Merge pull request #29540 from kirs/rubocop-frozen-string

Enforce frozen string in Rubocop

114 files changed, 114 insertions, 0 deletions

diff --git a/activesupport/lib/active_support/core_ext/array.rb b/activesupport/lib/active_support/core_ext/array.rb
index e908386a1c..3f58855902 100644
--- a/activesupport/lib/active_support/core_ext/array.rb
+++ b/activesupport/lib/active_support/core_ext/array.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/array/wrap"
 require "active_support/core_ext/array/access"
 require "active_support/core_ext/array/conversions"
diff --git a/activesupport/lib/active_support/core_ext/array/access.rb b/activesupport/lib/active_support/core_ext/array/access.rb
index fca33c9d69..b6e576ad29 100644
--- a/activesupport/lib/active_support/core_ext/array/access.rb
+++ b/activesupport/lib/active_support/core_ext/array/access.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Array
   # Returns the tail of the array from +position+.
   #
diff --git a/activesupport/lib/active_support/core_ext/array/conversions.rb b/activesupport/lib/active_support/core_ext/array/conversions.rb
index cac15e1100..3d00046d02 100644
--- a/activesupport/lib/active_support/core_ext/array/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/array/conversions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/xml_mini"
 require "active_support/core_ext/hash/keys"
 require "active_support/core_ext/string/inflections"
diff --git a/activesupport/lib/active_support/core_ext/array/extract_options.rb b/activesupport/lib/active_support/core_ext/array/extract_options.rb
index 9008a0df2a..8204d42caf 100644
--- a/activesupport/lib/active_support/core_ext/array/extract_options.rb
+++ b/activesupport/lib/active_support/core_ext/array/extract_options.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Hash
   # By default, only instances of Hash itself are extractable.
   # Subclasses of Hash may implement this method and return
diff --git a/activesupport/lib/active_support/core_ext/array/grouping.rb b/activesupport/lib/active_support/core_ext/array/grouping.rb
index 0d798e5c4e..706c576691 100644
--- a/activesupport/lib/active_support/core_ext/array/grouping.rb
+++ b/activesupport/lib/active_support/core_ext/array/grouping.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Array
   # Splits or iterates over the array in groups of size +number+,
   # padding any remaining slots with +fill_with+ unless it is +false+.
diff --git a/activesupport/lib/active_support/core_ext/array/inquiry.rb b/activesupport/lib/active_support/core_ext/array/inquiry.rb
index 66fa5fcd0c..81082f7128 100644
--- a/activesupport/lib/active_support/core_ext/array/inquiry.rb
+++ b/activesupport/lib/active_support/core_ext/array/inquiry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/array_inquirer"
 
 class Array
diff --git a/activesupport/lib/active_support/core_ext/array/prepend_and_append.rb b/activesupport/lib/active_support/core_ext/array/prepend_and_append.rb
index 88a34128c9..2dd1547765 100644
--- a/activesupport/lib/active_support/core_ext/array/prepend_and_append.rb
+++ b/activesupport/lib/active_support/core_ext/array/prepend_and_append.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Array
   # The human way of thinking about adding stuff to the end of a list is with append.
   alias_method :append,  :push unless [].respond_to?(:append)
diff --git a/activesupport/lib/active_support/core_ext/array/wrap.rb b/activesupport/lib/active_support/core_ext/array/wrap.rb
index b611d34c27..adb25718e4 100644
--- a/activesupport/lib/active_support/core_ext/array/wrap.rb
+++ b/activesupport/lib/active_support/core_ext/array/wrap.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Array
   # Wraps its argument in an array unless it is already an array (or array-like).
   #
diff --git a/activesupport/lib/active_support/core_ext/benchmark.rb b/activesupport/lib/active_support/core_ext/benchmark.rb
index 2300953860..2db6e5f1c5 100644
--- a/activesupport/lib/active_support/core_ext/benchmark.rb
+++ b/activesupport/lib/active_support/core_ext/benchmark.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "benchmark"
 
 class << Benchmark
diff --git a/activesupport/lib/active_support/core_ext/big_decimal.rb b/activesupport/lib/active_support/core_ext/big_decimal.rb
index 7b4f87f10e..b02bae8804 100644
--- a/activesupport/lib/active_support/core_ext/big_decimal.rb
+++ b/activesupport/lib/active_support/core_ext/big_decimal.rb
@@ -1 +1,2 @@
+# frozen_string_literal: true
 require "active_support/core_ext/big_decimal/conversions"
diff --git a/activesupport/lib/active_support/core_ext/big_decimal/conversions.rb b/activesupport/lib/active_support/core_ext/big_decimal/conversions.rb
index decd4e1699..1729f00530 100644
--- a/activesupport/lib/active_support/core_ext/big_decimal/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/big_decimal/conversions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bigdecimal"
 require "bigdecimal/util"
 
diff --git a/activesupport/lib/active_support/core_ext/class.rb b/activesupport/lib/active_support/core_ext/class.rb
index 6a19e862d0..059f0a9097 100644
--- a/activesupport/lib/active_support/core_ext/class.rb
+++ b/activesupport/lib/active_support/core_ext/class.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 require "active_support/core_ext/class/attribute"
 require "active_support/core_ext/class/subclasses"
diff --git a/activesupport/lib/active_support/core_ext/class/attribute.rb b/activesupport/lib/active_support/core_ext/class/attribute.rb
index 8caddcd5c3..2fd4b18d3f 100644
--- a/activesupport/lib/active_support/core_ext/class/attribute.rb
+++ b/activesupport/lib/active_support/core_ext/class/attribute.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/kernel/singleton_class"
 require "active_support/core_ext/module/remove_method"
 require "active_support/core_ext/array/extract_options"
diff --git a/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb b/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
index 0f767925ed..fb92c5d3d1 100644
--- a/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
+++ b/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # cattr_* became mattr_* aliases in 7dfbd91b0780fbd6a1dd9bfbc176e10894871d2d,
 # but we keep this around for libraries that directly require it knowing they
 # want cattr_*. No need to deprecate.
diff --git a/activesupport/lib/active_support/core_ext/class/subclasses.rb b/activesupport/lib/active_support/core_ext/class/subclasses.rb
index 62397d9508..f92ccdbf88 100644
--- a/activesupport/lib/active_support/core_ext/class/subclasses.rb
+++ b/activesupport/lib/active_support/core_ext/class/subclasses.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/module/anonymous"
 require "active_support/core_ext/module/reachable"
 
