Refactored the domain separator regex, plus syntax and grammar fixes.

app/models/application_setting.rb

@@ -4,6 +4,12 @@ class ApplicationSetting < ActiveRecord::Base
   add_authentication_token_field :health_check_access_token
 
   CACHE_KEY = 'application_setting.last'
+  DOMAIN_LIST_SEPARATOR = %r{\s*[,;]\s*     # comma or semicolon, optionally surrounded by whitespace
+                            |               # or
+                            \s              # any whitespace character
+                            |               # or
+                            [\r\n]          # any number of newline characters
+                          }x
 
   serialize :restricted_visibility_levels
   serialize :import_sources
@@ -164,25 +170,18 @@ class ApplicationSetting < ActiveRecord::Base
     self.domain_blacklist.join("\n") unless self.domain_blacklist.nil?
   end
 
-  def splitter
-    /\s*[,;]\s*     # comma or semicolon, optionally surrounded by whitespace
-      |               # or
-      \s              # any whitespace character
-      |               # or
-      [\r\n]          # any number of newline characters
-    /x
-  end
-
   def restricted_signup_domains_raw=(values)
     self.restricted_signup_domains = []
-    self.restricted_signup_domains = values.split(splitter)
+    self.restricted_signup_domains = values.split(DOMAIN_LIST_SEPARATOR)
     self.restricted_signup_domains.reject! { |d| d.empty? }
+    self.restricted_signup_domains
   end
 
   def domain_blacklist_raw=(values)
     self.domain_blacklist = []
-    self.domain_blacklist = values.split(splitter)
+    self.domain_blacklist = values.split(DOMAIN_LIST_SEPARATOR)
     self.domain_blacklist.reject! { |d| d.empty? }
+    self.domain_blacklist
   end
 
   def domain_blacklist_file=(file)

doc/administration/access_restrictions.md

@@ -39,7 +39,7 @@ not selected.
 
 ## Blacklist email domains
 
-With this feature enabled, you can block email addresses of an specific domain
+With this feature enabled, you can block email addresses of a specific domain
 from creating an account on your GitLab server. This is particularly useful to
 prevent spam. Disposable email addresses are usually used by malicious users to
 create dummy accounts and spam issues.

spec/models/application_setting_spec.rb

@@ -77,27 +77,27 @@ describe ApplicationSetting, models: true do
   context 'blacklisted signup domains' do
     it 'set single domain' do
       setting.domain_blacklist_raw = 'example.com'
-      expect(setting.domain_blacklist).to eq(['example.com'])
+      expect(setting.domain_blacklist).to contain_exactly('example.com')
     end
 
     it 'set multiple domains with spaces' do
       setting.domain_blacklist_raw = 'example.com *.example.com'
-      expect(setting.domain_blacklist).to eq(['example.com', '*.example.com'])
+      expect(setting.domain_blacklist).to contain_exactly('example.com', '*.example.com')
     end
 
     it 'set multiple domains with newlines and a space' do
       setting.domain_blacklist_raw = "example.com\n *.example.com"
-      expect(setting.domain_blacklist).to eq(['example.com', '*.example.com'])
+      expect(setting.domain_blacklist).to contain_exactly('example.com', '*.example.com')
     end
 
     it 'set multiple domains with commas' do
       setting.domain_blacklist_raw = "example.com, *.example.com"
-      expect(setting.domain_blacklist).to eq(['example.com', '*.example.com'])
+      expect(setting.domain_blacklist).to contain_exactly('example.com', '*.example.com')
     end
 
     it 'set multiple domain with file' do
       setting.domain_blacklist_file = File.open(Rails.root.join('spec/fixtures/', 'blacklist.txt'))
-      expect(setting.domain_blacklist).to eq(%w(example.com test.com foo.bar))
+      expect(setting.domain_blacklist).to contain_exactly('example.com', 'test.com', 'foo.bar')
     end
   end
 end

spec/models/user_spec.rb

@@ -89,7 +89,7 @@ describe User, models: true do
     end
 
     describe 'email' do
-      context 'when no signup domains white listed' do
+      context 'when no signup domains whitelisted' do
         before do
           allow_any_instance_of(ApplicationSetting).to receive(:restricted_signup_domains).and_return([])
         end
@@ -100,7 +100,7 @@ describe User, models: true do
         end
       end
 
-      context 'when a signup domain is white listed and subdomains are allowed' do
+      context 'when a signup domain is whitelisted and subdomains are allowed' do
         before do
           allow_any_instance_of(ApplicationSetting).to receive(:restricted_signup_domains).and_return(['example.com', '*.example.com'])
         end
@@ -121,7 +121,7 @@ describe User, models: true do
         end
       end
 
-      context 'when a signup domain is white listed and subdomains are not allowed' do
+      context 'when a signup domain is whitelisted and subdomains are not allowed' do
         before do
           allow_any_instance_of(ApplicationSetting).to receive(:restricted_signup_domains).and_return(['example.com'])
         end