gitExamples.sh

#!/bin/bash
# shellcheck disable=SC2015

repoDir="$1"
example="$2"

function die() {
    echo -e "$@" >&2
    exit 1
}

if [ -d "$repoDir" ]; then
    die "! You need to enter an non-existing path to\n" \
        "  the repo you want to create.\n" \
        "  Path '$repoDir' exists"
fi

function setupRepo() {
    mkdir -p "${repoDir}" || true

    echo "Creating repository at '$repoDir'"
    git init "$repoDir" && cd "$repoDir" ||
        die "! Git init failed"
    git commit --allow-empty -m "Init" ||
        die "! Could not create init"
}

function addFileCommit() {
    echo "changes $1.1" >>"$1.1" && echo "changes $1.2" >>"$1.2" && git add .
    msg="Added file $1"
    [ -n "$2" ] && msg="$msg $2"
    git commit -a -m "$msg"
}

function finalize() {
    echo "Repository succesfully setup at '$repoDir'"
    echo "Try your stuff now! :-)"
}

function showCommits() {
    echo "Current history is:"
    git --no-pager log \
        --color \
        --graph \
        --pretty=format:'%Cred%h%Creset - %s %C(yellow)%d%Creset' \
        --abbrev-commit \
        --branches
    echo
}

function setupWrongCommittedFiles() {
    setupRepo || die "! Setup failed"

    git checkout -b feature

    # Write the check file
    cat <<EOF >check.sh
#!/bin/bash
set -e
trap 'echo "Your solution is not correct!"' ERR
git checkout feature &>/dev/null
files=\$(git --no-pager log feature --oneline |
        cut -d ' ' -f 1 |
        xargs -n 1 git diff-tree --no-commit-id --name-only -r)
echo "\$files" | grep -q 'W.2' && false
echo "Your solution is correct: no 'W.2' file found!"
EOF
    chmod u+x check.sh
    git add . && git commit -a -m "Test your solution"

    # Wrong commited files -> rebasing
    addFileCommit "A"
    addFileCommit "B"
    addFileCommit "W" "(Wrong committed file)"
    addFileCommit "C"
    addFileCommit "D"
    addFileCommit "W" "(Wrong changes)"
    showCommits

    finalize || die "! Finalize failed"
}

if [ "$example" = "ex-wrong-committed-files" ]; then
    setupWrongCommittedFiles
else
    die "! No such example '$example'\n" \
        "  Examples are:\n" \
        "    - ex-wrong-committed-files"
fi