don't update cache if scan is key_only (#346)

* don't update cache if scan is key_only

Signed-off-by: ekexium <ekexium@gmail.com>

* fix clippy

Signed-off-by: ekexium <ekexium@gmail.com>

Author: ekexium

src/transaction/buffer.rs

@@ -110,6 +110,7 @@ impl Buffer {
         &mut self,
         range: BoundRange,
         limit: u32,
+        update_cache: bool,
         f: F,
     ) -> Result<impl Iterator<Item = KvPair>>
     where
@@ -147,8 +148,10 @@ impl Buffer {
         }
 
         // update local buffer
-        for (k, v) in &results {
-            self.update_cache(k.clone(), Some(v.clone()));
+        if update_cache {
+            for (k, v) in &results {
+                self.update_cache(k.clone(), Some(v.clone()));
+            }
         }
 
         let mut res = results

src/transaction/transaction.rs

@@ -690,6 +690,7 @@ impl<PdC: PdClient> Transaction<PdC> {
             .scan_and_fetch(
                 range.into(),
                 limit,
+                !key_only,
                 move |new_range, new_limit| async move {
                     let request = new_scan_request(new_range, timestamp, new_limit, key_only);
                     let plan = PlanBuilder::new(rpc, request)

tests/integration_tests.rs

@@ -395,7 +395,7 @@ async fn raw_req() -> Result<()> {
     assert_eq!(res[1].1, "v2".as_bytes());
 
     // k1,k2; batch_put then batch_get
-    let _ = client
+    client
         .batch_put(vec![
             ("k3".to_owned(), "v3".to_owned()),
             ("k4".to_owned(), "v4".to_owned()),
@@ -437,7 +437,7 @@ async fn raw_req() -> Result<()> {
     assert_eq!(res.len(), 0);
 
     // empty; batch_put then scan
-    let _ = client
+    client
         .batch_put(vec![
             ("k3".to_owned(), "v3".to_owned()),
             ("k5".to_owned(), "v5".to_owned()),
@@ -860,6 +860,29 @@ async fn raw_cas() -> Result<()> {
     Ok(())
 }
 
+#[tokio::test]
+#[serial]
+async fn txn_scan() -> Result<()> {
+    init().await?;
+    let client = TransactionClient::new_with_config(pd_addrs(), Default::default(), None).await?;
+
+    let k1 = b"a".to_vec();
+    let v = b"b".to_vec();
+
+    // pessimistic
+    let option = TransactionOptions::new_pessimistic().drop_check(tikv_client::CheckLevel::Warn);
+    let mut t = client.begin_with_options(option.clone()).await?;
+    t.put(k1.clone(), v).await?;
+    t.commit().await?;
+
+    let mut t2 = client.begin_with_options(option).await?;
+    t2.get(k1.clone()).await?;
+    t2.key_exists(k1).await?;
+    t2.commit().await?;
+
+    Ok(())
+}
+
 // helper function
 async fn get_u32(client: &RawClient, key: Vec<u8>) -> Result<u32> {
     let x = client.get(key).await?.unwrap();

tests/mock_tikv_tests.rs

@@ -24,8 +24,8 @@ mod test {
         assert_eq!(res.unwrap(), None);
 
         // empty; put then batch_get
-        let _ = client.put("k1".to_owned(), "v1".to_owned()).await.unwrap();
-        let _ = client.put("k2".to_owned(), "v2".to_owned()).await.unwrap();
+        client.put("k1".to_owned(), "v1".to_owned()).await.unwrap();
+        client.put("k2".to_owned(), "v2".to_owned()).await.unwrap();
 
         let res = client
             .batch_get(vec!["k1".to_owned(), "k2".to_owned(), "k3".to_owned()])
@@ -36,7 +36,7 @@ mod test {
         assert_eq!(res[1].1, "v2".as_bytes());
 
         // k1,k2; batch_put then batch_get
-        let _ = client
+        client
             .batch_put(vec![
                 KvPair::new("k3".to_owned(), "v3".to_owned()),
                 KvPair::new("k4".to_owned(), "v4".to_owned()),