Merge RubyGems-3.3.20 and Bundler-2.3.20

66 files changed, 277 insertions, 268 deletions

diff --git a/lib/rubygems/available_set.rb b/lib/rubygems/available_set.rb
index 499483d9e9..58b601f6b0 100644
--- a/lib/rubygems/available_set.rb
+++ b/lib/rubygems/available_set.rb
@@ -26,7 +26,7 @@ class Gem::AvailableSet
       s = o.set
     when Array
       s = o.map do |sp,so|
-        if !sp.kind_of?(Gem::Specification) or !so.kind_of?(Gem::Source)
+        if !sp.kind_of?(Gem::Specification) || !so.kind_of?(Gem::Source)
           raise TypeError, "Array must be in [[spec, source], ...] form"
         end
 
@@ -149,8 +149,8 @@ class Gem::AvailableSet
     @set.reject! do |t|
       # already locally installed
       Gem::Specification.any? do |installed_spec|
-        dep.name == installed_spec.name and
-          dep.requirement.satisfied_by? installed_spec.version
+        dep.name == installed_spec.name &&
+          dep.requirement.satisfied_by?(installed_spec.version)
       end
     end
 
diff --git a/lib/rubygems/basic_specification.rb b/lib/rubygems/basic_specification.rb
index 526a5069c2..dcc64e6409 100644
--- a/lib/rubygems/basic_specification.rb
+++ b/lib/rubygems/basic_specification.rb
@@ -77,7 +77,7 @@ class Gem::BasicSpecification
 
       if Gem::Platform::RUBY == platform || Gem::Platform.local === platform
         warn "Ignoring #{full_name} because its extensions are not built. " +
-          "Try: gem pristine #{name} --version #{version}"
+             "Try: gem pristine #{name} --version #{version}"
       end
 
       return false
@@ -131,7 +131,7 @@ class Gem::BasicSpecification
   # default Ruby platform.
 
   def full_name
-    if platform == Gem::Platform::RUBY or platform.nil?
+    if platform == Gem::Platform::RUBY || platform.nil?
       "#{name}-#{version}".dup.tap(&Gem::UNTAINT)
     else
       "#{name}-#{version}-#{platform}".dup.tap(&Gem::UNTAINT)
diff --git a/lib/rubygems/command.rb b/lib/rubygems/command.rb
index 9fc3360fa1..badc21023a 100644
--- a/lib/rubygems/command.rb
+++ b/lib/rubygems/command.rb
@@ -159,11 +159,11 @@ class Gem::Command
     gem = "'#{gem_name}' (#{version})"
     msg = String.new "Could not find a valid gem #{gem}"
 
-    if errors and !errors.empty?
+    if errors && !errors.empty?
       msg << ", here is why:\n"
       errors.each {|x| msg << "          #{x.wordy}\n" }
     else
-      if required_by and gem != required_by
+      if required_by && gem != required_by
         msg << " (required by #{required_by}) in any repository"
       else
         msg << " in any repository"
@@ -186,7 +186,7 @@ class Gem::Command
   def get_all_gem_names
     args = options[:args]
 
-    if args.nil? or args.empty?
+    if args.nil? || args.empty?
       raise Gem::CommandLineError,
             "Please specify at least one gem name (e.g. gem build GEMNAME)"
     end
@@ -216,7 +216,7 @@ class Gem::Command
   def get_one_gem_name
     args = options[:args]
 
-    if args.nil? or args.empty?
+    if args.nil? || args.empty?
       raise Gem::CommandLineError,
             "Please specify a gem name on the command line (e.g. gem build GEMNAME)"
     end
@@ -554,7 +554,7 @@ class Gem::Command
   end
 
   def configure_options(header, option_list)
-    return if option_list.nil? or option_list.empty?
+    return if option_list.nil? || option_list.empty?
 
