diff --git a/.rubocop.yml b/.rubocop.yml
index 8c2d4e5b..7e302463 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -71,3 +71,9 @@ Gemspec/RequiredRubyVersion:
 
 Style/ModuleFunction:
   Enabled: false
+
+Style/FrozenStringLiteralComment:
+  Enabled: true
+  EnforcedStyle: always
+  Exclude:
+    - 'spec/fixtures/example_nesting.rb'
diff --git a/Gemfile b/Gemfile
index 63493654..a6981aa5 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 source 'https://rubygems.org'
 gemspec
 
diff --git a/Rakefile b/Rakefile
index 81d3b01f..3a36ec20 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'rake/clean'
 require 'rubygems/package_task'
 
diff --git a/bin/pry b/bin/pry
index e6914ce4..59b1edbc 100755
--- a/bin/pry
+++ b/bin/pry
@@ -1,4 +1,6 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: true
+
 $0 = 'pry'
 
 require 'pry'
diff --git a/lib/pry.rb b/lib/pry.rb
index 276a41e9..c33bc0cb 100644
--- a/lib/pry.rb
+++ b/lib/pry.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'pry/version'
 require 'pry/last_exception'
 require 'pry/forwardable'
diff --git a/lib/pry/basic_object.rb b/lib/pry/basic_object.rb
index 72e6d99e..73e58eba 100644
--- a/lib/pry/basic_object.rb
+++ b/lib/pry/basic_object.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class BasicObject < BasicObject
     [:Kernel, :File, :Dir, :LoadError, :ENV, :Pry].each do |constant|
diff --git a/lib/pry/block_command.rb b/lib/pry/block_command.rb
index 947f8e7d..bf74955f 100644
--- a/lib/pry/block_command.rb
+++ b/lib/pry/block_command.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # A super-class for Commands that are created with a single block.
   #
diff --git a/lib/pry/class_command.rb b/lib/pry/class_command.rb
index dde4781a..d8a4c6fc 100644
--- a/lib/pry/class_command.rb
+++ b/lib/pry/class_command.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # A super-class of Commands with structure.
   #
diff --git a/lib/pry/cli.rb b/lib/pry/cli.rb
index 1d7d7672..504cc6c4 100644
--- a/lib/pry/cli.rb
+++ b/lib/pry/cli.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'stringio'
 
 class Pry
diff --git a/lib/pry/code.rb b/lib/pry/code.rb
index dd3858d7..dcd33d4a 100644
--- a/lib/pry/code.rb
+++ b/lib/pry/code.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'method_source'
 
 class Pry
diff --git a/lib/pry/code/code_file.rb b/lib/pry/code/code_file.rb
index d120af84..c079ce7d 100644
--- a/lib/pry/code/code_file.rb
+++ b/lib/pry/code/code_file.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'method_source'
 
 class Pry
diff --git a/lib/pry/code/code_range.rb b/lib/pry/code/code_range.rb
index a28bdedb..83f7b777 100644
--- a/lib/pry/code/code_range.rb
+++ b/lib/pry/code/code_range.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Code
     # Represents a range of lines in a code listing.
diff --git a/lib/pry/code/loc.rb b/lib/pry/code/loc.rb
index 06721967..8cb3d8fe 100644
--- a/lib/pry/code/loc.rb
+++ b/lib/pry/code/loc.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Code
     # Represents a line of code (which may, in fact, contain multiple lines if
diff --git a/lib/pry/code_object.rb b/lib/pry/code_object.rb
index c9eee2a4..931e28d6 100644
--- a/lib/pry/code_object.rb
+++ b/lib/pry/code_object.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # This class is responsible for taking a string (identifying a
   # command/class/method/etc) and returning the relevant type of object.
diff --git a/lib/pry/color_printer.rb b/lib/pry/color_printer.rb
index 0487c956..0a289014 100644
--- a/lib/pry/color_printer.rb
+++ b/lib/pry/color_printer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'pp'
 require 'English'
 
diff --git a/lib/pry/command.rb b/lib/pry/command.rb
index 4e1674c7..6b274133 100644
--- a/lib/pry/command.rb
+++ b/lib/pry/command.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'delegate'
 require 'shellwords'
 
diff --git a/lib/pry/command_set.rb b/lib/pry/command_set.rb
index 57d7884e..70ec2e53 100644
--- a/lib/pry/command_set.rb
+++ b/lib/pry/command_set.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class NoCommandError < StandardError
     def initialize(match, owner)
diff --git a/lib/pry/command_state.rb b/lib/pry/command_state.rb
index 263d14d8..82c9ab95 100644
--- a/lib/pry/command_state.rb
+++ b/lib/pry/command_state.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'ostruct'
 
