# Host integration tests

All host integration tests share the `it` executable. Each module keeps its former file name.

```sh
cargo test -p sausage --test it
cargo test -p sausage --test it -- chain::
cargo test -p sausage --test it -- --test-threads=1
```

Use `nix develop -c` and the required build slot wrapper for these commands.
Set `CARGO_TARGET_DIR` to your executor's target directory.

The journal timing benchmark keeps its 10% threshold but does not run in the default suite.
Run it by hand on an idle machine:

```sh
cargo test --release -p sausage --test it -- --ignored undo_cost
```

Add new modules under `host/tests/it/` and declare them in `it/main.rs`.
Cargo does not discover separate test executables in `host/tests/`.
Fixture sources remain in `builder-fixture/`.
The bundle-copy regression preserves relative symlink targets, including broken links.

`common.rs` shares the target lookup and the cached userland Git build.
The goal/questions and harness API fixtures copy the complete extension tree through its shared helper.
A shared mutex protects the cwd-init output and the brush checkout during fixture builds.
The cwd-init build runs at most once per process when its output is absent.
The first parallel run reproduced a collision when two compiler processes wrote `init.o`.
Tests use temporary worlds and ephemeral listener ports.
Child processes receive environment variables through `Command`, not through changes to the test process.
SIGKILL parents use fully qualified test filters with `--exact`.

The `hook::hook_git` and `hook_git` registrations both existed before this move.
Both remain as wrappers around one shared helper to preserve the test count.
The shared `hook_guest` module now builds its fixture once per process.