How do I set the RUST_TEST_TASKS environment variable?

Question

I am attempting to write tests for my Rust program. Normally, these tests are run in parallel but I want to run them sequentially. I looked around and I can set this environment variable RUST_TEST_TASKS=1, but I am not sure where to do that.

Answer 1

The environment variable is actually RUST_TEST_THREADS

Answer 2

I think what they mean is setting the environment variables in the shell the test runner is running in, such as:

RUST_TEST_TASKS=1 ./my-test-runner

or exporting it:

export RUST_TEST_TASKS=1
./my-test-runner