 class Pry
diff --git a/lib/pry/commands/amend_line.rb b/lib/pry/commands/amend_line.rb
index 31791c61..002d4713 100644
--- a/lib/pry/commands/amend_line.rb
+++ b/lib/pry/commands/amend_line.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class AmendLine < Pry::ClassCommand
diff --git a/lib/pry/commands/bang.rb b/lib/pry/commands/bang.rb
index 58bea56d..ca42834e 100644
--- a/lib/pry/commands/bang.rb
+++ b/lib/pry/commands/bang.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Bang < Pry::ClassCommand
diff --git a/lib/pry/commands/bang_pry.rb b/lib/pry/commands/bang_pry.rb
index 728fe92a..39c148ea 100644
--- a/lib/pry/commands/bang_pry.rb
+++ b/lib/pry/commands/bang_pry.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class BangPry < Pry::ClassCommand
diff --git a/lib/pry/commands/cat.rb b/lib/pry/commands/cat.rb
index f994e8cd..49dca46a 100644
--- a/lib/pry/commands/cat.rb
+++ b/lib/pry/commands/cat.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Cat < Pry::ClassCommand
diff --git a/lib/pry/commands/cat/abstract_formatter.rb b/lib/pry/commands/cat/abstract_formatter.rb
index 8e39bd4b..013869e1 100644
--- a/lib/pry/commands/cat/abstract_formatter.rb
+++ b/lib/pry/commands/cat/abstract_formatter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Cat
diff --git a/lib/pry/commands/cat/exception_formatter.rb b/lib/pry/commands/cat/exception_formatter.rb
index a4e70efd..c6d3b68a 100644
--- a/lib/pry/commands/cat/exception_formatter.rb
+++ b/lib/pry/commands/cat/exception_formatter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Cat
diff --git a/lib/pry/commands/cat/file_formatter.rb b/lib/pry/commands/cat/file_formatter.rb
index 5b6c58c9..e8f1927b 100644
--- a/lib/pry/commands/cat/file_formatter.rb
+++ b/lib/pry/commands/cat/file_formatter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Cat
diff --git a/lib/pry/commands/cat/input_expression_formatter.rb b/lib/pry/commands/cat/input_expression_formatter.rb
index 5c8102b8..4d8468fe 100644
--- a/lib/pry/commands/cat/input_expression_formatter.rb
+++ b/lib/pry/commands/cat/input_expression_formatter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Cat
diff --git a/lib/pry/commands/cd.rb b/lib/pry/commands/cd.rb
index ec7defd6..d698e0a0 100644
--- a/lib/pry/commands/cd.rb
+++ b/lib/pry/commands/cd.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Cd < Pry::ClassCommand
diff --git a/lib/pry/commands/change_inspector.rb b/lib/pry/commands/change_inspector.rb
index c4ec4fba..ea221f9f 100644
--- a/lib/pry/commands/change_inspector.rb
+++ b/lib/pry/commands/change_inspector.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ChangeInspector < Pry::ClassCommand
diff --git a/lib/pry/commands/change_prompt.rb b/lib/pry/commands/change_prompt.rb
index e3e59d14..89e85196 100644
--- a/lib/pry/commands/change_prompt.rb
+++ b/lib/pry/commands/change_prompt.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ChangePrompt < Pry::ClassCommand
diff --git a/lib/pry/commands/clear_screen.rb b/lib/pry/commands/clear_screen.rb
index 04ee762b..c0b78127 100644
--- a/lib/pry/commands/clear_screen.rb
+++ b/lib/pry/commands/clear_screen.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ClearScreen < Pry::ClassCommand
diff --git a/lib/pry/commands/code_collector.rb b/lib/pry/commands/code_collector.rb
index be0564a5..a827abf6 100644
--- a/lib/pry/commands/code_collector.rb
+++ b/lib/pry/commands/code_collector.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class CodeCollector
diff --git a/lib/pry/commands/disable_pry.rb b/lib/pry/commands/disable_pry.rb
index 9dc970f4..0c597242 100644
--- a/lib/pry/commands/disable_pry.rb
+++ b/lib/pry/commands/disable_pry.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class DisablePry < Pry::ClassCommand
diff --git a/lib/pry/commands/easter_eggs.rb b/lib/pry/commands/easter_eggs.rb
index b5883246..fba09743 100644
--- a/lib/pry/commands/easter_eggs.rb
+++ b/lib/pry/commands/easter_eggs.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   Pry::Commands.instance_eval do
     command(%r{!s/(.*?)/(.*?)}, "") do |source, dest|
diff --git a/lib/pry/commands/edit.rb b/lib/pry/commands/edit.rb
index b2ecbf55..1819f8a4 100644
--- a/lib/pry/commands/edit.rb
+++ b/lib/pry/commands/edit.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Edit < Pry::ClassCommand
diff --git a/lib/pry/commands/edit/exception_patcher.rb b/lib/pry/commands/edit/exception_patcher.rb
index 370a831d..6465d597 100644
--- a/lib/pry/commands/edit/exception_patcher.rb
+++ b/lib/pry/commands/edit/exception_patcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Edit
diff --git a/lib/pry/commands/edit/file_and_line_locator.rb b/lib/pry/commands/edit/file_and_line_locator.rb
index c6724e4a..e3b8a616 100644
--- a/lib/pry/commands/edit/file_and_line_locator.rb
+++ b/lib/pry/commands/edit/file_and_line_locator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Edit
diff --git a/lib/pry/commands/exit.rb b/lib/pry/commands/exit.rb
index 63922e2f..bbd67dd7 100644
--- a/lib/pry/commands/exit.rb
+++ b/lib/pry/commands/exit.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Exit < Pry::ClassCommand
diff --git a/lib/pry/commands/exit_all.rb b/lib/pry/commands/exit_all.rb
index 0d834bd6..e30373b4 100644
--- a/lib/pry/commands/exit_all.rb
+++ b/lib/pry/commands/exit_all.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ExitAll < Pry::ClassCommand
diff --git a/lib/pry/commands/exit_program.rb b/lib/pry/commands/exit_program.rb
index 67291549..3b52438a 100644
--- a/lib/pry/commands/exit_program.rb
+++ b/lib/pry/commands/exit_program.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ExitProgram < Pry::ClassCommand
diff --git a/lib/pry/commands/find_method.rb b/lib/pry/commands/find_method.rb
index db5e6418..31a6a319 100644
--- a/lib/pry/commands/find_method.rb
+++ b/lib/pry/commands/find_method.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class FindMethod < Pry::ClassCommand
diff --git a/lib/pry/commands/fix_indent.rb b/lib/pry/commands/fix_indent.rb
index 0a62fbe1..6c338691 100644
--- a/lib/pry/commands/fix_indent.rb
+++ b/lib/pry/commands/fix_indent.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class FixIndent < Pry::ClassCommand
diff --git a/lib/pry/commands/help.rb b/lib/pry/commands/help.rb
index 778e6e6e..03f82895 100644
--- a/lib/pry/commands/help.rb
+++ b/lib/pry/commands/help.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Help < Pry::ClassCommand
diff --git a/lib/pry/commands/hist.rb b/lib/pry/commands/hist.rb
index 69a2331b..390e992d 100644
--- a/lib/pry/commands/hist.rb
+++ b/lib/pry/commands/hist.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Hist < Pry::ClassCommand
diff --git a/lib/pry/commands/import_set.rb b/lib/pry/commands/import_set.rb
index e4ff04d8..6d09fd8f 100644
--- a/lib/pry/commands/import_set.rb
+++ b/lib/pry/commands/import_set.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ImportSet < Pry::ClassCommand
diff --git a/lib/pry/commands/jump_to.rb b/lib/pry/commands/jump_to.rb
index b48fb5e6..eca7a988 100644
--- a/lib/pry/commands/jump_to.rb
+++ b/lib/pry/commands/jump_to.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class JumpTo < Pry::ClassCommand
diff --git a/lib/pry/commands/list_inspectors.rb b/lib/pry/commands/list_inspectors.rb
index 41854a23..eefab994 100644
--- a/lib/pry/commands/list_inspectors.rb
+++ b/lib/pry/commands/list_inspectors.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ListInspectors < Pry::ClassCommand
diff --git a/lib/pry/commands/ls.rb b/lib/pry/commands/ls.rb
index 5f15c8fa..1a03db15 100644
--- a/lib/pry/commands/ls.rb
+++ b/lib/pry/commands/ls.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/constants.rb b/lib/pry/commands/ls/constants.rb
index a07ff896..c0f50458 100644
--- a/lib/pry/commands/ls/constants.rb
+++ b/lib/pry/commands/ls/constants.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/formatter.rb b/lib/pry/commands/ls/formatter.rb
index 8b0ae6b6..c5163ca5 100644
--- a/lib/pry/commands/ls/formatter.rb
+++ b/lib/pry/commands/ls/formatter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/globals.rb b/lib/pry/commands/ls/globals.rb
index 77505be8..ab5c979d 100644
--- a/lib/pry/commands/ls/globals.rb
+++ b/lib/pry/commands/ls/globals.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/grep.rb b/lib/pry/commands/ls/grep.rb
index e13aea68..425670e4 100644
--- a/lib/pry/commands/ls/grep.rb
+++ b/lib/pry/commands/ls/grep.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/instance_vars.rb b/lib/pry/commands/ls/instance_vars.rb
index b5496ff2..9a35a359 100644
--- a/lib/pry/commands/ls/instance_vars.rb
+++ b/lib/pry/commands/ls/instance_vars.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/interrogatable.rb b/lib/pry/commands/ls/interrogatable.rb
index 67a43373..390cfd11 100644
--- a/lib/pry/commands/ls/interrogatable.rb
+++ b/lib/pry/commands/ls/interrogatable.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/jruby_hacks.rb b/lib/pry/commands/ls/jruby_hacks.rb
index 656fbd84..b631dbb4 100644
--- a/lib/pry/commands/ls/jruby_hacks.rb
+++ b/lib/pry/commands/ls/jruby_hacks.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/local_names.rb b/lib/pry/commands/ls/local_names.rb
index 8a2650d0..3f7c5faf 100644
--- a/lib/pry/commands/ls/local_names.rb
+++ b/lib/pry/commands/ls/local_names.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/local_vars.rb b/lib/pry/commands/ls/local_vars.rb
index 2b8f4374..45605e69 100644
--- a/lib/pry/commands/ls/local_vars.rb
+++ b/lib/pry/commands/ls/local_vars.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/ls_entity.rb b/lib/pry/commands/ls/ls_entity.rb
index 863ad876..197070a1 100644
--- a/lib/pry/commands/ls/ls_entity.rb
+++ b/lib/pry/commands/ls/ls_entity.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/methods.rb b/lib/pry/commands/ls/methods.rb
index f8aaeda1..484f6647 100644
--- a/lib/pry/commands/ls/methods.rb
+++ b/lib/pry/commands/ls/methods.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/methods_helper.rb b/lib/pry/commands/ls/methods_helper.rb
index 7ba52932..635cd214 100644
--- a/lib/pry/commands/ls/methods_helper.rb
+++ b/lib/pry/commands/ls/methods_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/ls/self_methods.rb b/lib/pry/commands/ls/self_methods.rb
index 5824926a..a8bf8a4a 100644
--- a/lib/pry/commands/ls/self_methods.rb
+++ b/lib/pry/commands/ls/self_methods.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Ls < Pry::ClassCommand
diff --git a/lib/pry/commands/nesting.rb b/lib/pry/commands/nesting.rb
index 5abe207b..93da1572 100644
--- a/lib/pry/commands/nesting.rb
+++ b/lib/pry/commands/nesting.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Nesting < Pry::ClassCommand
diff --git a/lib/pry/commands/play.rb b/lib/pry/commands/play.rb
index 57d22c10..e68b2e15 100644
--- a/lib/pry/commands/play.rb
+++ b/lib/pry/commands/play.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Play < Pry::ClassCommand
diff --git a/lib/pry/commands/pry_backtrace.rb b/lib/pry/commands/pry_backtrace.rb
index 559096fc..44b6e3b7 100644
--- a/lib/pry/commands/pry_backtrace.rb
+++ b/lib/pry/commands/pry_backtrace.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class PryBacktrace < Pry::ClassCommand
diff --git a/lib/pry/commands/pry_version.rb b/lib/pry/commands/pry_version.rb
index 3784a4c8..40408733 100644
--- a/lib/pry/commands/pry_version.rb
+++ b/lib/pry/commands/pry_version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Version < Pry::ClassCommand
diff --git a/lib/pry/commands/raise_up.rb b/lib/pry/commands/raise_up.rb
index 54510266..f002636e 100644
--- a/lib/pry/commands/raise_up.rb
+++ b/lib/pry/commands/raise_up.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # N.B. using a regular expresion here so that "raise-up 'foo'" does the right thing.
   class Command
diff --git a/lib/pry/commands/reload_code.rb b/lib/pry/commands/reload_code.rb
index 66264854..85f4260d 100644
--- a/lib/pry/commands/reload_code.rb
+++ b/lib/pry/commands/reload_code.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ReloadCode < Pry::ClassCommand
diff --git a/lib/pry/commands/reset.rb b/lib/pry/commands/reset.rb
index 91599b64..e668e59f 100644
--- a/lib/pry/commands/reset.rb
+++ b/lib/pry/commands/reset.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Reset < Pry::ClassCommand
diff --git a/lib/pry/commands/ri.rb b/lib/pry/commands/ri.rb
index 48cbf0cb..b9cb5907 100644
--- a/lib/pry/commands/ri.rb
+++ b/lib/pry/commands/ri.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'stringio'
 
