List aliases in a table like view

README.md

List your aliases in a table like view.

Save list_aliases.sh in your home directory in a bin directory. Create a file named .aliases in your home directory. Add all your aliases like this:

alias ..="cd .." # Navigate one directory down
alias ...="cd ../.." # Navigate two directories down
alias ip="ipconfig getifaddr en0" # Get local ip
alias gen-pwd="pwgen -s -N 1 -cny 32" # Generate password with 32 length

Next include your new .aliases file in your ~/.bash_profile (create it, if necessary):

source ~/.aliases
alias aliases='bash ${HOME}/bin/list_aliases.sh'

Restart terminal and type aliases. Now you can see a table with all your aliases and comments.

list_aliases.sh

#!/bin/bash

INPUT_FILE="${HOME}/.aliases"

COMMAND_COLOR="\033[38;5;114m"
COMMENT_COLOR="\033[38;5;245m"
COLOR_RESET="\033[0m"

###
# @param number of characters to show, eg 1
# @param character to show, eg "-" 
###
printWhitespaceCharacter () {
    for (( c=0; c<=$1; c++ ))
    do
       echo -n "$2"
    done
}

###
# Get longest command and comment
###
getMaxLengths () {
    MAX_COMMAND_LENGTH=0
    MAX_COMMENT_LENGTH=0

    while IFS= read -r line
    do
        LINE_WITHOUT_ALIAS=$(echo "$line"| sed 's/[^ ]* *//')
        COMMAND=$(echo "$LINE_WITHOUT_ALIAS" | sed 's/=.*//g')
        COMMENT=$(echo "$LINE_WITHOUT_ALIAS" | sed 's/.*#//g')

        COMMAND_LENGTH=${#COMMAND}
        COMMENT_LENGTH=${#COMMENT}

        if [ $COMMAND_LENGTH -gt $MAX_COMMAND_LENGTH ]; then
            MAX_COMMAND_LENGTH=${COMMAND_LENGTH}
        fi

        if [ $COMMENT_LENGTH -gt $MAX_COMMENT_LENGTH ]; then
            MAX_COMMENT_LENGTH=${COMMENT_LENGTH}
        fi
    done < "$INPUT_FILE"
}

###
# Print separator based on longest command and comment
###
printSeparatorLine () {
    COMMAND_SEPARATOR=`expr $MAX_COMMAND_LENGTH`
    COMMENT_SEPARATOR=`expr $MAX_COMMENT_LENGTH + 2`

    echo "+$(printWhitespaceCharacter $COMMAND_SEPARATOR "-")$(printWhitespaceCharacter $COMMENT_SEPARATOR "-")+"
}

getMaxLengths

###
# Print headline
###
printHead () {
    # Substract characters for "COMMAND" and " COMMENT"
    COMMAND_WHITESPACE_LENGTH=`expr $MAX_COMMAND_LENGTH - 7`
    COMMENT_WHITESPACE_LENGTH=`expr $MAX_COMMENT_LENGTH - 8`

    echo ""
    echo "$(printSeparatorLine)"
    echo "| COMMAND$(printWhitespaceCharacter $COMMAND_WHITESPACE_LENGTH " ")| COMMENT$(printWhitespaceCharacter $COMMENT_WHITESPACE_LENGTH " ")|"
    echo "$(printSeparatorLine)"
}

echo "$(printHead)"

###
# Run script
###
while IFS= read -r line
do

    LINE_WITHOUT_ALIAS=$(echo "$line"| sed 's/[^ ]* *//')
    COMMAND=$(echo "$LINE_WITHOUT_ALIAS" | sed 's/=.*//g')
    COMMENT=$(echo "$LINE_WITHOUT_ALIAS" | sed 's/.*#//g')

    # COMMAND
    THIS_COMMAND_LENGTH=$(echo ${#COMMAND})
    COMMAND_LENGTH=`expr $MAX_COMMAND_LENGTH - $THIS_COMMAND_LENGTH - 1`

    echo -ne "| ${COMMAND_COLOR}${COMMAND}${COLOR_RESET} "

    # Fill up with whitespace
    printWhitespaceCharacter $COMMAND_LENGTH " "

    # COMMENT
    THIS_COMMENT_LENGTH=$(echo ${#COMMENT})
    COMMENT_LENGTH=`expr $MAX_COMMENT_LENGTH - $THIS_COMMENT_LENGTH - 1`

    echo -ne "|${COMMENT_COLOR}${COMMENT}${COLOR_RESET} "

    # Fill up with whitespace
    printWhitespaceCharacter $COMMENT_LENGTH " "
    echo "|"

    echo $(printSeparatorLine)

done < "$INPUT_FILE"

echo ""