generic salsa algo

1 files changed, 153 insertions, 0 deletions

diff --git a/crates/salsa/tests/integration.rs b/crates/salsa/tests/integration.rs
new file mode 100644
index 000000000..7241eca38
--- /dev/null
+++ b/crates/salsa/tests/integration.rs
@@ -0,0 +1,153 @@
+extern crate salsa;
+use std::{
+    sync::Arc,
+    collections::hash_map::{HashMap, DefaultHasher},
+    any::Any,
+    hash::{Hash, Hasher},
+};
+
+type State = HashMap<u32, String>;
+const GET_TEXT: salsa::QueryTypeId = salsa::QueryTypeId(1);
+const GET_FILES: salsa::QueryTypeId = salsa::QueryTypeId(2);
+const FILE_NEWLINES: salsa::QueryTypeId = salsa::QueryTypeId(3);
+const TOTAL_NEWLINES: salsa::QueryTypeId = salsa::QueryTypeId(4);
+
+fn mk_ground_query<T, R>(
+    state: &State,
+    params: &(Any + Send + Sync + 'static),
+    f: fn(&State, &T) -> R,
+) -> (Box<Any + Send + Sync + 'static>, salsa::OutputFingerprint)
+where
+    T: 'static,
+    R: Hash + Send + Sync + 'static,
+{
+    let params = params.downcast_ref().unwrap();
+    let result = f(state, params);
+    let fingerprint = o_print(&result);
+    (Box::new(result), fingerprint)
+}
+
+fn get<T, R>(db: &salsa::Db<State>, query_type: salsa::QueryTypeId, param: T) -> (Arc<R>, Vec<salsa::QueryTypeId>)
+where
+    T: Hash + Send + Sync + 'static,
+    R: Send + Sync + 'static,
+{
+    let i_print = i_print(&param);
+    let param = Box::new(param);
+    let (res, trace) = db.get(salsa::QueryId(query_type, i_print), param);
+    (res.downcast().unwrap(), trace)
+}
+
+struct QueryCtx<'a>(&'a salsa::QueryCtx<State>);
+
+impl<'a> QueryCtx<'a> {
+    fn get_text(&self, id: u32) -> Arc<String> {
+        let i_print = i_print(&id);
+        let text = self.0.get(salsa::QueryId(GET_TEXT, i_print), Arc::new(id));
+        text.downcast().unwrap()
+    }
+    fn get_files(&self) -> Arc<Vec<u32>> {
+        let i_print = i_print(&());
+        let files = self.0.get(salsa::QueryId(GET_FILES, i_print), Arc::new(()));
+        let res = files.downcast().unwrap();
+        res
+    }
+    fn get_n_lines(&self, id: u32) -> usize {
+        let i_print = i_print(&id);
+        let n_lines = self.0.get(salsa::QueryId(FILE_NEWLINES, i_print), Arc::new(id));
+        *n_lines.downcast().unwrap()
+    }
+}
+
+fn mk_query<T, R>(
+    query_ctx: &salsa::QueryCtx<State>,
+    params: &(Any + Send + Sync + 'static),
+    f: fn(QueryCtx, &T) -> R,
+) -> (Box<Any + Send + Sync + 'static>, salsa::OutputFingerprint)
+where
+    T: 'static,
+    R: Hash + Send + Sync + 'static,
+{
+    let params: &T = params.downcast_ref().unwrap();
+    let query_ctx = QueryCtx(query_ctx);
+    let result = f(query_ctx, params);
+    let fingerprint = o_print(&result);
+    (Box::new(result), fingerprint)
+}
+
+fn mk_queries() -> salsa::QueryConfig<State> {
+    salsa::QueryConfig::<State>::new()
+        .with_ground_query(GET_TEXT, |state, id| {
+            mk_ground_query::<u32, String>(state, id, |state, id| state[id].clone())
+        })
+        .with_ground_query(GET_FILES, |state, id| {
+            mk_ground_query::<(), Vec<u32>>(state, id, |state, &()| state.keys().cloned().collect())
+        })
+        .with_query(FILE_NEWLINES, |query_ctx, id| {
+            mk_query(query_ctx, id, |query_ctx, &id| {
+                let text = query_ctx.get_text(id);
+                text.lines().count()
+            })
+        })
+        .with_query(TOTAL_NEWLINES, |query_ctx, id| {
+            mk_query(query_ctx, id, |query_ctx, &()| {
+                let mut total = 0;
+                for &id in query_ctx.get_files().iter() {
+                    total += query_ctx.get_n_lines(id)
+                }
+                total
+            })
+        })
+}
+
+#[test]
+fn test_number_of_lines() {
+    let mut state = State::new();
+    let db = salsa::Db::new(mk_queries(), state.clone());
+    let (newlines, trace) = get::<(), usize>(&db, TOTAL_NEWLINES, ());
+    assert_eq!(*newlines, 0);
+    assert_eq!(trace.len(), 2);
+    let (newlines, trace) = get::<(), usize>(&db, TOTAL_NEWLINES, ());
+    assert_eq!(*newlines, 0);
+    assert_eq!(trace.len(), 0);
+
+    state.insert(1, "hello\nworld".to_string());
+    let db = db.with_ground_data(state.clone());
+    let (newlines, trace) = get::<(), usize>(&db, TOTAL_NEWLINES, ());
+    assert_eq!(*newlines, 2);
+    assert_eq!(trace.len(), 4);
+
+    state.insert(2, "spam\neggs".to_string());
+    let db = db.with_ground_data(state.clone());
+    let (newlines, trace) = get::<(), usize>(&db, TOTAL_NEWLINES, ());
+    assert_eq!(*newlines, 4);
+    assert_eq!(trace.len(), 5);
+
+    for i in 0..10 {
+        state.insert(i + 10, "spam".to_string());
+    }
+    let db = db.with_ground_data(state.clone());
+    let (newlines, trace) = get::<(), usize>(&db, TOTAL_NEWLINES, ());
+    assert_eq!(*newlines, 14);
+    assert_eq!(trace.len(), 24);
+
+    state.insert(15, String::new());
+    let db = db.with_ground_data(state.clone());
+    let (newlines, trace) = get::<(), usize>(&db, TOTAL_NEWLINES, ());
+    assert_eq!(*newlines, 13);
+    assert_eq!(trace.len(), 15);
+}
+
+fn o_print<T: Hash>(x: &T) -> salsa::OutputFingerprint {
+    let mut hasher = DefaultHasher::new();
+    x.hash(&mut hasher);
+    let hash = hasher.finish();
+    salsa::OutputFingerprint(hash)
+}
+
+fn i_print<T: Hash>(x: &T) -> salsa::InputFingerprint {
+    let mut hasher = DefaultHasher::new();
+    x.hash(&mut hasher);
+    let hash = hasher.finish();
+    salsa::InputFingerprint(hash)
+}