Zsh prompt with directory and virtual environment - terminal

Question

I am having trouble finding a succinct answer to this. I am using Oh My Zsh, and right now using the default theme, robbyrussell.
I would like my prompt to have 2 components:
The current directory, plus one level up
If I am using a virtual environment (like anaconda), have the name of the active environment in parentheses.

Answer 1

Below is the way to do it, you can customize it as per your needs
# Helper method to add background and foreground colors
prompt_segment () {
local bg fg
[[ -n $1 ]] && bg="%K{$1}" || bg="%k"
[[ -n $2 ]] && fg="%F{$2}" || fg="%f"
if [[ $CURRENT_BG != 'NONE' && $1 != $CURRENT_BG ]]
then
echo -n " %{$bg%F{$CURRENT_BG}%}$SEGMENT_SEPARATOR%{$fg%} "
else
echo -n "%{$bg%}%{$fg%} "
fi
CURRENT_BG=$1
[[ -n $3 ]] && echo -n $3
}
prompt_virtualenv () {
# Check if we are in a virtual environment
# if we are then VIRTUAL_ENV variable will be set
local virtualenv_path="$VIRTUAL_ENV"
if [[ -n $virtualenv_path && -n $VIRTUAL_ENV_DISABLE_PROMPT ]]
then
# We are in virtual env so show just the project name
prompt_segment blue black "(`basename $virtualenv_path`)"
fi
}
prompt_directory() {
# Show the current directory
prompt_segment red blue $PWD
}
build_my_zsh_prompt() {
# Call all the prompt functions to build the actual prompt
prompt_virtualenv
prompt_directory
prompt_segment black white ""
}
# Assign the PROMPT variable with the function, so bash call it everytime
# Single quotes are important here, else you will get a fixed PROMPT
# Without single quotes, the function will be called once and evaluated value
# will be assigned
PROMPT='$(build_my_zsh_prompt)'
PROMPT variable is used by zsh shell to determine what needs to be displayed as the prompt. When we set PROMPT=$(build_my_zsh_prompt), we are asking shell to call our function build_my_zsh_prompt.
This function in turn (ideally) should call different function which create individual parts of prompt. Now let's look at prompt_directory
prompt_segment black red $PWD"
The prompt_segment is a helper function to echo some text with background and the foreground color
First parameter black is the background and second parameter red is the foreground color in this case. Next we show what text needs to be given for this prompt.
All of this needs to be added to your ~/.zshrc file at the very end