tobiko/tobiko/shell/sh/_command.py

85 lines
2.3 KiB
Python

# Copyright (c) 2019 Red Hat, Inc.
#
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
from __future__ import absolute_import
import shlex
import typing # noqa
class ShellCommand(tuple):
def __repr__(self):
return "ShellCommand([{!s}])".format(', '.join(self))
def __str__(self):
return list_to_command_line(self)
def __add__(self, other):
other = shell_command(other)
return shell_command(tuple(self) + other)
ShellCommandType = typing.Union[ShellCommand, str, typing.Iterable]
def shell_command(command: ShellCommandType) -> ShellCommand:
if isinstance(command, ShellCommand):
return command
elif isinstance(command, str):
return ShellCommand(shlex.split(command))
else:
return ShellCommand(str(a) for a in command)
def list_to_command_line(seq):
result = []
for arg in seq:
bs_buf = []
# Add a space to separate this argument from the others
if result:
result.append(' ')
needquote = (" " in arg) or ("\t" in arg) or not arg
if needquote:
result.append("'")
for c in arg:
if c == '\\':
# Don't know if we need to double yet.
bs_buf.append(c)
elif c == '"':
# Double backslashes.
result.append('\\' * len(bs_buf)*2)
bs_buf = []
result.append('\\"')
else:
# Normal char
if bs_buf:
result.extend(bs_buf)
bs_buf = []
result.append(c)
# Add remaining backslashes, if any.
if bs_buf:
result.extend(bs_buf)
if needquote:
result.extend(bs_buf)
result.append("'")
return ''.join(result)