salsa/tests/specify-only-works-if-the-key-is-created-in-the-current-query.rs
Niko Matsakis daaa78056a switch to new database design
Under this design, *all* databases are a
`DatabaseImpl<U>`, where the `U` implements
`UserData` (you can use `()` if there is none).

Code would default to `&dyn salsa::Database` but
if you want to give access to the userdata, you
can define a custom database trait
`MyDatabase: salsa::Databse` so long as you

* annotate `MyDatabase` trait definition of
  impls of `MyDatabase` with `#[salsa::db]`
* implement `MyDatabase` for `DatabaseImpl<U>`
  where `U` is your userdata (this could be a
  blanket impl, if you don't know the precise
  userdata type).

The `tests/common/mod.rs` shows the pattern.
2024-07-28 12:47:50 +00:00

45 lines
1.1 KiB
Rust

//! Test that `specify` only works if the key is a tracked struct created in the current query.
//! compilation succeeds but execution panics
#![allow(warnings)]
#[salsa::input]
struct MyInput {
field: u32,
}
#[salsa::tracked]
struct MyTracked<'db> {
field: u32,
}
#[salsa::tracked]
fn tracked_struct_created_in_another_query<'db>(
db: &'db dyn salsa::Database,
input: MyInput,
) -> MyTracked<'db> {
MyTracked::new(db, input.field(db) * 2)
}
#[salsa::tracked]
fn tracked_fn<'db>(db: &'db dyn salsa::Database, input: MyInput) -> MyTracked<'db> {
let t = tracked_struct_created_in_another_query(db, input);
if input.field(db) != 0 {
tracked_fn_extra::specify(db, t, 2222);
}
t
}
#[salsa::tracked(specify)]
fn tracked_fn_extra<'db>(_db: &'db dyn salsa::Database, _input: MyTracked<'db>) -> u32 {
0
}
#[test]
#[should_panic(
expected = "can only use `specify` on salsa structs created during the current tracked fn"
)]
fn execute_when_specified() {
let mut db = salsa::DatabaseImpl::new();
let input = MyInput::new(&db, 22);
let tracked = tracked_fn(&db, input);
}