From 932bb4f58b1235707db90e40f8903f0e4dc9e34a Mon Sep 17 00:00:00 2001
From: Sayan Nandan <nandansayan@outlook.com>
Date: Wed, 1 Feb 2023 09:00:54 -0800
Subject: [PATCH] Fix remove len impl, use relaxed and add tests

---
 server/src/engine/idx/mtchm/mod.rs   | 10 +++++--
 server/src/engine/idx/mtchm/tests.rs | 44 ++++++++++++++++++++--------
 2 files changed, 39 insertions(+), 15 deletions(-)

diff --git a/server/src/engine/idx/mtchm/mod.rs b/server/src/engine/idx/mtchm/mod.rs
index 7c20a729..4603189d 100644
--- a/server/src/engine/idx/mtchm/mod.rs
+++ b/server/src/engine/idx/mtchm/mod.rs
@@ -503,6 +503,7 @@ impl<T: TreeElement, C: Config> Tree<T, C> {
                         Self::read_data(node)
                     };
                     let mut ret = W::nx();
+                    let mut rem = false;
                     // this node shouldn't be empty
                     debug_assert!(!data.is_empty(), "logic,empty node not collected");
                     // build new lnode
@@ -511,6 +512,7 @@ impl<T: TreeElement, C: Config> Tree<T, C> {
                         .filter_map(|this_elem| {
                             if this_elem.key().borrow() == k {
                                 ret = W::ex(this_elem);
+                                rem = true;
                                 None
                             } else {
                                 Some(this_elem.clone())
@@ -567,6 +569,7 @@ impl<T: TreeElement, C: Config> Tree<T, C> {
                             break;
                         }
                     }
+                    self.decr_len_by(rem as _);
                     gc(g);
                     return ret;
                 }
@@ -586,10 +589,13 @@ impl<T: TreeElement, C: Config> Tree<T, C> {
 impl<T, C: Config> Tree<T, C> {
     // hilarious enough but true, l doesn't affect safety but only creates an incorrect state
     fn decr_len(&self) {
-        self.l.fetch_sub(1, ORD_ACQ);
+        self.decr_len_by(1)
+    }
+    fn decr_len_by(&self, by: usize) {
+        self.l.fetch_sub(by, ORD_RLX);
     }
     fn incr_len(&self) {
-        self.l.fetch_add(1, ORD_ACQ);
+        self.l.fetch_add(1, ORD_RLX);
     }
     #[inline(always)]
     fn new_lnode(node: LNode<T>) -> Owned<Node<C>> {
diff --git a/server/src/engine/idx/mtchm/tests.rs b/server/src/engine/idx/mtchm/tests.rs
index fe4e5778..43ec8be3 100644
--- a/server/src/engine/idx/mtchm/tests.rs
+++ b/server/src/engine/idx/mtchm/tests.rs
@@ -201,7 +201,7 @@ fn tjoin_all<T>(handles: Vec<JoinHandle<T>>) -> Box<[T]> {
         .collect()
 }
 
-fn store_and_verify_integrity<K, V>(
+fn modify_and_verify_integrity<K, V>(
     token: &ControlToken,
     tree: &Arc<ChmCopy<K, V>>,
     source_buf: &[StringTup],
@@ -230,7 +230,7 @@ fn _action_put(
     let _token = token.acquire_permit();
     let g = cpin();
     data.into_iter().for_each(|(k, v)| {
-        assert!(idx.insert((k, v), &g));
+        assert!(idx.mt_insert(k, v, &g));
     });
 }
 fn _verify_eq(
@@ -255,7 +255,7 @@ fn multispam_insert() {
     let token = ControlToken::new();
     let mut data = Vec::new();
     prepare_data(&mut data, TUP_INCR);
-    store_and_verify_integrity(&token, &idx, &data, _action_put, _verify_eq);
+    modify_and_verify_integrity(&token, &idx, &data, _action_put, _verify_eq);
 }
 
 #[test]
@@ -264,21 +264,13 @@ fn multispam_update() {
     let token = ControlToken::new();
     let mut data = Vec::new();
     prepare_data(&mut data, TUP_INCR);
-    assert!(data
-        .iter()
-        .enumerate()
-        .all(|(i, (k, v))| { i == k.parse().unwrap() && i + 1 == v.parse().unwrap() }));
-    store_and_verify_integrity(&token, &idx, &data, _action_put, _verify_eq);
+    modify_and_verify_integrity(&token, &idx, &data, _action_put, _verify_eq);
     // update our data set
     data.iter_mut().enumerate().for_each(|(i, (_, v))| {
         *v = Arc::new((i + 2).to_string());
     });
-    assert!(data
-        .iter()
-        .enumerate()
-        .all(|(i, (k, v))| { i == k.parse().unwrap() && i + 2 == v.parse().unwrap() }));
     // store and verify integrity
-    store_and_verify_integrity(
+    modify_and_verify_integrity(
         &token,
         &idx,
         &data,
@@ -307,3 +299,29 @@ fn multispam_update() {
         },
     );
 }
+
+#[test]
+fn multispam_delete() {
+    let idx = Arc::default();
+    let token = ControlToken::new();
+    let mut data = Vec::new();
+    prepare_data(&mut data, TUP_INCR);
+    modify_and_verify_integrity(&token, &idx, &data, _action_put, _verify_eq);
+    // now expunge
+    modify_and_verify_integrity(
+        &token,
+        &idx,
+        &data,
+        |tok, idx, chunk| {
+            let g = cpin();
+            let _permit = tok.acquire_permit();
+            chunk.into_iter().for_each(|(k, v)| {
+                assert_eq!(idx.mt_delete_return(&k, &g).unwrap().as_str(), v.as_str());
+            });
+        },
+        |g, idx, orig| {
+            assert!(orig.into_iter().all(|(k, _)| idx.mt_get(k, &g).is_none()));
+            assert!(idx.is_empty(), "expected empty, found {} elements instead", idx.len());
+        },
+    );
+}