My poor English... I hope you can understand.
When the window is not wide enough, something strange happens.

Steps to Reproduce:
$mkdir 这是一个很长很长很长很长很长很长很长很长很长很长很长很长很长很长很长很长很长很长很长的目录名哦
$cd 这是一个很长很长很长很长很长很长很长很长很长很长很长很长很长很长很长很长很长很长很长的目录名哦

make the window narrow enough so that the directory name can't be shown in a single line.

Result:
Some character becomes '�'