💄 Jaka's prompt zsh theme (with abbreviated folder names in the prompt)

jakas-prompt.zsh-theme

# The original theme this theme is extended from
# is the gallifrey.zsh-theme from oh-my-zsh.

# To use this theme, make a new file called jakas-prompt.zsh-theme
# in the directory ~/.oh-my-zsh/themes, and change the THEME variabl
# in your ~/.zshrc to jakas-prompt.

return_code="%(?..%{$fg[red]%}%? ↵%{$reset_color%})"

function dirprompt {
  # Function for abbreviating folder names instead of listing
  # the pwd output.
  #
  # Turns /Users/jaka/some/folder into j/s/folder for a shorter
  # input in the terminal prompt.
  #
  # Takes in the current directory,
  # gets all of the strings ending with a / character,
  # e.g., from /Users/jaka/test it gets Users/ and jaka/.
  #
  # Then, it extracts the match group 1 from the matches,
  # where it matches only the first character in each match,
  # e.g., from /Users it gets U and from jaka/ it gets j.
  #
  # The match gets replaced in the output with the match group 1,
  # meaning that each folder name gets substituted with its initial
  # letter.
  #
  # Since the last folder is not matched by the regex, its
  # full name remains in the output of the prompt.
  #
  # To extract only the last few folders, each regex match
  # gets a newline character at the end of its substitution
  # so that the tail command can then be used.
  #
  # After using the tail command, we join the lines using tr
  # and remove the weird first new line using another tail.
  #
  # After that, we get rid of the weird output for the home directory,
  # and replace // in e.g. //jaka to /, to get e.g. /jaka in the home directory.
  pwd | sed -E 's/(.)([^\/]+)\//\1\/\n/g' | tail -3 | tr -d '\n' | tail | tr -s "//" "/"
}

PROMPT='$(dirprompt)~ $(git_prompt_info)%{$reset_color%}%B»%b '
RPS1="${return_code}"

ZSH_THEME_GIT_PROMPT_PREFIX="%{$fg[yellow]%}‹"
ZSH_THEME_GIT_PROMPT_SUFFIX="› %{$reset_color%}"

unset return_code host_color