     header = header.to_s.empty? ? "" : "#{header} "
     @parser.separator "  #{header}Options:"
@@ -586,7 +586,7 @@ class Gem::Command
   add_common_option("-V", "--[no-]verbose",
                     "Set the verbose level of output") do |value, options|
     # Set us to "really verbose" so the progress meter works
-    if Gem.configuration.verbose and value
+    if Gem.configuration.verbose && value
       Gem.configuration.verbose = 1
     else
       Gem.configuration.verbose = value
diff --git a/lib/rubygems/commands/cert_command.rb b/lib/rubygems/commands/cert_command.rb
index 56bf5ce689..17b1d11b19 100644
--- a/lib/rubygems/commands/cert_command.rb
+++ b/lib/rubygems/commands/cert_command.rb
@@ -152,7 +152,7 @@ class Gem::Commands::CertCommand < Gem::Command
 
   def build_cert(email, key) # :nodoc:
     expiration_length_days = options[:expiration_length_days] ||
-      Gem.configuration.cert_expiration_length_days
+                             Gem.configuration.cert_expiration_length_days
 
     cert = Gem::Security.create_cert_email(
       email,
diff --git a/lib/rubygems/commands/cleanup_command.rb b/lib/rubygems/commands/cleanup_command.rb
index 7f143999eb..1ae84924c1 100644
--- a/lib/rubygems/commands/cleanup_command.rb
+++ b/lib/rubygems/commands/cleanup_command.rb
@@ -149,7 +149,7 @@ If no gems are named all gems in GEM_HOME are cleaned.
     @primary_gems = {}
 
     Gem::Specification.each do |spec|
-      if @primary_gems[spec.name].nil? or
+      if @primary_gems[spec.name].nil? ||
          @primary_gems[spec.name].version < spec.version
         @primary_gems[spec.name] = spec
       end
diff --git a/lib/rubygems/commands/contents_command.rb b/lib/rubygems/commands/contents_command.rb
index 3dd0b16265..c5fdfca31e 100644
--- a/lib/rubygems/commands/contents_command.rb
+++ b/lib/rubygems/commands/contents_command.rb
@@ -77,7 +77,7 @@ prefix or only the files that are requireable.
           gem_contents name
         end
 
-      terminate_interaction 1 unless found or names.length > 1
+      terminate_interaction 1 unless found || names.length > 1
     end
   end
 
diff --git a/lib/rubygems/commands/dependency_command.rb b/lib/rubygems/commands/dependency_command.rb
index c9ddc9af0a..3f69a95e83 100644
--- a/lib/rubygems/commands/dependency_command.rb
+++ b/lib/rubygems/commands/dependency_command.rb
@@ -77,7 +77,7 @@ use with other commands.
         name_matches = name_pattern ? name_pattern =~ spec.name : true
         version_matches = requirement.satisfied_by?(spec.version)
 
-        name_matches and version_matches
+        name_matches && version_matches
       }.map(&:to_spec)
     end
 
@@ -133,7 +133,7 @@ use with other commands.
   end
 
   def ensure_local_only_reverse_dependencies # :nodoc:
-    if options[:reverse_dependencies] and remote? and not local?
+    if options[:reverse_dependencies] && remote? && !local?
       alert_error "Only reverse dependencies for local gems are supported."
       terminate_interaction 1
     end
@@ -182,7 +182,7 @@ use with other commands.
       sp.dependencies.each do |dep|
         dep = Gem::Dependency.new(*dep) unless Gem::Dependency === dep
 
-        if spec.name == dep.name and
+        if spec.name == dep.name &&
            dep.requirement.satisfied_by?(spec.version)
           result << [sp.full_name, dep]
         end
@@ -197,7 +197,7 @@ use with other commands.
   def name_pattern(args)
     return if args.empty?
 
-    if args.length == 1 and args.first =~ /\A(.*)(i)?\z/m
+    if args.length == 1 && args.first =~ /\A(.*)(i)?\z/m
       flags = $2 ? Regexp::IGNORECASE : nil
       Regexp.new $1, flags
     else
diff --git a/lib/rubygems/commands/fetch_command.rb b/lib/rubygems/commands/fetch_command.rb
index 582563ba81..3a8c435d0e 100644
--- a/lib/rubygems/commands/fetch_command.rb
+++ b/lib/rubygems/commands/fetch_command.rb
@@ -52,8 +52,8 @@ then repackaging it.
   end
 
   def check_version # :nodoc:
-    if options[:version] != Gem::Requirement.default and
-         get_all_gem_names.size > 1
+    if options[:version] != Gem::Requirement.default &&
+       get_all_gem_names.size > 1
       alert_error "Can't use --version with multiple gems. You can specify multiple gems with" \
                   " version requirements using `gem fetch 'my_gem:1.0.0' 'my_other_gem:~>2.0.0'`"
       terminate_interaction 1
diff --git a/lib/rubygems/commands/generate_index_command.rb b/lib/rubygems/commands/generate_index_command.rb
index 8bb24c9ce3..bc71e60ff0 100644
--- a/lib/rubygems/commands/generate_index_command.rb
+++ b/lib/rubygems/commands/generate_index_command.rb
@@ -68,8 +68,8 @@ Marshal::MINOR_VERSION constants.  It is used to ensure compatibility.
     # This is always true because it's the only way now.
     options[:build_modern] = true
 
