temp-env

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.

Example

``rust temp_env::with_var("MY_ENV_VAR", Some("production"), || { // Run some code whereMYENVVARset to"production"`. });

tempenv::withvars( vec![ ("FIRSTVAR", Some("Hello")), ("SECONDVAR", Some("World!")), ], || { // Run some code where FIRST_VAR is set to "Hello" and SECOND_VAR is set to // "World!". } );

tempenv::withvars( vec![ ("FIRSTVAR", Some("Hello")), ("SECONDVAR", None), ], || { // Run some code where FIRST_VAR is set to "Hello" and SECOND_VAR is unset (even if // it was set before) } ); ```

How does it work?

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.

License

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.