diff --git a/activesupport/lib/active_support/core_ext/date.rb b/activesupport/lib/active_support/core_ext/date.rb
index 4f66804da2..1598be9ba6 100644
--- a/activesupport/lib/active_support/core_ext/date.rb
+++ b/activesupport/lib/active_support/core_ext/date.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/date/acts_like"
 require "active_support/core_ext/date/blank"
 require "active_support/core_ext/date/calculations"
diff --git a/activesupport/lib/active_support/core_ext/date/acts_like.rb b/activesupport/lib/active_support/core_ext/date/acts_like.rb
index 46fe99ad47..6c125d279c 100644
--- a/activesupport/lib/active_support/core_ext/date/acts_like.rb
+++ b/activesupport/lib/active_support/core_ext/date/acts_like.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/object/acts_like"
 
 class Date
diff --git a/activesupport/lib/active_support/core_ext/date/blank.rb b/activesupport/lib/active_support/core_ext/date/blank.rb
index edd2847126..a28e726902 100644
--- a/activesupport/lib/active_support/core_ext/date/blank.rb
+++ b/activesupport/lib/active_support/core_ext/date/blank.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "date"
 
 class Date #:nodoc:
diff --git a/activesupport/lib/active_support/core_ext/date/calculations.rb b/activesupport/lib/active_support/core_ext/date/calculations.rb
index d6f60cac04..c0f4fdae80 100644
--- a/activesupport/lib/active_support/core_ext/date/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date/calculations.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "date"
 require "active_support/duration"
 require "active_support/core_ext/object/acts_like"
diff --git a/activesupport/lib/active_support/core_ext/date/conversions.rb b/activesupport/lib/active_support/core_ext/date/conversions.rb
index 0f59c754fe..a36d5d844d 100644
--- a/activesupport/lib/active_support/core_ext/date/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/date/conversions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "date"
 require "active_support/inflector/methods"
 require "active_support/core_ext/date/zones"
diff --git a/activesupport/lib/active_support/core_ext/date/zones.rb b/activesupport/lib/active_support/core_ext/date/zones.rb
index da23fe4892..6aa0852e07 100644
--- a/activesupport/lib/active_support/core_ext/date/zones.rb
+++ b/activesupport/lib/active_support/core_ext/date/zones.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "date"
 require "active_support/core_ext/date_and_time/zones"
 
diff --git a/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb b/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb
index e2e1d3e359..1fa629e017 100644
--- a/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/object/try"
 
 module DateAndTime
diff --git a/activesupport/lib/active_support/core_ext/date_and_time/compatibility.rb b/activesupport/lib/active_support/core_ext/date_and_time/compatibility.rb
index 2d45e16546..078ac88229 100644
--- a/activesupport/lib/active_support/core_ext/date_and_time/compatibility.rb
+++ b/activesupport/lib/active_support/core_ext/date_and_time/compatibility.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/module/attribute_accessors"
 
 module DateAndTime
diff --git a/activesupport/lib/active_support/core_ext/date_and_time/zones.rb b/activesupport/lib/active_support/core_ext/date_and_time/zones.rb
index edd724f1d0..4cc94d4ece 100644
--- a/activesupport/lib/active_support/core_ext/date_and_time/zones.rb
+++ b/activesupport/lib/active_support/core_ext/date_and_time/zones.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module DateAndTime
   module Zones
     # Returns the simultaneous time in <tt>Time.zone</tt> if a zone is given or
diff --git a/activesupport/lib/active_support/core_ext/date_time.rb b/activesupport/lib/active_support/core_ext/date_time.rb
index 6fd498f864..5f238079c0 100644
--- a/activesupport/lib/active_support/core_ext/date_time.rb
+++ b/activesupport/lib/active_support/core_ext/date_time.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/date_time/acts_like"
 require "active_support/core_ext/date_time/blank"
 require "active_support/core_ext/date_time/calculations"
diff --git a/activesupport/lib/active_support/core_ext/date_time/acts_like.rb b/activesupport/lib/active_support/core_ext/date_time/acts_like.rb
index 6f50f55a53..774ff692c4 100644
--- a/activesupport/lib/active_support/core_ext/date_time/acts_like.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/acts_like.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "date"
 require "active_support/core_ext/object/acts_like"
 
diff --git a/activesupport/lib/active_support/core_ext/date_time/blank.rb b/activesupport/lib/active_support/core_ext/date_time/blank.rb
index b475fd926d..874c7554a3 100644
--- a/activesupport/lib/active_support/core_ext/date_time/blank.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/blank.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "date"
 
 class DateTime #:nodoc:
diff --git a/activesupport/lib/active_support/core_ext/date_time/calculations.rb b/activesupport/lib/active_support/core_ext/date_time/calculations.rb
index 7a9eb8c266..91289175ed 100644
--- a/activesupport/lib/active_support/core_ext/date_time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/calculations.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "date"
 
 class DateTime
diff --git a/activesupport/lib/active_support/core_ext/date_time/compatibility.rb b/activesupport/lib/active_support/core_ext/date_time/compatibility.rb
index 870391aeaa..fd97fbce98 100644
--- a/activesupport/lib/active_support/core_ext/date_time/compatibility.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/compatibility.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/date_and_time/compatibility"
 require "active_support/core_ext/module/remove_method"
 