-    if not File.exist?(options[:directory]) or
-       not File.directory?(options[:directory])
+    if !File.exist?(options[:directory]) ||
+       !File.directory?(options[:directory])
       alert_error "unknown directory name #{options[:directory]}."
       terminate_interaction 1
     else
diff --git a/lib/rubygems/commands/install_command.rb b/lib/rubygems/commands/install_command.rb
index 690f90c2e4..724b4fe51d 100644
--- a/lib/rubygems/commands/install_command.rb
+++ b/lib/rubygems/commands/install_command.rb
@@ -46,8 +46,8 @@ class Gem::Commands::InstallCommand < Gem::Command
 
   def defaults_str # :nodoc:
     "--both --version '#{Gem::Requirement.default}' --no-force\n" +
-    "--install-dir #{Gem.dir} --lock\n" +
-    install_update_defaults_str
+      "--install-dir #{Gem.dir} --lock\n" +
+      install_update_defaults_str
   end
 
   def description # :nodoc:
@@ -134,15 +134,15 @@ You can use `i` command instead of `install`.
   end
 
   def check_install_dir # :nodoc:
-    if options[:install_dir] and options[:user_install]
+    if options[:install_dir] && options[:user_install]
       alert_error "Use --install-dir or --user-install but not both"
       terminate_interaction 1
     end
   end
 
   def check_version # :nodoc:
-    if options[:version] != Gem::Requirement.default and
-         get_all_gem_names.size > 1
+    if options[:version] != Gem::Requirement.default &&
+       get_all_gem_names.size > 1
       alert_error "Can't use --version with multiple gems. You can specify multiple gems with" \
                   " version requirements using `gem install 'my_gem:1.0.0' 'my_other_gem:~>2.0.0'`"
       terminate_interaction 1
@@ -191,8 +191,8 @@ You can use `i` command instead of `install`.
   end
 
   def install_gem(name, version) # :nodoc:
-    return if options[:conservative] and
-      not Gem::Dependency.new(name, version).matching_specs.empty?
+    return if options[:conservative] &&
+              !Gem::Dependency.new(name, version).matching_specs.empty?
 
     req = Gem::Requirement.create(version)
 
diff --git a/lib/rubygems/commands/pristine_command.rb b/lib/rubygems/commands/pristine_command.rb
index d4dadf0736..72db53ef37 100644
--- a/lib/rubygems/commands/pristine_command.rb
+++ b/lib/rubygems/commands/pristine_command.rb
@@ -102,10 +102,10 @@ extensions will be restored.
 
     # `--extensions` must be explicitly given to pristine only gems
     # with extensions.
-    elsif options[:extensions_set] and
-                  options[:extensions] and options[:args].empty?
+    elsif options[:extensions_set] &&
+          options[:extensions] && options[:args].empty?
       Gem::Specification.select do |spec|
-        spec.extensions and not spec.extensions.empty?
+        spec.extensions && !spec.extensions.empty?
       end
     else
       get_all_gem_names.sort.map do |gem_name|
@@ -135,14 +135,14 @@ extensions will be restored.
         end
       end
 
-      unless spec.extensions.empty? or options[:extensions] or options[:only_executables] or options[:only_plugins]
+      unless spec.extensions.empty? || options[:extensions] || options[:only_executables] || options[:only_plugins]
         say "Skipped #{spec.full_name}, it needs to compile an extension"
         next
       end
 
       gem = spec.cache_file
 
-      unless File.exist? gem or options[:only_executables] or options[:only_plugins]
+      unless File.exist?(gem) || options[:only_executables] || options[:only_plugins]
         require_relative "../remote_fetcher"
 
         say "Cached gem for #{spec.full_name} not found, attempting to fetch..."
diff --git a/lib/rubygems/commands/setup_command.rb b/lib/rubygems/commands/setup_command.rb
index 1ed889a713..c782c3618c 100644
--- a/lib/rubygems/commands/setup_command.rb
+++ b/lib/rubygems/commands/setup_command.rb
@@ -329,9 +329,9 @@ By default, this RubyGems will install gem as:
       # ignore
     end
 
