fixes remaining RuboCop issues [Vipul A M, Xavier Noria]

40 files changed, 71 insertions, 71 deletions

diff --git a/actioncable/Rakefile b/actioncable/Rakefile
index 34649547a2..648de57004 100644
--- a/actioncable/Rakefile
+++ b/actioncable/Rakefile
@@ -21,7 +21,7 @@ namespace :test do
   task :isolated do
     Dir.glob("test/**/*_test.rb").all? do |file|
       sh(Gem.ruby, "-w", "-Ilib:test", file)
-    end or raise "Failures"
+    end || raise("Failures")
   end
 
   task :integration do
diff --git a/actioncable/lib/action_cable/connection/client_socket.rb b/actioncable/lib/action_cable/connection/client_socket.rb
index c48f000d9c..70a2bbecb1 100644
--- a/actioncable/lib/action_cable/connection/client_socket.rb
+++ b/actioncable/lib/action_cable/connection/client_socket.rb
@@ -89,7 +89,7 @@ module ActionCable
         code   ||= 1000
         reason ||= ""
 
-        unless code == 1000 or (code >= 3000 and code <= 4999)
+        unless code == 1000 || (code >= 3000 && code <= 4999)
           raise ArgumentError, "Failed to execute 'close' on WebSocket: " +
                                "The code must be either 1000, or between 3000 and 4999. " +
                                "#{code} is neither."
diff --git a/actionmailer/Rakefile b/actionmailer/Rakefile
index 059d98fb28..6f05d236d9 100644
--- a/actionmailer/Rakefile
+++ b/actionmailer/Rakefile
@@ -18,6 +18,6 @@ namespace :test do
   task :isolated do
     Dir.glob("test/**/*_test.rb").all? do |file|
       sh(Gem.ruby, "-w", "-Ilib:test", file)
-    end or raise "Failures"
+    end || raise("Failures")
   end
 end
diff --git a/actionpack/Rakefile b/actionpack/Rakefile
index 4bbbcfe9ff..31dd1865f9 100644
--- a/actionpack/Rakefile
+++ b/actionpack/Rakefile
@@ -21,7 +21,7 @@ namespace :test do
   task :isolated do
     test_files.all? do |file|
       sh(Gem.ruby, "-w", "-Ilib:test", file)
-    end or raise "Failures"
+    end || raise("Failures")
   end
 end
 
diff --git a/actionpack/lib/action_controller/metal/data_streaming.rb b/actionpack/lib/action_controller/metal/data_streaming.rb
index 6a1acb64f7..f089c8423b 100644
--- a/actionpack/lib/action_controller/metal/data_streaming.rb
+++ b/actionpack/lib/action_controller/metal/data_streaming.rb
@@ -64,7 +64,7 @@ module ActionController #:nodoc:
       # http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9
       # for the Cache-Control header spec.
       def send_file(path, options = {}) #:doc:
-        raise MissingFile, "Cannot read file #{path}" unless File.file?(path) and File.readable?(path)
+        raise MissingFile, "Cannot read file #{path}" unless File.file?(path) && File.readable?(path)
 
         options[:filename] ||= File.basename(path) unless options[:url_based_filename]
         send_file_headers! options
diff --git a/actionpack/lib/action_controller/metal/implicit_render.rb b/actionpack/lib/action_controller/metal/implicit_render.rb
index 4137db99ea..e7e32e5108 100644
--- a/actionpack/lib/action_controller/metal/implicit_render.rb
+++ b/actionpack/lib/action_controller/metal/implicit_render.rb
@@ -61,7 +61,7 @@ module ActionController
 
     def method_for_action(action_name)
       super || if template_exists?(action_name.to_s, _prefixes)
-        "default_render"
+                 "default_render"
       end
     end
 
diff --git a/actionpack/lib/action_controller/metal/redirecting.rb b/actionpack/lib/action_controller/metal/redirecting.rb
index 3c7cc15627..2bd4296aff 100644
--- a/actionpack/lib/action_controller/metal/redirecting.rb
+++ b/actionpack/lib/action_controller/metal/redirecting.rb
@@ -111,7 +111,7 @@ module ActionController
           `fallback_location` represents the location to use if the request has
           no HTTP referer information.
         MESSAGE
-        request.headers["Referer"] or raise RedirectBackError
+        request.headers["Referer"] || raise(RedirectBackError)
       when Proc
         _compute_redirect_to_location request, options.call
       else
diff --git a/actionpack/lib/action_dispatch/middleware/session/cache_store.rb b/actionpack/lib/action_dispatch/middleware/session/cache_store.rb
index d99c2fd411..71274bc13a 100644
--- a/actionpack/lib/action_dispatch/middleware/session/cache_store.rb
+++ b/actionpack/lib/action_dispatch/middleware/session/cache_store.rb
@@ -19,7 +19,7 @@ module ActionDispatch
 
