Compatibility with frozen string literals

92 files changed, 127 insertions, 28 deletions

diff --git a/lib/bundler/capistrano.rb b/lib/bundler/capistrano.rb
index 12499c7bf4..2a4954d964 100644
--- a/lib/bundler/capistrano.rb
+++ b/lib/bundler/capistrano.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # Capistrano task for Bundler.
 #
 # Just add "require 'bundler/capistrano'" in your Capistrano deploy.rb, and
diff --git a/lib/bundler/cli.rb b/lib/bundler/cli.rb
index 77eab33ddc..2445172321 100644
--- a/lib/bundler/cli.rb
+++ b/lib/bundler/cli.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler"
 require "bundler/vendored_thor"
 
diff --git a/lib/bundler/cli/binstubs.rb b/lib/bundler/cli/binstubs.rb
index cf9ce02c4d..8452ca3bfe 100644
--- a/lib/bundler/cli/binstubs.rb
+++ b/lib/bundler/cli/binstubs.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/cli/common"
 
 module Bundler
diff --git a/lib/bundler/cli/cache.rb b/lib/bundler/cli/cache.rb
index 8bc876baea..c8c63e926c 100644
--- a/lib/bundler/cli/cache.rb
+++ b/lib/bundler/cli/cache.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Cache
     attr_reader :options
diff --git a/lib/bundler/cli/check.rb b/lib/bundler/cli/check.rb
index fd09425e4a..f6a1022306 100644
--- a/lib/bundler/cli/check.rb
+++ b/lib/bundler/cli/check.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Check
     attr_reader :options
diff --git a/lib/bundler/cli/clean.rb b/lib/bundler/cli/clean.rb
index d70a5b9b89..895b6567fa 100644
--- a/lib/bundler/cli/clean.rb
+++ b/lib/bundler/cli/clean.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Clean
     attr_reader :options
diff --git a/lib/bundler/cli/common.rb b/lib/bundler/cli/common.rb
index b90544ba3a..491ea04a11 100644
--- a/lib/bundler/cli/common.rb
+++ b/lib/bundler/cli/common.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   module CLI::Common
     def self.without_groups_message
diff --git a/lib/bundler/cli/config.rb b/lib/bundler/cli/config.rb
index ce1be5eb4f..32724f687d 100644
--- a/lib/bundler/cli/config.rb
+++ b/lib/bundler/cli/config.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Config
     attr_reader :name, :options, :scope, :thor
@@ -11,7 +12,7 @@ module Bundler
       @scope = "global"
       return unless peek && peek.start_with?("--")
       @name = args.shift
-      @scope = $'
+      @scope = peek[2..-1]
     end
 
     def run
diff --git a/lib/bundler/cli/console.rb b/lib/bundler/cli/console.rb
index 6e4e1b6686..5e72cdbf0f 100644
--- a/lib/bundler/cli/console.rb
+++ b/lib/bundler/cli/console.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Console
     attr_reader :options, :group
diff --git a/lib/bundler/cli/exec.rb b/lib/bundler/cli/exec.rb
index 8b828edf87..4ccc4ba55a 100644
--- a/lib/bundler/cli/exec.rb
+++ b/lib/bundler/cli/exec.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/current_ruby"
 
 module Bundler
diff --git a/lib/bundler/cli/gem.rb b/lib/bundler/cli/gem.rb
index 343a458719..72a1880c52 100644
--- a/lib/bundler/cli/gem.rb
+++ b/lib/bundler/cli/gem.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "pathname"
 
 module Bundler
diff --git a/lib/bundler/cli/init.rb b/lib/bundler/cli/init.rb
index 1d201a90f5..4bbdee1f48 100644
--- a/lib/bundler/cli/init.rb
+++ b/lib/bundler/cli/init.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Init
     attr_reader :options
diff --git a/lib/bundler/cli/inject.rb b/lib/bundler/cli/inject.rb
index a17bce036f..e319feb201 100644
--- a/lib/bundler/cli/inject.rb
+++ b/lib/bundler/cli/inject.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Inject
     attr_reader :options, :name, :version, :gems
diff --git a/lib/bundler/cli/install.rb b/lib/bundler/cli/install.rb
index 559189b314..0e8599963b 100644
--- a/lib/bundler/cli/install.rb
+++ b/lib/bundler/cli/install.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Install
     attr_reader :options
diff --git a/lib/bundler/cli/lock.rb b/lib/bundler/cli/lock.rb
index 457826dfb5..e95e9ff636 100644
--- a/lib/bundler/cli/lock.rb
+++ b/lib/bundler/cli/lock.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Lock
     attr_reader :options
diff --git a/lib/bundler/cli/open.rb b/lib/bundler/cli/open.rb
index 0bf42038d9..d4dba703cd 100644
--- a/lib/bundler/cli/open.rb
+++ b/lib/bundler/cli/open.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/cli/common"
 require "shellwords"
 
