insert_via_serialize_bsatn: fix nested mut borrow bug

clockworklabs · Jan 2, 2025 · 2ed6ef4 · 2ed6ef4
1 parent 5df4fc2
commit 2ed6ef4
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Showing 3 changed files with 8 additions and 3 deletions.
diff --git a/crates/core/src/db/datastore/locking_tx_datastore/mod.rs b/crates/core/src/db/datastore/locking_tx_datastore/mod.rs
@@ -1,4 +1,4 @@
-#![forbid(unsafe_op_in_unsafe_fn)]
+#![deny(unsafe_op_in_unsafe_fn)]
 
 pub mod committed_state;
 pub mod datastore;

diff --git a/crates/core/src/db/datastore/locking_tx_datastore/mut_tx.rs b/crates/core/src/db/datastore/locking_tx_datastore/mut_tx.rs
@@ -23,6 +23,7 @@ use crate::{
     error::{IndexError, SequenceError, TableError},
     execution_context::ExecutionContext,
 };
+use core::cell::RefCell;
 use core::ops::RangeBounds;
 use core::{iter, ops::Bound};
 use smallvec::SmallVec;
@@ -1165,7 +1166,11 @@ impl MutTxId {
         table_id: TableId,
         row: &T,
     ) -> Result<(ColList, RowRefInsertion<'a>)> {
-        with_sys_table_buf(|buf| {
+        thread_local! {
+            static BUF: RefCell<Vec<u8>> = const { RefCell::new(Vec::new()) };
+        }
+        BUF.with_borrow_mut(|buf| {
+            buf.clear();
             to_writer(buf, row).unwrap();
             self.insert::<true>(table_id, buf)
         })

diff --git a/crates/core/src/db/datastore/system_tables.rs b/crates/core/src/db/datastore/system_tables.rs
@@ -1312,7 +1312,7 @@ pub(crate) fn with_sys_table_buf<R>(run: impl FnOnce(&mut Vec<u8>) -> R) -> R {
     })
 }
 
-/// Read a value from a system table via BSatn.
+/// Read a value from a system table via BSATN.
 fn read_via_bsatn<T: DeserializeOwned>(row: RowRef<'_>) -> Result<T, DBError> {
     with_sys_table_buf(|buf| Ok(row.read_via_bsatn::<T>(buf)?))
 }