Merge branch 'master' into feature/reselect-method

18 files changed, 404 insertions, 66 deletions

diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index fd96c46814..b796df26aa 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,3 +1,16 @@
+*   Add `ActiveSupport::ParameterFilter`.
+
+    *Yoshiyuki Kinjo*
+
+*   Rename `Module#parent`, `Module#parents`, and `Module#parent_name` to
+    `module_parent`, `module_parents`, and `module_parent_name`.
+
+    *Gannon McGibbon*
+
+*   Deprecate the use of `LoggerSilence` in favor of `ActiveSupport::LoggerSilence`
+
+    *Edouard Chin*
+
 *   Deprecate using negative limits in `String#first` and `String#last`.
 
     *Gannon McGibbon*, *Eric Turner*
diff --git a/activesupport/lib/active_support/cache.rb b/activesupport/lib/active_support/cache.rb
index a5d0c52b13..2be79d86dd 100644
--- a/activesupport/lib/active_support/cache.rb
+++ b/activesupport/lib/active_support/cache.rb
@@ -596,9 +596,13 @@ module ActiveSupport
         # Merges the default options with ones specific to a method call.
         def merged_options(call_options)
           if call_options
-            options.merge(call_options)
+            if options.empty?
+              call_options
+            else
+              options.merge(call_options)
+            end
           else
-            options.dup
+            options
           end
         end
 
@@ -643,7 +647,7 @@ module ActiveSupport
             if key.size > 1
               key = key.collect { |element| expanded_key(element) }
             else
-              key = key.first
+              key = expanded_key(key.first)
             end
           when Hash
             key = key.sort_by { |k, _| k.to_s }.collect { |k, v| "#{k}=#{v}" }
diff --git a/activesupport/lib/active_support/configurable.rb b/activesupport/lib/active_support/configurable.rb
index 2610114d8f..6159e45230 100644
--- a/activesupport/lib/active_support/configurable.rb
+++ b/activesupport/lib/active_support/configurable.rb
@@ -105,7 +105,7 @@ module ActiveSupport
       #   end
       #
       #   User.hair_colors # => [:brown, :black, :blonde, :red]
-      def config_accessor(*names)
+      def config_accessor(*names) #:doc:
         options = names.extract_options!
 
         names.each do |name|
diff --git a/activesupport/lib/active_support/core_ext/module/introspection.rb b/activesupport/lib/active_support/core_ext/module/introspection.rb
index c5bb598bd1..9b6df40596 100644
--- a/activesupport/lib/active_support/core_ext/module/introspection.rb
+++ b/activesupport/lib/active_support/core_ext/module/introspection.rb
@@ -5,8 +5,8 @@ require "active_support/inflector"
 class Module
   # Returns the name of the module containing this one.
   #
-  #   M::N.parent_name # => "M"
-  def parent_name
+  #   M::N.module_parent_name # => "M"
+  def module_parent_name
     if defined?(@parent_name)
       @parent_name
     else
@@ -16,6 +16,14 @@ class Module
     end
   end
 
+  def parent_name
+    ActiveSupport::Deprecation.warn(<<-MSG.squish)
+      `Module#parent_name` has been renamed to `module_parent_name`.
+      `parent_name` is deprecated and will be removed in Rails 6.1.
+    MSG
+    module_parent_name
+  end
+
   # Returns the module which contains this one according to its name.
   #
   #   module M
@@ -24,15 +32,23 @@ class Module
   #   end
   #   X = M::N
   #
-  #   M::N.parent # => M
-  #   X.parent    # => M
+  #   M::N.module_parent # => M
+  #   X.module_parent    # => M
   #
   # The parent of top-level and anonymous modules is Object.
   #
-  #   M.parent          # => Object
-  #   Module.new.parent # => Object
+  #   M.module_parent          # => Object
+  #   Module.new.module_parent # => Object
+  def module_parent
+    module_parent_name ? ActiveSupport::Inflector.constantize(module_parent_name) : Object
+  end
+
   def parent
-    parent_name ? ActiveSupport::Inflector.constantize(parent_name) : Object
+    ActiveSupport::Deprecation.warn(<<-MSG.squish)
+      `Module#parent` has been renamed to `module_parent`.
+      `parent` is deprecated and will be removed in Rails 6.1.
+    MSG
+    module_parent
   end
 
