Add tests for matchRoutes middleware in auto-routing.js (#79)

Adding tests for the matchRoutes middleware in auto-routing.js

- [x] Create test file for auto-routing middleware
- [x] Add test setup with Express and Nunjucks configuration
- [x] Add tests for root path routing
- [x] Add tests for simple path routing
- [x] Add test for simple path with .html extension
- [x] Add tests for nested path routing (folder with index)
- [x] Add tests for non-existent paths (404 scenarios)
- [x] Add tests for template errors
- [x] Run tests to verify they pass (55 tests total, all passing)
- [x] Run linter to ensure code style is correct (all checks pass)
- [x] Refactor to match existing test patterns exactly
- [x] Use underscore prefix for unused parameters per code review
feedback

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<details>

<summary>Original prompt</summary>

> 
> ----
> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>Add tests for the matchRoutes middleware</issue_title>
> <issue_description>The `lib/express-middleware/auto-routing.js` file
needs some tests to be added within `tests/express-middleware/`,
following the existing test patterns.</issue_description>
> 
> <agent_instructions>Use the built-in node:test and node:assert
libraries.</agent_instructions>
> 
> ## Comments on the Issue (you are @copilot in this section)
> 
> <comments>
> </comments>
> 


</details>

- Fixes #78

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Author: Copilot

package-lock.json

@@ -0,0 +1,116 @@
+const assert = require('node:assert')
+const http = require('node:http')
+const { join } = require('node:path')
+const { describe, it } = require('node:test')
+
+const express = require('express')
+const nunjucks = require('nunjucks')
+const request = require('supertest')
+
+const { matchRoutes } = require('../../lib/express-middleware/auto-routing')
+
+describe('matchRoutes', () => {
+  // Create test templates directory
+  const templatesDir = join(__dirname, 'test-templates')
+
+  // Setup Express app with Nunjucks
+  const app = express()
+  app.set('view engine', 'html')
+  nunjucks.configure([templatesDir], {
+    express: app,
+    noCache: true
+  })
+
+  // Add the matchRoutes middleware
+  app.use(matchRoutes)
+
+  // Add 404 handler
+  app.use((req, res) => {
+    res.status(404).send('Not found')
+  })
+
+  // Add error handler
+  app.use((_err, _req, res, _next) => {
+    res.status(500).send('Template error')
+  })
+
+  const server = http.createServer(app)
+
+  describe('root path', () => {
+    it('should render index.html for root path', async () => {
+      const response = await request(server).get('/')
+      assert.strictEqual(response.status, 200)
+      assert.strictEqual(response.text, 'Test index page\n')
+      assert.strictEqual(
+        response.headers['content-type'],
+        'text/html; charset=utf-8'
+      )
+    })
+  })
+
+  describe('simple path', () => {
+    it('should render simple.html for /simple path', async () => {
+      const response = await request(server).get('/simple')
+      assert.strictEqual(response.status, 200)
+      assert.strictEqual(response.text, 'Simple test page\n')
+      assert.strictEqual(
+        response.headers['content-type'],
+        'text/html; charset=utf-8'
+      )
+    })
+
+    it('should render simple.html for /simple.html path', async () => {
+      const response = await request(server).get('/simple.html')
+      assert.strictEqual(response.status, 200)
+      assert.strictEqual(response.text, 'Simple test page\n')
+      assert.strictEqual(
+        response.headers['content-type'],
+        'text/html; charset=utf-8'
+      )
+    })
+  })
+
+  describe('nested path with index', () => {
+    it('should render nested/index.html for /nested path', async () => {
+      const response = await request(server).get('/nested')
+      assert.strictEqual(response.status, 200)
+      assert.strictEqual(response.text, 'Nested index page\n')
+      assert.strictEqual(
+        response.headers['content-type'],
+        'text/html; charset=utf-8'
+      )
+    })
+
+    it('should render nested/index.html for /nested/ path with trailing slash', async () => {
+      const response = await request(server).get('/nested/')
+      assert.strictEqual(response.status, 200)
+      assert.strictEqual(response.text, 'Nested index page\n')
+      assert.strictEqual(
+        response.headers['content-type'],
+        'text/html; charset=utf-8'
+      )
+    })
+  })
+
+  describe('non-existent paths', () => {
+    it('should call next() for non-existent template', async () => {
+      const response = await request(server).get('/does-not-exist')
+      assert.strictEqual(response.status, 404)
+      assert.strictEqual(response.text, 'Not found')
+    })
+
+    it('should call next() for non-existent nested path', async () => {
+      const response = await request(server).get('/path/does/not/exist')
+      assert.strictEqual(response.status, 404)
+      assert.strictEqual(response.text, 'Not found')
+    })
+  })
+
+  describe('template errors', () => {
+    it('should call next(error) for template rendering errors', async () => {
+      const response = await request(server).get('/error')
+      assert.strictEqual(response.status, 500)
+      assert.strictEqual(response.text, 'Template error')
+    })
+  })
+})

tests/express-middleware/auto-routing.test.js

@@ -0,0 +1 @@
+{% unknown_tag %}

tests/express-middleware/test-templates/error.html

@@ -0,0 +1 @@
+Test index page

tests/express-middleware/test-templates/index.html

@@ -0,0 +1 @@
+Nested index page

tests/express-middleware/test-templates/nested/index.html

@@ -0,0 +1 @@
+Simple test page