diff --git a/lib/bundler/cli/outdated.rb b/lib/bundler/cli/outdated.rb
index 179635b803..3c85d0bdcd 100644
--- a/lib/bundler/cli/outdated.rb
+++ b/lib/bundler/cli/outdated.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/cli/common"
 
 module Bundler
diff --git a/lib/bundler/cli/package.rb b/lib/bundler/cli/package.rb
index de53cb6d8d..cf65e8a68c 100644
--- a/lib/bundler/cli/package.rb
+++ b/lib/bundler/cli/package.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Package
     attr_reader :options
diff --git a/lib/bundler/cli/platform.rb b/lib/bundler/cli/platform.rb
index 28641a4c8b..aec08789a9 100644
--- a/lib/bundler/cli/platform.rb
+++ b/lib/bundler/cli/platform.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Platform
     attr_reader :options
diff --git a/lib/bundler/cli/show.rb b/lib/bundler/cli/show.rb
index 50cf0a97d5..d67b086dd1 100644
--- a/lib/bundler/cli/show.rb
+++ b/lib/bundler/cli/show.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/cli/common"
 
 module Bundler
diff --git a/lib/bundler/cli/update.rb b/lib/bundler/cli/update.rb
index 0102bf0e1a..1a76a88c3d 100644
--- a/lib/bundler/cli/update.rb
+++ b/lib/bundler/cli/update.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Update
     attr_reader :options, :gems
diff --git a/lib/bundler/cli/viz.rb b/lib/bundler/cli/viz.rb
index 8fbc64d5fa..7ccd306d63 100644
--- a/lib/bundler/cli/viz.rb
+++ b/lib/bundler/cli/viz.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class CLI::Viz
     attr_reader :options, :gem_name
diff --git a/lib/bundler/constants.rb b/lib/bundler/constants.rb
index 704bcac84f..5b1c0a8cb1 100644
--- a/lib/bundler/constants.rb
+++ b/lib/bundler/constants.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   WINDOWS = RbConfig::CONFIG["host_os"] =~ /(msdos|mswin|djgpp|mingw)/
   FREEBSD = RbConfig::CONFIG["host_os"] =~ /bsd/
diff --git a/lib/bundler/current_ruby.rb b/lib/bundler/current_ruby.rb
index 671171dc37..a7fa2f3a89 100644
--- a/lib/bundler/current_ruby.rb
+++ b/lib/bundler/current_ruby.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   # Returns current version of Ruby
   #
diff --git a/lib/bundler/definition.rb b/lib/bundler/definition.rb
index 636d643a94..d98d8b15b6 100644
--- a/lib/bundler/definition.rb
+++ b/lib/bundler/definition.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/lockfile_parser"
 require "digest/sha1"
 require "set"
@@ -347,12 +348,13 @@ module Bundler
     end
 
     def ensure_equivalent_gemfile_and_lockfile(explicit_flag = false)
-      msg = "You are trying to install in deployment mode after changing\n" \
-            "your Gemfile. Run `bundle install` elsewhere and add the\n" \
-            "updated #{Bundler.default_lockfile.relative_path_from(SharedHelpers.pwd)} to version control."
+      msg = String.new
+      msg << "You are trying to install in deployment mode after changing\n" \
+             "your Gemfile. Run `bundle install` elsewhere and add the\n" \
+             "updated #{Bundler.default_lockfile.relative_path_from(SharedHelpers.pwd)} to version control."
 
       unless explicit_flag
-        msg += "\n\nIf this is a development machine, remove the #{Bundler.default_gemfile} " \
+        msg << "\n\nIf this is a development machine, remove the #{Bundler.default_gemfile} " \
                "freeze \nby running `bundle install --no-deployment`."
       end
 
diff --git a/lib/bundler/dep_proxy.rb b/lib/bundler/dep_proxy.rb
index 4efd99c9bb..998975bbaf 100644
--- a/lib/bundler/dep_proxy.rb
+++ b/lib/bundler/dep_proxy.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class DepProxy
     attr_reader :__platform, :dep
diff --git a/lib/bundler/dependency.rb b/lib/bundler/dependency.rb
index a62808d23c..1b1808b40a 100644
--- a/lib/bundler/dependency.rb
+++ b/lib/bundler/dependency.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rubygems/dependency"
 require "bundler/shared_helpers"
 require "bundler/rubygems_ext"
diff --git a/lib/bundler/deployment.rb b/lib/bundler/deployment.rb
index 163f61eabb..23968e7084 100644
--- a/lib/bundler/deployment.rb
+++ b/lib/bundler/deployment.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Deployment
     def self.define_task(context, task_method = :task, opts = {})
diff --git a/lib/bundler/deprecate.rb b/lib/bundler/deprecate.rb
index 02eb4b0918..1ab4de1a28 100644
--- a/lib/bundler/deprecate.rb
+++ b/lib/bundler/deprecate.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   if defined? ::Deprecate
     Deprecate = ::Deprecate
diff --git a/lib/bundler/dsl.rb b/lib/bundler/dsl.rb
index 8a3931e852..b3b6bfdcce 100644
--- a/lib/bundler/dsl.rb
+++ b/lib/bundler/dsl.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/dependency"
 require "bundler/ruby_dsl"
 