       # Get a session from the cache.
       def find_session(env, sid)
-        unless sid and session = @cache.read(cache_key(sid))
+        unless sid && (session = @cache.read(cache_key(sid)))
           sid, session = generate_sid, {}
         end
         [sid, session]
diff --git a/actionpack/lib/action_dispatch/routing/mapper.rb b/actionpack/lib/action_dispatch/routing/mapper.rb
index 67b9463a6a..4ec1b8ee1f 100644
--- a/actionpack/lib/action_dispatch/routing/mapper.rb
+++ b/actionpack/lib/action_dispatch/routing/mapper.rb
@@ -1607,7 +1607,7 @@ module ActionDispatch
         def root(path, options = {})
           if path.is_a?(String)
             options[:to] = path
-          elsif path.is_a?(Hash) and options.empty?
+          elsif path.is_a?(Hash) && options.empty?
             options = path
           else
             raise ArgumentError, "must be called with a path and/or options"
diff --git a/actionpack/lib/action_dispatch/routing/route_set.rb b/actionpack/lib/action_dispatch/routing/route_set.rb
index 112a38b868..864ffe3a79 100644
--- a/actionpack/lib/action_dispatch/routing/route_set.rb
+++ b/actionpack/lib/action_dispatch/routing/route_set.rb
@@ -596,8 +596,8 @@ module ActionDispatch
         # :controller, :action or :id is not found, don't pull any
         # more keys from the recall.
         def normalize_controller_action_id!
-          use_recall_for(:controller) or return
-          use_recall_for(:action) or return
+          use_recall_for(:controller) || return
+          use_recall_for(:action) || return
           use_recall_for(:id)
         end
 
diff --git a/actionpack/test/controller/render_test.rb b/actionpack/test/controller/render_test.rb
index bf83131189..399c7489b7 100644
--- a/actionpack/test/controller/render_test.rb
+++ b/actionpack/test/controller/render_test.rb
@@ -226,7 +226,7 @@ class TestController < ActionController::Base
   end
 
   def head_and_return
-    head :ok and return
+    head(:ok) && return
     raise "should not reach this line"
   end
 
diff --git a/actionpack/test/controller/routing_test.rb b/actionpack/test/controller/routing_test.rb
index d1cc0f7d68..7be2ad2b28 100644
--- a/actionpack/test/controller/routing_test.rb
+++ b/actionpack/test/controller/routing_test.rb
@@ -211,7 +211,7 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
   def test_class_and_lambda_constraints
     subdomain = Class.new {
       def matches?(request)
-        request.subdomain.present? and request.subdomain != "clients"
+        request.subdomain.present? && request.subdomain != "clients"
       end
     }
 
@@ -229,7 +229,7 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
   def test_lambda_constraints
     rs.draw do
       get "/", constraints: lambda { |req|
-        req.subdomain.present? and req.subdomain != "clients" },
+        req.subdomain.present? && req.subdomain != "clients" },
                  to: lambda { |env| [200, {}, %w{default}] }
 
       get "/", constraints: lambda { |req|
diff --git a/actionpack/test/dispatch/routing_test.rb b/actionpack/test/dispatch/routing_test.rb
index 0938460632..eec34dba66 100644
--- a/actionpack/test/dispatch/routing_test.rb
+++ b/actionpack/test/dispatch/routing_test.rb
@@ -3672,12 +3672,12 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
   def test_multiple_roots
     draw do
       namespace :foo do
-        root "pages#index", constraints: { host: 'www.example.com' }
-        root "admin/pages#index", constraints: { host: 'admin.example.com' }
+        root "pages#index", constraints: { host: "www.example.com" }
+        root "admin/pages#index", constraints: { host: "admin.example.com" }
       end
 
