fix to conversion + test

.changeset/fuzzy-seas-reply.md

@@ -0,0 +1,5 @@
+---
+'@electric-sql/pglite': patch
+---
+
+Fix convert_to

packages/pglite/tests/basic.test.ts

@@ -932,5 +932,33 @@ await testEsmCjsAndDTC(async (importType) => {
         rowCount: 1,
       })
     })
+    it('serialize with no concrete type', async () => {
+      const res0 = await db.exec(`SELECT 1`)
+
+      const res1 = await db.exec(`SELECT convert_to('abc', 'LATIN1')`)
+
+      expect(res1).toEqual([
+        {
+          rows: [
+            {
+              convert_to: new Uint8Array([97, 98, 99]),
+            },
+          ],
+          fields: [
+            {
+              name: 'convert_to',
+              dataTypeID: 17,
+            },
+          ],
+          command: 'SELECT',
+          affectedRows: 0,
+          rowCount: 1,
+        },
+      ])
+
+      const res2 = await db.exec(`SELECT 1`)
+
+      expect(res2).toEqual(res0)
+    })
   })
 })