@@ -345,7 +346,8 @@ module Bundler
     def validate_keys(command, opts, valid_keys)
       invalid_keys = opts.keys - valid_keys
       if invalid_keys.any?
-        message = "You passed #{invalid_keys.map {|k| ":" + k }.join(", ")} "
+        message = String.new
+        message << "You passed #{invalid_keys.map {|k| ":" + k }.join(", ")} "
         message << if invalid_keys.size > 1
                      "as options for #{command}, but they are invalid."
                    else
@@ -450,7 +452,7 @@ module Bundler
         @to_s ||= begin
           trace_line, description = parse_line_number_from_description
 
-          m = "\n[!] "
+          m = String.new("\n[!] ")
           m << description
           m << ". Bundler cannot continue.\n"
 
diff --git a/lib/bundler/env.rb b/lib/bundler/env.rb
index 93d35900ae..baf6a10f31 100644
--- a/lib/bundler/env.rb
+++ b/lib/bundler/env.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/rubygems_integration"
 require "bundler/source/git/git_proxy"
 
diff --git a/lib/bundler/environment.rb b/lib/bundler/environment.rb
index 0e4ed37814..4e072602e6 100644
--- a/lib/bundler/environment.rb
+++ b/lib/bundler/environment.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Environment
     attr_reader :root
diff --git a/lib/bundler/errors.rb b/lib/bundler/errors.rb
index 9fc7b6df7b..eec8d00ef5 100644
--- a/lib/bundler/errors.rb
+++ b/lib/bundler/errors.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class BundlerError < StandardError
     def self.status_code(code)
diff --git a/lib/bundler/fetcher.rb b/lib/bundler/fetcher.rb
index 63f61070e3..348c29dcbe 100644
--- a/lib/bundler/fetcher.rb
+++ b/lib/bundler/fetcher.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/vendored_persistent"
 require "cgi"
 require "securerandom"
@@ -53,15 +54,17 @@ module Bundler
 
     # Exceptions classes that should bypass retry attempts. If your password didn't work the
     # first time, it's not going to the third time.
-    FAIL_ERRORS = [AuthenticationRequiredError, BadAuthenticationError, FallbackError].freeze
     NET_ERRORS = [:HTTPBadGateway, :HTTPBadRequest, :HTTPFailedDependency,
                   :HTTPForbidden, :HTTPInsufficientStorage, :HTTPMethodNotAllowed,
                   :HTTPMovedPermanently, :HTTPNoContent, :HTTPNotFound,
                   :HTTPNotImplemented, :HTTPPreconditionFailed, :HTTPRequestEntityTooLarge,
                   :HTTPRequestURITooLong, :HTTPUnauthorized, :HTTPUnprocessableEntity,
                   :HTTPUnsupportedMediaType, :HTTPVersionNotSupported].freeze
-    FAIL_ERRORS << Gem::Requirement::BadRequirementError if defined?(Gem::Requirement::BadRequirementError)
-    FAIL_ERRORS.push(*NET_ERRORS.map {|e| SharedHelpers.const_get_safely(e, Net) }.compact)
+    FAIL_ERRORS = begin
+      fail_errors = [AuthenticationRequiredError, BadAuthenticationError, FallbackError]
+      fail_errors << Gem::Requirement::BadRequirementError if defined?(Gem::Requirement::BadRequirementError)
+      fail_errors.push(*NET_ERRORS.map {|e| SharedHelpers.const_get_safely(e, Net) }.compact)
+    end.freeze
 
     class << self
       attr_accessor :disable_endpoint, :api_timeout, :redirect_limit, :max_retries
@@ -161,7 +164,7 @@ module Bundler
       @user_agent ||= begin
         ruby = Bundler::RubyVersion.system
 
