fix(runtime): throw PrismaValidationError when auth() is used in @default without user context

packages/runtime/src/enhancements/default-auth.ts

@@ -1,12 +1,19 @@
 /* eslint-disable @typescript-eslint/no-unused-vars */
 /* eslint-disable @typescript-eslint/no-explicit-any */
 
-import { FieldInfo, NestedWriteVisitor, PrismaWriteActionType, enumerate, getFields, requireField } from '../cross';
-import { clone } from '../cross';
+import {
+    FieldInfo,
+    NestedWriteVisitor,
+    PrismaWriteActionType,
+    clone,
+    enumerate,
+    getFields,
+    requireField,
+} from '../cross';
 import { DbClientContract } from '../types';
 import { EnhancementContext, InternalEnhancementOptions } from './create-enhancement';
 import { DefaultPrismaProxyHandler, PrismaProxyActions, makeProxy } from './proxy';
-import { isUnsafeMutate } from './utils';
+import { isUnsafeMutate, prismaClientValidationError } from './utils';
 
 /**
  * Gets an enhanced Prisma client that supports `@default(auth())` attribute.
@@ -143,7 +150,11 @@ class DefaultAuthHandler extends DefaultPrismaProxyHandler {
 
     private getDefaultValueFromAuth(fieldInfo: FieldInfo) {
         if (!this.userContext) {
-            throw new Error(`Evaluating default value of field \`${fieldInfo.name}\` requires a user context`);
+            throw prismaClientValidationError(
+                this.prisma,
+                this.options.prismaModule,
+                `Evaluating default value of field \`${fieldInfo.name}\` requires a user context`
+            );
         }
         return fieldInfo.defaultValueProvider?.(this.userContext);
     }

tests/regression/tests/issue-1596.test.ts

@@ -0,0 +1,34 @@
+import { isPrismaClientValidationError } from '@zenstackhq/runtime';
+import { loadSchema } from '@zenstackhq/testtools';
+
+describe('issue 1596', () => {
+    it('regression', async () => {
+        const { enhance } = await loadSchema(
+            `
+            model User {
+                id Int @id
+                posts Post[]
+            }
+
+            model Post {
+                id Int @id
+                title String
+                author User @relation(fields: [authorId], references: [id])
+                authorId Int @default(auth().id)
+            }
+            `
+        );
+
+        const db = enhance();
+
+        try {
+            await db.post.create({ data: { title: 'Post1' } });
+        } catch (e) {
+            // eslint-disable-next-line jest/no-conditional-expect
+            expect(isPrismaClientValidationError(e)).toBe(true);
+            return;
+        }
+
+        throw new Error('Expected error');
+    });
+});