-      root "pages#index", constraints: { host: 'www.example.com' }
-      root "admin/pages#index", constraints: { host: 'admin.example.com' }
+      root "pages#index", constraints: { host: "www.example.com" }
+      root "admin/pages#index", constraints: { host: "admin.example.com" }
     end
 
     get "http://www.example.com/foo"
diff --git a/actionview/Rakefile b/actionview/Rakefile
index f9a7112ade..6c3fc59b0a 100644
--- a/actionview/Rakefile
+++ b/actionview/Rakefile
@@ -14,7 +14,7 @@ namespace :test do
   task :isolated do
     Dir.glob("test/{actionpack,activerecord,template}/**/*_test.rb").all? do |file|
       sh(Gem.ruby, "-w", "-Ilib:test", file)
-    end or raise "Failures"
+    end || raise("Failures")
   end
 
   Rake::TestTask.new(:template) do |t|
diff --git a/actionview/lib/action_view/helpers/capture_helper.rb b/actionview/lib/action_view/helpers/capture_helper.rb
index 5b569b5923..719592b5c5 100644
--- a/actionview/lib/action_view/helpers/capture_helper.rb
+++ b/actionview/lib/action_view/helpers/capture_helper.rb
@@ -37,7 +37,7 @@ module ActionView
       def capture(*args)
         value = nil
         buffer = with_output_buffer { value = yield(*args) }
-        if string = buffer.presence || value and string.is_a?(String)
+        if (string = buffer.presence || value) && string.is_a?(String)
           ERB::Util.html_escape string
         end
       end
diff --git a/actionview/lib/action_view/helpers/form_helper.rb b/actionview/lib/action_view/helpers/form_helper.rb
index b82dff1c17..124a14f1d9 100644
--- a/actionview/lib/action_view/helpers/form_helper.rb
+++ b/actionview/lib/action_view/helpers/form_helper.rb
@@ -1287,7 +1287,7 @@ module ActionView
         @object_name, @object, @template, @options = object_name, object, template, options
         @default_options = @options ? @options.slice(:index, :namespace) : {}
         if @object_name.to_s.match(/\[\]$/)
-          if object ||= @template.instance_variable_get("@#{Regexp.last_match.pre_match}") and object.respond_to?(:to_param)
+          if (object ||= @template.instance_variable_get("@#{Regexp.last_match.pre_match}")) && object.respond_to?(:to_param)
             @auto_index = object.to_param
           else
             raise ArgumentError, "object[] naming but object param and @object var don't exist or don't respond to to_param: #{object.inspect}"
diff --git a/actionview/test/template/tag_helper_test.rb b/actionview/test/template/tag_helper_test.rb
index 278c3e855f..f1e5946e14 100644
--- a/actionview/test/template/tag_helper_test.rb
+++ b/actionview/test/template/tag_helper_test.rb
@@ -284,12 +284,12 @@ class TagHelperTest < ActionView::TestCase
 
   def test_tag_does_not_honor_html_safe_double_quotes_as_attributes
     assert_dom_equal '<p title="&quot;">content</p>',
-      content_tag('p', "content", title: '"'.html_safe)
+      content_tag("p", "content", title: '"'.html_safe)
   end
 
   def test_data_tag_does_not_honor_html_safe_double_quotes_as_attributes
     assert_dom_equal '<p data-title="&quot;">content</p>',
-      content_tag('p', "content", data: { title: '"'.html_safe })
+      content_tag("p", "content", data: { title: '"'.html_safe })
   end
 
   def test_skip_invalid_escaped_attributes
diff --git a/activejob/Rakefile b/activejob/Rakefile
index da153c8a49..3953116061 100644
--- a/activejob/Rakefile
+++ b/activejob/Rakefile
@@ -46,7 +46,7 @@ namespace :test do
         dir = File.dirname(__FILE__)
         Dir.glob("#{dir}/test/cases/**/*_test.rb").all? do |file|
           sh(Gem.ruby, "-w", "-I#{dir}/lib", "-I#{dir}/test", file)
-        end or raise "Failures"
+        end || raise("Failures")
       end
     end
 
