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Sometimes we need to write mojo goals that do not require a MavenProject. The install-file goal form the maven-install-plugin is a good example.
For now we cannot use mojo-executor in such goals because ExecutionEnvironment requires a non-null MavenProject.
I'm not sure it's even feasible but would be very nice.
I think it is feasible. We only need the MavenProject in order to look for remote plugin repositories.
As a workaround, it should be possible to construct an empty MavenProject and pass that in.
I'll leave this open for now and look at improving the API and adding some tests in the future.
Looking forward to it. Thanks.