Support for cargo rustc to build tests?

[tomjakubowski]

Is it feasible to support the new cargo rustc command as an alternative to rustc for running compile tests? It would mean significantly less pain specifying paths to dependencies. I tried to make it work with the existing options in compiletest::common::Config but to no avail, unfortunately.

(If you intend to keep the source of this crate as close to the upstream source in rust-lang/rust as possible, then this probably isn't an option, but I thought I'd ask anyway!)

[tomjakubowski]

Oh, shoot. I guess cargo rustc doesn't actually support compiling arbitrary source files. Phooey.