Description
- Poetry version: 1.4.2
- Python version: 3.11.2
- OS version and name: Ubuntu 23.04
- I am on the latest stable Poetry version, installed using a recommended method.
- I have searched the issues of this repo and believe that this is not a duplicate.
- I have consulted the FAQ and blog for any relevant entries or release notes.
- If an exception occurs when executing a command, I executed it again in debug mode (
-vvv
option) and have included the output below.
Issue
Related: #18 python-poetry/poetry#571
This is a result of me diagnosing why poetry shell
starts a new shell, but without the virtual env activated.
Looking at how poetry uses the shell, it uses pexpect to run it, writing the command to activate the python environment as its first input. This breaks in all configurations that read anything before that; particularly, any configuration that uses VT100 escape sequences that read anything. These may be more or less common in, for example, prompts.
For example, I have this in my .bashrc, essentially from this StackOverflow comment:
new_line_ps1() {
local _ y x _
local LIGHT_YELLOW="\001\033[1;93m\002"
local RESET="\001\e[0m\002"
IFS='[;' read -p $'\e[6n' -d R -rs _ y x _
if [[ "$x" != 1 ]]; then
printf "\n${LIGHT_YELLOW}^^ no newline at end of output ^^\n${RESET}"
fi
}
if [ "$color_prompt" = yes ]; then
PS1='$(new_line_ps1)${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
else
PS1='$(new_line_ps1)${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
fi
unset color_prompt force_color_prompt
My analysis of what happens:
What this prompt does is it outputs the "\e[6n" VT100 escape code to read cursor position. VT100 compliant terminals respond to this by producing the a string like "\e[10;1R" as if input from a keyboard. This can then be read by the program to determine that the cursor is on line 10, column 1.
The way poetry shell
is implemented, it typically claims to be VT100 compliant if run from such a terminal (because it does not change the TERM environment variable), yet it does not respond to VT100 queries the shell outputs before giving it the activation command. In this case, that results in the read command in the prompt reading (part of) the activation command.