   # Returns all the parents of this module according to its name, ordered from
@@ -44,13 +60,13 @@ class Module
   #   end
   #   X = M::N
   #
-  #   M.parents    # => [Object]
-  #   M::N.parents # => [M, Object]
-  #   X.parents    # => [M, Object]
-  def parents
+  #   M.module_parents    # => [Object]
+  #   M::N.module_parents # => [M, Object]
+  #   X.module_parents    # => [M, Object]
+  def module_parents
     parents = []
-    if parent_name
-      parts = parent_name.split("::")
+    if module_parent_name
+      parts = module_parent_name.split("::")
       until parts.empty?
         parents << ActiveSupport::Inflector.constantize(parts * "::")
         parts.pop
@@ -59,4 +75,12 @@ class Module
     parents << Object unless parents.include? Object
     parents
   end
+
+  def parents
+    ActiveSupport::Deprecation.warn(<<-MSG.squish)
+      `Module#parents` has been renamed to `module_parents`.
+      `parents` is deprecated and will be removed in Rails 6.1.
+    MSG
+    module_parents
+  end
 end
diff --git a/activesupport/lib/active_support/core_ext/object/try.rb b/activesupport/lib/active_support/core_ext/object/try.rb
index aa6896af32..ef8a1f476d 100644
--- a/activesupport/lib/active_support/core_ext/object/try.rb
+++ b/activesupport/lib/active_support/core_ext/object/try.rb
@@ -143,14 +143,14 @@ class NilClass
   #
   # With +try+
   #   @person.try(:children).try(:first).try(:name)
-  def try(*args)
+  def try(method_name = nil, *args)
     nil
   end
 
   # Calling +try!+ on +nil+ always returns +nil+.
   #
   #   nil.try!(:name) # => nil
-  def try!(*args)
+  def try!(method_name = nil, *args)
     nil
   end
 end
diff --git a/activesupport/lib/active_support/dependencies.rb b/activesupport/lib/active_support/dependencies.rb
index 063d8d1587..66e0bea00e 100644
--- a/activesupport/lib/active_support/dependencies.rb
+++ b/activesupport/lib/active_support/dependencies.rb
@@ -521,8 +521,8 @@ module ActiveSupport #:nodoc:
         end
       elsif mod = autoload_module!(from_mod, const_name, qualified_name, path_suffix)
         return mod
-      elsif (parent = from_mod.parent) && parent != from_mod &&
-            ! from_mod.parents.any? { |p| p.const_defined?(const_name, false) }
+      elsif (parent = from_mod.module_parent) && parent != from_mod &&
+            ! from_mod.module_parents.any? { |p| p.const_defined?(const_name, false) }
         # If our parents do not have a constant named +const_name+ then we are free
         # to attempt to load upwards. If they do have such a constant, then this
         # const_missing must be due to from_mod::const_name, which should not
diff --git a/activesupport/lib/active_support/encrypted_configuration.rb b/activesupport/lib/active_support/encrypted_configuration.rb
index 3c6da10548..cc1d026737 100644
--- a/activesupport/lib/active_support/encrypted_configuration.rb
+++ b/activesupport/lib/active_support/encrypted_configuration.rb
@@ -39,7 +39,7 @@ module ActiveSupport
       end
 
       def deserialize(config)
-        config.present? ? YAML.load(config, content_path) : {}
+        YAML.load(config).presence || {}
       end
   end
 end
diff --git a/activesupport/lib/active_support/logger.rb b/activesupport/lib/active_support/logger.rb
index 8152a182b4..b8555c887b 100644
--- a/activesupport/lib/active_support/logger.rb
+++ b/activesupport/lib/active_support/logger.rb
@@ -6,7 +6,6 @@ require "logger"
 
 module ActiveSupport
   class Logger < ::Logger
-    include ActiveSupport::LoggerThreadSafeLevel
     include LoggerSilence
 
