RA improperly picking up ignore in `#[cfg_attr(miri, ignore)]` on tests in VS Code

[John-Robbins]

rust-analyzer version: 0.3.2593-standalone (XXXXXXXXXX 2025-08-25) [/Users/somedude/.vscode/extensions/rust-lang.rust-analyzer-0.3.2593-darwin-arm64/server/rust-analyzer]
VS Code version: Version: 1.103.2 (Universal)

In my project, I run Miri frequently and with its limitations, it's important to mark the tests that Miri can't handle with the #[cfg_attr(miri, ignore)] attribute. Unfortunately, rust-analyzer, picks up the ignore when it should not because the cfg_attr is not active. When clicking on the Run Test or Debug link above the test and the test does not run because rust-analyzer thinks it is ignored.

Steps to Reproduce

1. Set up an test on a project. The reproduces for unit and integration tests.

2. Add the #[cfg_attr(miri, ignore)] attribute to a test like the following.

   # [test]
   # [cfg_attr(miri, ignore)]
   fn quit_test() {
   // --snip--snip--snip    

3. Open the test in the latest Visual Studio Code and the latest rust-analyzer installed.

4. Go to the test with the Miri attribute and click the "Run test" link in the editor.

5. Rust-analyzer will run the test with the following command.

   cargo test --package rl --test harness_tests -- quit_test --exact --show-output --ignored
   

6. This shows how the --ignored switch is being added even though the cfg_attr is not applicable.

7. Remove the # [cfg_attr(miri, ignore)] in the code.

8. Click the "Run test" link.

9. The test command no longer shows the --ignored, and the test runs correctly.

   cargo test --package rl --test harness_tests -- quit_test --exact --show-output
   

Ideally, rust-analyzer would take into account the build configuration and discard the ignore if the build configuration is not active.

[ChayimFriedman2]

The miri cfg is active by default, You can set rust-analyzer.cargo.cfgs to disable it.

[John-Robbins]

👍 Thanks! I'm newish to Rust and didn't realize RA set Miri.