-        agent = "bundler/#{Bundler::VERSION}"
+        agent = String.new("bundler/#{Bundler::VERSION}")
         agent << " rubygems/#{Gem::VERSION}"
         agent << " ruby/#{ruby.version}"
         agent << " (#{ruby.host})"
diff --git a/lib/bundler/fetcher/base.rb b/lib/bundler/fetcher/base.rb
index 1d1adc73db..f7210bd03d 100644
--- a/lib/bundler/fetcher/base.rb
+++ b/lib/bundler/fetcher/base.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Fetcher
     class Base
diff --git a/lib/bundler/fetcher/compact_index.rb b/lib/bundler/fetcher/compact_index.rb
index 0dd9b130be..f249ec1835 100644
--- a/lib/bundler/fetcher/compact_index.rb
+++ b/lib/bundler/fetcher/compact_index.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/fetcher/base"
 require "bundler/worker"
 
diff --git a/lib/bundler/fetcher/dependency.rb b/lib/bundler/fetcher/dependency.rb
index fdf91c1710..274b34eefd 100644
--- a/lib/bundler/fetcher/dependency.rb
+++ b/lib/bundler/fetcher/dependency.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/fetcher/base"
 require "cgi"
 
diff --git a/lib/bundler/fetcher/downloader.rb b/lib/bundler/fetcher/downloader.rb
index 9d8d783c8a..204e33387e 100644
--- a/lib/bundler/fetcher/downloader.rb
+++ b/lib/bundler/fetcher/downloader.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Fetcher
     class Downloader
diff --git a/lib/bundler/fetcher/index.rb b/lib/bundler/fetcher/index.rb
index f23811c8c5..d8e212989e 100644
--- a/lib/bundler/fetcher/index.rb
+++ b/lib/bundler/fetcher/index.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/fetcher/base"
 require "rubygems/remote_fetcher"
 
diff --git a/lib/bundler/friendly_errors.rb b/lib/bundler/friendly_errors.rb
index fd98bf55e1..b453e8e625 100644
--- a/lib/bundler/friendly_errors.rb
+++ b/lib/bundler/friendly_errors.rb
@@ -1,4 +1,5 @@
 # encoding: utf-8
+# frozen_string_literal: true
 require "cgi"
 require "bundler/vendored_thor"
 
@@ -68,7 +69,7 @@ module Bundler
         Error details
 
             #{e.class}: #{e.message}
-              #{e.backtrace.join("\n            ")}
+              #{e.backtrace.join("\n              ")}
 
         #{Bundler::Env.new.report(:print_gemfile => false, :print_gemspecs => false).gsub(/\n/, "\n      ").strip}
         --- TEMPLATE END ----------------------------------------------------------------
diff --git a/lib/bundler/gem_helper.rb b/lib/bundler/gem_helper.rb
index 30822148b4..41c574bfd2 100644
--- a/lib/bundler/gem_helper.rb
+++ b/lib/bundler/gem_helper.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/vendored_thor" unless defined?(Thor)
 require "bundler"
 
@@ -98,7 +99,7 @@ module Bundler
       gem_command = "gem push '#{path}'"
       if @gemspec.respond_to?(:metadata)
         allowed_push_host = @gemspec.metadata["allowed_push_host"]
-        gem_command << " --host #{allowed_push_host}" if allowed_push_host
+        gem_command += " --host #{allowed_push_host}" if allowed_push_host
       end
       sh(gem_command)
       Bundler.ui.confirm "Pushed #{name} #{version} to #{allowed_push_host ? allowed_push_host : "rubygems.org."}"
@@ -169,14 +170,15 @@ module Bundler
     end
 
     def sh_with_code(cmd, &block)
-      cmd << " 2>&1"
+      cmd += " 2>&1"
       outbuf = String.new
       Bundler.ui.debug(cmd)
       SharedHelpers.chdir(base) do
         outbuf = `#{cmd}`
-        block.call(outbuf) if $? == 0 && block
+        status = $?.exitstatus
+        block.call(outbuf) if status.zero? && block
+        [outbuf, status]
       end
-      [outbuf, $?]
     end
 
     def gem_push?
diff --git a/lib/bundler/gem_helpers.rb b/lib/bundler/gem_helpers.rb
index 6e43caef1a..5c824ffefc 100644
--- a/lib/bundler/gem_helpers.rb
+++ b/lib/bundler/gem_helpers.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 module Bundler
   module GemHelpers
-    GENERIC_CACHE = {}.freeze
+    GENERIC_CACHE = {} # rubocop:disable MutableConstant
     GENERICS = [
       [Gem::Platform.new("java"), Gem::Platform.new("java")],
       [Gem::Platform.new("mswin32"), Gem::Platform.new("mswin32")],
diff --git a/lib/bundler/gem_remote_fetcher.rb b/lib/bundler/gem_remote_fetcher.rb
index 8a823da963..481838a5e2 100644
--- a/lib/bundler/gem_remote_fetcher.rb
+++ b/lib/bundler/gem_remote_fetcher.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rubygems/remote_fetcher"
 
 module Bundler
diff --git a/lib/bundler/gem_tasks.rb b/lib/bundler/gem_tasks.rb
index 0ff383bf8b..230e7f28f2 100644
--- a/lib/bundler/gem_tasks.rb
+++ b/lib/bundler/gem_tasks.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rake/clean"
 CLOBBER.include "pkg"
 
