rust-revision is not respected

[Mark Shuttleworth]

snapcraft help rust suggests that I can get a particular revision of rust with the 'rust-revision' keyword. However, a snapcraft.yaml like this:

    rust-channel: 'nightly'
    rust-revision: 'nightly-2016-12-16'

results in this:

Downloading 'rustup.sh'[=================================================================================================================================================================================================================================] 100%
/home/mark/software/snaps/alacritty-snap/parts/alacritty/rust/rustup.sh --prefix=/home/mark/software/snaps/alacritty-snap/parts/alacritty/rust --disable-sudo --save
rustup: gpg available. signatures will be verified
rustup: downloading manifest for 'stable'

[Mark Shuttleworth (sabdfl)]

Perhaps the issue is here:

        self.run(["%s" % self._rustup,
                  "--prefix=%s" % self._rustpath,
                  "--disable-sudo", "--save"])

[Sergio Schvezov (sergiusens)]

https://github.com/snapcore/snapcraft/pull/1034