git-commands-for-pull-request.sh

# https://help.github.com/en/github/getting-started-with-github/fork-a-repo
# https://help.github.com/en/github/collaborating-with-issues-and-pull-requests/syncing-a-fork

FORKREPO="$1"
ORIGINREPO="$2"
WORKDIR="$3"

git clone "$FORKREPO" "$WORKDIR" # clone forked repo
cd "$WORKDIR"
git remote -v # confirm current configuration
git remote add upstream "$ORIGINREPO" # add upstream
git remote -v # confirm if upstream is added

git fetch upstream # update local repo
git checkout master # switches to branch 'master'
git merge upstream/master # merge from upstream