`git fetch --tags --unshallow`, run as part of the CI for `git
describe` to do the right thing, ran into the error:
```
! [rejected] mosh-1.4.0-rc0 -> mosh-1.4.0-rc0 (would clobber existing tag)
```
This is because mosh uses annotated tags, whereas the initial fetch
command run by actions/checkout@v2 ends up creating an *unannotated*
tag of the same name.
This means that any time the release CI runs, it would fail.
The resolution is straightforward: --force so that the line becomes
```
t [tag update] mosh-1.4.0-rc0 -> mosh-1.4.0-rc0
```
and the annotation is brought in.
The previous CI attemtped to use Homebrew for builds, but
unfortunately Homebrew has dropped support for universal packages aka
multiarch (fat) binaries. This means that in order to build an arm64 +
x86_64 package, macports has to be used instead of homebrew.
Unlike Homebrew, MacPorts is not installed by default on the GitHub
Actions runners, so we need to install it ourselves. This means
managing our own instance of the cache, which itself produces
challenges as the `gtar` binary run by the action doesn't have enough
permissions to restore the MacPorts checkout. So we have to shim gtar
with a sudo wrapper.
With this commit, we produce a Mosh package that works on macOS 11.0
and newer, on both arm64 and x86_64 architectures. The protobuf
library is statically linked, but all other libraries are provided by
the system.
This change ports the Travis CI release workflow for macOS to Github
Actions. Note that while this is functionally identical to the
previous Travis CI flow, no work has been done to update the macOS
build scripts to build for arm64.
This Github Actions workflow uses a Linux-based running to create the
release tarball for mosh. This is necessary since mosh does not check
in the autoconf/automake generated files, so the default release
action source download is missing files that are needed for
distributions that use the upstream-provided ./configure script.
Alex Chernyakhovsky