fix(middleware/combine): prevent c.req.routeIndex from being changed (#3663)

* test(middleware/combine): add test for every middleware

Co-authored-by: Paweł Dąbrowski <dabrowskip9@gmail.com>

* refactor(compose): Loosen `compose` parameter types

The current implementation of `compose` does not use some elements of the received middleware,
so they do not have to be passed on.

* fix(middleware/combine): prevent `c.req.routeIndex` from being changed

---------

Co-authored-by: Paweł Dąbrowski <dabrowskip9@gmail.com>

src/compose.ts

@@ -1,5 +1,4 @@
 import { Context } from './context'
-import type { ParamIndexMap, Params } from './router'
 import type { Env, ErrorHandler, NotFoundHandler } from './types'
 
 /**
@@ -31,7 +30,7 @@ interface ComposeContext {
  * @returns {(context: C, next?: Function) => Promise<C>} - A composed middleware function.
  */
 export const compose = <C extends ComposeContext, E extends Env = Env>(
-  middleware: [[Function, unknown], ParamIndexMap | Params][],
+  middleware: [[Function, unknown], unknown][] | [[Function]][],
   onError?: ErrorHandler<E>,
   onNotFound?: NotFoundHandler<E>
 ): ((context: C, next?: Function) => Promise<C>) => {

src/middleware/combine/index.test.ts

@@ -166,6 +166,22 @@ describe('every', () => {
     expect(await res.text()).toBe('Hello Middleware 1')
     expect(middleware2).not.toBeCalled()
   })
+
+  it('Should pass the path params to middlewares', async () => {
+    const app = new Hono()
+    app.use('*', nextMiddleware)
+    const paramMiddleware: MiddlewareHandler = async (c) => {
+      return c.json(c.req.param(), 200)
+    }
+
+    app.use('/:id', every(paramMiddleware))
+    app.get('/:id', (c) => {
+      return c.text('Hello World')
+    })
+
+    const res = await app.request('http://localhost/123')
+    expect(await res.json()).toEqual({ id: '123' })
+  })
 })
 
 describe('except', () => {

src/middleware/combine/index.ts

@@ -89,19 +89,22 @@ export const some = (...middleware: (MiddlewareHandler | Condition)[]): Middlewa
  * ```
  */
 export const every = (...middleware: (MiddlewareHandler | Condition)[]): MiddlewareHandler => {
-  const wrappedMiddleware = middleware.map((m) => async (c: Context, next: Next) => {
+  return async function every(c, next) {
+    const currentRouteIndex = c.req.routeIndex
+    await compose<Context>(
+      middleware.map((m) => [
+        [
+          async (c: Context, next: Next) => {
+            c.req.routeIndex = currentRouteIndex // should be unchanged in this context
             const res = await m(c, next)
             if (res === false) {
               throw new Error('Unmet condition')
             }
             return res
-  })
-
-  const handler = async (c: Context, next: Next) =>
-    compose<Context>(wrappedMiddleware.map((m) => [[m, undefined], c.req.param()]))(c, next)
-
-  return async function every(c, next) {
-    await handler(c, next)
+          },
+        ],
+      ])
+    )(c, next)
   }
 }