 class Pry
diff --git a/lib/pry/commands/save_file.rb b/lib/pry/commands/save_file.rb
index 1f91a99c..3a6ecd5d 100644
--- a/lib/pry/commands/save_file.rb
+++ b/lib/pry/commands/save_file.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class SaveFile < Pry::ClassCommand
diff --git a/lib/pry/commands/shell_command.rb b/lib/pry/commands/shell_command.rb
index f12dea02..7b868607 100644
--- a/lib/pry/commands/shell_command.rb
+++ b/lib/pry/commands/shell_command.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ShellCommand < Pry::ClassCommand
diff --git a/lib/pry/commands/shell_mode.rb b/lib/pry/commands/shell_mode.rb
index 011a6fd3..a71adb94 100644
--- a/lib/pry/commands/shell_mode.rb
+++ b/lib/pry/commands/shell_mode.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ShellMode < Pry::ClassCommand
diff --git a/lib/pry/commands/show_doc.rb b/lib/pry/commands/show_doc.rb
index 40e558a9..c0f183b2 100644
--- a/lib/pry/commands/show_doc.rb
+++ b/lib/pry/commands/show_doc.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ShowDoc < Command::ShowInfo
diff --git a/lib/pry/commands/show_info.rb b/lib/pry/commands/show_info.rb
index 2f78d0c3..4e982af8 100644
--- a/lib/pry/commands/show_info.rb
+++ b/lib/pry/commands/show_info.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ShowInfo < Pry::ClassCommand
diff --git a/lib/pry/commands/show_input.rb b/lib/pry/commands/show_input.rb
index 176808c3..bc44806f 100644
--- a/lib/pry/commands/show_input.rb
+++ b/lib/pry/commands/show_input.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ShowInput < Pry::ClassCommand
diff --git a/lib/pry/commands/show_source.rb b/lib/pry/commands/show_source.rb
index 9390fb10..7df865c6 100644
--- a/lib/pry/commands/show_source.rb
+++ b/lib/pry/commands/show_source.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ShowSource < Command::ShowInfo
diff --git a/lib/pry/commands/stat.rb b/lib/pry/commands/stat.rb
index 2c22f32a..055242a5 100644
--- a/lib/pry/commands/stat.rb
+++ b/lib/pry/commands/stat.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Stat < Pry::ClassCommand
diff --git a/lib/pry/commands/switch_to.rb b/lib/pry/commands/switch_to.rb
index 84510701..448f2cd3 100644
--- a/lib/pry/commands/switch_to.rb
+++ b/lib/pry/commands/switch_to.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class SwitchTo < Pry::ClassCommand
diff --git a/lib/pry/commands/toggle_color.rb b/lib/pry/commands/toggle_color.rb
index b254d8e9..67d8a8ca 100644
--- a/lib/pry/commands/toggle_color.rb
+++ b/lib/pry/commands/toggle_color.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class ToggleColor < Pry::ClassCommand
diff --git a/lib/pry/commands/watch_expression.rb b/lib/pry/commands/watch_expression.rb
index 95a41432..f732a53f 100644
--- a/lib/pry/commands/watch_expression.rb
+++ b/lib/pry/commands/watch_expression.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class WatchExpression < Pry::ClassCommand
diff --git a/lib/pry/commands/watch_expression/expression.rb b/lib/pry/commands/watch_expression/expression.rb
index ee0ff457..3b0d605a 100644
--- a/lib/pry/commands/watch_expression/expression.rb
+++ b/lib/pry/commands/watch_expression/expression.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class WatchExpression
diff --git a/lib/pry/commands/whereami.rb b/lib/pry/commands/whereami.rb
index a8b589cb..5adc187a 100644
--- a/lib/pry/commands/whereami.rb
+++ b/lib/pry/commands/whereami.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'method_source'
 
 class Pry
diff --git a/lib/pry/commands/wtf.rb b/lib/pry/commands/wtf.rb
index 3ce86265..3e25dca3 100644
--- a/lib/pry/commands/wtf.rb
+++ b/lib/pry/commands/wtf.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Command
     class Wtf < Pry::ClassCommand
diff --git a/lib/pry/config.rb b/lib/pry/config.rb
index feeb4b40..18626363 100644
--- a/lib/pry/config.rb
+++ b/lib/pry/config.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'ostruct'
 
 class Pry
diff --git a/lib/pry/config/attributable.rb b/lib/pry/config/attributable.rb
index 4ff4e7cb..28391ef0 100644
--- a/lib/pry/config/attributable.rb
+++ b/lib/pry/config/attributable.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Config
     # Attributable provides the ability to create "attribute"
diff --git a/lib/pry/config/lazy_value.rb b/lib/pry/config/lazy_value.rb
index 8c2330ac..5b776068 100644
--- a/lib/pry/config/lazy_value.rb
+++ b/lib/pry/config/lazy_value.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Config
     # LazyValue is a Proc (block) wrapper. It is meant to be used as a
diff --git a/lib/pry/config/memoized_value.rb b/lib/pry/config/memoized_value.rb
index a8f61d15..670f45b9 100644
--- a/lib/pry/config/memoized_value.rb
+++ b/lib/pry/config/memoized_value.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Config
     # MemoizedValue is a Proc (block) wrapper. It is meant to be used as a
diff --git a/lib/pry/config/value.rb b/lib/pry/config/value.rb
index 3afec386..b646d97a 100644
--- a/lib/pry/config/value.rb
+++ b/lib/pry/config/value.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Config
     # Value holds a value for the given attribute and decides how it should
diff --git a/lib/pry/control_d_handler.rb b/lib/pry/control_d_handler.rb
index f9b93003..cee15ba5 100644
--- a/lib/pry/control_d_handler.rb
+++ b/lib/pry/control_d_handler.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # @api private
   # @since ?.?.?
diff --git a/lib/pry/core_extensions.rb b/lib/pry/core_extensions.rb
index 7d10e3eb..e5063a05 100644
--- a/lib/pry/core_extensions.rb
+++ b/lib/pry/core_extensions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # @return [Array] Code of the method used when implementing Pry's
   #   __binding__, along with line indication to be used with instance_eval (and
diff --git a/lib/pry/editor.rb b/lib/pry/editor.rb
index bf10d984..df3422a0 100644
--- a/lib/pry/editor.rb
+++ b/lib/pry/editor.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'shellwords'
 