diff --git a/activejob/lib/active_job/arguments.rb b/activejob/lib/active_job/arguments.rb
index d94b015014..41ce5f863b 100644
--- a/activejob/lib/active_job/arguments.rb
+++ b/activejob/lib/active_job/arguments.rb
@@ -104,7 +104,7 @@ module ActiveJob
       end
 
       def serialized_global_id?(hash)
-        hash.size == 1 and hash.include?(GLOBALID_KEY)
+        hash.size == 1 && hash.include?(GLOBALID_KEY)
       end
 
       def deserialize_global_id(hash)
diff --git a/activejob/test/cases/exceptions_test.rb b/activejob/test/cases/exceptions_test.rb
index 9ee1dbfa0a..dbe55f7430 100644
--- a/activejob/test/cases/exceptions_test.rb
+++ b/activejob/test/cases/exceptions_test.rb
@@ -58,7 +58,7 @@ class ExceptionsTest < ActiveJob::TestCase
 
   test "custom handling of job that exceeds retry attempts" do
     perform_enqueued_jobs do
-      RetryJob.perform_later 'CustomCatchError', 6
+      RetryJob.perform_later "CustomCatchError", 6
       assert_equal "Dealt with a job that failed to retry in a custom way after 6 attempts", JobBuffer.last_value
     end
   end
diff --git a/activemodel/Rakefile b/activemodel/Rakefile
index d62c7b46c8..c7f97a4258 100644
--- a/activemodel/Rakefile
+++ b/activemodel/Rakefile
@@ -18,6 +18,6 @@ namespace :test do
   task :isolated do
     Dir.glob("#{dir}/test/**/*_test.rb").all? do |file|
       sh(Gem.ruby, "-w", "-I#{dir}/lib", "-I#{dir}/test", file)
-    end or raise "Failures"
+    end || raise("Failures")
   end
 end
diff --git a/activerecord/Rakefile b/activerecord/Rakefile
index 543ab2eaba..e077d345d6 100644
--- a/activerecord/Rakefile
+++ b/activerecord/Rakefile
@@ -67,7 +67,7 @@ end
           |x| x.include?("/adapters/")
         } + Dir["test/cases/adapters/#{adapter_short}/**/*_test.rb"]).all? do |file|
           sh(Gem.ruby, "-w" ,"-Itest", file)
-        end or raise "Failures"
+        end || raise("Failures")
       end
     end
   end
diff --git a/activerecord/lib/active_record/associations/has_many_association.rb b/activerecord/lib/active_record/associations/has_many_association.rb
index 6720578b2c..d1d0cc4c49 100644
--- a/activerecord/lib/active_record/associations/has_many_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_association.rb
@@ -80,7 +80,7 @@ module ActiveRecord
           # If there's nothing in the database and @target has no new records
           # we are certain the current target is an empty array. This is a
           # documented side-effect of the method that may avoid an extra SELECT.
-          @target ||= [] and loaded! if count == 0
+          (@target ||= []) && loaded! if count == 0
 
           [association_scope.limit_value, count].compact.min
         end
diff --git a/activerecord/lib/active_record/associations/join_dependency.rb b/activerecord/lib/active_record/associations/join_dependency.rb
index 02f0721bed..c26c469c1e 100644
--- a/activerecord/lib/active_record/associations/join_dependency.rb
+++ b/activerecord/lib/active_record/associations/join_dependency.rb
@@ -228,8 +228,8 @@ module ActiveRecord
         end
 
         def find_reflection(klass, name)
-          klass._reflect_on_association(name) or
-            raise ConfigurationError, "Can't join '#{ klass.name }' to association named '#{ name }'; perhaps you misspelled it?"
+          klass._reflect_on_association(name) ||
+            raise(ConfigurationError, "Can't join '#{klass.name}' to association named '#{name}'; perhaps you misspelled it?")
         end
 
         def build(associations, base_klass)
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
index 45d782e45e..0bd5ec4b26 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -970,8 +970,8 @@ module ActiveRecord
       end
 
       def foreign_key_for!(from_table, options_or_to_table = {}) # :nodoc:
-        foreign_key_for(from_table, options_or_to_table) or \
-          raise ArgumentError, "Table '#{from_table}' has no foreign key for #{options_or_to_table}"
+        foreign_key_for(from_table, options_or_to_table) || \
+          raise(ArgumentError, "Table '#{from_table}' has no foreign key for #{options_or_to_table}")
       end
 
       def foreign_key_column_for(table_name) # :nodoc:
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
index 696f2cd703..6f5d46b406 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
@@ -360,7 +360,7 @@ module ActiveRecord
 
