Set environment variables temporarily.
This crate is useful for testing with different environment variables that should not interfere.
This code started as a small test helper written by @fabian-braun and @nbaztec and published by @fabian-braun on StackOverflow. @vmx found it useful and took the time to make it a proper crate.
temp_env::with_var("MY_ENV_VAR", Some("production"), || {
// Run some code where `MY_ENV_VAR` set to `"production"`.
});
temp_env::with_vars(
vec![
("FIRST_VAR", Some("Hello")),
("SECOND_VAR", Some("World!")),
],
|| {
// Run some code where `FIRST_VAR` is set to `"Hello"` and `SECOND_VAR` is set to
// `"World!"`.
}
);
temp_env::with_vars(
vec![
("FIRST_VAR", Some("Hello")),
("SECOND_VAR", None),
],
|| {
// Run some code where `FIRST_VAR` is set to `"Hello"` and `SECOND_VAR` is unset (even if
// it was set before)
}
);
This crate sets and unsets environment variables for the currently running (Rust) process.
It leverages std::env::set_var
.
The provided functions temp_env::with_*
provide the following features:
- Avoid interference when running concurrently
- Reset previously set env variables back to their original value upon completion, also in case of panic
- Temporarily unsetting env variables
Note that the crate makes use of a singleton mutex to avoid side effects between concurrently running tests. This may impact the degree of concurrency in your test execution.
This project is licensed under either of
- Apache License, Version 2.0, (LICENSE-APACHE) or https://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)
at your option.