 class Pry
diff --git a/lib/pry/exception_handler.rb b/lib/pry/exception_handler.rb
index 9b50fe80..3dddc6b5 100644
--- a/lib/pry/exception_handler.rb
+++ b/lib/pry/exception_handler.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # @api private
   # @since ?.?.?
diff --git a/lib/pry/exceptions.rb b/lib/pry/exceptions.rb
index bec48c28..eac1c009 100644
--- a/lib/pry/exceptions.rb
+++ b/lib/pry/exceptions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # As a REPL, we often want to catch any unexpected exceptions that may have
   # been raised; however we don't want to go overboard and prevent the user
diff --git a/lib/pry/forwardable.rb b/lib/pry/forwardable.rb
index 1e0674d4..3ae59a89 100644
--- a/lib/pry/forwardable.rb
+++ b/lib/pry/forwardable.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   module Forwardable
     require 'forwardable'
diff --git a/lib/pry/helpers.rb b/lib/pry/helpers.rb
index faaced9b..4bbbaafc 100644
--- a/lib/pry/helpers.rb
+++ b/lib/pry/helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "pry/helpers/base_helpers"
 require "pry/helpers/options_helpers"
 require "pry/helpers/command_helpers"
diff --git a/lib/pry/helpers/base_helpers.rb b/lib/pry/helpers/base_helpers.rb
index 5d75a50a..84d97616 100644
--- a/lib/pry/helpers/base_helpers.rb
+++ b/lib/pry/helpers/base_helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   module Helpers
     module BaseHelpers
diff --git a/lib/pry/helpers/command_helpers.rb b/lib/pry/helpers/command_helpers.rb
index 15798c64..374f6b20 100644
--- a/lib/pry/helpers/command_helpers.rb
+++ b/lib/pry/helpers/command_helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'tempfile'
 
 class Pry
diff --git a/lib/pry/helpers/documentation_helpers.rb b/lib/pry/helpers/documentation_helpers.rb
index b56d8e0d..1ce6be2b 100644
--- a/lib/pry/helpers/documentation_helpers.rb
+++ b/lib/pry/helpers/documentation_helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   module Helpers
     # This class contains methods useful for extracting
diff --git a/lib/pry/helpers/options_helpers.rb b/lib/pry/helpers/options_helpers.rb
index 4c31e9f0..1f93c8db 100644
--- a/lib/pry/helpers/options_helpers.rb
+++ b/lib/pry/helpers/options_helpers.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   module Helpers
     module OptionsHelpers
diff --git a/lib/pry/helpers/platform.rb b/lib/pry/helpers/platform.rb
index b7e98555..f4b3dccb 100644
--- a/lib/pry/helpers/platform.rb
+++ b/lib/pry/helpers/platform.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'rbconfig'
 
 class Pry
diff --git a/lib/pry/helpers/table.rb b/lib/pry/helpers/table.rb
index 6835fa50..59297f9c 100644
--- a/lib/pry/helpers/table.rb
+++ b/lib/pry/helpers/table.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   module Helpers
     def self.tablify_or_one_line(heading, things, config = Pry.config)
diff --git a/lib/pry/helpers/text.rb b/lib/pry/helpers/text.rb
index cefeb234..b1fee03f 100644
--- a/lib/pry/helpers/text.rb
+++ b/lib/pry/helpers/text.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   module Helpers
     # The methods defined on {Text} are available to custom commands via
diff --git a/lib/pry/history.rb b/lib/pry/history.rb
index 7200a69d..19e90454 100644
--- a/lib/pry/history.rb
+++ b/lib/pry/history.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # The History class is responsible for maintaining the user's input history,
   # both internally and within Readline.
diff --git a/lib/pry/hooks.rb b/lib/pry/hooks.rb
index 38d70281..47ffd97f 100644
--- a/lib/pry/hooks.rb
+++ b/lib/pry/hooks.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # Implements a hooks system for Pry. A hook is a callable that is associated
   # with an event. A number of events are currently provided by Pry, these
diff --git a/lib/pry/indent.rb b/lib/pry/indent.rb
index c56d032b..306c82d0 100644
--- a/lib/pry/indent.rb
+++ b/lib/pry/indent.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   ##
   # Pry::Indent is a class that can be used to indent a number of lines
diff --git a/lib/pry/input_completer.rb b/lib/pry/input_completer.rb
index 1b54613d..16d55fb1 100644
--- a/lib/pry/input_completer.rb
+++ b/lib/pry/input_completer.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # taken from irb
 # Implements tab completion for Readline in Pry
 class Pry
diff --git a/lib/pry/input_lock.rb b/lib/pry/input_lock.rb
index a1dbc259..806dd53e 100644
--- a/lib/pry/input_lock.rb
+++ b/lib/pry/input_lock.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # There is one InputLock per input (such as STDIN) as two REPLs on the same
   # input makes things delirious. InputLock serializes accesses to the input so
diff --git a/lib/pry/inspector.rb b/lib/pry/inspector.rb
index ee993018..6e8a692c 100644
--- a/lib/pry/inspector.rb
+++ b/lib/pry/inspector.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Inspector
     MAP = {
diff --git a/lib/pry/last_exception.rb b/lib/pry/last_exception.rb
index 61cb3844..4cc0f56b 100644
--- a/lib/pry/last_exception.rb
+++ b/lib/pry/last_exception.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 #
 # {Pry::LastException} is a proxy class who wraps an Exception object for
 # {Pry#last_exception}. it extends the exception object with methods that
diff --git a/lib/pry/method.rb b/lib/pry/method.rb
index 3301ae6f..aefe61ac 100644
--- a/lib/pry/method.rb
+++ b/lib/pry/method.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'method_source'
 
 class Pry
diff --git a/lib/pry/method/disowned.rb b/lib/pry/method/disowned.rb
index 411bdd95..477e596a 100644
--- a/lib/pry/method/disowned.rb
+++ b/lib/pry/method/disowned.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Method
     # A Disowned Method is one that's been removed from the class on which it was defined.
diff --git a/lib/pry/method/patcher.rb b/lib/pry/method/patcher.rb
index f0b93837..656039d0 100644
--- a/lib/pry/method/patcher.rb
+++ b/lib/pry/method/patcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Method
     class Patcher
diff --git a/lib/pry/method/weird_method_locator.rb b/lib/pry/method/weird_method_locator.rb
index d559f36f..e4f58c8f 100644
--- a/lib/pry/method/weird_method_locator.rb
+++ b/lib/pry/method/weird_method_locator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Method
     # This class is responsible for locating the *real* `Pry::Method`
diff --git a/lib/pry/object_path.rb b/lib/pry/object_path.rb
index 90f994b0..b200c2bb 100644
--- a/lib/pry/object_path.rb
+++ b/lib/pry/object_path.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'strscan'
 
