feat(sql): truncate WAL on stop_io()

src/context.rs

@@ -423,6 +423,9 @@ impl Context {
     /// Stops the IO scheduler.
     pub async fn stop_io(&self) {
         self.scheduler.stop(self).await;
+        if let Err(err) = self.sql.checkpoint(self).await {
+            error!(self, "Failed to checkpoint the database: {err:#}.");
+        }
     }
 
     /// Restarts the IO scheduler if it was running before

src/sql.rs

@@ -131,6 +131,23 @@ impl Sql {
         // drop closes the connection
     }
 
+    /// Flushes the WAL file.
+    pub(crate) async fn checkpoint(&self, context: &Context) -> Result<()> {
+        let busy = self
+            .call_write(move |conn| {
+                let busy = conn.query_row("PRAGMA wal_checkpoint(TRUNCATE)", (), |row| {
+                    let busy: bool = row.get(0)?;
+                    Ok(busy)
+                })?;
+                Ok(busy)
+            })
+            .await?;
+        if busy {
+            warn!(context, "Failed to checkpoint WAL");
+        }
+        Ok(())
+    }
+
     /// Imports the database from a separate file with the given passphrase.
     pub(crate) async fn import(&self, path: &Path, passphrase: String) -> Result<()> {
         let path_str = path