Runnables: Extra Args sets Args instead of Extra Args

rust-analyzer version: (eg. output of "rust-analyzer: Show RA Version" command, accessible in VSCode via Ctrl/⌘+Shift+P)
rust-analyzer version: 0.3.1221-standalone

rustc version: (eg. output of rustc -V)

rustc 1.63.0 (4b91a6ea7 2022-08-08)

relevant settings: (eg. client settings, or environment variables like CARGO, RUSTUP_HOME or CARGO_HOME)
RUST_TEST_THREADS=1 (workaround set via Runnables:Env) others unset

I might be wrong, but it seems to me that:

The description says:
Additional arguments to be passed to cargo for runnables such as tests or binaries. For example, it may be --release.

However, there seems to be no possibility to set values, i.e. arguments that appear after --.

The rust-analyzer source code speaks of args and extra_args.

match kind

In particular, I tried to set the test-threads=1 extra argument, which fails as it is inserted before the --.
The workaround is to use the older environment variable RUST_TEST_THREADS, but the command line argument is preferred as far as I understood.

Have I missed something, or is this a possible issue?

Start in crates/rust-analyzer/src/cargo_target_spec.rs, especially the handling of args and extra_args linked in the report. Reproduce a runnable with an extra argument such as test-threads=1 and verify that the generated command places it after -- rather than among Cargo's arguments.