     # Returns true if the logger destination matches one of the sources
@@ -81,20 +80,6 @@ module ActiveSupport
     def initialize(*args)
       super
       @formatter = SimpleFormatter.new
-      after_initialize if respond_to? :after_initialize
-    end
-
-    def add(severity, message = nil, progname = nil, &block)
-      return true if @logdev.nil? || (severity || UNKNOWN) < level
-      super
-    end
-
-    Logger::Severity.constants.each do |severity|
-      class_eval(<<-EOT, __FILE__, __LINE__ + 1)
-        def #{severity.downcase}?                # def debug?
-          Logger::#{severity} >= level           #   DEBUG >= level
-        end                                      # end
-      EOT
     end
 
     # Simple formatter which only displays the message.
diff --git a/activesupport/lib/active_support/logger_silence.rb b/activesupport/lib/active_support/logger_silence.rb
index 4344ca0429..b2444c1e34 100644
--- a/activesupport/lib/active_support/logger_silence.rb
+++ b/activesupport/lib/active_support/logger_silence.rb
@@ -2,27 +2,44 @@
 
 require "active_support/concern"
 require "active_support/core_ext/module/attribute_accessors"
+require "active_support/logger_thread_safe_level"
 
 module LoggerSilence
   extend ActiveSupport::Concern
 
   included do
-    cattr_accessor :silencer, default: true
+    ActiveSupport::Deprecation.warn(
+      "Including LoggerSilence is deprecated and will be removed in Rails 6.1. " \
+      "Please use `ActiveSupport::LoggerSilence` instead"
+    )
+
+    include ActiveSupport::LoggerSilence
   end
+end
+
+module ActiveSupport
+  module LoggerSilence
+    extend ActiveSupport::Concern
+
+    included do
+      cattr_accessor :silencer, default: true
+      include ActiveSupport::LoggerThreadSafeLevel
+    end
 
-  # Silences the logger for the duration of the block.
-  def silence(temporary_level = Logger::ERROR)
-    if silencer
-      begin
-        old_local_level            = local_level
-        self.local_level           = temporary_level
+    # Silences the logger for the duration of the block.
+    def silence(temporary_level = Logger::ERROR)
+      if silencer
+        begin
+          old_local_level            = local_level
+          self.local_level           = temporary_level
 
+          yield self
+        ensure
+          self.local_level = old_local_level
+        end
+      else
         yield self
-      ensure
-        self.local_level = old_local_level
       end
-    else
-      yield self
     end
   end
 end
diff --git a/activesupport/lib/active_support/logger_thread_safe_level.rb b/activesupport/lib/active_support/logger_thread_safe_level.rb
index 22ab4cc28c..f16c90cfc6 100644
--- a/activesupport/lib/active_support/logger_thread_safe_level.rb
+++ b/activesupport/lib/active_support/logger_thread_safe_level.rb
@@ -1,14 +1,30 @@
 # frozen_string_literal: true
 
 require "active_support/concern"
+require "active_support/core_ext/module/attribute_accessors"
 require "concurrent"
 
 module ActiveSupport
   module LoggerThreadSafeLevel # :nodoc:
     extend ActiveSupport::Concern
 
+    included do
+      cattr_accessor :local_levels, default: Concurrent::Map.new(initial_capacity: 2), instance_accessor: false
+    end
+
+    Logger::Severity.constants.each do |severity|
+      class_eval(<<-EOT, __FILE__, __LINE__ + 1)
+        def #{severity.downcase}?                # def debug?
+          Logger::#{severity} >= level           #   DEBUG >= level
+        end                                      # end
+      EOT
+    end
+
     def after_initialize
-      @local_levels = Concurrent::Map.new(initial_capacity: 2)
+      ActiveSupport::Deprecation.warn(
+        "Logger don't need to call #after_initialize directly anymore. It will be deprecated without replacement in " \
+        "Rails 6.1."
+      )
     end
 
     def local_log_id
@@ -16,19 +32,24 @@ module ActiveSupport
     end
 
     def local_level
-      @local_levels[local_log_id]
+      self.class.local_levels[local_log_id]
     end
 
     def local_level=(level)
       if level
-        @local_levels[local_log_id] = level
+        self.class.local_levels[local_log_id] = level
       else
-        @local_levels.delete(local_log_id)
+        self.class.local_levels.delete(local_log_id)
       end
     end
 
