On systems where `coreutils` are built with `--enable-single-binary=symlinks` like Nix,
`/usr/bin/env` is symlinked to `/usr/bin/coreutils` and uses `argv[0]` to determine which program to run.
Since the `test-cli-extensions.sh` created a new symlink named `ostree-env`,
coreutils would be confused about the utility to choose, so running it would fail:
ostree-env: unknown program ‘ostree-env’
Try 'ostree-env --help' for more information.
Fixes: https://github.com/ostreedev/ostree/issues/2553
In fixing https://github.com/coreos/rpm-ostree/pull/3323
I felt that it was a bit ugly we're installing `/usr/bin/ostree-container`.
It's kind of an implementation detail. We want users to use
`ostree container`.
Let's support values outside of $PATH too.
For example, this also ensures that TAB completion for `ost` expands
to `ostree ` with a space.
This updates the test logic for CLI extensions, actually checking
for functional output from the subcommand.
It also cleans up some environmental leftover.
This adds some logic to detect and dispatch unknown subcommands to
extensions available in `$PATH`. Additional commands can be
implemented by adding relevant `ostree-$verb` binaries to the system.
As an example, if a `/usr/bin/ostree-extcommand` extension is provided,
the execution of `ostree extcommand --help` will be dispatched to that
as `ostree-extcommand extcommand --help`.
Jan Tojnar
Colin Walters
Luca BRUNO