fix(policy): handle DefaultInsertValueNode in createManyAndReturn

When rows have asymmetric optional fields, Kysely pads missing columns
with DefaultInsertValueNode. Treat it as null in the policy handler.

Fixes #2460

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: pkudinov

packages/plugins/policy/src/policy-handler.ts

@@ -920,6 +920,10 @@ export class PolicyHandler<Schema extends SchemaDef> extends OperationNodeTransf
         for (let i = 0; i < data.length; i++) {
             const item = data[i]!;
             if (typeof item === 'object' && item && 'kind' in item) {
+                if (item.kind === 'DefaultInsertValueNode') {
+                    result.push({ node: ValueNode.create(null), raw: null });
+                    continue;
+                }
                 const fieldDef = QueryUtils.requireField(this.client.$schema, model, fields[i]!);
                 invariant(item.kind === 'ValueNode', 'expecting a ValueNode');
                 result.push({

tests/regression/test/issue-2460.test.ts

@@ -7,10 +7,10 @@ describe('Regression for issue #2460', () => {
     it('createManyAndReturn with asymmetric optional fields across rows', async () => {
         const db = await createPolicyTestClient(
             `
-type AuthUser {
-    id   String
+model User {
+    id   Int    @id @default(autoincrement())
     role String
-    @@auth
+    @@allow('all', true)
 }
 
 model Item {
@@ -20,13 +20,12 @@ model Item {
     @@allow('all', auth().role == 'admin')
 }
             `,
-            {
-                provider: 'postgresql',
-                auth: { id: '1', role: 'admin' },
-            },
+            { provider: 'postgresql' },
         );
 
-        const result = await db.item.createManyAndReturn({
+        const user = await db.user.create({ data: { role: 'admin' } });
+
+        const result = await db.$setAuth(user).item.createManyAndReturn({
             data: [
                 { key: 'a', note: 'hello' },
                 { key: 'b' },