     def level
       local_level || super
     end
+
+    def add(severity, message = nil, progname = nil, &block) # :nodoc:
+      return true if @logdev.nil? || (severity || UNKNOWN) < level
+      super
+    end
   end
 end
diff --git a/activesupport/lib/active_support/notifications.rb b/activesupport/lib/active_support/notifications.rb
index 6207de8094..2d8b9c5d86 100644
--- a/activesupport/lib/active_support/notifications.rb
+++ b/activesupport/lib/active_support/notifications.rb
@@ -34,7 +34,7 @@ module ActiveSupport
   #     name    # => String, name of the event (such as 'render' from above)
   #     start   # => Time, when the instrumented block started execution
   #     finish  # => Time, when the instrumented block ended execution
-  #     id      # => String, unique ID for this notification
+  #     id      # => String, unique ID for the instrumenter that fired the event
   #     payload # => Hash, the payload
   #   end
   #
@@ -59,7 +59,7 @@ module ActiveSupport
   #   event.payload   # => { extra: :information }
   #
   # The block in the <tt>subscribe</tt> call gets the name of the event, start
-  # timestamp, end timestamp, a string with a unique identifier for that event
+  # timestamp, end timestamp, a string with a unique identifier for that event's instrumenter
   # (something like "535801666f04d0298cd6"), and a hash with the payload, in
   # that order.
   #
diff --git a/activesupport/lib/active_support/parameter_filter.rb b/activesupport/lib/active_support/parameter_filter.rb
new file mode 100644
index 0000000000..59945e9daa
--- /dev/null
+++ b/activesupport/lib/active_support/parameter_filter.rb
@@ -0,0 +1,106 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/object/duplicable"
+require "active_support/core_ext/array/extract"
+
+module ActiveSupport
+  # +ParameterFilter+ allows you to specify keys for sensitive data from
+  # hash-like object and replace corresponding value. Filtering only certain
+  # sub-keys from a hash is possible by using the dot notation:
+  # 'credit_card.number'. If a proc is given, each key and value of a hash and
+  # all sub-hashes are passed to it, where the value or the key can be replaced
+  # using String#replace or similar methods.
+  #
+  #   ActiveSupport::ParameterFilter.new([:password])
+  #   => replaces the value to all keys matching /password/i with "[FILTERED]"
+  #
+  #   ActiveSupport::ParameterFilter.new([:foo, "bar"])
+  #   => replaces the value to all keys matching /foo|bar/i with "[FILTERED]"
+  #
+  #   ActiveSupport::ParameterFilter.new(["credit_card.code"])
+  #   => replaces { credit_card: {code: "xxxx"} } with "[FILTERED]", does not
+  #   change { file: { code: "xxxx"} }
+  #
+  #   ActiveSupport::ParameterFilter.new([-> (k, v) do
+  #     v.reverse! if k =~ /secret/i
+  #   end])
+  #   => reverses the value to all keys matching /secret/i
+  class ParameterFilter
+    FILTERED = "[FILTERED]" # :nodoc:
+
+    def initialize(filters = [])
+      @filters = filters
+    end
+
+    def filter(params)
+      compiled_filter.call(params)
+    end
+
+  private
+
+    def compiled_filter
+      @compiled_filter ||= CompiledFilter.compile(@filters)
+    end
+
+    class CompiledFilter # :nodoc:
+      def self.compile(filters)
+        return lambda { |params| params.dup } if filters.empty?
+
+        strings, regexps, blocks = [], [], []
+
+        filters.each do |item|
+          case item
+          when Proc
+            blocks << item
+          when Regexp
+            regexps << item
+          else
+            strings << Regexp.escape(item.to_s)
+          end
+        end
+
+        deep_regexps = regexps.extract! { |r| r.to_s.include?("\\.") }
+        deep_strings = strings.extract! { |s| s.include?("\\.") }
+
+        regexps << Regexp.new(strings.join("|"), true) unless strings.empty?
+        deep_regexps << Regexp.new(deep_strings.join("|"), true) unless deep_strings.empty?
+
+        new regexps, deep_regexps, blocks
+      end
+
+      attr_reader :regexps, :deep_regexps, :blocks
+
+      def initialize(regexps, deep_regexps, blocks)
+        @regexps = regexps
+        @deep_regexps = deep_regexps.any? ? deep_regexps : nil
+        @blocks = blocks
+      end
+
+      def call(params, parents = [], original_params = params)
+        filtered_params = params.class.new
+
+        params.each do |key, value|
+          parents.push(key) if deep_regexps
+          if regexps.any? { |r| key =~ r }
+            value = FILTERED
+          elsif deep_regexps && (joined = parents.join(".")) && deep_regexps.any? { |r| joined =~ r }
+            value = FILTERED
+          elsif value.is_a?(Hash)
+            value = call(value, parents, original_params)
+          elsif value.is_a?(Array)
+            value = value.map { |v| v.is_a?(Hash) ? call(v, parents, original_params) : v }
+          elsif blocks.any?
+            key = key.dup if key.duplicable?
+            value = value.dup if value.duplicable?
+            blocks.each { |b| b.arity == 2 ? b.call(key, value) : b.call(key, value, original_params) }
+          end
+          parents.pop if deep_regexps
+
+          filtered_params[key] = value
+        end
+
+        filtered_params
+      end
+    end
+  end
+end
diff --git a/activesupport/test/broadcast_logger_test.rb b/activesupport/test/broadcast_logger_test.rb
index 181113e70a..7dfa8a62bd 100644
--- a/activesupport/test/broadcast_logger_test.rb
+++ b/activesupport/test/broadcast_logger_test.rb
@@ -114,7 +114,17 @@ module ActiveSupport
       assert_equal [[::Logger::FATAL, "seen", nil]], log2.adds
     end
 