diff --git a/activesupport/lib/active_support/core_ext/date_time/conversions.rb b/activesupport/lib/active_support/core_ext/date_time/conversions.rb
index d9b3743858..5c515bebbf 100644
--- a/activesupport/lib/active_support/core_ext/date_time/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/conversions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "date"
 require "active_support/inflector/methods"
 require "active_support/core_ext/time/conversions"
diff --git a/activesupport/lib/active_support/core_ext/digest/uuid.rb b/activesupport/lib/active_support/core_ext/digest/uuid.rb
index e6d60e3267..26a300feb6 100644
--- a/activesupport/lib/active_support/core_ext/digest/uuid.rb
+++ b/activesupport/lib/active_support/core_ext/digest/uuid.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "securerandom"
 
 module Digest
diff --git a/activesupport/lib/active_support/core_ext/enumerable.rb b/activesupport/lib/active_support/core_ext/enumerable.rb
index 3a4ae6cb8b..a744b78e1c 100644
--- a/activesupport/lib/active_support/core_ext/enumerable.rb
+++ b/activesupport/lib/active_support/core_ext/enumerable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Enumerable
   # Enumerable#sum was added in Ruby 2.4, but it only works with Numeric elements
   # when we omit an identity.
diff --git a/activesupport/lib/active_support/core_ext/file.rb b/activesupport/lib/active_support/core_ext/file.rb
index 6d99bad2af..a1272c02e2 100644
--- a/activesupport/lib/active_support/core_ext/file.rb
+++ b/activesupport/lib/active_support/core_ext/file.rb
@@ -1 +1,2 @@
+# frozen_string_literal: true
 require "active_support/core_ext/file/atomic"
diff --git a/activesupport/lib/active_support/core_ext/file/atomic.rb b/activesupport/lib/active_support/core_ext/file/atomic.rb
index 8d6c0d3685..5b30e93357 100644
--- a/activesupport/lib/active_support/core_ext/file/atomic.rb
+++ b/activesupport/lib/active_support/core_ext/file/atomic.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "fileutils"
 
 class File
diff --git a/activesupport/lib/active_support/core_ext/hash.rb b/activesupport/lib/active_support/core_ext/hash.rb
index c819307e8a..5d9fe68bb6 100644
--- a/activesupport/lib/active_support/core_ext/hash.rb
+++ b/activesupport/lib/active_support/core_ext/hash.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/hash/compact"
 require "active_support/core_ext/hash/conversions"
 require "active_support/core_ext/hash/deep_merge"
diff --git a/activesupport/lib/active_support/core_ext/hash/compact.rb b/activesupport/lib/active_support/core_ext/hash/compact.rb
index e357284be0..ddccbe7d16 100644
--- a/activesupport/lib/active_support/core_ext/hash/compact.rb
+++ b/activesupport/lib/active_support/core_ext/hash/compact.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Hash
   unless Hash.instance_methods(false).include?(:compact)
     # Returns a hash with non +nil+ values.
diff --git a/activesupport/lib/active_support/core_ext/hash/conversions.rb b/activesupport/lib/active_support/core_ext/hash/conversions.rb
index 2a58a7f1ca..f33a52ae2b 100644
--- a/activesupport/lib/active_support/core_ext/hash/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/hash/conversions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/xml_mini"
 require "active_support/time"
 require "active_support/core_ext/object/blank"
diff --git a/activesupport/lib/active_support/core_ext/hash/deep_merge.rb b/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
index 9c9faf67ea..1c6627a597 100644
--- a/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
+++ b/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Hash
   # Returns a new hash with +self+ and +other_hash+ merged recursively.
   #
diff --git a/activesupport/lib/active_support/core_ext/hash/except.rb b/activesupport/lib/active_support/core_ext/hash/except.rb
index 2f6d38c1f6..e31c7c61e4 100644
--- a/activesupport/lib/active_support/core_ext/hash/except.rb
+++ b/activesupport/lib/active_support/core_ext/hash/except.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Hash
   # Returns a hash that includes everything except given keys.
   #   hash = { a: true, b: false, c: nil }
diff --git a/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb b/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb
index 3e1ccecb6c..74e606dcc7 100644
--- a/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb
+++ b/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/hash_with_indifferent_access"
 
 class Hash
diff --git a/activesupport/lib/active_support/core_ext/hash/keys.rb b/activesupport/lib/active_support/core_ext/hash/keys.rb
index b7089357a8..b38ea9ba50 100644
--- a/activesupport/lib/active_support/core_ext/hash/keys.rb
+++ b/activesupport/lib/active_support/core_ext/hash/keys.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Hash
   # Returns a new hash with all keys converted using the +block+ operation.
   #
diff --git a/activesupport/lib/active_support/core_ext/hash/reverse_merge.rb b/activesupport/lib/active_support/core_ext/hash/reverse_merge.rb
index 061c959442..2055d06385 100644
--- a/activesupport/lib/active_support/core_ext/hash/reverse_merge.rb
+++ b/activesupport/lib/active_support/core_ext/hash/reverse_merge.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Hash
   # Merges the caller into +other_hash+. For example,
   #
diff --git a/activesupport/lib/active_support/core_ext/hash/slice.rb b/activesupport/lib/active_support/core_ext/hash/slice.rb
index 161b00dfb3..bd370931e4 100644
--- a/activesupport/lib/active_support/core_ext/hash/slice.rb
+++ b/activesupport/lib/active_support/core_ext/hash/slice.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Hash
   # Slices a hash to include only the given keys. Returns a hash containing
   # the given keys.
diff --git a/activesupport/lib/active_support/core_ext/hash/transform_values.rb b/activesupport/lib/active_support/core_ext/hash/transform_values.rb
index 2f693bff0c..b6e2734193 100644
--- a/activesupport/lib/active_support/core_ext/hash/transform_values.rb
+++ b/activesupport/lib/active_support/core_ext/hash/transform_values.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Hash
   # Returns a new hash with the results of running +block+ once for every value.
   # The keys are unchanged.
diff --git a/activesupport/lib/active_support/core_ext/integer.rb b/activesupport/lib/active_support/core_ext/integer.rb
index 8f0c55f9d3..21c6d9e0cc 100644
--- a/activesupport/lib/active_support/core_ext/integer.rb
+++ b/activesupport/lib/active_support/core_ext/integer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/integer/multiple"
 require "active_support/core_ext/integer/inflections"
 require "active_support/core_ext/integer/time"
diff --git a/activesupport/lib/active_support/core_ext/integer/inflections.rb b/activesupport/lib/active_support/core_ext/integer/inflections.rb
index bc21b65533..945817793d 100644
--- a/activesupport/lib/active_support/core_ext/integer/inflections.rb
+++ b/activesupport/lib/active_support/core_ext/integer/inflections.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/inflector"
 