         # Resets the sequence of a table's primary key to the maximum value.
         def reset_pk_sequence!(table, pk = nil, sequence = nil) #:nodoc:
-          unless pk and sequence
+          unless pk && sequence
             default_pk, default_sequence = pk_and_sequence_for(table)
 
             pk ||= default_pk
@@ -403,7 +403,7 @@ module ActiveRecord
               AND dep.refobjid      = '#{quote_table_name(table)}'::regclass
           end_sql
 
-          if result.nil? or result.empty?
+          if result.nil? || result.empty?
             result = query(<<-end_sql, "SCHEMA")[0]
               SELECT attr.attname, nsp.nspname,
                 CASE
diff --git a/activerecord/lib/active_record/connection_handling.rb b/activerecord/lib/active_record/connection_handling.rb
index b4cd6cdd38..2ede92feff 100644
--- a/activerecord/lib/active_record/connection_handling.rb
+++ b/activerecord/lib/active_record/connection_handling.rb
@@ -109,7 +109,7 @@ module ActiveRecord
     end
 
     def connection_pool
-      connection_handler.retrieve_connection_pool(connection_specification_name) or raise ConnectionNotEstablished
+      connection_handler.retrieve_connection_pool(connection_specification_name) || raise(ConnectionNotEstablished)
     end
 
     def retrieve_connection
diff --git a/activerecord/lib/active_record/core.rb b/activerecord/lib/active_record/core.rb
index 4628d7fb16..3465b68ac6 100644
--- a/activerecord/lib/active_record/core.rb
+++ b/activerecord/lib/active_record/core.rb
@@ -229,7 +229,7 @@ module ActiveRecord
       end
 
       def find_by!(*args) # :nodoc:
-        find_by(*args) or raise RecordNotFound.new("Couldn't find #{name}", name)
+        find_by(*args) || raise(RecordNotFound.new("Couldn't find #{name}", name))
       end
 
       def initialize_generated_modules # :nodoc:
diff --git a/activerecord/test/cases/migration/columns_test.rb b/activerecord/test/cases/migration/columns_test.rb
index 70d40ed87a..870a7f4fa7 100644
--- a/activerecord/test/cases/migration/columns_test.rb
+++ b/activerecord/test/cases/migration/columns_test.rb
@@ -192,8 +192,8 @@ module ActiveRecord
 
         new_columns = connection.columns(TestModel.table_name)
 
-        assert_not new_columns.find { |c| c.name == "age" and c.type == :integer }
-        assert new_columns.find { |c| c.name == "age" and c.type == :string }
+        assert_not new_columns.find { |c| c.name == "age" && c.type == :integer }
+        assert new_columns.find { |c| c.name == "age" && c.type == :string }
 
         old_columns = connection.columns(TestModel.table_name)
         assert old_columns.find { |c|
@@ -206,11 +206,11 @@ module ActiveRecord
 
         assert_not new_columns.find { |c|
           default = connection.lookup_cast_type_from_column(c).deserialize(c.default)
-          c.name == "approved" and c.type == :boolean and default == true
+          c.name == "approved" && c.type == :boolean && default == true
         }
         assert new_columns.find { |c|
           default = connection.lookup_cast_type_from_column(c).deserialize(c.default)
-          c.name == "approved" and c.type == :boolean and default == false
+          c.name == "approved" && c.type == :boolean && default == false
         }
         change_column :test_models, :approved, :boolean, default: true
       end
diff --git a/activesupport/Rakefile b/activesupport/Rakefile
index 54d7a5c6f3..2e1c50cc3d 100644
--- a/activesupport/Rakefile
+++ b/activesupport/Rakefile
@@ -16,6 +16,6 @@ namespace :test do
   task :isolated do
     Dir.glob("test/**/*_test.rb").all? do |file|
       sh(Gem.ruby, "-w", "-Ilib:test", file)
-    end or raise "Failures"
+    end || raise("Failures")
   end
 end
diff --git a/activesupport/bin/generate_tables b/activesupport/bin/generate_tables
index 06dcff4e87..ef220e0329 100755
--- a/activesupport/bin/generate_tables
+++ b/activesupport/bin/generate_tables
@@ -84,7 +84,7 @@ module ActiveSupport
 
