Absolute paths in stderr files

[tyilo]

I'm have setup ui_test in my project, however my the generated .stderr files contains absolute paths.
I would expect them to contain relative paths, so that the output doesn't depend on the local path to the repository on the machine running the tests.

I have an example project here: https://github.com/tyilo/ui-tests-test

Running BLESS=1 cargo test creates the tests/fail/wrong_arg.stderr file which contains the absolute path to src/lib.rs:

error[E0308]: mismatched types
 --> tests/fail/wrong_arg.rs:5:9
  |
5 |     foo(1i32);
  |     --- ^^^^ expected `u32`, found `i32`
  |     |
  |     arguments to this function are incorrect
  |
note: function defined here
 --> /tmp/ui-tests-test/src/lib.rs:1:8
  |
1 | pub fn foo(v: u32) {
  |        ^^^
help: change the type of the numeric literal from `i32` to `u32`
  |
5 -     foo(1i32);
5 +     foo(1u32);
  |

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0308`.

[tyilo]

Adding

//@normalize-stderr-test: "/[^ ]*/src/lib.rs" -> "../src/lib.rs"

to the top of the test file fixes it for this specific case.

However, it seems like there should be a better way?