テストが通らない原因を知りたい。

・使用環境
AWS（cloud9）、rails 5.1.6、Ruby

・現在取り組んでいること（教材など含む）
rails tutorial6章6.3セキュアなパスワードを追加する。

・やりたいこと・解決したいこと
リスト6.40まで終わり、テストを実行したらエラーが8つ出てきて、解決方法を知りたい。

・うまくいっていない内容・すでに実行したこと
エラー内容

Ruby
1コード
2Finished in 0.569128s, 24.5991 runs/s, 24.5991 assertions/s.
3
4  1) Error:
5UserTest#test_email_addresses_should_be_unique:
6NoMethodError: undefined method `password_digest=' for #<User:0x0000000006969d48>
7Did you mean?  password=
8    test/models/user_test.rb:5:in `setup'
9
10  2) Error:
11UserTest#test_name_should_not_be_too_long:
12NoMethodError: undefined method `password_digest=' for #<User:0x0000000006a216c8>
13Did you mean?  password=
14    test/models/user_test.rb:5:in `setup'
15
16  3) Error:
17UserTest#test_email_validation_should_accept_valid_addresses:
18NoMethodError: undefined method `password_digest=' for #<User:0x0000000006a33300>
19Did you mean?  password=
20    test/models/user_test.rb:5:in `setup'
21
22  4) Error:
23UserTest#test_email_validation_should_reject_invalid_addresses:
24NoMethodError: undefined method `password_digest=' for #<User:0x0000000006a39250>
25Did you mean?  password=
26    test/models/user_test.rb:5:in `setup'
27
28  5) Error:
29UserTest#test_name_should_be_present:
30NoMethodError: undefined method `password_digest=' for #<User:0x0000000006a4ae60>
31Did you mean?  password=
32    test/models/user_test.rb:5:in `setup'
33
34  6) Error:
35UserTest#test_email_should_not_be_too_long:
36NoMethodError: undefined method `password_digest=' for #<User:0x0000000006a50c48>
37Did you mean?  password=
38    test/models/user_test.rb:5:in `setup'
39
40  7) Error:
41UserTest#test_should_be_valid?:
42NoMethodError: undefined method `password_digest=' for #<User:0x0000000006a62880>
43Did you mean?  password=
44    test/models/user_test.rb:5:in `setup'
45
46  8) Error:
47UserTest#test_email_should_be_present:
48NoMethodError: undefined method `password_digest=' for #<User:0x0000000006a68668>
49Did you mean?  password=
50    test/models/user_test.rb:5:in `setup'
51
5214 runs, 14 assertions, 0 failures, 8 errors, 0 skips
53
54user_test.rbファイル
55
56コード
57require 'test_helper'
58
59class UserTest < ActiveSupport::TestCase
60  def setup
61    @user = User.new(name: "Example User", email: "user@example.com",
62                     password: "foobar", password_confirmation: "foobar")
63  end
64  
65  test "should be valid?" do
66    assert @user.valid?
67  end
68  
69  test "name should be present" do
70    @user.name = "   "
71    assert_not @user.valid?
72  end
73  
74  test "email should be present" do
75    @user.email = "   "
76    assert_not @user.valid?
77  end
78  
79  test "name should not be too long" do
80    @user.name = "a" * 51
81    assert_not @user.valid?
82  end
83  
84  test "email should not be too long" do
85    @user.email = "a" * 244 + "@example.com"
86    assert_not @user.valid?
87  end
88  
89  test "email validation should accept valid addresses" do
90    valid_addresses = %w[user@example.com USER@foo.COM A_US-ER@foo.bar.org
91                         first.last@foo.jp alice+bob@baz.cn]
92    valid_addresses.each do |valid_address|
93      @user.email = valid_address
94      assert @user.valid?, "#{valid_address.inspect} should be valid"
95    end
96  end
97  
98  test "email validation should reject invalid addresses" do
99    invalid_addresses = %w[user@example,com user_at_foo.org user.name@example.
100                           foo@bar_baz.com foo@bar+baz.com]
101    invalid_addresses.each do |invalid_address|
102      @user.email = invalid_address
103      assert_not @user.valid?, "#{invalid_address.inspect} should be invalid"
104    end
105  end
106  
107  test "email addresses should be unique" do
108    duplicate_user = @user.dup
109    duplicate_user.email = @user.email.upcase
110    @user.save
111    assert_not duplicate_user.valid?
112  end
113  
114end
115
116user.rbファイル
117コード
118class User < ApplicationRecord
119  before_save { self.email = email.downcase }
120  validates :name, presence: true, length: { maximum: 50 }
121  VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+.[a-z]+\z/i
122  validates :email, presence: true, length: { maximum: 255 },
123                    format: { with: VALID_EMAIL_REGEX },
124                    uniqueness: { case_sensitive: false }
125  has_secure_password
126end
127
128構文が間違えていないか確認（特に間違っていないと思いますが）、マイグレートを再度実行、バンドルインストールしたが正常にインストールされた。
129
130・自身の仮説
131マイグレートが成功したらschema.rbファイルにpassword_digestが追加されると思うので、マイグレートが正しく実行できていないかもしれません。
132
133以上になります。よろしくお願いいたします。