diff --git a/lib/bundler/graph.rb b/lib/bundler/graph.rb
index 61c47380ac..c7e957ad7a 100644
--- a/lib/bundler/graph.rb
+++ b/lib/bundler/graph.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "set"
 module Bundler
   class Graph
diff --git a/lib/bundler/index.rb b/lib/bundler/index.rb
index 40ae97d5bd..f2defe1cff 100644
--- a/lib/bundler/index.rb
+++ b/lib/bundler/index.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "set"
 
 module Bundler
diff --git a/lib/bundler/injector.rb b/lib/bundler/injector.rb
index ef98fad888..c27e2499ca 100644
--- a/lib/bundler/injector.rb
+++ b/lib/bundler/injector.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Injector
     def self.inject(new_deps)
diff --git a/lib/bundler/inline.rb b/lib/bundler/inline.rb
index 9df19b02ad..da4afd01bb 100644
--- a/lib/bundler/inline.rb
+++ b/lib/bundler/inline.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # Allows for declaring a Gemfile inline in a ruby script, optionally installing
 # any gems that aren't already installed on the user's system.
 #
diff --git a/lib/bundler/installer.rb b/lib/bundler/installer.rb
index 4be5403607..3a54a02151 100644
--- a/lib/bundler/installer.rb
+++ b/lib/bundler/installer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "erb"
 require "rubygems/dependency_installer"
 require "bundler/worker"
diff --git a/lib/bundler/installer/gem_installer.rb b/lib/bundler/installer/gem_installer.rb
index f6f865b2ab..441c72108f 100644
--- a/lib/bundler/installer/gem_installer.rb
+++ b/lib/bundler/installer/gem_installer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class GemInstaller
     attr_reader :spec, :standalone, :worker, :force, :installer
diff --git a/lib/bundler/installer/parallel_installer.rb b/lib/bundler/installer/parallel_installer.rb
index 674c45af25..0a276aa9ea 100644
--- a/lib/bundler/installer/parallel_installer.rb
+++ b/lib/bundler/installer/parallel_installer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/worker"
 require "bundler/installer/gem_installer"
 
diff --git a/lib/bundler/installer/standalone.rb b/lib/bundler/installer/standalone.rb
index 40100b9540..69cfbfc455 100644
--- a/lib/bundler/installer/standalone.rb
+++ b/lib/bundler/installer/standalone.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Standalone
     def initialize(groups, definition)
diff --git a/lib/bundler/lazy_specification.rb b/lib/bundler/lazy_specification.rb
index b3d0d4e732..ccaa791cc8 100644
--- a/lib/bundler/lazy_specification.rb
+++ b/lib/bundler/lazy_specification.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "uri"
 require "rubygems/spec_fetcher"
 require "bundler/match_platform"
diff --git a/lib/bundler/match_platform.rb b/lib/bundler/match_platform.rb
index f4b9492c25..fed418b593 100644
--- a/lib/bundler/match_platform.rb
+++ b/lib/bundler/match_platform.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/gem_helpers"
 
 module Bundler
diff --git a/lib/bundler/mirror.rb b/lib/bundler/mirror.rb
index 45534be035..4978462bb3 100644
--- a/lib/bundler/mirror.rb
+++ b/lib/bundler/mirror.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Settings
     # Class used to build the mirror set and then find a mirror for a given URI
diff --git a/lib/bundler/path_preserver.rb b/lib/bundler/path_preserver.rb
index c37d7aa087..f5701cd67b 100644
--- a/lib/bundler/path_preserver.rb
+++ b/lib/bundler/path_preserver.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   module PathPreserver
     def self.preserve_path_in_environment(env_var, env)
diff --git a/lib/bundler/psyched_yaml.rb b/lib/bundler/psyched_yaml.rb
index 429cdb85f2..2c85cb0a53 100644
--- a/lib/bundler/psyched_yaml.rb
+++ b/lib/bundler/psyched_yaml.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # Psych could be a gem, so try to ask for it
 begin
   gem "psych"
diff --git a/lib/bundler/remote_specification.rb b/lib/bundler/remote_specification.rb
index 2ed4fadadc..29735fc6ab 100644
--- a/lib/bundler/remote_specification.rb
+++ b/lib/bundler/remote_specification.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "uri"
 require "rubygems/spec_fetcher"
 
diff --git a/lib/bundler/resolver.rb b/lib/bundler/resolver.rb
index e0a7f186ef..d22ab34e98 100644
--- a/lib/bundler/resolver.rb
+++ b/lib/bundler/resolver.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Resolver
     require "bundler/vendored_molinillo"
@@ -12,7 +13,7 @@ module Bundler
       end
 