 class Pry
diff --git a/lib/pry/output.rb b/lib/pry/output.rb
index c6bc784b..6ecd8752 100644
--- a/lib/pry/output.rb
+++ b/lib/pry/output.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Output
     attr_reader :pry_instance
diff --git a/lib/pry/pager.rb b/lib/pry/pager.rb
index 4ebdcb66..966e06c1 100644
--- a/lib/pry/pager.rb
+++ b/lib/pry/pager.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # A pager is an `IO`-like object that accepts text and either prints it
 # immediately, prints it one page at a time, or streams it to an external
 # program to print one page at a time.
diff --git a/lib/pry/plugins.rb b/lib/pry/plugins.rb
index 56a1bed8..c29894d4 100644
--- a/lib/pry/plugins.rb
+++ b/lib/pry/plugins.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'ostruct'
 
 class Pry
diff --git a/lib/pry/prompt.rb b/lib/pry/prompt.rb
index 1e47174f..656e4e2e 100644
--- a/lib/pry/prompt.rb
+++ b/lib/pry/prompt.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # Prompt represents the Pry prompt, which can be used with Readline-like
   # libraries. It defines a few default prompts (default prompt, simple prompt,
diff --git a/lib/pry/pry_class.rb b/lib/pry/pry_class.rb
index e2ca9b38..3e8792c8 100644
--- a/lib/pry/pry_class.rb
+++ b/lib/pry/pry_class.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'stringio'
 require 'pathname'
 
diff --git a/lib/pry/pry_instance.rb b/lib/pry/pry_instance.rb
index 41eddb78..b46e703d 100644
--- a/lib/pry/pry_instance.rb
+++ b/lib/pry/pry_instance.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'method_source'
 require 'ostruct'
 
diff --git a/lib/pry/repl.rb b/lib/pry/repl.rb
index 7c408407..d226641b 100644
--- a/lib/pry/repl.rb
+++ b/lib/pry/repl.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class REPL
     extend Pry::Forwardable
diff --git a/lib/pry/repl_file_loader.rb b/lib/pry/repl_file_loader.rb
index 57942119..3a06fe7a 100644
--- a/lib/pry/repl_file_loader.rb
+++ b/lib/pry/repl_file_loader.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # A class to manage the loading of files through the REPL loop.
   # This is an interesting trick as it processes your file as if it
diff --git a/lib/pry/ring.rb b/lib/pry/ring.rb
index e40248ff..a61d077a 100644
--- a/lib/pry/ring.rb
+++ b/lib/pry/ring.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # A ring is a thread-safe fixed-capacity array to which you can only add
   # elements. Older entries are overwritten as you add new elements, so that the
diff --git a/lib/pry/slop.rb b/lib/pry/slop.rb
index 6fda3971..bf51f5a1 100644
--- a/lib/pry/slop.rb
+++ b/lib/pry/slop.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # rubocop:disable Metrics/ClassLength
   class Slop
diff --git a/lib/pry/slop/commands.rb b/lib/pry/slop/commands.rb
index f320c4cc..4c254270 100644
--- a/lib/pry/slop/commands.rb
+++ b/lib/pry/slop/commands.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Slop
     class Commands
diff --git a/lib/pry/slop/option.rb b/lib/pry/slop/option.rb
index fc77ba32..8a0df7e1 100644
--- a/lib/pry/slop/option.rb
+++ b/lib/pry/slop/option.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Slop
     class Option
diff --git a/lib/pry/syntax_highlighter.rb b/lib/pry/syntax_highlighter.rb
index 3eb0dd5b..f7f3375b 100644
--- a/lib/pry/syntax_highlighter.rb
+++ b/lib/pry/syntax_highlighter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'coderay'
 
 class Pry
diff --git a/lib/pry/system_command_handler.rb b/lib/pry/system_command_handler.rb
index 24bea2e3..fcbfeb57 100644
--- a/lib/pry/system_command_handler.rb
+++ b/lib/pry/system_command_handler.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # @api private
   # @since ?.?.?
diff --git a/lib/pry/terminal.rb b/lib/pry/terminal.rb
index 59a13f41..c09c6178 100644
--- a/lib/pry/terminal.rb
+++ b/lib/pry/terminal.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class Terminal
     class << self
diff --git a/lib/pry/testable.rb b/lib/pry/testable.rb
index 5dbb9269..e3bafc22 100644
--- a/lib/pry/testable.rb
+++ b/lib/pry/testable.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # good idea ???
 # if you're testing pry plugin you should require pry by yourself, no?
 require 'pry' unless defined?(Pry)
diff --git a/lib/pry/testable/evalable.rb b/lib/pry/testable/evalable.rb
index 08f68a35..36d3aa81 100644
--- a/lib/pry/testable/evalable.rb
+++ b/lib/pry/testable/evalable.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   module Testable
     module Evalable
diff --git a/lib/pry/testable/mockable.rb b/lib/pry/testable/mockable.rb
index bc88c92b..49581163 100644
--- a/lib/pry/testable/mockable.rb
+++ b/lib/pry/testable/mockable.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'stringio'
 
 class Pry
diff --git a/lib/pry/testable/pry_tester.rb b/lib/pry/testable/pry_tester.rb
index 73a6e845..55f0b558 100644
--- a/lib/pry/testable/pry_tester.rb
+++ b/lib/pry/testable/pry_tester.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'stringio'
 
 class Pry
diff --git a/lib/pry/testable/utility.rb b/lib/pry/testable/utility.rb
index 8403d1df..4c358c88 100644
--- a/lib/pry/testable/utility.rb
+++ b/lib/pry/testable/utility.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'tempfile'
 
 class Pry
diff --git a/lib/pry/testable/variables.rb b/lib/pry/testable/variables.rb
index ba285682..deb156b6 100644
--- a/lib/pry/testable/variables.rb
+++ b/lib/pry/testable/variables.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   module Testable
     module Variables
diff --git a/lib/pry/version.rb b/lib/pry/version.rb
index 4dbb7254..231d89d9 100644
--- a/lib/pry/version.rb
+++ b/lib/pry/version.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   VERSION = '0.12.2'.freeze
 end
diff --git a/lib/pry/warning.rb b/lib/pry/warning.rb
index 5585ce20..b37478f4 100644
--- a/lib/pry/warning.rb
+++ b/lib/pry/warning.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   # @api private
   # @since ?.?.?
diff --git a/lib/pry/wrapped_module.rb b/lib/pry/wrapped_module.rb
index 8261b3fb..c07ba682 100644
--- a/lib/pry/wrapped_module.rb
+++ b/lib/pry/wrapped_module.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class << self
     # If the given object is a `Pry::WrappedModule`, return it unaltered. If it's
diff --git a/lib/pry/wrapped_module/candidate.rb b/lib/pry/wrapped_module/candidate.rb
index a84e7ba3..509b75bc 100644
--- a/lib/pry/wrapped_module/candidate.rb
+++ b/lib/pry/wrapped_module/candidate.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Pry
   class WrappedModule
     # This class represents a single candidate for a module/class definition.
diff --git a/pry.gemspec b/pry.gemspec
index 23901106..d5acfb5d 100644
--- a/pry.gemspec
+++ b/pry.gemspec
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require File.expand_path('../lib/pry/version', __FILE__)
 
