修正appliation.coffee中写法的错误

Gemfile

@@ -4,8 +4,8 @@ source 'https://gems.ruby-china.org'
 gem 'rails', '~> 5.0.0', '>= 5.0.0.1'
 
 gem 'sprockets'
+gem 'bootstrap-sass','~> 3.3.6'
 gem 'sass-rails', '~> 5.0'
-gem 'bootstrap','~> 4.0.0.alpha4'
 
 gem 'uglifier', '>= 1.3.0'
 gem 'coffee-rails', '~> 4.2'

Gemfile.lock

@@ -41,9 +41,9 @@ GEM
     arel (7.1.2)
     autoprefixer-rails (6.5.0.2)
       execjs
-    bootstrap (4.0.0.alpha4)
-      autoprefixer-rails (>= 6.0.3)
-      sass (>= 3.4.19)
+    bootstrap-sass (3.3.7)
+      autoprefixer-rails (>= 5.2.1)
+      sass (>= 3.3.4)
     builder (3.2.2)
     byebug (9.0.6)
     coffee-rails (4.2.1)
@@ -159,7 +159,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
-  bootstrap (~> 4.0.0.alpha4)
+  bootstrap-sass (~> 3.3.6)
   byebug
   coffee-rails (~> 4.2)
   jbuilder (~> 2.5)

app/assets/javascripts/application.coffee

@@ -1,6 +1,6 @@
-//
-//= require jquery
-//= require jquery_ujs
-//= require turbolinks
-//= require_tree .
-//
+#= require jquery
+#= require jquery_ujs
+#= require bootstrap-sprockets
+#= require turbolinks
+#= require_tree .
+

app/assets/javascripts/home.coffee

@@ -0,0 +1,3 @@
+# Place all the behaviors and hooks related to the matching controller here.
+# All this logic will automatically be available in application.js.
+# You can use CoffeeScript in this file: http://coffeescript.org/

app/assets/stylesheets/application.scss

@@ -2,5 +2,6 @@
  *= require_tree .
  *= require_self
  */
+@import "bootstrap-sprockets";
 @import "bootstrap";
 

app/controllers/home_controller.rb

@@ -0,0 +1,5 @@
+class HomeController < ApplicationController
+  def index 
+#    render html:"hello world"
+  end
+end

app/helpers/home_helper.rb

@@ -0,0 +1,2 @@
+module HomeHelper
+end

app/views/home/index.html.erb

@@ -0,0 +1,8 @@
+<header class="col-md-4">
+    <h1 class="col-md-5">Welcome to the Sample App</h1>
+    <h2>
+        This is the home page for the
+      <a href="http://www.railstutorial.org/">Ruby on Rails Tutorial</a>
+       sample application.
+    </h2>
+</header>

config/routes.rb

@@ -1,2 +1,3 @@
 Rails.application.routes.draw do
+  root 'home#index'
 end

test/controllers/home_controller_test.rb

@@ -0,0 +1,7 @@
+require 'test_helper'
+
+class HomeControllerTest < ActionDispatch::IntegrationTest
+  # test "the truth" do
+  #   assert true
+  # end
+end