 class Integer
diff --git a/activesupport/lib/active_support/core_ext/integer/multiple.rb b/activesupport/lib/active_support/core_ext/integer/multiple.rb
index c668c7c2eb..2e4d78e66c 100644
--- a/activesupport/lib/active_support/core_ext/integer/multiple.rb
+++ b/activesupport/lib/active_support/core_ext/integer/multiple.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Integer
   # Check whether the integer is evenly divisible by the argument.
   #
diff --git a/activesupport/lib/active_support/core_ext/integer/time.rb b/activesupport/lib/active_support/core_ext/integer/time.rb
index 74baae3639..be0958a495 100644
--- a/activesupport/lib/active_support/core_ext/integer/time.rb
+++ b/activesupport/lib/active_support/core_ext/integer/time.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/duration"
 require "active_support/core_ext/numeric/time"
 
diff --git a/activesupport/lib/active_support/core_ext/kernel.rb b/activesupport/lib/active_support/core_ext/kernel.rb
index 3d41ff7876..9e75d29cab 100644
--- a/activesupport/lib/active_support/core_ext/kernel.rb
+++ b/activesupport/lib/active_support/core_ext/kernel.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/kernel/agnostics"
 require "active_support/core_ext/kernel/concern"
 require "active_support/core_ext/kernel/reporting"
diff --git a/activesupport/lib/active_support/core_ext/kernel/agnostics.rb b/activesupport/lib/active_support/core_ext/kernel/agnostics.rb
index 64837d87aa..84a48979c4 100644
--- a/activesupport/lib/active_support/core_ext/kernel/agnostics.rb
+++ b/activesupport/lib/active_support/core_ext/kernel/agnostics.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Object
   # Makes backticks behave (somewhat more) similarly on all platforms.
   # On win32 `nonexistent_command` raises Errno::ENOENT; on Unix, the
diff --git a/activesupport/lib/active_support/core_ext/kernel/concern.rb b/activesupport/lib/active_support/core_ext/kernel/concern.rb
index 307a7f7a63..9d170e0a64 100644
--- a/activesupport/lib/active_support/core_ext/kernel/concern.rb
+++ b/activesupport/lib/active_support/core_ext/kernel/concern.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/module/concerning"
 
 module Kernel
diff --git a/activesupport/lib/active_support/core_ext/kernel/reporting.rb b/activesupport/lib/active_support/core_ext/kernel/reporting.rb
index c02618d5f3..822efb5aae 100644
--- a/activesupport/lib/active_support/core_ext/kernel/reporting.rb
+++ b/activesupport/lib/active_support/core_ext/kernel/reporting.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Kernel
   module_function
 
diff --git a/activesupport/lib/active_support/core_ext/kernel/singleton_class.rb b/activesupport/lib/active_support/core_ext/kernel/singleton_class.rb
index 9bbf1bbd73..5f9c008f6e 100644
--- a/activesupport/lib/active_support/core_ext/kernel/singleton_class.rb
+++ b/activesupport/lib/active_support/core_ext/kernel/singleton_class.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Kernel
   # class_eval on an object acts like singleton_class.class_eval.
   def class_eval(*args, &block)
diff --git a/activesupport/lib/active_support/core_ext/load_error.rb b/activesupport/lib/active_support/core_ext/load_error.rb
index d273487010..55177efdaf 100644
--- a/activesupport/lib/active_support/core_ext/load_error.rb
+++ b/activesupport/lib/active_support/core_ext/load_error.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class LoadError
   REGEXPS = [
     /^no such file to load -- (.+)$/i,
diff --git a/activesupport/lib/active_support/core_ext/marshal.rb b/activesupport/lib/active_support/core_ext/marshal.rb
index bba2b3be2e..13b1d0cf95 100644
--- a/activesupport/lib/active_support/core_ext/marshal.rb
+++ b/activesupport/lib/active_support/core_ext/marshal.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module ActiveSupport
   module MarshalWithAutoloading # :nodoc:
     def load(source, proc = nil)
diff --git a/activesupport/lib/active_support/core_ext/module.rb b/activesupport/lib/active_support/core_ext/module.rb
index 2930255557..6fe85c30a6 100644
--- a/activesupport/lib/active_support/core_ext/module.rb
+++ b/activesupport/lib/active_support/core_ext/module.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/module/aliasing"
 require "active_support/core_ext/module/introspection"
 require "active_support/core_ext/module/anonymous"
diff --git a/activesupport/lib/active_support/core_ext/module/aliasing.rb b/activesupport/lib/active_support/core_ext/module/aliasing.rb
index c48bd3354a..62eb9e4c76 100644
--- a/activesupport/lib/active_support/core_ext/module/aliasing.rb
+++ b/activesupport/lib/active_support/core_ext/module/aliasing.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Module
   # Allows you to make aliases for attributes, which includes
   # getter, setter, and a predicate.
diff --git a/activesupport/lib/active_support/core_ext/module/anonymous.rb b/activesupport/lib/active_support/core_ext/module/anonymous.rb
index 510c9a5430..7d10240199 100644
--- a/activesupport/lib/active_support/core_ext/module/anonymous.rb
+++ b/activesupport/lib/active_support/core_ext/module/anonymous.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Module
   # A module may or may not have a name.
   #
diff --git a/activesupport/lib/active_support/core_ext/module/attr_internal.rb b/activesupport/lib/active_support/core_ext/module/attr_internal.rb
index 5081d5f7a3..8d37460dbc 100644
--- a/activesupport/lib/active_support/core_ext/module/attr_internal.rb
+++ b/activesupport/lib/active_support/core_ext/module/attr_internal.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Module
   # Declares an attribute reader backed by an internally-named instance variable.
   def attr_internal_reader(*attrs)
diff --git a/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb b/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
index 9244cfa157..9276755374 100644
--- a/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
+++ b/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/array/extract_options"
 require "active_support/core_ext/regexp"
 
