fix(zod): generated schemas fail to compile when a delegate discrimin ator field has default value (#1705)

Author: ymc9

packages/schema/src/plugins/zod/generator.ts

@@ -370,10 +370,10 @@ export function ${refineFuncName}<T, D extends z.ZodTypeDef>(schema: z.ZodType<T
             }
 
             // delegate discriminator fields are to be excluded from mutation schemas
-            const delegateFields = model.fields.filter((field) => isDiscriminatorField(field));
+            const delegateDiscriminatorFields = model.fields.filter((field) => isDiscriminatorField(field));
             const omitDiscriminators =
-                delegateFields.length > 0
-                    ? `.omit({ ${delegateFields.map((f) => `${f.name}: true`).join(', ')} })`
+                delegateDiscriminatorFields.length > 0
+                    ? `.omit({ ${delegateDiscriminatorFields.map((f) => `${f.name}: true`).join(', ')} })`
                     : '';
 
             ////////////////////////////////////////////////
@@ -485,9 +485,11 @@ export const ${upperCaseFirst(model.name)}PrismaUpdateSchema = ${prismaUpdateSch
 
             // mark fields with default as optional
             if (fieldsWithDefault.length > 0) {
+                // delegate discriminator fields are omitted from the base schema, so we need
+                // to take care not to make them partial otherwise the schema won't compile
                 createSchema = this.makePartial(
                     createSchema,
-                    fieldsWithDefault.map((f) => f.name)
+                    fieldsWithDefault.filter((f) => !delegateDiscriminatorFields.includes(f)).map((f) => f.name)
                 );
             }
 

tests/regression/tests/issue-1693.test.ts

@@ -0,0 +1,20 @@
+import { loadSchema } from '@zenstackhq/testtools';
+
+describe('issue 1693', () => {
+    it('regression', async () => {
+        await loadSchema(
+            `
+            model Animal {
+                id String @id @default(uuid())
+                animalType String @default("")
+                @@delegate(animalType)
+            }
+
+            model Dog extends Animal {
+                name String
+            }
+            `,
+            { fullZod: true }
+        );
+    });
+});