         def create_composition_map
           @ucd.codepoints.each do |_, cp|
-            if !cp.nil? and cp.combining_class == 0 and cp.decomp_type.nil? and !cp.decomp_mapping.nil? and cp.decomp_mapping.length == 2 and @ucd.codepoints[cp.decomp_mapping[0]].combining_class == 0 and !@ucd.composition_exclusion.include?(cp.code)
+            if !cp.nil? && cp.combining_class == 0 && cp.decomp_type.nil? && !cp.decomp_mapping.nil? && cp.decomp_mapping.length == 2 && @ucd.codepoints[cp.decomp_mapping[0]].combining_class == 0 && !@ucd.composition_exclusion.include?(cp.code)
               @ucd.composition_map[cp.decomp_mapping[0]] ||= {}
               @ucd.composition_map[cp.decomp_mapping[0]][cp.decomp_mapping[1]] = cp.code
             end
diff --git a/activesupport/lib/active_support/dependencies.rb b/activesupport/lib/active_support/dependencies.rb
index 158bb402bd..216d52164e 100644
--- a/activesupport/lib/active_support/dependencies.rb
+++ b/activesupport/lib/active_support/dependencies.rb
@@ -371,7 +371,7 @@ module ActiveSupport #:nodoc:
             load_args = ["#{file_name}.rb"]
             load_args << const_path unless const_path.nil?
 
-            if !warnings_on_first_load or history.include?(expanded)
+            if !warnings_on_first_load || history.include?(expanded)
               result = load_file(*load_args)
             else
               enable_warnings { result = load_file(*load_args) }
diff --git a/activesupport/lib/active_support/multibyte/unicode.rb b/activesupport/lib/active_support/multibyte/unicode.rb
index ee657080b2..2159abef14 100644
--- a/activesupport/lib/active_support/multibyte/unicode.rb
+++ b/activesupport/lib/active_support/multibyte/unicode.rb
@@ -89,25 +89,25 @@ module ActiveSupport
 