 Gem::Specification.new do |s|
diff --git a/spec/block_command_spec.rb b/spec/block_command_spec.rb
index 1a57e96a..915cbe58 100644
--- a/spec/block_command_spec.rb
+++ b/spec/block_command_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::BlockCommand do
   subject { Class.new(described_class).new }
 
diff --git a/spec/class_command_spec.rb b/spec/class_command_spec.rb
index 8d7d7484..59151d62 100644
--- a/spec/class_command_spec.rb
+++ b/spec/class_command_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::ClassCommand do
   describe ".inherited" do
     context "when match is defined" do
diff --git a/spec/cli_spec.rb b/spec/cli_spec.rb
index b9c8ee46..93625f79 100644
--- a/spec/cli_spec.rb
+++ b/spec/cli_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::CLI do
   before { described_class.reset }
 
diff --git a/spec/code_object_spec.rb b/spec/code_object_spec.rb
index 8cee8b66..ef670e00 100644
--- a/spec/code_object_spec.rb
+++ b/spec/code_object_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::CodeObject do
   let(:pry) do
     Pry.new.tap { |p| p.binding_stack = [binding] }
diff --git a/spec/code_spec.rb b/spec/code_spec.rb
index 0d2c2d4d..4ae2ca0b 100644
--- a/spec/code_spec.rb
+++ b/spec/code_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'method_source'
 require 'tempfile'
 
diff --git a/spec/color_printer_spec.rb b/spec/color_printer_spec.rb
index 8347a348..3c9048ec 100644
--- a/spec/color_printer_spec.rb
+++ b/spec/color_printer_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::ColorPrinter do
   let(:output) { StringIO.new }
 
diff --git a/spec/command_integration_spec.rb b/spec/command_integration_spec.rb
index 98e799a4..c1b63052 100644
--- a/spec/command_integration_spec.rb
+++ b/spec/command_integration_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "commands" do
   before do
     @str_output = StringIO.new
diff --git a/spec/command_set_spec.rb b/spec/command_set_spec.rb
index 1cc381d6..fc67d140 100644
--- a/spec/command_set_spec.rb
+++ b/spec/command_set_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::CommandSet do
   let(:set) do
     Pry::CommandSet.new { import(Pry::Commands) }
diff --git a/spec/command_spec.rb b/spec/command_spec.rb
index 56ee27b3..b676be81 100644
--- a/spec/command_spec.rb
+++ b/spec/command_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'stringio'
 
 RSpec.describe Pry::Command do
diff --git a/spec/command_state_spec.rb b/spec/command_state_spec.rb
index 10097b2b..264b772c 100644
--- a/spec/command_state_spec.rb
+++ b/spec/command_state_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::CommandState do
   describe ".default" do
     it "returns the default command state" do
diff --git a/spec/commands/amend_line_spec.rb b/spec/commands/amend_line_spec.rb
index 29b68f80..edf50f23 100644
--- a/spec/commands/amend_line_spec.rb
+++ b/spec/commands/amend_line_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "amend-line" do
   before do
     @t = pry_tester
diff --git a/spec/commands/bang_spec.rb b/spec/commands/bang_spec.rb
index d48bd6da..e07964ec 100644
--- a/spec/commands/bang_spec.rb
+++ b/spec/commands/bang_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "!" do
   before do
     @t = pry_tester
diff --git a/spec/commands/cat/file_formatter_spec.rb b/spec/commands/cat/file_formatter_spec.rb
index a255a54f..4360f071 100644
--- a/spec/commands/cat/file_formatter_spec.rb
+++ b/spec/commands/cat/file_formatter_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry::Command::Cat::FileFormatter do
   before do
     @p   = Pry.new
diff --git a/spec/commands/cat_spec.rb b/spec/commands/cat_spec.rb
index a2c3ecba..8ed3ed8a 100644
--- a/spec/commands/cat_spec.rb
+++ b/spec/commands/cat_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'tempfile'
 
 describe "cat" do
diff --git a/spec/commands/cd_spec.rb b/spec/commands/cd_spec.rb
index 5ea64861..9777bddb 100644
--- a/spec/commands/cd_spec.rb
+++ b/spec/commands/cd_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe 'cd' do
   before do
     @o = Object.new
diff --git a/spec/commands/clear_screen_spec.rb b/spec/commands/clear_screen_spec.rb
index 152201d2..663e3717 100644
--- a/spec/commands/clear_screen_spec.rb
+++ b/spec/commands/clear_screen_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe "clear-screen" do
   before do
     @t = pry_tester
diff --git a/spec/commands/disable_pry_spec.rb b/spec/commands/disable_pry_spec.rb
index af5fa80a..db90a5cc 100644
--- a/spec/commands/disable_pry_spec.rb
+++ b/spec/commands/disable_pry_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "disable-pry" do
   before do
     @t = pry_tester
diff --git a/spec/commands/edit_spec.rb b/spec/commands/edit_spec.rb
index cc741053..925a9425 100644
--- a/spec/commands/edit_spec.rb
+++ b/spec/commands/edit_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'pathname'
 require 'tempfile'
 
diff --git a/spec/commands/exit_all_spec.rb b/spec/commands/exit_all_spec.rb
index 640fa17f..aa3c705b 100644
--- a/spec/commands/exit_all_spec.rb
+++ b/spec/commands/exit_all_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "exit-all" do
   before { @pry = Pry.new }
 
diff --git a/spec/commands/exit_program_spec.rb b/spec/commands/exit_program_spec.rb
index dcb2bb71..58bda763 100644
--- a/spec/commands/exit_program_spec.rb
+++ b/spec/commands/exit_program_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "exit-program" do
   it 'should raise SystemExit' do
     expect { pry_eval('exit-program') }.to raise_error SystemExit
diff --git a/spec/commands/exit_spec.rb b/spec/commands/exit_spec.rb
index 2b4da7e5..3bbf5f5c 100644
--- a/spec/commands/exit_spec.rb
+++ b/spec/commands/exit_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "exit" do
   before { @pry = Pry.new(target: :outer, output: StringIO.new) }
 
diff --git a/spec/commands/find_method_spec.rb b/spec/commands/find_method_spec.rb
index f584f3b5..7be22752 100644
--- a/spec/commands/find_method_spec.rb
+++ b/spec/commands/find_method_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "find-method" do
   MyKlass = Class.new do
     def hello
diff --git a/spec/commands/help_spec.rb b/spec/commands/help_spec.rb
index 59e451c9..0e748a00 100644
--- a/spec/commands/help_spec.rb
+++ b/spec/commands/help_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "help" do
   before do
     @oldset = Pry.config.commands
diff --git a/spec/commands/hist_spec.rb b/spec/commands/hist_spec.rb
index 558b4f99..2fbbffb6 100644
--- a/spec/commands/hist_spec.rb
+++ b/spec/commands/hist_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "hist" do
   before do
     Pry.history.clear
diff --git a/spec/commands/jump_to_spec.rb b/spec/commands/jump_to_spec.rb
index 48c82f5f..c8f8f5c7 100644
--- a/spec/commands/jump_to_spec.rb
+++ b/spec/commands/jump_to_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe "jump-to" do
   let(:obj) { Object.new }
 
diff --git a/spec/commands/ls_spec.rb b/spec/commands/ls_spec.rb
index e147f726..f3ef8f9b 100644
--- a/spec/commands/ls_spec.rb
+++ b/spec/commands/ls_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "ls" do
   describe "bug #1407" do
     it "behaves as usual when a method of the same name exists." do
diff --git a/spec/commands/play_spec.rb b/spec/commands/play_spec.rb
index f82bc645..000f6fe5 100644
--- a/spec/commands/play_spec.rb
+++ b/spec/commands/play_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # This command needs a TONNE more tests for it, but i can't figure out
 # how to do them yet, and i really want to release. Sorry. Someone
 # come along and do a better job.
diff --git a/spec/commands/raise_up_spec.rb b/spec/commands/raise_up_spec.rb
index 39b2f127..dbb45f91 100644
--- a/spec/commands/raise_up_spec.rb
+++ b/spec/commands/raise_up_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "raise-up" do
   before do
     @self  = "Pad.self = self"
diff --git a/spec/commands/reload_code_spec.rb b/spec/commands/reload_code_spec.rb
index b7fe743f..845ee117 100644
--- a/spec/commands/reload_code_spec.rb
+++ b/spec/commands/reload_code_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "reload_code" do
   describe "reload_current_file" do
     it 'raises an error source code not found' do
diff --git a/spec/commands/ri_command_spec.rb b/spec/commands/ri_command_spec.rb
index 9fc4468a..0429019d 100644
--- a/spec/commands/ri_command_spec.rb
+++ b/spec/commands/ri_command_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "ri" do
   it "prints an error message without an argument" do
     expect(pry_eval("ri")).to include(
diff --git a/spec/commands/save_file_spec.rb b/spec/commands/save_file_spec.rb
index 902ac926..9dd80966 100644
--- a/spec/commands/save_file_spec.rb
+++ b/spec/commands/save_file_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'tempfile'
 