       def message
-        conflicts.sort.reduce("") do |o, (name, conflict)|
+        conflicts.sort.reduce(String.new) do |o, (name, conflict)|
           o << %(Bundler could not find compatible versions for gem "#{name}":\n)
           if conflict.locked_requirement
             o << %(  In snapshot (#{Bundler.default_lockfile.basename}):\n)
@@ -341,7 +342,7 @@ module Bundler
         elsif requirement.source
           name = requirement.name
           versions = @source_requirements[name][name].map(&:version)
-          message  = "Could not find gem '#{requirement}' in #{requirement.source}.\n"
+          message  = String.new("Could not find gem '#{requirement}' in #{requirement.source}.\n")
           message << if versions.any?
                        "Source contains '#{name}' at: #{versions.join(", ")}"
                      else
diff --git a/lib/bundler/retry.rb b/lib/bundler/retry.rb
index 4b0fff4bd5..bf4d6ab7f7 100644
--- a/lib/bundler/retry.rb
+++ b/lib/bundler/retry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   # General purpose class for retrying code that may fail
   class Retry
diff --git a/lib/bundler/ruby_dsl.rb b/lib/bundler/ruby_dsl.rb
index 46587e98cf..47f2bcc337 100644
--- a/lib/bundler/ruby_dsl.rb
+++ b/lib/bundler/ruby_dsl.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   module RubyDsl
     def ruby(ruby_version, options = {})
diff --git a/lib/bundler/ruby_version.rb b/lib/bundler/ruby_version.rb
index 71ed828f71..b8f3b8a863 100644
--- a/lib/bundler/ruby_version.rb
+++ b/lib/bundler/ruby_version.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class RubyVersion
     attr_reader :version, :patchlevel, :engine, :engine_version
@@ -23,7 +24,7 @@ module Bundler
     end
 
     def to_s
-      output = "ruby #{version}"
+      output = String.new("ruby #{version}")
       output << "p#{patchlevel}" if patchlevel
       output << " (#{engine} #{engine_version})" unless engine == "ruby"
 
diff --git a/lib/bundler/rubygems_ext.rb b/lib/bundler/rubygems_ext.rb
index e1051a3851..22c22a2dd0 100644
--- a/lib/bundler/rubygems_ext.rb
+++ b/lib/bundler/rubygems_ext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "pathname"
 
 if defined?(Gem::QuickLoader)
@@ -78,7 +79,7 @@ module Gem
     end
 
     def to_gemfile(path = nil)
-      gemfile = "source 'https://rubygems.org'\n"
+      gemfile = String.new("source 'https://rubygems.org'\n")
       gemfile << dependencies_to_gemfile(nondevelopment_dependencies)
       unless development_dependencies.empty?
         gemfile << "\n"
diff --git a/lib/bundler/rubygems_gem_installer.rb b/lib/bundler/rubygems_gem_installer.rb
index 5d7be0cb7e..43637e1e60 100644
--- a/lib/bundler/rubygems_gem_installer.rb
+++ b/lib/bundler/rubygems_gem_installer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rubygems/installer"
 
 module Bundler
diff --git a/lib/bundler/rubygems_integration.rb b/lib/bundler/rubygems_integration.rb
index 5818f5b16a..c8ebe2cb9a 100644
--- a/lib/bundler/rubygems_integration.rb
+++ b/lib/bundler/rubygems_integration.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "monitor"
 require "rubygems"
 require "rubygems/config_file"
diff --git a/lib/bundler/runtime.rb b/lib/bundler/runtime.rb
index fff8a748af..6ef476b9dc 100644
--- a/lib/bundler/runtime.rb
+++ b/lib/bundler/runtime.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "digest/sha1"
 
 module Bundler
diff --git a/lib/bundler/settings.rb b/lib/bundler/settings.rb
index 8e0c2282ed..634d9dc14a 100644
--- a/lib/bundler/settings.rb
+++ b/lib/bundler/settings.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "uri"
 
 module Bundler
diff --git a/lib/bundler/setup.rb b/lib/bundler/setup.rb
index db13967bb1..9aae6478cd 100644
--- a/lib/bundler/setup.rb
+++ b/lib/bundler/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/shared_helpers"
 
 if Bundler::SharedHelpers.in_bundle?
diff --git a/lib/bundler/shared_helpers.rb b/lib/bundler/shared_helpers.rb
index 75aaf7c8f8..82b80eaa4a 100644
--- a/lib/bundler/shared_helpers.rb
+++ b/lib/bundler/shared_helpers.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "pathname"
 require "rubygems"
 
diff --git a/lib/bundler/similarity_detector.rb b/lib/bundler/similarity_detector.rb
index 624238552c..e9c1413ea3 100644
--- a/lib/bundler/similarity_detector.rb
+++ b/lib/bundler/similarity_detector.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class SimilarityDetector
     SimilarityScore = Struct.new(:string, :distance)
diff --git a/lib/bundler/source.rb b/lib/bundler/source.rb
index 0bcf9c3cfe..5f1eb130b7 100644
--- a/lib/bundler/source.rb
+++ b/lib/bundler/source.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Source
     autoload :Rubygems, "bundler/source/rubygems"
@@ -17,7 +18,7 @@ module Bundler
         locked_spec = Bundler.locked_gems.specs.find {|s| s.name == spec.name }
         locked_spec_version = locked_spec.version if locked_spec
         if locked_spec_version && spec.version != locked_spec_version
-          message << " (was #{locked_spec_version})"
+          message += " (was #{locked_spec_version})"
         end
       end
 