diff --git a/activesupport/lib/active_support/core_ext/module/attribute_accessors_per_thread.rb b/activesupport/lib/active_support/core_ext/module/attribute_accessors_per_thread.rb
index 1e82b4acc2..348563b1f7 100644
--- a/activesupport/lib/active_support/core_ext/module/attribute_accessors_per_thread.rb
+++ b/activesupport/lib/active_support/core_ext/module/attribute_accessors_per_thread.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/array/extract_options"
 require "active_support/core_ext/regexp"
 
diff --git a/activesupport/lib/active_support/core_ext/module/concerning.rb b/activesupport/lib/active_support/core_ext/module/concerning.rb
index 97b0a382ce..bc22e3169b 100644
--- a/activesupport/lib/active_support/core_ext/module/concerning.rb
+++ b/activesupport/lib/active_support/core_ext/module/concerning.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/concern"
 
 class Module
diff --git a/activesupport/lib/active_support/core_ext/module/delegation.rb b/activesupport/lib/active_support/core_ext/module/delegation.rb
index 13f3894e6c..ccc33609b7 100644
--- a/activesupport/lib/active_support/core_ext/module/delegation.rb
+++ b/activesupport/lib/active_support/core_ext/module/delegation.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "set"
 require "active_support/core_ext/regexp"
 
diff --git a/activesupport/lib/active_support/core_ext/module/deprecation.rb b/activesupport/lib/active_support/core_ext/module/deprecation.rb
index f3f2e7f5fc..98dfaad760 100644
--- a/activesupport/lib/active_support/core_ext/module/deprecation.rb
+++ b/activesupport/lib/active_support/core_ext/module/deprecation.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Module
   #   deprecate :foo
   #   deprecate bar: 'message'
diff --git a/activesupport/lib/active_support/core_ext/module/introspection.rb b/activesupport/lib/active_support/core_ext/module/introspection.rb
index ca20a6d4c5..1e1c3870f5 100644
--- a/activesupport/lib/active_support/core_ext/module/introspection.rb
+++ b/activesupport/lib/active_support/core_ext/module/introspection.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/inflector"
 
 class Module
diff --git a/activesupport/lib/active_support/core_ext/module/reachable.rb b/activesupport/lib/active_support/core_ext/module/reachable.rb
index b89a38f26c..8cb09dd259 100644
--- a/activesupport/lib/active_support/core_ext/module/reachable.rb
+++ b/activesupport/lib/active_support/core_ext/module/reachable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/module/anonymous"
 require "active_support/core_ext/string/inflections"
 
diff --git a/activesupport/lib/active_support/core_ext/module/remove_method.rb b/activesupport/lib/active_support/core_ext/module/remove_method.rb
index d5ec16d68a..c17808b244 100644
--- a/activesupport/lib/active_support/core_ext/module/remove_method.rb
+++ b/activesupport/lib/active_support/core_ext/module/remove_method.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Module
   # Removes the named method, if it exists.
   def remove_possible_method(method)
diff --git a/activesupport/lib/active_support/core_ext/name_error.rb b/activesupport/lib/active_support/core_ext/name_error.rb
index 6b447d772b..1bcb6ded3c 100644
--- a/activesupport/lib/active_support/core_ext/name_error.rb
+++ b/activesupport/lib/active_support/core_ext/name_error.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class NameError
   # Extract the name of the missing constant from the exception message.
   #
diff --git a/activesupport/lib/active_support/core_ext/numeric.rb b/activesupport/lib/active_support/core_ext/numeric.rb
index 6062f9e3a8..402e9d4323 100644
--- a/activesupport/lib/active_support/core_ext/numeric.rb
+++ b/activesupport/lib/active_support/core_ext/numeric.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/numeric/bytes"
 require "active_support/core_ext/numeric/time"
 require "active_support/core_ext/numeric/inquiry"
diff --git a/activesupport/lib/active_support/core_ext/numeric/bytes.rb b/activesupport/lib/active_support/core_ext/numeric/bytes.rb
index dfbca32474..23e1e39dd8 100644
--- a/activesupport/lib/active_support/core_ext/numeric/bytes.rb
+++ b/activesupport/lib/active_support/core_ext/numeric/bytes.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Numeric
   KILOBYTE = 1024
   MEGABYTE = KILOBYTE * 1024
diff --git a/activesupport/lib/active_support/core_ext/numeric/conversions.rb b/activesupport/lib/active_support/core_ext/numeric/conversions.rb
index 4f6621693e..bedfe5ce32 100644
--- a/activesupport/lib/active_support/core_ext/numeric/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/numeric/conversions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/big_decimal/conversions"
 require "active_support/number_helper"
 require "active_support/core_ext/module/deprecation"
diff --git a/activesupport/lib/active_support/core_ext/numeric/inquiry.rb b/activesupport/lib/active_support/core_ext/numeric/inquiry.rb
index ec79701189..baccf87848 100644
--- a/activesupport/lib/active_support/core_ext/numeric/inquiry.rb
+++ b/activesupport/lib/active_support/core_ext/numeric/inquiry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 unless 1.respond_to?(:positive?) # TODO: Remove this file when we drop support to ruby < 2.3
   class Numeric
     # Returns true if the number is positive.
diff --git a/activesupport/lib/active_support/core_ext/numeric/time.rb b/activesupport/lib/active_support/core_ext/numeric/time.rb
index 2e6c70d418..95f73fb336 100644
--- a/activesupport/lib/active_support/core_ext/numeric/time.rb
+++ b/activesupport/lib/active_support/core_ext/numeric/time.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/duration"
 require "active_support/core_ext/time/calculations"
 require "active_support/core_ext/time/acts_like"
diff --git a/activesupport/lib/active_support/core_ext/object.rb b/activesupport/lib/active_support/core_ext/object.rb
index 58bbf78601..f3cd8b0898 100644
--- a/activesupport/lib/active_support/core_ext/object.rb
+++ b/activesupport/lib/active_support/core_ext/object.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/object/acts_like"
 require "active_support/core_ext/object/blank"
 require "active_support/core_ext/object/duplicable"
diff --git a/activesupport/lib/active_support/core_ext/object/acts_like.rb b/activesupport/lib/active_support/core_ext/object/acts_like.rb
index 3912cc5ace..b856e1ba16 100644
--- a/activesupport/lib/active_support/core_ext/object/acts_like.rb
+++ b/activesupport/lib/active_support/core_ext/object/acts_like.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Object
   # A duck-type assistant method. For example, Active Support extends Date
   # to define an <tt>acts_like_date?</tt> method, and extends Time to define
diff --git a/activesupport/lib/active_support/core_ext/object/blank.rb b/activesupport/lib/active_support/core_ext/object/blank.rb
index bdb50ee291..3ad4605235 100644
--- a/activesupport/lib/active_support/core_ext/object/blank.rb
+++ b/activesupport/lib/active_support/core_ext/object/blank.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/regexp"
 
