Some test in a project fail in release mode cargo test --release because there are debug_asserts that are expected to panic for those tests. Is there a way to keep debug_asserts on but use the release profile when running tests?

Some test in a project fail in release mode cargo test --release because there are debug_asserts that are expected to panic for those tests. Is there a way to keep debug_asserts on but use the release profile when running tests?

• rust
• rust-cargo

1 Answer 1

If your code should panic in --release mode, then use a normal assert! instead of a debug_assert!.

If your code shouldn't panic in --release mode but don't want cargo test --release to report a failure, then you can ignore the test:

#[test]
#[cfg_attr(not(debug_assertions), ignore)]
fn my_test() { ... }

If you really want to keep debug_assert! for testing while getting other effects from --release, then you enable the configuration via rustflags from an environment variable (or other config):

RUSTFLAGS="-C debug-assertions" cargo test --release

Or you can modify the release profile or create a custom profile:

# Cargo.toml

[profile.release]
debug-assertions = true

# or

[profile.dev-optimized]
inherits = "dev"
opt-level = 3

cargo test --profile=dev-optimized