+    test "Including top constant LoggerSilence is deprecated" do
+      assert_deprecated("Please use `ActiveSupport::LoggerSilence`") do
+        Class.new(CustomLogger) do
+          include ::LoggerSilence
+        end
+      end
+    end
+
     class CustomLogger
+      include ActiveSupport::LoggerSilence
+
       attr_reader :adds, :closed, :chevrons
       attr_accessor :level, :progname, :formatter, :local_level
 
@@ -166,7 +176,6 @@ module ActiveSupport
     end
 
     class FakeLogger < CustomLogger
-      include LoggerSilence
     end
   end
 end
diff --git a/activesupport/test/cache/behaviors/cache_store_behavior.rb b/activesupport/test/cache/behaviors/cache_store_behavior.rb
index 30735eb0eb..9f54b1e7de 100644
--- a/activesupport/test/cache/behaviors/cache_store_behavior.rb
+++ b/activesupport/test/cache/behaviors/cache_store_behavior.rb
@@ -290,6 +290,55 @@ module CacheStoreBehavior
     assert_equal "bar", @cache.read("fu/foo")
   end
 
+  InstanceTest = Struct.new(:name, :id) do
+    def cache_key
+      "#{name}/#{id}"
+    end
+
+    def to_param
+      "hello"
+    end
+  end
+
+  def test_array_with_single_instance_as_cache_key_uses_cache_key_method
+    test_instance_one = InstanceTest.new("test", 1)
+    test_instance_two = InstanceTest.new("test", 2)
+
+    @cache.write([test_instance_one], "one")
+    @cache.write([test_instance_two], "two")
+
+    assert_equal "one", @cache.read([test_instance_one])
+    assert_equal "two", @cache.read([test_instance_two])
+  end
+
+  def test_array_with_multiple_instances_as_cache_key_uses_cache_key_method
+    test_instance_one = InstanceTest.new("test", 1)
+    test_instance_two = InstanceTest.new("test", 2)
+    test_instance_three = InstanceTest.new("test", 3)
+
+    @cache.write([test_instance_one, test_instance_three], "one")
+    @cache.write([test_instance_two, test_instance_three], "two")
+
+    assert_equal "one", @cache.read([test_instance_one, test_instance_three])
+    assert_equal "two", @cache.read([test_instance_two, test_instance_three])
+  end
+
+  def test_format_of_expanded_key_for_single_instance
+    test_instance_one = InstanceTest.new("test", 1)
+
+    expanded_key = @cache.send(:expanded_key, test_instance_one)
+
+    assert_equal expanded_key, test_instance_one.cache_key
+  end
+
+  def test_format_of_expanded_key_for_single_instance_in_array
+    test_instance_one = InstanceTest.new("test", 1)
+
+    expanded_key = @cache.send(:expanded_key, [test_instance_one])
+
+    assert_equal expanded_key, test_instance_one.cache_key
+  end
+
   def test_hash_as_cache_key
     @cache.write({ foo: 1, fu: 2 }, "bar")
     assert_equal "bar", @cache.read("foo=1/fu=2")
diff --git a/activesupport/test/core_ext/module/introspection_test.rb b/activesupport/test/core_ext/module/introspection_test.rb
index 76d3012239..d8409d5e44 100644
--- a/activesupport/test/core_ext/module/introspection_test.rb
+++ b/activesupport/test/core_ext/module/introspection_test.rb
@@ -15,25 +15,43 @@ module ParentA
 end
 
