error: multiple unused formatting arguments
 --> tests/ui/invalid_err_context_args.rs:5:29
  |
5 |     #[br(err_context("too", "many", "arguments"))]
  |                      -----  ^^^^^^  ^^^^^^^^^^^ argument never used
  |                      |      |
  |                      |      argument never used
  |                      multiple missing formatting specifiers

error: err_context requires a value but none were given
  --> tests/ui/invalid_err_context_args.rs:11:10
   |
11 |     #[br(err_context())]
   |          ^^^^^^^^^^^

error: format string expected
  --> tests/ui/invalid_err_context_args.rs:17:22
   |
17 |     #[br(err_context(a, b))]
   |                      ^