fix: log full error object in logerror (fixes #6462)

lib/application.js

@@ -614,7 +614,7 @@ app.listen = function listen() {
 
 function logerror(err) {
   /* istanbul ignore next */
-  if (this.get('env') !== 'test') console.error(err.stack || err.toString());
+  if (this.get('env') !== 'test') console.error(err);
 }
 
 /**

test/app.logerror.js

@@ -0,0 +1,47 @@
+'use strict'
+
+var assert = require('node:assert')
+var express = require('..')
+var request = require('supertest')
+
+describe('logerror', function () {
+  var original
+
+  beforeEach(function () {
+    original = console.error
+  })
+
+  afterEach(function () {
+    if (original) {
+      console.error = original
+    }
+  })
+
+  it('should log the full error object', function (done) {
+    var app = express()
+    app.set('env', 'development')
+
+    var logged
+    console.error = function (err) {
+      logged = err
+    }
+
+    app.use(function (req, res, next) {
+      var inner = new Error('inner')
+      next(new Error('outer', { cause: inner }))
+    })
+
+    request(app)
+      .get('/')
+      .expect(500, function (err) {
+        if (err) return done(err)
+        setImmediate(function () {
+          assert.ok(logged instanceof Error)
+          assert.strictEqual(logged.message, 'outer')
+          assert.ok(logged.cause instanceof Error)
+          assert.strictEqual(logged.cause.message, 'inner')
+          done()
+        })
+      })
+  })
+})