feat!: upgrade to Zod 4

apps/example-todo-app/package.json

@@ -29,7 +29,7 @@
     "react": "18.2.0",
     "react-dom": "18.2.0",
     "uuid": "^8.3.2",
-    "zod": "^3.17.3"
+    "zod": "^4.3.5"
   },
   "devDependencies": {
     "@types/node": "18.0.1",

apps/example-todo-app/pages/api/todo/get.ts

@@ -20,7 +20,7 @@ export const route_spec = checkRouteSpec({
   queryParams,
   jsonResponse: z.object({
     ok: z.boolean(),
-    todo: ZT.todo,
+    todo: ZT.todo.optional(),
     error: z
       .object({
         type: z.string(),

apps/example-todo-app/pages/api/todo/index.ts

@@ -20,7 +20,7 @@ export const route_spec = checkRouteSpec({
   queryParams,
   jsonResponse: z.object({
     ok: z.boolean(),
-    todo: ZT.todo,
+    todo: ZT.todo.optional(),
     error: z
       .object({
         type: z.string(),

apps/example-todo-app/tests/api/todo/array-query-brackets.test.ts

@@ -20,7 +20,8 @@ test("GET /todo/array-query-brackets (comma-separated array values)", async (t)
     .catch((r) => r)
 
   t.is(status, 400)
-  t.is(error.message, `Expected array, received string for "ids"`)
+  // Zod 4 prefixes with "Invalid input: " so we check for the core message
+  t.true(error.message.includes('expected array, received string for "ids"'))
 })
 
 test("GET /todo/array-query-brackets (bracket array values)", async (t) => {

apps/example-todo-app/tests/api/todo/array-query-repeat.test.ts

@@ -20,7 +20,8 @@ test("GET /todo/array-query-repeat (comma-separated array values)", async (t) =>
     .catch((r) => r)
 
   t.is(status, 400)
-  t.is(error.message, `Expected array, received string for "ids"`)
+  // Zod 4 prefixes with "Invalid input: " so we check for the core message
+  t.true(error.message.includes('expected array, received string for "ids"'))
 })
 
 test("GET /todo/array-query-repeat (bracket array values)", async (t) => {

apps/example-todo-app/tests/api/todo/get-boolean.test.ts

@@ -4,7 +4,7 @@ import axiosAssert from "tests/fixtures/axios-assert"
 import getTestServer from "tests/fixtures/get-test-server"
 import { v4 as uuidv4 } from "uuid"
 
-test.failing("GET /todo/get", async (t) => {
+test("GET /todo/get", async (t) => {
   const { axios } = await getTestServer(t)
 
   axios.defaults.headers.common.Authorization = `Bearer auth_token`

apps/example-todo-app/tests/openapi-generation/openapi-generation.test.ts

@@ -130,28 +130,27 @@ test("generateOpenAPI includes GET even when POST is defined", async (t) => {
   const methods = Object.keys(openapiJson.paths["/api/todo/list"])
   t.is(2, methods.length)
 
-  // GET includes parameters
-  t.deepEqual(
-    {
-      name: "ids",
-      in: "query",
-      required: true,
-      schema: {
-        items: {
-          format: "uuid",
-          type: "string",
-        },
-        type: "array",
+  // GET includes parameters (using t.like for flexibility with Zod 4's extra properties like pattern)
+  t.like(openapiJson.paths["/api/todo/list"].get.parameters[0], {
+    name: "ids",
+    in: "query",
+    required: true,
+    schema: {
+      items: {
+        format: "uuid",
+        type: "string",
       },
+      type: "array",
     },
-    openapiJson.paths["/api/todo/list"].get.parameters[0]
-  )
+  })
 
   t.falsy(openapiJson.paths["/api/todo/list"].get.requestBody)
 
-  // POST route has request body
-
-  t.deepEqual(
+  // POST route has request body (using t.like for flexibility with Zod 4's extra properties)
+  t.like(
+    openapiJson.paths["/api/todo/list"].post.requestBody.content[
+      "application/json"
+    ].schema,
     {
       properties: {
         ids: {
@@ -164,10 +163,7 @@ test("generateOpenAPI includes GET even when POST is defined", async (t) => {
       },
       required: ["ids"],
       type: "object",
-    },
-    openapiJson.paths["/api/todo/list"].post.requestBody.content[
-      "application/json"
-    ].schema
+    }
   )
 
   t.falsy(openapiJson.paths["/api/todo/list"].post.parameters)

packages/nextlove/package.json

@@ -53,19 +53,17 @@
     "react": ">=18",
     "react-dom": ">=18",
     "typescript": "^5.0.2",
-    "zod": "^3.0.0"
+    "zod": "^3.0.0 || ^4.0.0"
   },
   "dependencies": {
     "@types/js-yaml": "^4.0.9",
     "dedent": "^1.5.1",
     "js-yaml": "^4.1.0",
     "lodash": "^4.17.21",
     "openapi3-ts": "^4.4.0",
-    "ts-deepmerge": "^6.0.3",
     "ts-morph": "^21.0.1"
   },
   "devDependencies": {
-    "@anatine/zod-openapi": "^2.0.1",
     "@types/lodash": "^4.14.182",
     "@types/node": "18.0.0",
     "@types/prettier": "^2.7.1",
@@ -91,6 +89,6 @@
     "tsup": "^5.6.3",
     "turbo": "^1.3.1",
     "type-fest": "^3.1.0",
-    "zod": "^3.21.4"
+    "zod": "^4.3.5"
   }
 }

