Squash commits on current branch that are different from the develop branch and rebase to the develop branch

git-squash.sh

#!/bin/sh

# Colors
C_RESET="\033[0m"
C_ERROR="\033[0;97m\033[41m"
C_GOLD="\033[0;33m"
C_CYAN="\033[0;36m"
C_GREEN="\033[0;32m"

display_error () {
    echo $C_ERROR$1$C_RESET
};

display_prompt () {
    echo $C_GOLD$1" "$C_RESET
}

display_yn_prompt () {
    echo $C_GOLD$1" [y/N] "$C_RESET
}

display_sys_message () {
    echo $C_CYAN$1$C_RESET
}

blank_line () {
    echo ""
}

check_for_git_repo () {
    display_sys_message "Checking for git repo..."

    INSIDE_REPO="$(git rev-parse --is-inside-work-tree 2>/dev/null)"

    if [[ ! $INSIDE_REPO ]]; then
        display_error "Not inside a git repo! Exiting."
        exit 2
    fi

    display_sys_message "Git repo found."
}

retrieve_branch () {
    display_sys_message "Retrieving branch name..."
    BRANCH=$(git rev-parse --abbrev-ref HEAD)
    display_sys_message "Branch name retrieved."
}

confirm_branch () {
    read -p "$(display_yn_prompt "Is "$C_GREEN$BRANCH$C_GOLD" the correct branch?")" CONFIRM_BRANCH

    if [[ ! $CONFIRM_BRANCH =~ ^[Yy]$ ]]; then
        display_error "Please check out the correct branch first. Exiting."
        exit 3
    fi
}

checkout_develop () {
    display_sys_message "Checking out the "$C_GREEN"develop"$C_CYAN" branch..."
    git checkout develop
}

pull_develop () {
    display_sys_message "Pulling latest remote version of the "$C_GREEN"develop"$C_CYAN" branch..."
    git pull
}

checkout_source () {
    display_sys_message "Checking out the "$C_GREEN$BRANCH$C_CYAN" branch..."
    git checkout $BRANCH
}

resolve_hash () {
    display_sys_message "Determining the hash of first commit on the branch (the final commit that will be squashed)..."
    HASH=$(git rev-list develop..$BRANCH | tail -n 1)
    HASH=${HASH:0:8}
    display_sys_message "Found commit "$C_GREEN$HASH$C_CYAN" as the first commit on the branch."
}

confirm_hash () {
    read -p "$(display_yn_prompt "Is "$C_GREEN$HASH$C_GOLD" the hash of the first commit on this branch?")" CONFIRM_HASH

    if [[ ! $CONFIRM_HASH =~ ^[Yy]$ ]]; then
        display_error "Wrong hash found. Exiting."
        exit 6
    fi
}

resolve_num () {
    display_sys_message "Determining the number of commits to squash..."
    NUM=$(git rev-list --count develop..$BRANCH)
    display_sys_message $C_GREEN$NUM$C_CYAN" commit(s) found to squash."
}

confirm_soft_reset () {
    read -p "$(display_yn_prompt "Conduct soft reset to squash "$C_GREEN$NUM$C_GOLD" commit(s)?")" CONFIRM_RESET

    if [[ ! $CONFIRM_RESET =~ ^[Yy]$ ]]; then
        display_error "Reset aborted. Exiting."
        exit 4
    fi
}

perform_soft_reset () {
    display_sys_message "Performing soft reset of "$C_GREEN$NUM$C_CYAN" commit(s)..."
    git reset --soft HEAD~$NUM
    display_sys_message "Soft reset of "$C_GREEN$NUM$C_CYAN" commit(s) completed."
}

confirm_squash () {
    read -p "$(display_yn_prompt "Complete squashing of "$C_GREEN$NUM$C_GOLD" commit(s) (all future steps are destructive and cannot be undone)?")" CONFIRM_SQUASH

    if [[ ! $CONFIRM_SQUASH =~ ^[Yy]$ ]]; then
        display_sys_message "Reverting soft reset of "$C_GREEN$NUM$C_CYAN" commit(s)..."
        git reset HEAD@{1}
        display_sys_message "Revert completed."
        display_error "Squash aborted. Exiting."
        exit 5
    fi
}

craft_commit_message () {
    read -p "$(display_prompt "What is your commit message?")" MESSAGE

    read -p "$(display_prompt "What is the associated JIRA ticket(s), if any?")" JIRA

    display_sys_message "Compiling commit message..."
    GITLOG=$(git log --format=%B --reverse HEAD..HEAD@{1})

    if [[ JIRA ]]; then
        MESSAGE=$MESSAGE$'\n\n'"JIRA TICKET(S)"$'\n'"--------------"
    fi

    MESSAGE=$MESSAGE$'\n\n'"PREVIOUS COMMIT MESSAGES"$'\n'"------------------------"$'\n\n'$GITLOG
    display_sys_message "Commit message compiled."
}

commit_changes () {
    display_sys_message "Committing squash commit..."
    git commit -m"$MESSAGE"
    display_sys_message "Squash commit committed."
}

perform_rebase () {
    display_sys_message "Performing rebase..."
    git rebase develop
    display_sys_message "Rebase complete..."
}

# ENSURE WITHIN GIT DIRECTORY
check_for_git_repo

blank_line

# RETRIEVE CURRENT BRANCH
retrieve_branch

blank_line

# CONFIRM CORRECT BRANCH
confirm_branch

blank_line

# CHECK OUT DEVELOP
checkout_develop

blank_line

# PULL LATEST DEVELOP FROM ORIGIN
pull_develop

blank_line

# CHECK OUT SOURCE
checkout_source

blank_line

# GET THE HASH OF THE FINAL COMMIT TO SQUASH
resolve_hash

blank_line

# CONFIRM THE HASH IS CORRECT
confirm_hash

blank_line

# GET NUMBER OF COMMITS TO SQUASH
resolve_num

blank_line

# CONFIRM SOFT RESET
confirm_soft_reset

blank_line

# PERFORM SOFT RESET
perform_soft_reset

blank_line

# CONFIRM SQUASH
confirm_squash

blank_line

# CRAFT COMMIT MESSAGE
craft_commit_message

blank_line

# COMMIT CHANGES
commit_changes

blank_line

# PERFORM REBASE
perform_rebase

blank_line

exit 0