fix(ext/kv): throw on the Kv constructor (#18978)

Closes #18963

---------

Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>

2 files changed, 15 insertions, 2 deletions

diff --git a/cli/tests/unit/kv_test.ts b/cli/tests/unit/kv_test.ts
index 3a3476857..3c5efa588 100644
--- a/cli/tests/unit/kv_test.ts
+++ b/cli/tests/unit/kv_test.ts
@@ -1256,6 +1256,12 @@ dbTest("keys must be arrays", async (db) => {
   );
 });
 
+Deno.test("Deno.Kv constructor throws", () => {
+  assertThrows(() => {
+    new Deno.Kv();
+  });
+});
+
 // This function is never called, it is just used to check that all the types
 // are behaving as expected.
 async function _typeCheckingTests() {
diff --git a/ext/kv/01_db.ts b/ext/kv/01_db.ts
index ca37aa840..f8181cc2e 100644
--- a/ext/kv/01_db.ts
+++ b/ext/kv/01_db.ts
@@ -23,7 +23,7 @@ const encodeCursor: (
 
 async function openKv(path: string) {
   const rid = await core.opAsync("op_kv_database_open", path);
-  return new Kv(rid);
+  return new Kv(rid, kvSymbol);
 }
 
 interface RawKvEntry {
@@ -43,10 +43,17 @@ type RawValue = {
   value: bigint;
 };
 
+const kvSymbol = Symbol("KvRid");
+
 class Kv {
   #rid: number;
 
-  constructor(rid: number) {
+  constructor(rid: number = undefined, symbol: symbol = undefined) {
+    if (kvSymbol !== symbol) {
+      throw new TypeError(
+        "Deno.Kv can not be constructed, use Deno.openKv instead.",
+      );
+    }
     this.#rid = rid;
   }