unicode(text.encode(encoding))
        except UnicodeDecodeError as ude:
            # FIXME: on Windows, Pydev passes Run Config args as "cp1252" encoded.
            # Frankly, I have no idea why Pydev is passing these arguments 
            # with the platform default encoding and not the encoding set in 
            # either Eclipse prefs, project prefs, file prefs, file header 
            # comment or even from sitecustomize.py or pydev_sitecustomize.py.
            # I am assuming it has to do with Jython being used to determine 
            # the PYTHONPATH for the execution.
            if sys.platform.startswith("win"):
                text = unicode(text.decode("cp1252").encode(encoding))
            else:
                raise ude
    if target == 3:
        _main = to3_main
        module_name = "lib2to3.fixes"
    elif target == 2:
        _main = to2_main
        module_name = "lib3to2.fixes"
    else:
        raise ValueError("E: target must be one of [2, 3], but is {0!r}".format(target))
    tmpfile_name = "convert_print_py_scratchfile.txt"
    tmpdir = tempfile.gettempdir()
    tmpfile_path = os.path.join(tmpdir, tmpfile_name)
    with io.open(tmpfile_path, "wt", encoding=encoding) as temp_file:
        temp_file.write(text)
    err = None
    with muted_stderr():
        try:
            _main(module_name, args=["--nobackups", "--write", "--no-diffs", "--fix=print", tmpfile_path])
        except Exception as e:  # IGNORE:W0703
            err = e
    if err is None:
        with io.open(tmpfile_path, "rt", encoding=encoding) as fixed_file:
            result = fixed_file.read()
    else:
        raise err  # IGNORE:E0702
    return result


if __name__ == '__main__':
    program_name = os.path.basename(sys.argv[0])
    if IS_LIB3TO2_SUPPORTED:
        flag_str = "[-2|-3]"
    else:
        flag_str = "[-3]"
    if not len(sys.argv) > 2:
        print("usage: {0} {1} '<text>'".format(program_name, flag_str))
        sys.exit(1)
    direction = sys.argv[1]
    if direction == "-2":
        if not IS_LIB3TO2_SUPPORTED:
            err_str = ("E: -2 direction not supported, because lib3to2 is missing. "
                       "(install '3to2' or '3to2_py3k' via pip or easy_install)")
            print(err_str)
            sys.exit(1)
        target = 2
    elif direction == "-3":
        target = 3
    else:
        print("E: direction must be one of ['-2', '-3'], but is {0!r}".format(direction), file=sys.stderr)
        sys.exit(1)
    text = sys.argv[2]
    fixed_text = convert_print(text, target=target)
    if len(fixed_text) < 1:
        fixed_text = text
    print(fixed_text)

convert_print_2to3.rb

# encoding: utf-8
require 'ruble'
# XXX should probably use Shellwords.shellescape

command t(:convert_print_2to3) do |cmd|
  #cmd.scope = 'source.py'
  cmd.output = :replace_selection
  cmd.input = :selection
  cmd.invoke do |context|
    text = "#{STDIN.read.gsub('\\', '\\\\').gsub('"', '\\"')}"
    return `"${TM_PYTHON:-python}" "${TM_BUNDLE_SUPPORT}/convert_print.py" "-3" "#{text}"`.rstrip
  end
end

convert_print_3to2.rb

# encoding: utf-8
require 'ruble'

command t(:convert_print_3to2) do |cmd|
  #cmd.scope = 'source.py'
  cmd.output = :replace_selection
  cmd.input = :selection
  cmd.invoke do |context|
    text = "#{STDIN.read.gsub('\\', '\\\\').gsub('"', '\\"')}"
    return `"${TM_PYTHON:-python}" "${TM_BUNDLE_SUPPORT}/convert_print.py" "-2" "#{text}"`.rstrip
  end
end