 class IntrospectionTest < ActiveSupport::TestCase
+  def test_module_parent_name
+    assert_equal "ParentA", ParentA::B.module_parent_name
+    assert_equal "ParentA::B", ParentA::B::C.module_parent_name
+    assert_nil ParentA.module_parent_name
+  end
+
+  def test_module_parent_name_when_frozen
+    assert_equal "ParentA", ParentA::FrozenB.module_parent_name
+    assert_equal "ParentA::B", ParentA::B::FrozenC.module_parent_name
+  end
+
   def test_parent_name
-    assert_equal "ParentA", ParentA::B.parent_name
-    assert_equal "ParentA::B", ParentA::B::C.parent_name
-    assert_nil ParentA.parent_name
+    assert_deprecated do
+      assert_equal "ParentA", ParentA::B.parent_name
+    end
   end
 
-  def test_parent_name_when_frozen
-    assert_equal "ParentA", ParentA::FrozenB.parent_name
-    assert_equal "ParentA::B", ParentA::B::FrozenC.parent_name
+  def test_module_parent
+    assert_equal ParentA::B, ParentA::B::C.module_parent
+    assert_equal ParentA, ParentA::B.module_parent
+    assert_equal Object, ParentA.module_parent
   end
 
   def test_parent
-    assert_equal ParentA::B, ParentA::B::C.parent
-    assert_equal ParentA, ParentA::B.parent
-    assert_equal Object, ParentA.parent
+    assert_deprecated do
+      assert_equal ParentA, ParentA::B.parent
+    end
+  end
+
+  def test_module_parents
+    assert_equal [ParentA::B, ParentA, Object], ParentA::B::C.module_parents
+    assert_equal [ParentA, Object], ParentA::B.module_parents
   end
 
   def test_parents
-    assert_equal [ParentA::B, ParentA, Object], ParentA::B::C.parents
-    assert_equal [ParentA, Object], ParentA::B.parents
+    assert_deprecated do
+      assert_equal [ParentA, Object], ParentA::B.parents
+    end
   end
 end
diff --git a/activesupport/test/encrypted_configuration_test.rb b/activesupport/test/encrypted_configuration_test.rb
index 93ccf457de..387d6e1c1f 100644
--- a/activesupport/test/encrypted_configuration_test.rb
+++ b/activesupport/test/encrypted_configuration_test.rb
@@ -42,6 +42,12 @@ class EncryptedConfigurationTest < ActiveSupport::TestCase
     assert @credentials.something[:good]
   end
 
