fix: middleware inheritance for base-pathed root (/) routes (#319)

* Initial plan

* fix middleware for base-pathed root route

* style: normalize middleware callback spacing in regression test

* test: strengthen base-path root middleware regression

* test: restore CORS root middleware regression case

---------

Author: Copilot

__tests__/basePath.unit.js

@@ -58,4 +58,49 @@ describe('Base Path Tests:', function() {
     expect(result).toEqual({ multiValueHeaders: { 'content-type': ['application/json'] }, statusCode: 200, body: '{"path":"/v1/test/test2/test3","method":"get","status":"ok"}', isBase64Encoded: false })
   }) // end it
 
+  it('Middleware stack is inherited for root path when basepathed', async function() {
+    const testApi = require('../index')({ base: 'base-path' })
+    testApi.use((req, res, next) => {
+      req.middlewareState = {
+        segments: req.path.split('/').filter(Boolean)
+      }
+      next()
+    })
+    testApi.use((req, res, next) => {
+      req.middlewareState.trace = req.middlewareState.segments.join(':')
+      res.header('x-middleware-trace', req.middlewareState.trace)
+      next()
+    })
+    testApi.get('/', async req => ({
+      status: 'ok',
+      trace: req.middlewareState.trace,
+      segmentCount: req.middlewareState.segments.length
+    }))
+
+    let _event = Object.assign({},event,{ path: '/base-path/' })
+    let result = await new Promise(r => testApi.run(_event,{},(e,res) => { r(res) }))
+    expect(result).toEqual({
+      multiValueHeaders: {
+        'content-type': ['application/json'],
+        'x-middleware-trace': ['base-path']
+      },
+      statusCode: 200,
+      body: '{"status":"ok","trace":"base-path","segmentCount":1}',
+      isBase64Encoded: false
+    })
+  }) // end it
+
+  it('Middleware runs for root path when basepathed (CORS regression)', async function() {
+    const testApi = require('../index')({ base: 'base-path' })
+    testApi.use((req, res, next) => {
+      res.cors()
+      next()
+    })
+    testApi.get('/', async () => ({ status: 'ok' }))
+
+    let _event = Object.assign({},event,{ path: '/base-path/' })
+    let result = await new Promise(r => testApi.run(_event,{},(e,res) => { r(res) }))
+    expect(result.multiValueHeaders).toHaveProperty('access-control-allow-origin')
+  }) // end it
+
 }) // end BASEPATH tests

index.js

@@ -207,6 +207,19 @@ class API {
                 routes['ROUTES'][route[i]]['MIDDLEWARE'].stack;
             } // end if
 
+            // Check for a wildcard child middleware (e.g. base path + '/')
+            if (
+              parsedPath.length === 0 &&
+              route[i] !== '*' &&
+              routes['ROUTES'][route[i]] &&
+              routes['ROUTES'][route[i]]['ROUTES'] &&
+              routes['ROUTES'][route[i]]['ROUTES']['*'] &&
+              routes['ROUTES'][route[i]]['ROUTES']['*']['MIDDLEWARE']
+            ) {
+              _stack['*'][method] =
+                routes['ROUTES'][route[i]]['ROUTES']['*']['MIDDLEWARE'].stack;
+            } // end if
+
             // Generate the route/method meta data
             let meta = {
               vars: pathVars,