 class Object
diff --git a/activesupport/lib/active_support/core_ext/object/conversions.rb b/activesupport/lib/active_support/core_ext/object/conversions.rb
index 918ebcdc9f..2626d9ed29 100644
--- a/activesupport/lib/active_support/core_ext/object/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/object/conversions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/object/to_param"
 require "active_support/core_ext/object/to_query"
 require "active_support/core_ext/array/conversions"
diff --git a/activesupport/lib/active_support/core_ext/object/deep_dup.rb b/activesupport/lib/active_support/core_ext/object/deep_dup.rb
index 5ac649e552..ce1f765448 100644
--- a/activesupport/lib/active_support/core_ext/object/deep_dup.rb
+++ b/activesupport/lib/active_support/core_ext/object/deep_dup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/object/duplicable"
 
 class Object
diff --git a/activesupport/lib/active_support/core_ext/object/duplicable.rb b/activesupport/lib/active_support/core_ext/object/duplicable.rb
index b028df97ee..0838b1fb70 100644
--- a/activesupport/lib/active_support/core_ext/object/duplicable.rb
+++ b/activesupport/lib/active_support/core_ext/object/duplicable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 #--
 # Most objects are cloneable, but not all. For example you can't dup methods:
 #
diff --git a/activesupport/lib/active_support/core_ext/object/inclusion.rb b/activesupport/lib/active_support/core_ext/object/inclusion.rb
index 98bf820d36..525ddcb575 100644
--- a/activesupport/lib/active_support/core_ext/object/inclusion.rb
+++ b/activesupport/lib/active_support/core_ext/object/inclusion.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Object
   # Returns true if this object is included in the argument. Argument must be
   # any object which responds to +#include?+. Usage:
diff --git a/activesupport/lib/active_support/core_ext/object/instance_variables.rb b/activesupport/lib/active_support/core_ext/object/instance_variables.rb
index 593a7a4940..0a06125210 100644
--- a/activesupport/lib/active_support/core_ext/object/instance_variables.rb
+++ b/activesupport/lib/active_support/core_ext/object/instance_variables.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Object
   # Returns a hash with string keys that maps instance variable names without "@" to their
   # corresponding values.
diff --git a/activesupport/lib/active_support/core_ext/object/json.rb b/activesupport/lib/active_support/core_ext/object/json.rb
index 1c4d181443..87e5cdce0d 100644
--- a/activesupport/lib/active_support/core_ext/object/json.rb
+++ b/activesupport/lib/active_support/core_ext/object/json.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # Hack to load json gem first so we can overwrite its to_json.
 require "json"
 require "bigdecimal"
diff --git a/activesupport/lib/active_support/core_ext/object/to_param.rb b/activesupport/lib/active_support/core_ext/object/to_param.rb
index 5eeaf03163..58e60b5d4e 100644
--- a/activesupport/lib/active_support/core_ext/object/to_param.rb
+++ b/activesupport/lib/active_support/core_ext/object/to_param.rb
@@ -1 +1,2 @@
+# frozen_string_literal: true
 require "active_support/core_ext/object/to_query"
diff --git a/activesupport/lib/active_support/core_ext/object/to_query.rb b/activesupport/lib/active_support/core_ext/object/to_query.rb
index a3a3abacbb..f85e0eaa6f 100644
--- a/activesupport/lib/active_support/core_ext/object/to_query.rb
+++ b/activesupport/lib/active_support/core_ext/object/to_query.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cgi"
 
 class Object
diff --git a/activesupport/lib/active_support/core_ext/object/try.rb b/activesupport/lib/active_support/core_ext/object/try.rb
index b2be619b2d..952fba4541 100644
--- a/activesupport/lib/active_support/core_ext/object/try.rb
+++ b/activesupport/lib/active_support/core_ext/object/try.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "delegate"
 
 module ActiveSupport
diff --git a/activesupport/lib/active_support/core_ext/object/with_options.rb b/activesupport/lib/active_support/core_ext/object/with_options.rb
index 3a44e08630..bc3075b5f1 100644
--- a/activesupport/lib/active_support/core_ext/object/with_options.rb
+++ b/activesupport/lib/active_support/core_ext/object/with_options.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/option_merger"
 
