tests/run-make/overwrite-input/rmake.rs

// An attempt to set the output `-o` into a directory or a file we cannot write into should indeed
// be an error; but not an ICE (Internal Compiler Error). This test attempts both and checks
// that the standard error matches what is expected.
// See https://github.com/rust-lang/rust/issues/66530

use run_make_support::{diff, rustc};

fn main() {
    let file_out = rustc().input("main.rs").output("main.rs").run_fail().stderr_utf8();
    let folder_out = rustc().input("main.rs").output(".").run_fail().stderr_utf8();
    diff().expected_file("file.stderr").actual_text("actual-file-stderr", file_out).run();
    diff().expected_file("folder.stderr").actual_text("actual-folder-stderr", folder_out).run();
}