packages/nextlove/src/generators/generate-openapi/index.ts

@@ -14,6 +14,7 @@ import { parseFrontMatter, testFrontMatter } from "../lib/front-matter"
 import dedent from "dedent"
 import { prefixObjectKeysWithX } from "../utils/prefix-object-keys-with-x"
 import { dashifyObjectKeys } from "../utils/dashify-object-keys"
+import { getTypeName } from "../../lib/zod-compat"
 
 function replaceFirstCharToLowercase(str: string) {
   if (str.length === 0) {
@@ -191,9 +192,9 @@ export async function generateOpenAPI(opts: GenerateOpenAPIOpts) {
         body_to_generate_schema = routeSpec.jsonBody ?? routeSpec.commonParams
 
         if (routeSpec.jsonBody && routeSpec.commonParams) {
-          body_to_generate_schema = routeSpec.jsonBody.merge(
-            routeSpec.commonParams
-          )
+          body_to_generate_schema = (
+            routeSpec.jsonBody as z.ZodObject<any>
+          ).merge(routeSpec.commonParams as z.ZodObject<any>)
         }
       } else {
         body_to_generate_schema = routeSpec.jsonBody
@@ -207,9 +208,9 @@ export async function generateOpenAPI(opts: GenerateOpenAPIOpts) {
           routeSpec.queryParams ?? routeSpec.commonParams
 
         if (routeSpec.queryParams && routeSpec.commonParams) {
-          query_to_generate_schema = routeSpec.queryParams.merge(
-            routeSpec.commonParams
-          )
+          query_to_generate_schema = (
+            routeSpec.queryParams as z.ZodObject<any>
+          ).merge(routeSpec.commonParams as z.ZodObject<any>)
         }
       }
 
@@ -271,11 +272,8 @@ export async function generateOpenAPI(opts: GenerateOpenAPIOpts) {
       const { addOkStatus = true } = setupParams
 
       if (jsonResponse) {
-        if (
-          !jsonResponse._def ||
-          !jsonResponse._def.typeName ||
-          jsonResponse._def.typeName !== "ZodObject"
-        ) {
+        const jsonResponseTypeName = getTypeName(jsonResponse)
+        if (jsonResponseTypeName !== "ZodObject") {
           console.warn(
             chalk.yellow(
               `Skipping route ${routePath} because the response is not a ZodObject.`

packages/nextlove/src/generators/generate-route-types/index.ts

@@ -2,7 +2,13 @@ import * as fs from "node:fs/promises"
 import { parseRoutesInPackage } from "../lib/parse-routes-in-package"
 import { zodToTs, printNode } from "../lib/zod-to-ts"
 import prettier from "prettier"
-import { z, ZodEffects, ZodOptional } from "zod"
+import { z, ZodTypeAny } from "zod"
+import {
+  getTypeName,
+  getEffectsSchema,
+  getInnerType,
+  getShape,
+} from "../../lib/zod-compat"
 
 interface GenerateRouteTypesOpts {
   packageDir: string
@@ -35,24 +41,37 @@ export const generateRouteTypes = async (opts: GenerateRouteTypesOpts) => {
   const routeDefs: string[] = []
   for (const [_, { route, routeSpec, setupParams }] of filteredRoutes) {
     const maxDuration = routeSpec.maxDuration ?? setupParams.maxDuration
-    const queryKeys = Object.keys(routeSpec.queryParams?.shape ?? {})
+    const queryKeys = Object.keys(
+      routeSpec.queryParams ? getShape(routeSpec.queryParams) ?? {} : {}
+    )
     const pathParameters = queryKeys.filter((key) => route.includes(`[${key}]`))
 
     // queryParams might be a ZodEffects or ZodOptional in some cases
-    let queryParams = routeSpec.queryParams
-    while (
-      queryParams &&
-      ("sourceType" in queryParams || "unwrap" in queryParams)
-    ) {
-      if ("sourceType" in queryParams) {
-        queryParams = (queryParams as unknown as ZodEffects<any>).sourceType()
-      } else if ("unwrap" in queryParams) {
-        queryParams = (queryParams as unknown as ZodOptional<any>).unwrap()
+    let queryParams: ZodTypeAny | undefined = routeSpec.queryParams
+    while (queryParams) {
+      const typeName = getTypeName(queryParams)
+      if (typeName === "ZodEffects") {
+        const inner = getEffectsSchema(queryParams)
+        if (inner) {
+          queryParams = inner
+          continue
+        }
+      } else if (typeName === "ZodOptional") {
+        const inner = getInnerType(queryParams)
+        if (inner) {
+          queryParams = inner
+          continue
+        }
       }
+      break
     }
 
-    if (queryParams && "omit" in queryParams) {
-      queryParams = queryParams.omit(
+    if (
+      queryParams &&
+      "omit" in queryParams &&
+      typeof (queryParams as any).omit === "function"
+    ) {
+      queryParams = (queryParams as any).omit(
         Object.fromEntries(pathParameters.map((param) => [param, true]))
       )
     }