diff --git a/lib/bundler/source/git.rb b/lib/bundler/source/git.rb
index b11de1e4bc..90bbd13d34 100644
--- a/lib/bundler/source/git.rb
+++ b/lib/bundler/source/git.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "fileutils"
 require "uri"
 require "digest/sha1"
@@ -35,7 +36,7 @@ module Bundler
       end
 
       def to_lock
-        out = "GIT\n"
+        out = String.new("GIT\n")
         out << "  remote: #{@uri}\n"
         out << "  revision: #{revision}\n"
         %w(ref branch tag submodules).each do |opt|
diff --git a/lib/bundler/source/git/git_proxy.rb b/lib/bundler/source/git/git_proxy.rb
index a9f782e8d6..19e0db86fa 100644
--- a/lib/bundler/source/git/git_proxy.rb
+++ b/lib/bundler/source/git/git_proxy.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
 module Bundler
   class Source
     class Git < Path
       class GitNotInstalledError < GitError
         def initialize
-          msg =  "You need to install git to be able to use gems from git repositories. "
+          msg = String.new
+          msg << "You need to install git to be able to use gems from git repositories. "
           msg << "For help installing git, please refer to GitHub's tutorial at https://help.github.com/articles/set-up-git"
           super msg
         end
@@ -11,7 +13,8 @@ module Bundler
 
       class GitNotAllowedError < GitError
         def initialize(command)
-          msg =  "Bundler is trying to run a `git #{command}` at runtime. You probably need to run `bundle install`. However, "
+          msg = String.new
+          msg << "Bundler is trying to run a `git #{command}` at runtime. You probably need to run `bundle install`. However, "
           msg << "this error message could probably be more useful. Please submit a ticket at http://github.com/bundler/bundler/issues "
           msg << "with steps to reproduce as well as the following\n\nCALLER: #{caller.join("\n")}"
           super msg
@@ -20,7 +23,8 @@ module Bundler
 
       class GitCommandError < GitError
         def initialize(command, path = nil, extra_info = nil)
-          msg =  "Git error: command `git #{command}` in directory #{SharedHelpers.pwd} has failed."
+          msg = String.new
+          msg << "Git error: command `git #{command}` in directory #{SharedHelpers.pwd} has failed."
           msg << "\n#{extra_info}" if extra_info
           msg << "\nIf this error persists you could try removing the cache directory '#{path}'" if path && path.exist?
           super msg
diff --git a/lib/bundler/source/path.rb b/lib/bundler/source/path.rb
index 6f2fe2c1eb..6bfd2e88c7 100644
--- a/lib/bundler/source/path.rb
+++ b/lib/bundler/source/path.rb
@@ -158,7 +158,7 @@ module Bundler
             end
           end
         else
-          message = "The path `#{expanded_path}` "
+          message = String.new("The path `#{expanded_path}` ")
           message << if File.exist?(expanded_path)
                        "is not a directory."
                      else
diff --git a/lib/bundler/source/path/installer.rb b/lib/bundler/source/path/installer.rb
index 74542dd913..0aa27bd564 100644
--- a/lib/bundler/source/path/installer.rb
+++ b/lib/bundler/source/path/installer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Source
     class Path
diff --git a/lib/bundler/source/rubygems.rb b/lib/bundler/source/rubygems.rb
index 1315677a52..cebb68a700 100644
--- a/lib/bundler/source/rubygems.rb
+++ b/lib/bundler/source/rubygems.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "uri"
 require "rubygems/user_interaction"
 require "rubygems/spec_fetcher"
@@ -118,7 +119,7 @@ module Bundler
 
         unless Bundler.settings[:no_install]
           message = "Installing #{version_message(spec)}"
-          message << " with native extensions" if spec.extensions.any?
+          message += " with native extensions" if spec.extensions.any?
           Bundler.ui.confirm message
 
           path = cached_gem(spec)
diff --git a/lib/bundler/source/rubygems/remote.rb b/lib/bundler/source/rubygems/remote.rb
index 4cd8ea23b8..32265fb600 100644
--- a/lib/bundler/source/rubygems/remote.rb
+++ b/lib/bundler/source/rubygems/remote.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class Source
     class Rubygems
diff --git a/lib/bundler/source_list.rb b/lib/bundler/source_list.rb
index c0336bfdd6..dc62c8926a 100644
--- a/lib/bundler/source_list.rb
+++ b/lib/bundler/source_list.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   class SourceList
     attr_reader :path_sources,
diff --git a/lib/bundler/spec_set.rb b/lib/bundler/spec_set.rb
index 855a6e3317..5ec546e8e3 100644
--- a/lib/bundler/spec_set.rb
+++ b/lib/bundler/spec_set.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "tsort"
 require "forwardable"
 