-    if File.writable? gem_doc_dir and
-       (not File.exist? rubygems_doc_dir or
-        File.writable? rubygems_doc_dir)
+    if File.writable?(gem_doc_dir) &&
+       (!File.exist?(rubygems_doc_dir) ||
+        File.writable?(rubygems_doc_dir))
       say "Removing old RubyGems RDoc and ri" if @verbose
       Dir[File.join(Gem.dir, "doc", "rubygems-[0-9]*")].each do |dir|
         rm_rf dir
@@ -559,7 +559,7 @@ abort "#{deprecation_message}"
 
         history_string = ""
 
-        until versions.length == 0 or
+        until versions.length == 0 ||
               versions.shift <= options[:previous_version] do
           history_string += version_lines.shift + text.shift
         end
diff --git a/lib/rubygems/commands/sources_command.rb b/lib/rubygems/commands/sources_command.rb
index a5f2d022c6..5a8f5af9c3 100644
--- a/lib/rubygems/commands/sources_command.rb
+++ b/lib/rubygems/commands/sources_command.rb
@@ -82,7 +82,7 @@ Do you want to add this source?
   def check_rubygems_https(source_uri) # :nodoc:
     uri = URI source_uri
 
-    if uri.scheme and uri.scheme.downcase == "http" and
+    if uri.scheme && uri.scheme.downcase == "http" &&
        uri.host.downcase == "rubygems.org"
       question = <<-QUESTION.chomp
 https://rubygems.org is recommended for security over #{uri}
@@ -215,9 +215,9 @@ To remove a source use the --remove argument:
   def remove_cache_file(desc, path) # :nodoc:
     FileUtils.rm_rf path
 
-    if not File.exist?(path)
+    if !File.exist?(path)
       say "*** Removed #{desc} source cache ***"
-    elsif not File.writable?(path)
+    elsif !File.writable?(path)
       say "*** Unable to remove #{desc} source cache (write protected) ***"
     else
       say "*** Unable to remove #{desc} source cache ***"
diff --git a/lib/rubygems/commands/specification_command.rb b/lib/rubygems/commands/specification_command.rb
index 6457a755ae..12004a6d56 100644
--- a/lib/rubygems/commands/specification_command.rb
+++ b/lib/rubygems/commands/specification_command.rb
@@ -88,7 +88,7 @@ Specific fields in the specification can be extracted in YAML format:
       raise Gem::CommandLineError, "Unsupported version type: '#{v}'"
     end
 
-    if !req.none? and options[:all]
+    if !req.none? && options[:all]
       alert_error "Specify --all or -v, not both"
       terminate_interaction 1
     end
@@ -102,7 +102,7 @@ Specific fields in the specification can be extracted in YAML format:
     field = get_one_optional_argument
 
     raise Gem::CommandLineError, "--ruby and FIELD are mutually exclusive" if
-      field and options[:format] == :ruby
+      field && options[:format] == :ruby
 
     if local?
       if File.exist? gem
diff --git a/lib/rubygems/commands/uninstall_command.rb b/lib/rubygems/commands/uninstall_command.rb
index d03a96bf87..3c520826e5 100644
--- a/lib/rubygems/commands/uninstall_command.rb
+++ b/lib/rubygems/commands/uninstall_command.rb
@@ -96,7 +96,7 @@ class Gem::Commands::UninstallCommand < Gem::Command
 
   def defaults_str # :nodoc:
     "--version '#{Gem::Requirement.default}' --no-force " +
-    "--user-install"
+      "--user-install"
   end
 
   def description # :nodoc:
@@ -114,8 +114,8 @@ that is a dependency of an existing gem.  You can use the
   end
 
   def check_version # :nodoc:
-    if options[:version] != Gem::Requirement.default and
-         get_all_gem_names.size > 1
+    if options[:version] != Gem::Requirement.default &&
+       get_all_gem_names.size > 1
       alert_error "Can't use --version with multiple gems. You can specify multiple gems with" \
                   " version requirements using `gem uninstall 'my_gem:1.0.0' 'my_other_gem:~>2.0.0'`"
       terminate_interaction 1
@@ -125,7 +125,7 @@ that is a dependency of an existing gem.  You can use the
   def execute
     check_version
 