 class Object
diff --git a/activesupport/lib/active_support/core_ext/range.rb b/activesupport/lib/active_support/core_ext/range.rb
index 3190e3ff76..9d84cbcec2 100644
--- a/activesupport/lib/active_support/core_ext/range.rb
+++ b/activesupport/lib/active_support/core_ext/range.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/range/conversions"
 require "active_support/core_ext/range/include_range"
 require "active_support/core_ext/range/overlaps"
diff --git a/activesupport/lib/active_support/core_ext/range/conversions.rb b/activesupport/lib/active_support/core_ext/range/conversions.rb
index 69ea046cb6..5038a15cdf 100644
--- a/activesupport/lib/active_support/core_ext/range/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/range/conversions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module ActiveSupport::RangeWithFormat
   RANGE_FORMATS = {
     db: Proc.new { |start, stop| "BETWEEN '#{start.to_s(:db)}' AND '#{stop.to_s(:db)}'" }
diff --git a/activesupport/lib/active_support/core_ext/range/each.rb b/activesupport/lib/active_support/core_ext/range/each.rb
index dc6dad5ced..aeea8c867b 100644
--- a/activesupport/lib/active_support/core_ext/range/each.rb
+++ b/activesupport/lib/active_support/core_ext/range/each.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module ActiveSupport
   module EachTimeWithZone #:nodoc:
     def each(&block)
diff --git a/activesupport/lib/active_support/core_ext/range/include_range.rb b/activesupport/lib/active_support/core_ext/range/include_range.rb
index c69e1e3fb9..d307750a23 100644
--- a/activesupport/lib/active_support/core_ext/range/include_range.rb
+++ b/activesupport/lib/active_support/core_ext/range/include_range.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module ActiveSupport
   module IncludeWithRange #:nodoc:
     # Extends the default Range#include? to support range comparisons.
diff --git a/activesupport/lib/active_support/core_ext/range/overlaps.rb b/activesupport/lib/active_support/core_ext/range/overlaps.rb
index 603657c180..ecdfbd803b 100644
--- a/activesupport/lib/active_support/core_ext/range/overlaps.rb
+++ b/activesupport/lib/active_support/core_ext/range/overlaps.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Range
   # Compare two ranges and see if they overlap each other
   #  (1..5).overlaps?(4..6) # => true
diff --git a/activesupport/lib/active_support/core_ext/regexp.rb b/activesupport/lib/active_support/core_ext/regexp.rb
index d77d01bf42..23b337ba67 100644
--- a/activesupport/lib/active_support/core_ext/regexp.rb
+++ b/activesupport/lib/active_support/core_ext/regexp.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Regexp #:nodoc:
   def multiline?
     options & MULTILINE == MULTILINE
diff --git a/activesupport/lib/active_support/core_ext/securerandom.rb b/activesupport/lib/active_support/core_ext/securerandom.rb
index a57685bea1..033ac356bd 100644
--- a/activesupport/lib/active_support/core_ext/securerandom.rb
+++ b/activesupport/lib/active_support/core_ext/securerandom.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "securerandom"
 
 module SecureRandom
diff --git a/activesupport/lib/active_support/core_ext/string.rb b/activesupport/lib/active_support/core_ext/string.rb
index 4cb3200875..cfac17f810 100644
--- a/activesupport/lib/active_support/core_ext/string.rb
+++ b/activesupport/lib/active_support/core_ext/string.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/string/conversions"
 require "active_support/core_ext/string/filters"
 require "active_support/core_ext/string/multibyte"
diff --git a/activesupport/lib/active_support/core_ext/string/access.rb b/activesupport/lib/active_support/core_ext/string/access.rb
index 6133826f37..11f4bf8052 100644
--- a/activesupport/lib/active_support/core_ext/string/access.rb
+++ b/activesupport/lib/active_support/core_ext/string/access.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class String
   # If you pass a single integer, returns a substring of one character at that
   # position. The first character of the string is at position 0, the next at
diff --git a/activesupport/lib/active_support/core_ext/string/behavior.rb b/activesupport/lib/active_support/core_ext/string/behavior.rb
index 710f1f4670..e63888991d 100644
--- a/activesupport/lib/active_support/core_ext/string/behavior.rb
+++ b/activesupport/lib/active_support/core_ext/string/behavior.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class String
   # Enables more predictable duck-typing on String-like classes. See <tt>Object#acts_like?</tt>.
   def acts_like_string?
diff --git a/activesupport/lib/active_support/core_ext/string/conversions.rb b/activesupport/lib/active_support/core_ext/string/conversions.rb
index 221b4969cc..79668312c5 100644
--- a/activesupport/lib/active_support/core_ext/string/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/string/conversions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "date"
 require "active_support/core_ext/time/calculations"
 
diff --git a/activesupport/lib/active_support/core_ext/string/exclude.rb b/activesupport/lib/active_support/core_ext/string/exclude.rb
index 0ac684f6ee..2893a6eeed 100644
--- a/activesupport/lib/active_support/core_ext/string/exclude.rb
+++ b/activesupport/lib/active_support/core_ext/string/exclude.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class String
   # The inverse of <tt>String#include?</tt>. Returns true if the string
   # does not include the other string.
diff --git a/activesupport/lib/active_support/core_ext/string/filters.rb b/activesupport/lib/active_support/core_ext/string/filters.rb
index a9ec2eb842..e05cf024f6 100644
--- a/activesupport/lib/active_support/core_ext/string/filters.rb
+++ b/activesupport/lib/active_support/core_ext/string/filters.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class String
   # Returns the string, first removing all whitespace on both ends of
   # the string, and then changing remaining consecutive whitespace
diff --git a/activesupport/lib/active_support/core_ext/string/indent.rb b/activesupport/lib/active_support/core_ext/string/indent.rb
index d7b58301d3..a38198a8e6 100644
--- a/activesupport/lib/active_support/core_ext/string/indent.rb
+++ b/activesupport/lib/active_support/core_ext/string/indent.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class String
   # Same as +indent+, except it indents the receiver in-place.
   #
diff --git a/activesupport/lib/active_support/core_ext/string/inflections.rb b/activesupport/lib/active_support/core_ext/string/inflections.rb
index b27cfe53f4..63bb52b2da 100644
--- a/activesupport/lib/active_support/core_ext/string/inflections.rb
+++ b/activesupport/lib/active_support/core_ext/string/inflections.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/inflector/methods"
 require "active_support/inflector/transliterate"
 
