fix: findFirst args validation issues

packages/runtime/src/client/crud/operations/find.ts

@@ -7,23 +7,26 @@ export class FindOperationHandler<Schema extends SchemaDef> extends BaseOperatio
         // normalize args to strip `undefined` fields
         const normalizedArgs = this.normalizeArgs(args);
 
+        const findOne = operation === 'findFirst' || operation === 'findUnique';
+
         // parse args
-        const parsedArgs = (validateArgs
-            ? this.inputValidator.validateFindArgs(this.model, operation === 'findUnique', normalizedArgs)
-            : normalizedArgs) as FindArgs<Schema, GetModels<Schema>, true>;
+        let parsedArgs = validateArgs
+            ? this.inputValidator.validateFindArgs(this.model, normalizedArgs, {
+                  unique: operation === 'findUnique',
+                  findOne,
+              })
+            : (normalizedArgs as FindArgs<Schema, GetModels<Schema>, true> | undefined);
 
-        if (operation === 'findFirst') {
+        if (findOne) {
+            // ensure "limit 1"
+            parsedArgs = parsedArgs ?? {};
             parsedArgs.take = 1;
         }
 
         // run query
-        const result = await this.read(
-            this.client.$qb,
-            this.model,
-            parsedArgs,
-        );
+        const result = await this.read(this.client.$qb, this.model, parsedArgs);
 
-        const finalResult = operation === 'findMany' ? result : (result[0] ?? null);
+        const finalResult = findOne ? (result[0] ?? null) : result;
         return finalResult;
     }
 }

packages/runtime/src/client/crud/validator.ts

@@ -40,14 +40,11 @@ export class InputValidator<Schema extends SchemaDef> {
 
     constructor(private readonly schema: Schema) {}
 
-    validateFindArgs(model: GetModels<Schema>, unique: boolean, args: unknown) {
-        return this.validate<FindArgs<Schema, GetModels<Schema>, true>, Parameters<typeof this.makeFindSchema>[1]>(
-            model,
-            'find',
-            { unique },
-            (model, options) => this.makeFindSchema(model, options),
-            args,
-        );
+    validateFindArgs(model: GetModels<Schema>, args: unknown, options: { unique: boolean; findOne: boolean }) {
+        return this.validate<
+            FindArgs<Schema, GetModels<Schema>, true> | undefined,
+            Parameters<typeof this.makeFindSchema>[1]
+        >(model, 'find', options, (model, options) => this.makeFindSchema(model, options), args);
     }
 
     validateCreateArgs(model: GetModels<Schema>, args: unknown) {
@@ -196,7 +193,7 @@ export class InputValidator<Schema extends SchemaDef> {
 
     // #region Find
 
-    private makeFindSchema(model: string, options: { unique: boolean }) {
+    private makeFindSchema(model: string, options: { unique: boolean; findOne: boolean }) {
         const fields: Record<string, z.ZodSchema> = {};
         const where = this.makeWhereSchema(model, options.unique);
         if (options.unique) {
@@ -211,7 +208,11 @@ export class InputValidator<Schema extends SchemaDef> {
 
         if (!options.unique) {
             fields['skip'] = this.makeSkipSchema().optional();
-            fields['take'] = this.makeTakeSchema().optional();
+            if (options.findOne) {
+                fields['take'] = z.literal(1).optional();
+            } else {
+                fields['take'] = this.makeTakeSchema().optional();
+            }
             fields['orderBy'] = this.orArray(this.makeOrderBySchema(model, true, false), true).optional();
             fields['cursor'] = this.makeCursorSchema(model).optional();
             fields['distinct'] = this.makeDistinctSchema(model).optional();

packages/runtime/test/client-api/computed-fields.test.ts

@@ -75,7 +75,7 @@ model User {
             await expect(
                 db.user.findFirst({
                     orderBy: { upperName: 'desc' },
-                    take: -1,
+                    take: 1,
                 }),
             ).resolves.toMatchObject({
                 upperName: 'ALEX',

packages/runtime/test/client-api/find.test.ts

@@ -1,6 +1,6 @@
 import { afterEach, beforeEach, describe, expect, it } from 'vitest';
 import type { ClientContract } from '../../src/client';
-import { NotFoundError } from '../../src/client/errors';
+import { InputValidationError, NotFoundError } from '../../src/client/errors';
 import { schema } from '../schemas/basic';
 import { createClientSpecs } from './client-specs';
 import { createPosts, createUser } from './utils';
@@ -54,6 +54,10 @@ describe.each(createClientSpecs(PG_DB_NAME))('Client find tests for $provider',
         await expect(client.user.findMany({ take: 2 })).resolves.toHaveLength(2);
         await expect(client.user.findMany({ take: 4 })).resolves.toHaveLength(3);
 
+        // findFirst's take must be 1
+        await expect(client.user.findFirst({ take: 2 })).rejects.toThrow(InputValidationError);
+        await expect(client.user.findFirst({ take: 1 })).toResolveTruthy();
+
         // skip
         await expect(client.user.findMany({ skip: 1 })).resolves.toHaveLength(2);
         await expect(client.user.findMany({ skip: 2 })).resolves.toHaveLength(1);