-    if options[:all] and not options[:args].empty?
+    if options[:all] && !options[:args].empty?
       uninstall_specific
     elsif options[:all]
       uninstall_all
diff --git a/lib/rubygems/commands/update_command.rb b/lib/rubygems/commands/update_command.rb
index a079642669..7c24fedcde 100644
--- a/lib/rubygems/commands/update_command.rb
+++ b/lib/rubygems/commands/update_command.rb
@@ -56,7 +56,7 @@ class Gem::Commands::UpdateCommand < Gem::Command
 
   def defaults_str # :nodoc:
     "--no-force --install-dir #{Gem.dir}\n" +
-    install_update_defaults_str
+      install_update_defaults_str
   end
 
   def description # :nodoc:
@@ -155,7 +155,7 @@ command to remove old versions.
     Gem::Specification.dirs = Gem.user_dir if options[:user_install]
 
     Gem::Specification.each do |spec|
-      if hig[spec.name].nil? or hig[spec.name].version < spec.version
+      if hig[spec.name].nil? || hig[spec.name].version < spec.version
         hig[spec.name] = spec
       end
     end
@@ -292,8 +292,8 @@ command to remove old versions.
     args << "--no-document" unless options[:document].include?("rdoc") || options[:document].include?("ri")
     args << "--no-format-executable" if options[:no_format_executable]
     args << "--previous-version" << Gem::VERSION if
-      options[:system] == true or
-        Gem::Version.new(options[:system]) >= Gem::Version.new(2)
+      options[:system] == true ||
+      Gem::Version.new(options[:system]) >= Gem::Version.new(2)
     args
   end
 
@@ -301,7 +301,7 @@ command to remove old versions.
     result = []
 
     highest_installed_gems.each do |l_name, l_spec|
-      next if not gem_names.empty? and
+      next if !gem_names.empty? &&
               gem_names.none? {|name| name == l_spec.name }
 
       highest_remote_tup = highest_remote_name_tuple l_spec
diff --git a/lib/rubygems/commands/which_command.rb b/lib/rubygems/commands/which_command.rb
index 78493e9380..5b9a79b734 100644
--- a/lib/rubygems/commands/which_command.rb
+++ b/lib/rubygems/commands/which_command.rb
@@ -71,7 +71,7 @@ requiring to see why it does not behave as you expect.
     dirs.each do |dir|
       Gem.suffixes.each do |ext|
         full_path = File.join dir, "#{package_name}#{ext}"
-        if File.exist? full_path and not File.directory? full_path
+        if File.exist?(full_path) && !File.directory?(full_path)
           result << full_path
           return result unless options[:show_all]
         end
diff --git a/lib/rubygems/config_file.rb b/lib/rubygems/config_file.rb
index d711a51bd0..c53e209ae8 100644
--- a/lib/rubygems/config_file.rb
+++ b/lib/rubygems/config_file.rb
@@ -39,7 +39,7 @@ require "rbconfig"
 class Gem::ConfigFile
   include Gem::UserInteraction
 
-  DEFAULT_BACKTRACE = false
+  DEFAULT_BACKTRACE = true
   DEFAULT_BULK_THRESHOLD = 1000
   DEFAULT_VERBOSITY = true
   DEFAULT_UPDATE_SOURCES = true
@@ -368,7 +368,7 @@ if you believe they were disclosed to a third party.
 
