fix: preserve transaction state in $use, $unuse, and $unuseAll

When calling $use(), $unuse(), or $unuseAll() on a transaction client,
the returned client would escape the active transaction because the
constructor always creates a fresh Kysely instance from kyselyProps.

Propagate the transaction Kysely instance to the new client when the
current client is inside a transaction.

Fixes #2494

Author: pkudinov

packages/orm/src/client/client-impl.ts

@@ -378,6 +378,10 @@ export class ClientImpl {
         newClient.inputValidator = new InputValidator(newClient as any, {
             enabled: newOptions.validateInput !== false,
         });
+        // preserve transaction state so the new client stays in the same transaction
+        if (this.kysely.isTransaction) {
+            newClient.kysely = this.kysely;
+        }
         return newClient;
     }
 
@@ -399,6 +403,10 @@ export class ClientImpl {
         newClient.inputValidator = new InputValidator(newClient as any, {
             enabled: newClient.$options.validateInput !== false,
         });
+        // preserve transaction state so the new client stays in the same transaction
+        if (this.kysely.isTransaction) {
+            newClient.kysely = this.kysely;
+        }
         return newClient;
     }
 
@@ -414,6 +422,10 @@ export class ClientImpl {
         newClient.inputValidator = new InputValidator(newClient as any, {
             enabled: newOptions.validateInput !== false,
         });
+        // preserve transaction state so the new client stays in the same transaction
+        if (this.kysely.isTransaction) {
+            newClient.kysely = this.kysely;
+        }
         return newClient;
     }
 

tests/e2e/orm/client-api/transaction.test.ts

@@ -101,6 +101,45 @@ describe('Client raw query tests', () => {
 
             await expect(client.user.findMany()).toResolveWithLength(0);
         });
+
+        it('$unuseAll preserves transaction isolation', async () => {
+            await expect(
+                client.$transaction(async (tx) => {
+                    await tx.$unuseAll().user.create({
+                        data: { email: 'u1@test.com' },
+                    });
+                    throw new Error('rollback');
+                }),
+            ).rejects.toThrow('rollback');
+
+            await expect(client.user.findMany()).toResolveWithLength(0);
+        });
+
+        it('$unuse preserves transaction isolation', async () => {
+            await expect(
+                client.$transaction(async (tx) => {
+                    await tx.$unuse('nonexistent').user.create({
+                        data: { email: 'u1@test.com' },
+                    });
+                    throw new Error('rollback');
+                }),
+            ).rejects.toThrow('rollback');
+
+            await expect(client.user.findMany()).toResolveWithLength(0);
+        });
+
+        it('$use preserves transaction isolation', async () => {
+            await expect(
+                client.$transaction(async (tx) => {
+                    await (tx as any).$use({ id: 'noop', handle: (_node: any, proceed: any) => proceed(_node) }).user.create({
+                        data: { email: 'u1@test.com' },
+                    });
+                    throw new Error('rollback');
+                }),
+            ).rejects.toThrow('rollback');
+
+            await expect(client.user.findMany()).toResolveWithLength(0);
+        });
     });
 
     describe('sequential transaction', () => {