Shell CLI Readability

#bash #linux #beginners #tutorial

This configuration helps make my command line interface a bit more readable and increases the ease of use. It prevents from needing some consistent chores:

Running pwd to see where you are
Running git status to see which branch you are in
Investigating when you ran that one command a while ago

Zsh

Context

My setup is currently running macOS Ventura, using iTerm2 with Zsh.

My command line appears as:

This is showing the current date and which directory I am in, as well as the git branch (if this is a git repository):

<DATE>@<TIME>[<WORKING_DIRECTORY>][<GIT_BRANCH>]:

Configuration

This customization can be done by editing an existing ~/.zshrc file or creating one. My current ~/.zshrc:

autoload -Uz vcs_info
precmd_vcs_info() { vcs_info }
precmd_functions+=( precmd_vcs_info )
setopt prompt_subst
zstyle ':vcs_info:git:*' formats '%b'

PROMPT='%F{#FE9A0A}%D%f%F{#09CAFF}@%f%T[%F{#0165F5}%~%f[%F{#78D236}${vcs_info_msg_0_}%f]: '

First section is for loading the version control system (git in this case) and displaying the branch.

Prompt Options

Within the prompt:

%F{}...%f
- This formatting indicates the text in the ... area will be of the color within the {}
%F{#FE9A0A}%D%f
- %D indicates a date format of YY-MM-DD
%F{#09CAFF}@%f
- This is only the character @
%T
- Indicates the 24 hour time in format HH:MM
[
- This is only the character [
%F{#0165F5}%~%f
][
- This is only the characters ][
%F{#78D236}${vcs_info_msg_0_}%f
- ${vcs_info_msg_0_} will display the current git branch
]:
- This is only the characters ]:

Bash

Context

My setup is currently running macOS Catalina, using iTerm2 with Bash.

My command line appears as:

This is showing the current date and which directory I am in, as well as the git branch (if this is a git repository):

06.12.2020@13:50[current-directory][git-branch-name]:

Configuration

This customization can be done by editing an existing ~/.bashrc or ~/.bash_profile file, or creating one. This file needs to export PS1, which is the primary prompt. My current ~/.bash_profile:

# get current branch in git repo
function parse_git_branch() {
    BRANCH=`git branch 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/\1/'`
    if [ ! "${BRANCH}" == "" ]
    then
        STAT=`parse_git_dirty`
        echo "[${BRANCH}${STAT}]"
    else
        echo ""
    fi
}

# get current status of git repo
function parse_git_dirty {
    status=`git status 2>&1 | tee`
    dirty=`echo -n "${status}" 2> /dev/null | grep "modified:" &> /dev/null; echo "$?"`
    untracked=`echo -n "${status}" 2> /dev/null | grep "Untracked files" &> /dev/null; echo "$?"`
    ahead=`echo -n "${status}" 2> /dev/null | grep "Your branch is ahead of" &> /dev/null; echo "$?"`
    newfile=`echo -n "${status}" 2> /dev/null | grep "new file:" &> /dev/null; echo "$?"`
    renamed=`echo -n "${status}" 2> /dev/null | grep "renamed:" &> /dev/null; echo "$?"`
    deleted=`echo -n "${status}" 2> /dev/null | grep "deleted:" &> /dev/null; echo "$?"`
    bits=''
    if [ "${renamed}" == "0" ]; then
        bits=">${bits}"
    fi
    if [ "${ahead}" == "0" ]; then
        bits="*${bits}"
    fi
    if [ "${newfile}" == "0" ]; then
        bits="+${bits}"
    fi
    if [ "${untracked}" == "0" ]; then
        bits="?${bits}"
    fi
    if [ "${deleted}" == "0" ]; then
        bits="x${bits}"
    fi
    if [ "${dirty}" == "0" ]; then
        bits="!${bits}"
    fi
    if [ ! "${bits}" == "" ]; then
        echo " ${bits}"
    else
        echo ""
    fi
}

export PS1="\[\e[38;5;214m\]\D{%d.%m.%Y}\[\e[36m\]@\[\e[m\]\A\[\e[m\][\[\e[38;5;63m\]\W\[\e[m\]]\[\e[38;5;82m\]\`parse_git_branch\`\[\e[m\]: "

This parse_git_dirty function will cause the ...[git-branch-name] section of my prompt to include the following optional characters:

*: This branch is ahead of main
+: A new file exists in this branch
?: Untracked files exist in this branch
x: Files have been deleted from this branch
!: Files have been modified in this branch

Prompt Options

\d: Date in “Weekday Month Date” format (e.g., Tue May 26)
\D{format}: Date in format passed in
\j: Number of jobs currently managed by the shell
\l: Basename of the shells terminal device
\n: Newline
\s: Name of the shell
\t: Current time in 24-hour HH:MM:SS format
\T: Current time in 12-hour HH:MM:SS format
\@: Current time in 12-hour am/pm format
\A: Current time in 24-hour HH:MM format
\u: Username of the current user
\w: Current working directory ($HOME is represented by ~)
\W: Basename of the working directory ($HOME is represented by ~)
\!: History number of this command
\#: Command number of this command
\$: Specifies whether the user is root (#) or otherwise ($)
\\: Backslash
\[: Start a sequence of non-displayed characters (useful if you want to add a command or instruction set to the prompt)
\]: Close or end a sequence of non-displayed characters

Note that my PS1 includes the following sections:

# Orange
\[\e[38;5;214m\]
# Date, in format
\D{%d.%m.%Y}
# Teal
\[\e[36m\]
# @ symbol
@
# Plain color
\[\e[m\]
# Time, 24hr format
\A
# Plain color
\[\e[m\]
# Open bracket symbol
[
# Blue
\[\e[38;5;63m\]
# Current directory, not path
\W
# Plain color
\[\e[m\]
# Close bracket symbol
]
# Green
\[\e[38;5;82m\]
# Function to generate git branch
\`parse_git_branch\`
# Plain color
\[\e[m\]
# Colon symbol
: