Rust tests should be inside of the Rust crate

[kylebarron]

There seem to be various problems when having the rust tests at a separate top-level directory tests/ instead of inside of src/. For example I have vscode set to format on save, but because the tests aren't part of the crate, that doesn't work. And I can't import from a util.rs file with crate::util because there is no crate that tests/ is a part of.

So we should move rust tests to be inside of src/ but we should keep the files at the top level so they can be accessed by both Rust and Python tests

[kylebarron]

[weiji14]

It should be possible to have a top-level tests/ folder according to https://doc.rust-lang.org/book/ch11-03-test-organization.html#the-tests-directory. In your tests/mod.rs file, do you have a line that says mod ome_tiff;?

[kylebarron]

Really what I'm hitting here, is that it doesn't seem possible to import functions from other files in the test mod

I.e. if you try to have a utils.rs and move open_remote_tiff there, then it gives

unresolved import `crate::utils`
could not find `utils` in the crate root

even though I added

mod utils;

into mod.rs.