Empty Continuation Line in Dockerfile

Warning thrown in hab pkg export container:

$ sudo hab pkg export container sirajrauff/sample-node-app
» Building a container image with: sirajrauff/sample-node-app
Ω Creating build root in /tmp/.tmplBNSju
Ω Creating root filesystem
Ω Creating artifact cache symlink
Ω Creating key cache symlink
» Installing core/hab
[..]
☒ Deleting artifact key symlink
☒ Deleting artifact cache symlink
Ω Creating user 'hab' in /etc/passwd
Ω Creating group 'hab' in /etc/group
Ω Creating entrypoint script
Ω Creating image Dockerfile
Ω Creating image
Sending build context to Docker daemon  485.1MB
[WARNING]: Empty continuation line found in:
    RUN     find /hab -type d -exec chmod g=u {} \; &&     mkdir /root && chmod 750 root &&     mkdir /tmp && chmod 1777 /tmp &&     mkdir -p /var/tmp && chmod 1777 /var/tmp &&     mkdir -p /.hab/cache/keys && chmod -R 770 /.hab
[WARNING]: Empty continuation lines will become errors in a future release

Managed to pull the Dockerfile:

FROM scratch
ENV PATH /bin
ADD rootfs/hab /hab

# Contains all our busybox userspace links, hab binary link, and any user
# package binary links
#
# TODO: The creation of this directory and the links therein could be
# executed directly in this Dockerfile, in a series of commands
# executed at the beginning of the following RUN directive. This could
# simplify Rust code, as well as save an additional layer.
COPY rootfs/bin /bin

RUN \
    # Remember, in order to be able to run a Supervisor as non-root,
    # we must at least have write access to the /hab directory. If you
    # further wish to run an *updating* Supervisor (or one that
    # updates its services), you will (generically) require write
    # access to everything under `/hab/pkgs` as well.
    #
    # (One final note: we run this `find` command *after* we set up /bin
    # to avoid having to call our busybox binary directly.)
    find /hab -type d -exec chmod g=u {} \; && \
    # Create the minimum amount of directories for things to work.
    #
    # /tmp is particularly required for the Supervisor / Launcher
    # communication pipe.
    mkdir /root && chmod 750 root && \
    mkdir /tmp && chmod 1777 /tmp && \
    mkdir -p /var/tmp && chmod 1777 /var/tmp && \

    # This is currently needed in order for non-root containers to
    # function... this ends up being their home directory, and we
    # expect to find key cache directory there right now.
    mkdir -p /.hab/cache/keys && chmod -R 770 /.hab

# Ensure our custom /etc content (notably `passwd` and `group` files,
# but also our linked cacerts in /etc/ssl) are present.
#
# TODO: The creation of everything in this directory could potentially
# be taken entirely out of Rust and implemented here in the Dockerfile.
COPY rootfs/etc /etc
COPY rootfs/init.sh /init.sh

EXPOSE 9631 
RUN HAB_FEAT_OFFLINE_INSTALL=ON \
        HAB_LICENSE=accept-no-persist \
    /hab/pkgs/core/hab/1.6.288/20210402191717/bin/hab pkg install sirajrauff/sample-node-app/0.1.0/20210412160756
ENTRYPOINT ["/init.sh"]
CMD ["run", "sirajrauff/sample-node-app"]

I imagine this warning/future error is concerning the RUN \ line? or the line break after the mkdir -p /var/tmp?

Aha! Link: https://chef.aha.io/features/APPDL-18

habitat-sh / habitat

Empty Continuation Line in Dockerfile #8166