 describe "save-file" do
diff --git a/spec/commands/shell_command_spec.rb b/spec/commands/shell_command_spec.rb
index 62526b3c..f66207b4 100644
--- a/spec/commands/shell_command_spec.rb
+++ b/spec/commands/shell_command_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry::Command::ShellCommand do
   describe 'cd' do
     before do
diff --git a/spec/commands/show_doc_spec.rb b/spec/commands/show_doc_spec.rb
index e0bba4da..67ce1bc9 100644
--- a/spec/commands/show_doc_spec.rb
+++ b/spec/commands/show_doc_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "fixtures/show_source_doc_examples"
 
 describe "show-doc" do
diff --git a/spec/commands/show_input_spec.rb b/spec/commands/show_input_spec.rb
index 8fc82b3a..3953dbf3 100644
--- a/spec/commands/show_input_spec.rb
+++ b/spec/commands/show_input_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "show-input" do
   before do
     @t = pry_tester
diff --git a/spec/commands/show_source_spec.rb b/spec/commands/show_source_spec.rb
index 13bb86e9..fc921a9d 100644
--- a/spec/commands/show_source_spec.rb
+++ b/spec/commands/show_source_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "fixtures/show_source_doc_examples"
 
 describe "show-source" do
diff --git a/spec/commands/watch_expression_spec.rb b/spec/commands/watch_expression_spec.rb
index 04f26d10..08f3d107 100644
--- a/spec/commands/watch_expression_spec.rb
+++ b/spec/commands/watch_expression_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "watch expression" do
   # Custom eval that will:
   # 1) Create an instance of pry that can use for multiple calls
diff --git a/spec/commands/whereami_spec.rb b/spec/commands/whereami_spec.rb
index 1ccac2ef..aff868ce 100644
--- a/spec/commands/whereami_spec.rb
+++ b/spec/commands/whereami_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'method_source'
 
 describe "whereami" do
diff --git a/spec/commands/wtf_spec.rb b/spec/commands/wtf_spec.rb
index 0a224fa5..ace8cbf3 100644
--- a/spec/commands/wtf_spec.rb
+++ b/spec/commands/wtf_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "wtf?!" do
   let(:tester) do
     pry_tester do
diff --git a/spec/completion_spec.rb b/spec/completion_spec.rb
index 4216ea74..5df577f5 100644
--- a/spec/completion_spec.rb
+++ b/spec/completion_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "readline" unless defined?(Readline)
 require "pry/input_completer"
 
diff --git a/spec/config/attributable_spec.rb b/spec/config/attributable_spec.rb
index c0c2b167..9b6ea561 100644
--- a/spec/config/attributable_spec.rb
+++ b/spec/config/attributable_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::Config::Attributable do
   subject { klass.new }
 
diff --git a/spec/config/lazy_value_spec.rb b/spec/config/lazy_value_spec.rb
index dc2aaa1e..7b9f28f3 100644
--- a/spec/config/lazy_value_spec.rb
+++ b/spec/config/lazy_value_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::Config::LazyValue do
   describe "#call" do
     subject { described_class.new { rand } }
diff --git a/spec/config/memoized_value_spec.rb b/spec/config/memoized_value_spec.rb
index 1601bff2..22e278dc 100644
--- a/spec/config/memoized_value_spec.rb
+++ b/spec/config/memoized_value_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::Config::MemoizedValue do
   describe "#call" do
     subject { described_class.new { rand } }
diff --git a/spec/config/value_spec.rb b/spec/config/value_spec.rb
index efb8eca4..7ddd0151 100644
--- a/spec/config/value_spec.rb
+++ b/spec/config/value_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::Config::Value do
   describe "#call" do
     context "when given value is a MemoizedValue" do
diff --git a/spec/config_spec.rb b/spec/config_spec.rb
index 13aa52aa..d42d4d1e 100644
--- a/spec/config_spec.rb
+++ b/spec/config_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::Config do
   specify { expect(subject.input).to respond_to(:readline) }
   specify { expect(subject.output).to be_an(IO) }
diff --git a/spec/control_d_handler_spec.rb b/spec/control_d_handler_spec.rb
index 030cefd6..1306bdc3 100644
--- a/spec/control_d_handler_spec.rb
+++ b/spec/control_d_handler_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::ControlDHandler do
   context "when given eval string is non-empty" do
     let(:pry_instance) do
diff --git a/spec/documentation_helper_spec.rb b/spec/documentation_helper_spec.rb
index c6395774..8da62a29 100644
--- a/spec/documentation_helper_spec.rb
+++ b/spec/documentation_helper_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry::Helpers::DocumentationHelpers do
   before do
     @helper = Pry::Helpers::DocumentationHelpers
diff --git a/spec/editor_spec.rb b/spec/editor_spec.rb
index ea4c31d7..3410cbe7 100644
--- a/spec/editor_spec.rb
+++ b/spec/editor_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'pathname'
 
 describe Pry::Editor do
diff --git a/spec/exception_handler_spec.rb b/spec/exception_handler_spec.rb
index 62138153..b1608509 100644
--- a/spec/exception_handler_spec.rb
+++ b/spec/exception_handler_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::ExceptionHandler do
   describe ".handle_exception" do
     let(:output) { StringIO.new }
diff --git a/spec/fixtures/Gemfile b/spec/fixtures/Gemfile
index 20b4d4ae..ebc45888 100644
--- a/spec/fixtures/Gemfile
+++ b/spec/fixtures/Gemfile
@@ -1 +1,3 @@
+# frozen_string_literal: true
+
 source 'https://rubygems.org'
diff --git a/spec/fixtures/candidate_helper1.rb b/spec/fixtures/candidate_helper1.rb
index 7833d52f..ec431807 100644
--- a/spec/fixtures/candidate_helper1.rb
+++ b/spec/fixtures/candidate_helper1.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # rank 0
 class CandidateTest
   def test1; end
diff --git a/spec/fixtures/candidate_helper2.rb b/spec/fixtures/candidate_helper2.rb
index 9de72c8d..06bb0475 100644
--- a/spec/fixtures/candidate_helper2.rb
+++ b/spec/fixtures/candidate_helper2.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # rank 1
 class CandidateTest
   def test4; end
diff --git a/spec/fixtures/show_source_doc_examples.rb b/spec/fixtures/show_source_doc_examples.rb
index bb24960c..dad53e06 100644
--- a/spec/fixtures/show_source_doc_examples.rb
+++ b/spec/fixtures/show_source_doc_examples.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # used by show_source_spec.rb and show_doc_spec.rb
 class TestClassForShowSource
   # doc
diff --git a/spec/fixtures/whereami_helper.rb b/spec/fixtures/whereami_helper.rb
index 6aea145e..be6d28bb 100644
--- a/spec/fixtures/whereami_helper.rb
+++ b/spec/fixtures/whereami_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # rubocop:disable Layout/EmptyLineBetweenDefs
 class Cor
   def a; end
diff --git a/spec/helpers/command_helpers_spec.rb b/spec/helpers/command_helpers_spec.rb
index 0e696cc5..7cc8f53d 100644
--- a/spec/helpers/command_helpers_spec.rb
+++ b/spec/helpers/command_helpers_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::Helpers::CommandHelpers do
   describe "#temp_file" do
     it "yields a tempfile" do
diff --git a/spec/helpers/table_spec.rb b/spec/helpers/table_spec.rb
index 8aceac9c..66b3acfa 100644
--- a/spec/helpers/table_spec.rb
+++ b/spec/helpers/table_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe 'Formatting Table' do
   it 'knows about colorized fitting' do
     t = Pry::Helpers::Table.new %w[hihi], column_count: 1
diff --git a/spec/history_spec.rb b/spec/history_spec.rb
index 43bf55a2..32eadfb3 100644
--- a/spec/history_spec.rb
+++ b/spec/history_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'tempfile'
 require 'rbconfig'
 
