DIRECTLY run(i.e., python xxx/xxx/input_test.py) the file below and input other Chinese characters, then press backspace to delete them. You will find that you cannot delete them all, and even the cursor in the terminal misplaces and overlaps with the characters.

This issue is only reproduced under Mac OS X, everything is fine with Windows.

input() uses readline. On macOS, readline is provided by libedit. It may be a bug in libedit which is an external dependency, and so not maintained by Python.

I could reproduce the behavior that console output doesn't match what Python gets. I agree with Victor this may not be a Python problem. I could also reproduce the behavior with Ruby reading Chinese characters from console.

FTR:
> On macOS, readline is provided by libedit.

It *may* be provided by libedit. GNU readline is also commonly used on macOS, although it is not provided by Apple.  The easiest way to tell which is in use is to examine the __doc__ attribute of the readline module:

$ /usr/local/bin/python3.6 -c 'import readline;print(readline.__doc__)'
Importing this module enables command line editing using libedit readline.
$ /macports/bin/python3.6 -c 'import readline;print(readline.__doc__)'
Importing this module enables command line editing using GNU readline.

https://docs.python.org/3/library/readline.html#module-readline

Xiang Zhang, was that on macOS?  If so, can someone try on one or more Linux systems with a Chinese locale?  I see the same behavior on Linux but I'm not sure that I'm testing it properly.

Yes, it's on MacOS. libedit and GNU deadline both have the behavior.  I can see the same behavior on Ubuntu, LANG=en_US.UTF-8.

So it's not a macOS-specific issue: editing the title et al accordingly

New changeset f7a19c28bda7b0ed3a440db80202013a86af6850 by Victor Stinner in branch '3.6':
bpo-33692: pythoninfo detect libedit on Python 3.6 (GH-7244)
https://github.com/python/cpython/commit/f7a19c28bda7b0ed3a440db80202013a86af6850

New changeset 9994eff17f943fb2c190708b12c96fef9838a425 by Victor Stinner in branch '2.7':
bpo-33692: pythoninfo detect libedit on Python 2.7 (#7246)
https://github.com/python/cpython/commit/9994eff17f943fb2c190708b12c96fef9838a425

Hello everyone, do we have a walkaround for this issue now? I barely read your discussion.

Hey there! I saw your pull requests to python3.6 and have been merged, so what should we do now? Just update the python to higher a version?

> Hey there! I saw your pull requests to python3.6 and have been merged, so what should we do now? Just update the python to higher a version?

Oh. My changes are just to add debug traces in the "python3 -m test.pythoninfo" command which is used on buildbots, Travis CI and AppVeyor to ease debug when a test fails.

It's not a fix.

New changeset ef634b5b26f14d942768069fa23f9791a06ff37e by Victor Stinner in branch 'master':
bpo-33692: pythoninfo detect libedit on Python 3.6 (GH-7293)
https://github.com/python/cpython/commit/ef634b5b26f14d942768069fa23f9791a06ff37e

New changeset b9afe645c4926b1f086f30ba9bd00671b0b8b55e by Victor Stinner in branch '3.6':
bpo-33692: Update pythoninfo from master (GH-7301)
https://github.com/python/cpython/commit/b9afe645c4926b1f086f30ba9bd00671b0b8b55e

New changeset 466aae545786d2db5ac27f243c5d77aeb7a5958e by Victor Stinner in branch '3.7':
bpo-33692: Update pythoninfo from master (GH-7298)
https://github.com/python/cpython/commit/466aae545786d2db5ac27f243c5d77aeb7a5958e

New changeset 0f642620a8a85ef0b5482f253205baf1865e05b2 by Victor Stinner in branch '2.7':
bpo-33692: Update pythoninfo from master (GH-7304)
https://github.com/python/cpython/commit/0f642620a8a85ef0b5482f253205baf1865e05b2