           should_break =
             # GB3. CR X LF
-            if previous == database.boundary[:cr] and current == database.boundary[:lf]
+            if previous == database.boundary[:cr] && current == database.boundary[:lf]
               false
             # GB4. (Control|CR|LF) ÷
-            elsif previous and in_char_class?(previous, [:control,:cr,:lf])
+            elsif previous && in_char_class?(previous, [:control,:cr,:lf])
               true
             # GB5. ÷ (Control|CR|LF)
             elsif in_char_class?(current, [:control,:cr,:lf])
               true
             # GB6. L X (L|V|LV|LVT)
-            elsif database.boundary[:l] === previous and in_char_class?(current, [:l,:v,:lv,:lvt])
+            elsif database.boundary[:l] === previous && in_char_class?(current, [:l,:v,:lv,:lvt])
               false
             # GB7. (LV|V) X (V|T)
-            elsif in_char_class?(previous, [:lv,:v]) and in_char_class?(current, [:v,:t])
+            elsif in_char_class?(previous, [:lv,:v]) && in_char_class?(current, [:v,:t])
               false
             # GB8. (LVT|T) X (T)
-            elsif in_char_class?(previous, [:lvt,:t]) and database.boundary[:t] === current
+            elsif in_char_class?(previous, [:lvt,:t]) && database.boundary[:t] === current
               false
             # GB8a. Regional_Indicator X Regional_Indicator
-            elsif database.boundary[:regional_indicator] === previous and database.boundary[:regional_indicator] === current
+            elsif database.boundary[:regional_indicator] === previous && database.boundary[:regional_indicator] === current
               false
             # GB9. X Extend
             elsif database.boundary[:extend] === current
@@ -158,7 +158,7 @@ module ActiveSupport
       def decompose(type, codepoints)
         codepoints.inject([]) do |decomposed, cp|
           # if it's a hangul syllable starter character
-          if HANGUL_SBASE <= cp and cp < HANGUL_SLAST
+          if HANGUL_SBASE <= cp && cp < HANGUL_SLAST
             sindex = cp - HANGUL_SBASE
             ncp = [] # new codepoints
             ncp << HANGUL_LBASE + sindex / HANGUL_NCOUNT
@@ -167,7 +167,7 @@ module ActiveSupport
             ncp << (HANGUL_TBASE + tindex) unless tindex == 0
             decomposed.concat ncp
           # if the codepoint is decomposable in with the current decomposition type
-          elsif (ncp = database.codepoints[cp].decomp_mapping) and (!database.codepoints[cp].decomp_type || type == :compatibility)
+          elsif (ncp = database.codepoints[cp].decomp_mapping) && (!database.codepoints[cp].decomp_type || type == :compatibility)
             decomposed.concat decompose(type, ncp.dup)
           else
             decomposed << cp
@@ -186,11 +186,11 @@ module ActiveSupport
           pos += 1
           lindex = starter_char - HANGUL_LBASE
           # -- Hangul
-          if 0 <= lindex and lindex < HANGUL_LCOUNT
+          if 0 <= lindex && lindex < HANGUL_LCOUNT
             vindex = codepoints[starter_pos+1] - HANGUL_VBASE rescue vindex = -1
-            if 0 <= vindex and vindex < HANGUL_VCOUNT
+            if 0 <= vindex && vindex < HANGUL_VCOUNT
               tindex = codepoints[starter_pos+2] - HANGUL_TBASE rescue tindex = -1
-              if 0 <= tindex and tindex < HANGUL_TCOUNT
+              if 0 <= tindex && tindex < HANGUL_TCOUNT
                 j = starter_pos + 2
                 eoa -= 2
               else
@@ -392,7 +392,7 @@ module ActiveSupport
           database.codepoints
           string.each_codepoint.map do |codepoint|
             cp = database.codepoints[codepoint]
-            if cp and (ncp = cp.send(mapping)) and ncp > 0
+            if cp && (ncp = cp.send(mapping)) && ncp > 0
               ncp
             else
               codepoint
diff --git a/activesupport/lib/active_support/notifications/fanout.rb b/activesupport/lib/active_support/notifications/fanout.rb
index 055ff6e211..9da115f552 100644
--- a/activesupport/lib/active_support/notifications/fanout.rb
+++ b/activesupport/lib/active_support/notifications/fanout.rb
@@ -68,7 +68,7 @@ module ActiveSupport
 
       module Subscribers # :nodoc:
         def self.new(pattern, listener)
-          if listener.respond_to?(:start) and listener.respond_to?(:finish)
+          if listener.respond_to?(:start) && listener.respond_to?(:finish)
             subscriber = Evented.new pattern, listener
           else
             subscriber = Timed.new pattern, listener
diff --git a/activesupport/test/multibyte_grapheme_break_conformance_test.rb b/activesupport/test/multibyte_grapheme_break_conformance_test.rb
index 5dc42df08d..04a7d290d9 100644
--- a/activesupport/test/multibyte_grapheme_break_conformance_test.rb
+++ b/activesupport/test/multibyte_grapheme_break_conformance_test.rb
@@ -33,7 +33,7 @@ class MultibyteGraphemeBreakConformanceTest < ActiveSupport::TestCase
       lines = 0
       max_test_lines = 0 # Don't limit below 21, because that's the header of the testfile
       File.open(File.join(CACHE_DIR, UNIDATA_FILE), "r") do | f |
-        until f.eof? || (max_test_lines > 21 and lines > max_test_lines)
+        until f.eof? || (max_test_lines > 21 && lines > max_test_lines)
           lines += 1
           line = f.gets.chomp!
           next if line.empty? || line.start_with?("#")
diff --git a/activesupport/test/multibyte_normalization_conformance_test.rb b/activesupport/test/multibyte_normalization_conformance_test.rb
index 716e6487aa..e013bd578f 100644
--- a/activesupport/test/multibyte_normalization_conformance_test.rb
+++ b/activesupport/test/multibyte_normalization_conformance_test.rb
@@ -88,7 +88,7 @@ class MultibyteNormalizationConformanceTest < ActiveSupport::TestCase
       lines = 0
       max_test_lines = 0 # Don't limit below 38, because that's the header of the testfile
       File.open(File.join(CACHE_DIR, UNIDATA_FILE), "r") do | f |
-        until f.eof? || (max_test_lines > 38 and lines > max_test_lines)
+        until f.eof? || (max_test_lines > 38 && lines > max_test_lines)
           lines += 1
           line = f.gets.chomp!
           next if line.empty? || line.start_with?("#")
diff --git a/railties/lib/rails/app_loader.rb b/railties/lib/rails/app_loader.rb
index 107e47de55..525d5f0161 100644
--- a/railties/lib/rails/app_loader.rb
+++ b/railties/lib/rails/app_loader.rb
@@ -50,7 +50,7 @@ EOS
 