diff --git a/spec/hooks_spec.rb b/spec/hooks_spec.rb
index 465ed236..0b8d6f9c 100644
--- a/spec/hooks_spec.rb
+++ b/spec/hooks_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry::Hooks do
   before do
     @hooks = Pry::Hooks.new
diff --git a/spec/indent_spec.rb b/spec/indent_spec.rb
index 24017441..aa48379f 100644
--- a/spec/indent_spec.rb
+++ b/spec/indent_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Please keep in mind that any hash signs ("#") in the heredoc strings are
 # placed on purpose. Without these editors might remove the whitespace on empty
 # lines.
diff --git a/spec/integration/bundler_spec.rb b/spec/integration/bundler_spec.rb
index 7b98822b..3e8d146f 100644
--- a/spec/integration/bundler_spec.rb
+++ b/spec/integration/bundler_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'rbconfig'
 
 RSpec.describe 'Bundler' do
diff --git a/spec/integration/cli_spec.rb b/spec/integration/cli_spec.rb
index 306dcd38..0ea2a12a 100644
--- a/spec/integration/cli_spec.rb
+++ b/spec/integration/cli_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'rbconfig'
 
 RSpec.describe 'The bin/pry CLI' do
diff --git a/spec/integration/hanami_spec.rb b/spec/integration/hanami_spec.rb
index 1541a623..5fae6ef8 100644
--- a/spec/integration/hanami_spec.rb
+++ b/spec/integration/hanami_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "shellwords"
 require 'rbconfig'
 
diff --git a/spec/integration/readline_spec.rb b/spec/integration/readline_spec.rb
index 1407ca57..aaec5d5e 100644
--- a/spec/integration/readline_spec.rb
+++ b/spec/integration/readline_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # These specs ensure that Pry doesn't require readline until the first time a
 # REPL is started.
 
diff --git a/spec/method/patcher_spec.rb b/spec/method/patcher_spec.rb
index 24524d02..98c96dd6 100644
--- a/spec/method/patcher_spec.rb
+++ b/spec/method/patcher_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry::Method::Patcher do
   # rubocop:disable Style/SingleLineMethods
   before do
diff --git a/spec/method_spec.rb b/spec/method_spec.rb
index 2d5a19f6..65ce0e96 100644
--- a/spec/method_spec.rb
+++ b/spec/method_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'set'
 
 describe Pry::Method do
diff --git a/spec/pager_spec.rb b/spec/pager_spec.rb
index 4df0aad6..9c61cb63 100644
--- a/spec/pager_spec.rb
+++ b/spec/pager_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "Pry::Pager" do
   describe "PageTracker" do
     before do
diff --git a/spec/prompt_spec.rb b/spec/prompt_spec.rb
index 58616cd5..04688d7e 100644
--- a/spec/prompt_spec.rb
+++ b/spec/prompt_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry::Prompt do
   describe ".[]" do
     it "accesses prompts" do
diff --git a/spec/pry_defaults_spec.rb b/spec/pry_defaults_spec.rb
index 24fa54c5..816481ff 100644
--- a/spec/pry_defaults_spec.rb
+++ b/spec/pry_defaults_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 _version = 1
 
 describe "test Pry defaults" do
diff --git a/spec/pry_output_spec.rb b/spec/pry_output_spec.rb
index 8f905d02..3850da62 100644
--- a/spec/pry_output_spec.rb
+++ b/spec/pry_output_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry do
   describe "output failsafe" do
     after { Pry.config.print = Pry::Config.new.print }
diff --git a/spec/pry_repl_spec.rb b/spec/pry_repl_spec.rb
index f407240a..946b92e8 100644
--- a/spec/pry_repl_spec.rb
+++ b/spec/pry_repl_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry::REPL do
   it "should let you run commands in the middle of multiline expressions" do
     ReplTester.start do
diff --git a/spec/pry_spec.rb b/spec/pry_spec.rb
index da73c275..c320a905 100644
--- a/spec/pry_spec.rb
+++ b/spec/pry_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry do
   before do
     @str_output = StringIO.new
diff --git a/spec/pryrc_spec.rb b/spec/pryrc_spec.rb
index 338f6b7e..a7b5fc2a 100644
--- a/spec/pryrc_spec.rb
+++ b/spec/pryrc_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry do
   describe 'loading rc files' do
     before do
diff --git a/spec/ring_spec.rb b/spec/ring_spec.rb
index 2f023461..4c7efbb5 100644
--- a/spec/ring_spec.rb
+++ b/spec/ring_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry::Ring do
   let(:ring) { described_class.new(3) }
 
diff --git a/spec/run_command_spec.rb b/spec/run_command_spec.rb
index af81d96a..8cbb8e14 100644
--- a/spec/run_command_spec.rb
+++ b/spec/run_command_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "Pry.run_command" do
   before do
     o = Object.new
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index b6111e27..c8315144 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 if ENV['COVERAGE']
   require 'simplecov'
   SimpleCov.start
diff --git a/spec/sticky_locals_spec.rb b/spec/sticky_locals_spec.rb
index 1fa75f87..ed6b29e0 100644
--- a/spec/sticky_locals_spec.rb
+++ b/spec/sticky_locals_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "Sticky locals (_file_ and friends)" do
   it 'locals should all exist upon initialization' do
     expect { pry_eval '_file_', '_dir_', '_ex_', 'pry_instance', '_' }
diff --git a/spec/support/mock_pry.rb b/spec/support/mock_pry.rb
index c7246111..555acee1 100644
--- a/spec/support/mock_pry.rb
+++ b/spec/support/mock_pry.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 def mock_pry(*args)
   args.flatten!
   binding = args.first.is_a?(Binding) ? args.shift : binding()
diff --git a/spec/support/repl_tester.rb b/spec/support/repl_tester.rb
index ea0419e7..b6e7585e 100644
--- a/spec/support/repl_tester.rb
+++ b/spec/support/repl_tester.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'delegate'
 
 # This is for super-high-level integration testing.
diff --git a/spec/syntax_checking_spec.rb b/spec/syntax_checking_spec.rb
index 9312c6a5..ec7f5b36 100644
--- a/spec/syntax_checking_spec.rb
+++ b/spec/syntax_checking_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry do
   before do
     @str_output = StringIO.new
diff --git a/spec/system_command_handler_spec.rb b/spec/system_command_handler_spec.rb
index 810fd606..45893e5d 100644
--- a/spec/system_command_handler_spec.rb
+++ b/spec/system_command_handler_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'stringio'
 
 RSpec.describe Pry::SystemCommandHandler do
diff --git a/spec/unrescued_exceptions_spec.rb b/spec/unrescued_exceptions_spec.rb
index 0874f0fa..592ac20f 100644
--- a/spec/unrescued_exceptions_spec.rb
+++ b/spec/unrescued_exceptions_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe "Pry.config.unrescued_exceptions" do
   before do
     @str_output = StringIO.new
diff --git a/spec/warning_spec.rb b/spec/warning_spec.rb
index 18bfa219..9c94ad5d 100644
--- a/spec/warning_spec.rb
+++ b/spec/warning_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Pry::Warning do
   describe "#warn" do
     it "prints message with file and line of the calling frame" do
diff --git a/spec/wrapped_module_spec.rb b/spec/wrapped_module_spec.rb
index f290fc76..a97affb9 100644
--- a/spec/wrapped_module_spec.rb
+++ b/spec/wrapped_module_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 describe Pry::WrappedModule do
   describe "#initialize" do
     it "should raise an exception when a non-module is passed" do