diff --git a/activesupport/lib/active_support/core_ext/string/inquiry.rb b/activesupport/lib/active_support/core_ext/string/inquiry.rb
index c95d83beae..874efc6ae3 100644
--- a/activesupport/lib/active_support/core_ext/string/inquiry.rb
+++ b/activesupport/lib/active_support/core_ext/string/inquiry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/string_inquirer"
 
 class String
diff --git a/activesupport/lib/active_support/core_ext/string/multibyte.rb b/activesupport/lib/active_support/core_ext/string/multibyte.rb
index 1c73182259..aee0bb4bf3 100644
--- a/activesupport/lib/active_support/core_ext/string/multibyte.rb
+++ b/activesupport/lib/active_support/core_ext/string/multibyte.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/multibyte"
 
 class String
diff --git a/activesupport/lib/active_support/core_ext/string/output_safety.rb b/activesupport/lib/active_support/core_ext/string/output_safety.rb
index 94ce3f6a61..c26f1edc88 100644
--- a/activesupport/lib/active_support/core_ext/string/output_safety.rb
+++ b/activesupport/lib/active_support/core_ext/string/output_safety.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "erb"
 require "active_support/core_ext/kernel/singleton_class"
 require "active_support/multibyte/unicode"
diff --git a/activesupport/lib/active_support/core_ext/string/starts_ends_with.rb b/activesupport/lib/active_support/core_ext/string/starts_ends_with.rb
index 641acf62d0..f072fbf7d7 100644
--- a/activesupport/lib/active_support/core_ext/string/starts_ends_with.rb
+++ b/activesupport/lib/active_support/core_ext/string/starts_ends_with.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class String
   alias_method :starts_with?, :start_with?
   alias_method :ends_with?, :end_with?
diff --git a/activesupport/lib/active_support/core_ext/string/strip.rb b/activesupport/lib/active_support/core_ext/string/strip.rb
index bb62e6c0ba..979b6bd767 100644
--- a/activesupport/lib/active_support/core_ext/string/strip.rb
+++ b/activesupport/lib/active_support/core_ext/string/strip.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class String
   # Strips indentation in heredocs.
   #
diff --git a/activesupport/lib/active_support/core_ext/string/zones.rb b/activesupport/lib/active_support/core_ext/string/zones.rb
index de5a28e4f7..a327bdc782 100644
--- a/activesupport/lib/active_support/core_ext/string/zones.rb
+++ b/activesupport/lib/active_support/core_ext/string/zones.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/string/conversions"
 require "active_support/core_ext/time/zones"
 
diff --git a/activesupport/lib/active_support/core_ext/time.rb b/activesupport/lib/active_support/core_ext/time.rb
index b1ae4a45d9..92f5cdde9f 100644
--- a/activesupport/lib/active_support/core_ext/time.rb
+++ b/activesupport/lib/active_support/core_ext/time.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/time/acts_like"
 require "active_support/core_ext/time/calculations"
 require "active_support/core_ext/time/compatibility"
diff --git a/activesupport/lib/active_support/core_ext/time/acts_like.rb b/activesupport/lib/active_support/core_ext/time/acts_like.rb
index cf4b2539c5..fb81cd41af 100644
--- a/activesupport/lib/active_support/core_ext/time/acts_like.rb
+++ b/activesupport/lib/active_support/core_ext/time/acts_like.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/object/acts_like"
 
 class Time
diff --git a/activesupport/lib/active_support/core_ext/time/calculations.rb b/activesupport/lib/active_support/core_ext/time/calculations.rb
index d3f23f4663..011291f693 100644
--- a/activesupport/lib/active_support/core_ext/time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/time/calculations.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/duration"
 require "active_support/core_ext/time/conversions"
 require "active_support/time_with_zone"
diff --git a/activesupport/lib/active_support/core_ext/time/compatibility.rb b/activesupport/lib/active_support/core_ext/time/compatibility.rb
index 45e86b77ce..9acd18d012 100644
--- a/activesupport/lib/active_support/core_ext/time/compatibility.rb
+++ b/activesupport/lib/active_support/core_ext/time/compatibility.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/date_and_time/compatibility"
 require "active_support/core_ext/module/remove_method"
 
diff --git a/activesupport/lib/active_support/core_ext/time/conversions.rb b/activesupport/lib/active_support/core_ext/time/conversions.rb
index 595bda6b4f..e07bc5a93a 100644
--- a/activesupport/lib/active_support/core_ext/time/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/time/conversions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/inflector/methods"
 require "active_support/values/time_zone"
 
diff --git a/activesupport/lib/active_support/core_ext/time/zones.rb b/activesupport/lib/active_support/core_ext/time/zones.rb
index 87b5ad903a..93e57ae4f2 100644
--- a/activesupport/lib/active_support/core_ext/time/zones.rb
+++ b/activesupport/lib/active_support/core_ext/time/zones.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/time_with_zone"
 require "active_support/core_ext/time/acts_like"
 require "active_support/core_ext/date_and_time/zones"
diff --git a/activesupport/lib/active_support/core_ext/uri.rb b/activesupport/lib/active_support/core_ext/uri.rb
index 342a5fcd52..f93dbdf2cd 100644
--- a/activesupport/lib/active_support/core_ext/uri.rb
+++ b/activesupport/lib/active_support/core_ext/uri.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "uri"
 str = "\xE6\x97\xA5\xE6\x9C\xAC\xE8\xAA\x9E" # Ni-ho-nn-go in UTF-8, means Japanese.
 parser = URI::Parser.new