'use strict';

const request = require('supertest');
const Koa = require('../..');

describe('app.use(fn)', function(){
  it('should compose middleware', function(done){
    const app = new Koa();
    const calls = [];

    app.use(function(ctx, next){
      calls.push(1);
      return next().then(function(){
        calls.push(6);
      });
    });

    app.use(function(ctx, next){
      calls.push(2);
      return next().then(function(){
        calls.push(5);
      });
    });

    app.use(function(ctx, next){
      calls.push(3);
      return next().then(function(){
        calls.push(4);
      });
    });

    const server = app.listen();

    request(server)
      .get('/')
      .expect(404)
      .end(function(err){
        if (err) return done(err);
        calls.should.eql([1, 2, 3, 4, 5, 6]);
        done();
      });
  });

  // https://github.com/koajs/koa/pull/530#issuecomment-148138051
  it('should catch thrown errors in non-async functions', function(done){
    const app = new Koa();

    app.use(ctx => {
      ctx.throw('Not Found', 404);
    });

    request(app.listen())
      .get('/')
      .expect(404)
      .end(done);
  });

  it('should throw error for non function', function(done){
    const app = new Koa();

    (() => app.use('not a function')).should.throw('middleware must be a function!');
    done();
  });

  it('should throw error for generator', function(){
    const app = new Koa();

    (() => app.use(function *(){})).should.throw('Support for generators has been removed. Use Promises or wrap your generator with co.wrap');
  });
});