Check out $sha after a clone.
@@ -8,6 +8,7 @@ function checkout_at() {
repo=$1; url=$2; sha=$3
if [ ! -d "$repo" ]; then
git clone "https://github.com/$url" "$repo"
+ git fetch && git reset --hard "$sha"
else
pushd "$repo" && git fetch
git reset --hard "$sha"