         # If we exhaust the search there is no executable, this could be a
         # call to generate a new application, so restore the original cwd.
-        Dir.chdir(original_cwd) and return if Pathname.new(Dir.pwd).root?
+        Dir.chdir(original_cwd) && return if Pathname.new(Dir.pwd).root?
 
         # Otherwise keep moving upwards in search of an executable.
         Dir.chdir("..")
diff --git a/railties/lib/rails/generators/base.rb b/railties/lib/rails/generators/base.rb
index c0e34c20e7..1a0420c769 100644
--- a/railties/lib/rails/generators/base.rb
+++ b/railties/lib/rails/generators/base.rb
@@ -310,9 +310,9 @@ module Rails
 
         # Returns default for the option name given doing a lookup in config.
         def self.default_for_option(config, name, options, default)
-          if generator_name and c = config[generator_name.to_sym] and c.key?(name)
+          if generator_name && (c = config[generator_name.to_sym]) && c.key?(name)
             c[name]
-          elsif base_name and c = config[base_name.to_sym] and c.key?(name)
+          elsif base_name && (c = config[base_name.to_sym]) && c.key?(name)
             c[name]
           elsif config[:rails].key?(name)
             config[:rails][name]
diff --git a/railties/test/json_params_parsing_test.rb b/railties/test/json_params_parsing_test.rb
index 104664c1ee..7fff3bb465 100644
--- a/railties/test/json_params_parsing_test.rb
+++ b/railties/test/json_params_parsing_test.rb
@@ -6,7 +6,7 @@ class JsonParamsParsingTest < ActionDispatch::IntegrationTest
   def test_prevent_null_query
     # Make sure we have data to find
     klass = Class.new(ActiveRecord::Base) do
-      def self.name; 'Foo'; end
+      def self.name; "Foo"; end
       establish_connection adapter: "sqlite3", database: ":memory:"
       connection.create_table "foos" do |t|
         t.string :title
@@ -26,24 +26,24 @@ class JsonParamsParsingTest < ActionDispatch::IntegrationTest
       end
     }
 
-    assert_nil app.call(make_env({ 't' => nil }))
-    assert_nil app.call(make_env({ 't' => [nil] }))
+    assert_nil app.call(make_env("t" => nil))
+    assert_nil app.call(make_env("t" => [nil]))
 
     [[[nil]], [[[nil]]]].each do |data|
-      assert_nil app.call(make_env({ 't' => data }))
+      assert_nil app.call(make_env("t" => data))
     end
   ensure
     klass.connection.drop_table("foos")
   end
 
   private
-    def make_env json
+    def make_env(json)
       data = JSON.dump json
       content_length = data.length
       {
-        'CONTENT_LENGTH' => content_length,
-        'CONTENT_TYPE'   => 'application/json',
-        'rack.input'     => StringIO.new(data)
+        "CONTENT_LENGTH" => content_length,
+        "CONTENT_TYPE"   => "application/json",
+        "rack.input"     => StringIO.new(data)
       }
     end
 end
diff --git a/tools/profile b/tools/profile
index 124ed0f4be..f7d91e51cf 100755
--- a/tools/profile
+++ b/tools/profile
@@ -72,7 +72,7 @@ module CodeTools
         fail Error.new("#{path} is a directory") if File.directory?(path)
         ruby_extension = File.extname(path) == ".rb"
         ruby_executable = File.open(path, "rb") { |f| f.readline } =~ [/\A#!.*ruby/]
-        fail Error.new("Not a ruby file") unless ruby_extension or ruby_executable
+        fail Error.new("Not a ruby file") unless ruby_extension || ruby_executable
       end
 
       module RequireProfiler