Fix: Ensure .use() middleware works when path or prefix contains parameters (#203)

* fix: parameter in path of .use

* fix: parameter in prefix

Author: MiccWan

lib/layer.js

@@ -44,7 +44,7 @@ module.exports = class Layer {
 
     if (this.opts.pathAsRegExp === true) {
       this.regexp = new RegExp(path);
-    } else if (this.path) {
+    } else {
       if ('strict' in this.opts) {
         // path-to-regexp renamed strict to trailing in v8.1.0
         this.opts.trailing = this.opts.strict !== true;
@@ -224,18 +224,16 @@ module.exports = class Layer {
    * @private
    */
   setPrefix(prefix) {
-    if (this.path) {
-      this.path =
-        this.path !== '/' || this.opts.strict === true
-          ? `${prefix}${this.path}`
-          : prefix;
-      if (this.opts.pathAsRegExp === true || prefix instanceof RegExp) {
-        this.regexp = new RegExp(this.path);
-      } else if (this.path) {
-        const { regexp, keys } = pathToRegexp(this.path, this.opts);
-        this.regexp = regexp;
-        this.paramNames = keys;
-      }
+    this.path =
+      this.path !== '/' || this.opts.strict === true
+        ? `${prefix}${this.path}`
+        : prefix;
+    if (this.opts.pathAsRegExp === true || prefix instanceof RegExp) {
+      this.regexp = new RegExp(this.path);
+    } else if (this.path) {
+      const { regexp, keys } = pathToRegexp(this.path, this.opts);
+      this.regexp = regexp;
+      this.paramNames = keys;
     }
 
     return this;

lib/router.js

@@ -168,10 +168,10 @@ class Router {
         const routerPrefixHasParam = Boolean(
           router.opts.prefix && keys.length > 0
         );
-        router.register(path || '([^/]*)', [], m, {
+        router.register(path || '', [], m, {
           end: false,
           ignoreCaptures: !hasPath && !routerPrefixHasParam,
-          pathAsRegExp: true
+          pathAsRegExp: hasPath ? path instanceof RegExp : false
         });
       }
     }

test/lib/layer.js

@@ -291,34 +291,16 @@ describe('Layer', () => {
       });
       assert.strictEqual(url, '/programming/how%20to%20node%20%26%20js%2Fts');
     });
-
-    it('setPrefix method checks Layer for path', () => {
-      const route = new Layer('/category', ['get'], [() => {}], {
-        name: 'books'
-      });
-      route.path = '/hunter2';
-      const prefix = route.setPrefix('TEST');
-      assert.strictEqual(prefix.path, 'TEST/hunter2');
-    });
   });
 
   describe('Layer#prefix', () => {
-    it('setPrefix method passes check Layer for path', () => {
-      const route = new Layer('/category', ['get'], [() => {}], {
+    it('setPrefix method checks Layer for path', () => {
+      const route = new Layer('/category', ['get'], [() => { }], {
         name: 'books'
       });
       route.path = '/hunter2';
       const prefix = route.setPrefix('/TEST');
       assert.strictEqual(prefix.path, '/TEST/hunter2');
     });
-
-    it('setPrefix method fails check Layer for path', () => {
-      const route = new Layer(false, ['get'], [() => {}], {
-        name: 'books'
-      });
-      route.path = false;
-      const prefix = route.setPrefix('/TEST');
-      assert.strictEqual(prefix.path, false);
-    });
   });
 });

test/lib/router.js

@@ -1048,6 +1048,27 @@ describe('Router#use()', () => {
     assert.strictEqual(res.body.foobar, 'foobar');
   });
 
+  it('uses router middleware at given path with parameters - koajs/router#gh-202', async () => {
+    const app = new Koa();
+    const router = new Router();
+    router.use('/:foo/:bar', (ctx, next) => {
+      ctx.foo = ctx.params.foo;
+      ctx.bar = ctx.params.bar;
+      return next();
+    });
+    router.get('/:foo/:bar', (ctx) => {
+      ctx.body = {
+        foobar: ctx.foo + ctx.bar
+      };
+    });
+    app.use(router.routes());
+    const res = await request(http.createServer(app.callback()))
+      .get('/qux/baz')
+      .expect(200);
+
+    assert.strictEqual(res.body.foobar, 'quxbaz');
+  });
+
   it('runs router middleware before subrouter middleware', async () => {
     const app = new Koa();
     const router = new Router();
@@ -1911,17 +1932,20 @@ describe('Router#prefix', () => {
         assert.strictEqual('params' in ctx, true);
         assert.strictEqual(typeof ctx.params, 'object');
         assert.strictEqual(ctx.params.category, 'cats');
+        ctx.category = ctx.params.category;
         return next();
       })
       .get('/suffixHere', (ctx) => {
         assert.strictEqual('params' in ctx, true);
         assert.strictEqual(typeof ctx.params, 'object');
         assert.strictEqual(ctx.params.category, 'cats');
-        ctx.status = 204;
+        ctx.status = 200;
+        ctx.body = ctx.category;
       });
-    await request(http.createServer(app.callback()))
+    const res = await request(http.createServer(app.callback()))
       .get('/cats/suffixHere')
-      .expect(204);
+      .expect(200);
+    assert.strictEqual(res.text, 'cats');
   });
 
   it('populates ctx.params correctly for more complex router prefix (including use)', async () => {