fix: #282 Custom error handler not being reached

.github/workflows/build.yml

@@ -12,7 +12,7 @@ jobs:
 
     strategy:
       matrix:
-        node: ['10', '12', '14', '15']
+        node: ['10', '12', '14', '16', '18']
 
     name: Node ${{ matrix.node }} testing
 

demos/error/index.js

@@ -26,4 +26,4 @@ app.use((error, req, res, next) => {
   res.send('test.', 500);
 });
 
-app.listen(4000, () => console.log('Server is listening on port 3000...'));
+app.listen(3000, () => console.log('Server is listening on port 3000...'));

lib/router.js

@@ -106,9 +106,12 @@ class Router {
       const router = routers[i];
 
       for (let j = 0; j < router.routes.length; j += 1) {
-        const { path: childPath, middlewarePath, fns, method } = router.routes[
-          j
-        ];
+        const {
+          path: childPath,
+          middlewarePath,
+          fns,
+          method,
+        } = router.routes[j];
 
         const path = (route + (childPath || middlewarePath || '')).replace(
           /\/{1,}/g,
@@ -210,6 +213,11 @@ class Router {
           if (typeof fn === 'function' && fn.length === 4)
             return fn(error, req, res, next);
 
+          const nextFn = handlers[id];
+          if (typeof nextFn === 'function' && nextFn.length === 4) {
+            return nextFn(error, req, res, next);
+          }
+
           return res.send(error.stack, error.status || 500);
         }
 

tests/error-handling/custom.js

@@ -0,0 +1,23 @@
+const pureHttp = require('../..');
+
+module.exports = function () {
+  const app = pureHttp();
+
+  app.get(
+    '/custom',
+    (_req, _res, _next) => {
+      throw new Error('bad');
+    },
+    /* istanbul ignore next */
+    // ignore coverage for this function because it will never be called.
+    (req, res, _next) => {
+      res.send('good');
+    },
+  );
+
+  app.use((error, req, res, _next) => {
+    res.send('Something went wrong.', 500);
+  });
+
+  return app;
+};

tests/error-handling/custom.test.js

@@ -0,0 +1,16 @@
+/* eslint-disable global-require */
+/* eslint-disable no-unused-vars */
+const supertest = require('supertest');
+
+describe('ALL /not-found', () => {
+  it(`The status should be 404.`, async () => {
+    const app = require('./custom')();
+
+    const request = supertest(app);
+
+    const res = await request.get('/custom');
+
+    expect(res.statusCode).toBe(500);
+    expect(res.text).toBe('Something went wrong.');
+  });
+});