   # True if the backtrace option has been specified, or debug is on.
   def backtrace
-    @backtrace or $DEBUG
+    @backtrace || $DEBUG
   end
 
   # The name of the configuration file.
@@ -477,11 +477,11 @@ if you believe they were disclosed to a third party.
   end
 
   def ==(other) # :nodoc:
-    self.class === other and
-      @backtrace == other.backtrace and
-      @bulk_threshold == other.bulk_threshold and
-      @verbose == other.verbose and
-      @update_sources == other.update_sources and
+    self.class === other &&
+      @backtrace == other.backtrace &&
+      @bulk_threshold == other.bulk_threshold &&
+      @verbose == other.verbose &&
+      @update_sources == other.update_sources &&
       @hash == other.hash
   end
 
diff --git a/lib/rubygems/core_ext/kernel_warn.rb b/lib/rubygems/core_ext/kernel_warn.rb
index 7df6c48b8f..8f43e00456 100644
--- a/lib/rubygems/core_ext/kernel_warn.rb
+++ b/lib/rubygems/core_ext/kernel_warn.rb
@@ -39,7 +39,7 @@ if RUBY_VERSION >= "2.5" && !Gem::KERNEL_WARN_IGNORES_INTERNAL_ENTRIES
           start += 1
 
           if path = loc.path
-            unless path.start_with?(rubygems_path) or path.start_with?("<internal:")
+            unless path.start_with?(rubygems_path) || path.start_with?("<internal:")
               # Non-rubygems frames
               uplevel -= 1
             end
diff --git a/lib/rubygems/defaults.rb b/lib/rubygems/defaults.rb
index d27f286265..d5caea7665 100644
--- a/lib/rubygems/defaults.rb
+++ b/lib/rubygems/defaults.rb
@@ -161,7 +161,7 @@ module Gem
     path = []
     path << user_dir if user_home && File.exist?(user_home)
     path << default_dir
-    path << vendor_dir if vendor_dir and File.directory? vendor_dir
+    path << vendor_dir if vendor_dir && File.directory?(vendor_dir)
     path
   end
 
diff --git a/lib/rubygems/dependency.rb b/lib/rubygems/dependency.rb
index c561db1af2..85f8609677 100644
--- a/lib/rubygems/dependency.rb
+++ b/lib/rubygems/dependency.rb
@@ -115,7 +115,7 @@ class Gem::Dependency
   # What does this dependency require?
 
   def requirement
-    return @requirement if defined?(@requirement) and @requirement
+    return @requirement if defined?(@requirement) && @requirement
 
     # @version_requirements and @version_requirement are legacy ivar
     # names, and supported here because older gems need to keep
@@ -230,10 +230,10 @@ class Gem::Dependency
 
     version = Gem::Version.new version
 
-    return true if requirement.none? and not version.prerelease?
-    return false if version.prerelease? and
-                    not allow_prerelease and
-                    not prerelease?
+    return true if requirement.none? && !version.prerelease?
+    return false if version.prerelease? &&
+                    !allow_prerelease &&
+                    !prerelease?
 
     requirement.satisfied_by? version
   end
diff --git a/lib/rubygems/dependency_installer.rb b/lib/rubygems/dependency_installer.rb
index acdad6b98f..aa7b66d36b 100644
--- a/lib/rubygems/dependency_installer.rb
+++ b/lib/rubygems/dependency_installer.rb
@@ -109,7 +109,7 @@ class Gem::DependencyInstaller
   # gems should be considered.
 
   def consider_local?
-    @domain == :both or @domain == :local
+    @domain == :both || @domain == :local
   end
 
   ##
@@ -117,7 +117,7 @@ class Gem::DependencyInstaller
   # gems should be considered.
 
   def consider_remote?
-    @domain == :both or @domain == :remote
+    @domain == :both || @domain == :remote
   end
 
   ##
@@ -197,7 +197,7 @@ class Gem::DependencyInstaller
 
   def in_background(what) # :nodoc:
     fork_happened = false
-    if @build_docs_in_background and Process.respond_to?(:fork)
+    if @build_docs_in_background && Process.respond_to?(:fork)
       begin
         Process.fork do
           yield
@@ -268,7 +268,7 @@ class Gem::DependencyInstaller
   end
 
   def install_development_deps # :nodoc:
-    if @development and @dev_shallow
+    if @development && @dev_shallow
       :shallow
     elsif @development
       :all
@@ -289,7 +289,7 @@ class Gem::DependencyInstaller
     installer_set.force = @force
 
