REFACTOR: Move option to return emails into the serializer

This makes more sense than having the guardian take an accessor.
The logic belongs in the Serializer, where the JSON is calculated.

Also removed some of the DRYness in the spec. It's fewer lines
and made it easier to test the option on the serializer.

app/controllers/admin/users_controller.rb

@@ -32,12 +32,13 @@ class Admin::UsersController < Admin::AdminController
   def index
     users = ::AdminUserIndexQuery.new(params).find_users
 
+    opts = {}
     if params[:show_emails] == "true"
-      guardian.can_see_emails = true
       StaffActionLogger.new(current_user).log_show_emails(users)
+      opts[:emails_desired] = true
     end
 
-    render_serialized(users, AdminUserListSerializer)
+    render_serialized(users, AdminUserListSerializer, opts)
   end
 
   def show

app/serializers/admin_user_list_serializer.rb

@@ -39,7 +39,7 @@ class AdminUserListSerializer < BasicUserSerializer
   def include_email?
     # staff members can always see their email
     (scope.is_staff? && (object.id == scope.user.id || object.staged?)) ||
-    (scope.is_admin? && scope.can_see_emails?)
+      (scope.is_admin? && @options[:emails_desired])
   end
 
   alias_method :include_secondary_emails?, :include_email?

lib/guardian.rb

@@ -54,7 +54,6 @@ class Guardian
     end
   end
 
-  attr_accessor :can_see_emails
   attr_reader :request
 
   def initialize(user = nil, request = nil)
@@ -381,10 +380,6 @@ class Guardian
     )
   end
 
-  def can_see_emails?
-    @can_see_emails
-  end
-
   def can_export_entity?(entity)
     return false unless @user
     return true if is_admin?

spec/serializers/admin_user_list_serializer_spec.rb

@@ -8,92 +8,59 @@ describe AdminUserListSerializer do
     let(:moderator) { Fabricate(:user_single_email, moderator: true, email: "moderator@email.com") }
     let(:user) { Fabricate(:user_single_email, email: "user@email.com") }
     let(:guardian) { Guardian.new(admin) }
-    let(:mod_guardian) { Guardian.new(moderator) }
 
-    let(:json) do
-      AdminUserListSerializer.new(user,
-        scope: guardian,
-        root: false
-      ).as_json
+    let(:serializer) do
+      AdminUserListSerializer.new(user, scope: guardian, root: false)
     end
 
-    let(:mod_json) do
-      AdminUserListSerializer.new(user,
-        scope: mod_guardian,
-        root: false
+    def serialize(user, viewed_by, opts = nil)
+      AdminUserListSerializer.new(
+        user,
+        scope: Guardian.new(viewed_by),
+        root: false,
+        emails_desired: opts && opts[:emails_desired]
       ).as_json
     end
 
     def fabricate_secondary_emails_for(u)
-      ["first", "second"].each do |name|
-        Fabricate(:secondary_email, user: u, email: "#{name}@email.com")
-      end
+      Fabricate(:secondary_email, user: u, email: "first@email.com")
+      Fabricate(:secondary_email, user: u, email: "second@email.com")
     end
 
-    shared_examples "shown" do |email|
-      it "contains emails" do
-        expect(json[:email]).to eq(email)
-
-        expect(json[:secondary_emails]).to contain_exactly(
-          "first@email.com",
-          "second@email.com"
-        )
-      end
+    it "contains an admin's own emails" do
+      fabricate_secondary_emails_for(admin)
+      json = serialize(admin, admin)
+      expect(json[:email]).to eq("admin@email.com")
+      expect(json[:secondary_emails]).to contain_exactly("first@email.com", "second@email.com")
     end
 
-    shared_examples "not shown" do
-      it "doesn't contain emails" do
-        expect(json[:email]).to eq(nil)
-        expect(json[:secondary_emails]).to eq(nil)
-      end
+    it "doesn't include a regular user's emails" do
+      fabricate_secondary_emails_for(user)
+      json = serialize(user, user)
+      expect(json[:email]).to eq(nil)
+      expect(json[:secondary_emails]).to eq(nil)
     end
 
-    context "with myself" do
-      let(:user) { admin }
-
-      before do
-        fabricate_secondary_emails_for(admin)
-      end
-
-      include_examples "shown", "admin@email.com"
+    it "doesn't return emails for a moderator request" do
+      fabricate_secondary_emails_for(user)
+      json = serialize(user, moderator, emails_desired: true)
+      expect(json[:email]).to eq(nil)
+      expect(json[:secondary_emails]).to eq(nil)
     end
 
-    context "with a normal user" do
-      before do
-        fabricate_secondary_emails_for(user)
-      end
-
-      include_examples "not shown"
+    it "returns emails for admins when emails_desired is true" do
+      fabricate_secondary_emails_for(user)
+      json = serialize(user, admin, emails_desired: true)
+      expect(json[:email]).to eq("user@email.com")
+      expect(json[:secondary_emails]).to contain_exactly("first@email.com", "second@email.com")
     end
 
-    context "when moderator makes a request with show_emails param set to true" do
-      before do
-        mod_guardian.can_see_emails = true
-        fabricate_secondary_emails_for(user)
-      end
-
-      it "doesn't contain emails" do
-        expect(mod_json[:email]).to eq(nil)
-        expect(mod_json[:secondary_emails]).to eq(nil)
-      end
-    end
-
-    context "with a normal user after clicking 'show emails'" do
-      before do
-        guardian.can_see_emails = true
-        fabricate_secondary_emails_for(user)
-      end
-
-      include_examples "shown", "user@email.com"
-    end
-
-    context "with a staged user" do
-      before do
-        user.staged = true
-        fabricate_secondary_emails_for(user)
-      end
-
-      include_examples "shown", "user@email.com"
+    it "returns a staged user's emails" do
+      user.staged = true
+      fabricate_secondary_emails_for(user)
+      json = serialize(user, admin)
+      expect(json[:email]).to eq("user@email.com")
+      expect(json[:secondary_emails]).to contain_exactly("first@email.com", "second@email.com")
     end
   end
 end