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//! Calling back into the same cycle from your cycle recovery function _can_ work out, as long as
//! the overall cycle still converges.
mod common;
use common::{DatabaseWithValue, ValueDatabase};
#[salsa::tracked]
fn fallback_value(db: &dyn ValueDatabase) -> u32 {
query(db) + db.get_value()
}
#[salsa::tracked(cycle_fn=cycle_fn, cycle_initial=cycle_initial)]
fn query(db: &dyn ValueDatabase) -> u32 {
let val = query(db);
if val < 5 {
val + 1
} else {
val
}
}
fn cycle_initial(_db: &dyn ValueDatabase) -> u32 {
0
}
fn cycle_fn(db: &dyn ValueDatabase, _value: &u32, _count: u32) -> salsa::CycleRecoveryAction<u32> {
salsa::CycleRecoveryAction::Fallback(fallback_value(db))
}
#[test]
fn converges() {
let db = DatabaseWithValue::new(10);
assert_eq!(query(&db), 10);
}
#[test]
#[should_panic(expected = "fallback did not converge")]
fn diverges() {
let db = DatabaseWithValue::new(3);
query(&db);
}
|