diff --git a/lib/bundler/ssl_certs/certificate_manager.rb b/lib/bundler/ssl_certs/certificate_manager.rb
index 558bd9ef50..76639a0cf1 100644
--- a/lib/bundler/ssl_certs/certificate_manager.rb
+++ b/lib/bundler/ssl_certs/certificate_manager.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "fileutils"
 require "net/https"
 require "openssl"
diff --git a/lib/bundler/stub_specification.rb b/lib/bundler/stub_specification.rb
index ca5cbe6d9d..f4ee7d0644 100644
--- a/lib/bundler/stub_specification.rb
+++ b/lib/bundler/stub_specification.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/remote_specification"
 
 module Bundler
diff --git a/lib/bundler/templates/Executable b/lib/bundler/templates/Executable
index cc9e06cfec..b72c267dd1 100755
--- a/lib/bundler/templates/Executable
+++ b/lib/bundler/templates/Executable
@@ -1,4 +1,5 @@
 #!/usr/bin/env <%= Bundler.settings[:shebang] || RbConfig::CONFIG['ruby_install_name'] %>
+# frozen_string_literal: true
 #
 # This file was generated by Bundler.
 #
diff --git a/lib/bundler/templates/Gemfile b/lib/bundler/templates/Gemfile
index 8d5b66ea29..3f953369c3 100644
--- a/lib/bundler/templates/Gemfile
+++ b/lib/bundler/templates/Gemfile
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # A sample Gemfile
 source "https://rubygems.org"
 
diff --git a/lib/bundler/ui.rb b/lib/bundler/ui.rb
index 7400f80ab1..794c000dc4 100644
--- a/lib/bundler/ui.rb
+++ b/lib/bundler/ui.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   module UI
     autoload :RGProxy, "bundler/ui/rg_proxy"
diff --git a/lib/bundler/ui/rg_proxy.rb b/lib/bundler/ui/rg_proxy.rb
index 1c9c2deaba..95a1ecdf0c 100644
--- a/lib/bundler/ui/rg_proxy.rb
+++ b/lib/bundler/ui/rg_proxy.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/ui"
 require "rubygems/user_interaction"
 
diff --git a/lib/bundler/ui/shell.rb b/lib/bundler/ui/shell.rb
index 51919a8a5f..425ffae332 100644
--- a/lib/bundler/ui/shell.rb
+++ b/lib/bundler/ui/shell.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "bundler/vendored_thor"
 
 module Bundler
diff --git a/lib/bundler/ui/silent.rb b/lib/bundler/ui/silent.rb
index 3eb3199b5c..9f387d9e9f 100644
--- a/lib/bundler/ui/silent.rb
+++ b/lib/bundler/ui/silent.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler
   module UI
     class Silent
diff --git a/lib/bundler/vendored_molinillo.rb b/lib/bundler/vendored_molinillo.rb
index 795d63a3d3..7b231263cb 100644
--- a/lib/bundler/vendored_molinillo.rb
+++ b/lib/bundler/vendored_molinillo.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 module Bundler; end
 require "bundler/vendor/molinillo/lib/molinillo"
diff --git a/lib/bundler/vendored_persistent.rb b/lib/bundler/vendored_persistent.rb
index ef404f35d5..d5ae513c59 100644
--- a/lib/bundler/vendored_persistent.rb
+++ b/lib/bundler/vendored_persistent.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # We forcibly require OpenSSL, because net/http/persistent will only autoload
 # it. On some Rubies, autoload fails but explicit require succeeds.
 begin
diff --git a/lib/bundler/vendored_thor.rb b/lib/bundler/vendored_thor.rb
index 114483db02..0d0b45bfba 100644
--- a/lib/bundler/vendored_thor.rb
+++ b/lib/bundler/vendored_thor.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Bundler; end
 require "bundler/vendor/thor/lib/thor"
 require "bundler/vendor/thor/lib/thor/actions"
diff --git a/lib/bundler/vlad.rb b/lib/bundler/vlad.rb
index 5e20ae6dac..d017ca475a 100644
--- a/lib/bundler/vlad.rb
+++ b/lib/bundler/vlad.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # Vlad task for Bundler.
 #
 # Just add "require 'bundler/vlad'" in your Vlad deploy.rb, and
diff --git a/lib/bundler/worker.rb b/lib/bundler/worker.rb
index e74823e202..3ef5addcee 100644
--- a/lib/bundler/worker.rb
+++ b/lib/bundler/worker.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "thread"
 
 module Bundler