     if consider_local?
-      if dep_or_name =~ /\.gem$/ and File.file? dep_or_name
+      if dep_or_name =~ /\.gem$/ && File.file?(dep_or_name)
         src = Gem::Source::SpecificFile.new dep_or_name
         installer_set.add_local dep_or_name, src.spec, src
         version = src.spec.version if version == Gem::Requirement.default
diff --git a/lib/rubygems/dependency_list.rb b/lib/rubygems/dependency_list.rb
index 3cecb1e536..eaf6702177 100644
--- a/lib/rubygems/dependency_list.rb
+++ b/lib/rubygems/dependency_list.rb
@@ -119,11 +119,11 @@ class Gem::DependencyList
     each do |spec|
       spec.runtime_dependencies.each do |dep|
         inst = Gem::Specification.any? do |installed_spec|
-          dep.name == installed_spec.name and
-            dep.requirement.satisfied_by? installed_spec.version
+          dep.name == installed_spec.name &&
+            dep.requirement.satisfied_by?(installed_spec.version)
         end
 
-        unless inst or @specs.find {|s| s.satisfies_requirement? dep }
+        unless inst || @specs.find {|s| s.satisfies_requirement? dep }
           unsatisfied[spec.name] << dep
           return unsatisfied if quick
         end
@@ -175,7 +175,7 @@ class Gem::DependencyList
   def remove_specs_unsatisfied_by(dependencies)
     specs.reject! do |spec|
       dep = dependencies[spec.name]
-      dep and not dep.requirement.satisfied_by? spec.version
+      dep && !dep.requirement.satisfied_by?(spec.version)
     end
   end
 
diff --git a/lib/rubygems/doctor.rb b/lib/rubygems/doctor.rb
index 662eff9559..96829227fc 100644
--- a/lib/rubygems/doctor.rb
+++ b/lib/rubygems/doctor.rb
@@ -30,7 +30,7 @@ class Gem::Doctor
 
   missing =
     Gem::REPOSITORY_SUBDIRECTORIES.sort -
-      REPOSITORY_EXTENSION_MAP.map {|(k,_)| k }.sort
+    REPOSITORY_EXTENSION_MAP.map {|(k,_)| k }.sort
 
   raise "Update REPOSITORY_EXTENSION_MAP, missing: #{missing.join ', '}" unless
     missing.empty?
@@ -59,7 +59,7 @@ class Gem::Doctor
   # Are we doctoring a gem repository?
 
   def gem_repository?
-    not installed_specs.empty?
+    !installed_specs.empty?
   end
 
   ##
@@ -111,8 +111,8 @@ class Gem::Doctor
       basename = File.basename(child, extension)
       next if installed_specs.include? basename
       next if /^rubygems-\d/ =~ basename
-      next if "specifications" == sub_directory and "default" == basename
-      next if "plugins" == sub_directory and Gem.plugin_suffix_regexp =~ basename
+      next if "specifications" == sub_directory && "default" == basename
+      next if "plugins" == sub_directory && Gem.plugin_suffix_regexp =~ (basename)
 
       type = File.directory?(child) ? "directory" : "file"
 
diff --git a/lib/rubygems/exceptions.rb b/lib/rubygems/exceptions.rb
index 5fadbe9bca..974c0173b9 100644
--- a/lib/rubygems/exceptions.rb
+++ b/lib/rubygems/exceptions.rb
@@ -254,7 +254,7 @@ class Gem::UnsatisfiableDependencyError < Gem::DependencyError
   # Gem::Resolver::DependencyRequest +dep+
 
   def initialize(dep, platform_mismatch=nil)
-    if platform_mismatch and !platform_mismatch.empty?
+    if platform_mismatch && !platform_mismatch.empty?
       plats = platform_mismatch.map {|x| x.platform.to_s }.sort.uniq
       super "Unable to resolve dependency: No match for '#{dep}' on this platform. Found: #{plats.join(', ')}"
     else
diff --git a/lib/rubygems/ext/ext_conf_builder.rb b/lib/rubygems/ext/ext_conf_builder.rb
index f8920596d5..ebe398f56c 100644
--- a/lib/rubygems/ext/ext_conf_builder.rb
+++ b/lib/rubygems/ext/ext_conf_builder.rb
@@ -44,7 +44,7 @@ class Gem::Ext::ExtConfBuilder < Gem::Ext::Builder
       full_tmp_dest = File.join(extension_dir, tmp_dest_relative)
 