+  test "reading comment-only configuration" do
+    @credentials.write("# comment")
+
+    assert_equal @credentials.config, {}
+  end
+
   test "change configuration by key file" do
     @credentials.write({ something: { good: true } }.to_yaml)
     @credentials.change do |config_file|
diff --git a/activesupport/test/parameter_filter_test.rb b/activesupport/test/parameter_filter_test.rb
new file mode 100644
index 0000000000..3403a3188b
--- /dev/null
+++ b/activesupport/test/parameter_filter_test.rb
@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/core_ext/hash"
+require "active_support/parameter_filter"
+
+class ParameterFilterTest < ActiveSupport::TestCase
+  test "process parameter filter" do
+    test_hashes = [
+    [{ "foo" => "bar" }, { "foo" => "bar" }, %w'food'],
+    [{ "foo" => "bar" }, { "foo" => "[FILTERED]" }, %w'foo'],
+    [{ "foo" => "bar", "bar" => "foo" }, { "foo" => "[FILTERED]", "bar" => "foo" }, %w'foo baz'],
+    [{ "foo" => "bar", "baz" => "foo" }, { "foo" => "[FILTERED]", "baz" => "[FILTERED]" }, %w'foo baz'],
+    [{ "bar" => { "foo" => "bar", "bar" => "foo" } }, { "bar" => { "foo" => "[FILTERED]", "bar" => "foo" } }, %w'fo'],
+    [{ "foo" => { "foo" => "bar", "bar" => "foo" } }, { "foo" => "[FILTERED]" }, %w'f banana'],
+    [{ "deep" => { "cc" => { "code" => "bar", "bar" => "foo" }, "ss" => { "code" => "bar" } } }, { "deep" => { "cc" => { "code" => "[FILTERED]", "bar" => "foo" }, "ss" => { "code" => "bar" } } }, %w'deep.cc.code'],
+    [{ "baz" => [{ "foo" => "baz" }, "1"] }, { "baz" => [{ "foo" => "[FILTERED]" }, "1"] }, [/foo/]]]
+
+    test_hashes.each do |before_filter, after_filter, filter_words|
+      parameter_filter = ActiveSupport::ParameterFilter.new(filter_words)
+      assert_equal after_filter, parameter_filter.filter(before_filter)
+
+      filter_words << "blah"
+      filter_words << lambda { |key, value|
+        value.reverse! if key =~ /bargain/
+      }
+      filter_words << lambda { |key, value, original_params|
+        value.replace("world!") if original_params["barg"]["blah"] == "bar" && key == "hello"
+      }
+
+      parameter_filter = ActiveSupport::ParameterFilter.new(filter_words)
+      before_filter["barg"] = { :bargain => "gain", "blah" => "bar", "bar" => { "bargain" => { "blah" => "foo", "hello" => "world" } } }
+      after_filter["barg"]  = { :bargain => "niag", "blah" => "[FILTERED]", "bar" => { "bargain" => { "blah" => "[FILTERED]", "hello" => "world!" } } }
+
+      assert_equal after_filter, parameter_filter.filter(before_filter)
+    end
+  end
+
+  test "parameter filter should maintain hash with indifferent access" do
+    test_hashes = [
+      [{ "foo" => "bar" }.with_indifferent_access, ["blah"]],
+      [{ "foo" => "bar" }.with_indifferent_access, []]
+    ]
+
+    test_hashes.each do |before_filter, filter_words|
+      parameter_filter = ActiveSupport::ParameterFilter.new(filter_words)
+      assert_instance_of ActiveSupport::HashWithIndifferentAccess,
+                         parameter_filter.filter(before_filter)
+    end
+  end
+end
diff --git a/activesupport/test/silence_logger_test.rb b/activesupport/test/silence_logger_test.rb
new file mode 100644
index 0000000000..bd0c6b7f86
--- /dev/null
+++ b/activesupport/test/silence_logger_test.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "active_support/logger_silence"
+require "logger"
+
+class LoggerSilenceTest < ActiveSupport::TestCase
+  class MyLogger < ::Logger
+    include ActiveSupport::LoggerSilence
+  end
+
+  setup do
+    @io = StringIO.new
+    @logger = MyLogger.new(@io)
+  end
+
+  test "#silence silences the log" do
+    @logger.silence(Logger::ERROR) do
+      @logger.info("Foo")
+    end
+    @io.rewind
+
+    assert_empty @io.read
+  end
+
+  test "#debug? is true when setting the temporary level to Logger::DEBUG" do
+    @logger.level = Logger::INFO
+
+    @logger.silence(Logger::DEBUG) do
+      assert_predicate @logger, :debug?
+    end
+
+    assert_predicate @logger, :info?
+  end
+end