Running cargo test with any parameter filters out all tests

I think I'm having the problem outlined in this issue.
In short I can successfully execute any subgroup of tests matching sub_string in the test name by running cargo test sub_string -- --nocapture myparam. (The last parameter is necessary to avoid hardcoding or setting an env variable for an auth token.)
Running cargo test -- --nocapture myparam, however, filters out all tests.
Running cargo test myparam filters out all tests.
Running cargo test runs all tests but of course they fail without the auth token.

I don't see any link with the vim issue and what you write.
I'm not sure I would recommend using a parameter over a variable. There is no telling if the test command line will change in the future.
Can see options using cargo test -- --help
If insist on sending a token as param then could hide it after --skip so all tests run.

I don't like littering the ENV with variables that are not necessary for my system. I'm the only person using this crate, so the brittleness of specifying the order of args is of no consequence to me.
What do you mean "hide it after --skip"?