       # TODO remove in RubyGems 4
-      if Gem.install_extension_in_lib and lib_dir
+      if Gem.install_extension_in_lib && lib_dir
         FileUtils.mkdir_p lib_dir
         entries = Dir.entries(full_tmp_dest) - %w[. ..]
         entries = entries.map {|entry| File.join full_tmp_dest, entry }
@@ -53,7 +53,7 @@ class Gem::Ext::ExtConfBuilder < Gem::Ext::Builder
 
       FileUtils::Entry_.new(full_tmp_dest).traverse do |ent|
         destent = ent.class.new(dest_path, ent.rel)
-        destent.exist? or FileUtils.mv(ent.path, destent.path)
+        destent.exist? || FileUtils.mv(ent.path, destent.path)
       end
     ensure
       ENV["DESTDIR"] = destdir
diff --git a/lib/rubygems/gemcutter_utilities.rb b/lib/rubygems/gemcutter_utilities.rb
index c46650afb1..a785159196 100644
--- a/lib/rubygems/gemcutter_utilities.rb
+++ b/lib/rubygems/gemcutter_utilities.rb
@@ -71,7 +71,7 @@ module Gem::GemcutterUtilities
       begin
         env_rubygems_host = ENV["RUBYGEMS_HOST"]
         env_rubygems_host = nil if
-          env_rubygems_host and env_rubygems_host.empty?
+          env_rubygems_host && env_rubygems_host.empty?
 
         env_rubygems_host || configured_host
       end
diff --git a/lib/rubygems/indexer.rb b/lib/rubygems/indexer.rb
index 2299932f45..39653462e9 100644
--- a/lib/rubygems/indexer.rb
+++ b/lib/rubygems/indexer.rb
@@ -149,7 +149,7 @@ class Gem::Indexer
             next
           end
 
-          platform = Gem::Platform::RUBY if platform.nil? or platform.empty?
+          platform = Gem::Platform::RUBY if platform.nil? || platform.empty?
           [spec.name, spec.version, platform]
         end
 
@@ -296,7 +296,7 @@ class Gem::Indexer
     files = @files
     files.delete @quick_marshal_dir if files.include? @quick_dir
 
-    if files.include? @quick_marshal_dir and not files.include? @quick_dir
+    if files.include?(@quick_marshal_dir) && !files.include?(@quick_dir)
       files.delete @quick_marshal_dir
 
       dst_name = File.join(@dest_directory, @quick_marshal_dir_base)
@@ -414,7 +414,7 @@ class Gem::Indexer
 
     index.each do |spec|
       platform = spec.original_platform
-      platform = Gem::Platform::RUBY if platform.nil? or platform.empty?
+      platform = Gem::Platform::RUBY if platform.nil? || platform.empty?
       specs_index << [spec.name, spec.version, platform]
     end
 
diff --git a/lib/rubygems/installer.rb b/lib/rubygems/installer.rb
index 52307f6d93..2e29c38751 100644
--- a/lib/rubygems/installer.rb
+++ b/lib/rubygems/installer.rb
@@ -251,7 +251,7 @@ class Gem::Installer
     return if spec.name == existing
 
     # somebody has written to RubyGems' directory, overwrite, too bad
-    return if Gem.default_bindir != @bin_dir and not ruby_executable
+    return if Gem.default_bindir != @bin_dir && !ruby_executable
 
     question = "#{spec.name}'s executable \"#{filename}\" conflicts with ".dup
 
@@ -418,10 +418,10 @@ class Gem::Installer
   # True if the gems in the system satisfy +dependency+.
 
   def installation_satisfies_dependency?(dependency)
-    return true if @options[:development] and dependency.type == :development
+    return true if @options[:development] && dependency.type == :development
     return true if installed_specs.detect {|s| dependency.matches_spec? s }
     return false if @only_install_dir
-    not dependency.matching_specs.empty?
+    !dependency.matching_specs.empty?
   end
 
   ##
@@ -483,22 +483,14 @@ class Gem::Installer
   end
 
   def generate_bin # :nodoc:
-    return if spec.executables.nil? or spec.executables.empty?
+    return if spec.executables.nil? || spec.executables.empty?
 
     ensure_writable_dir @bin_dir
 
     spec.executables.each do |filename|
       filename.tap(&Gem::UNTAINT)
       bin_path = File.join gem_dir, spec.bindir, filename
-
-      unless File.exist? bin_path
-        if File.symlink? bin_path
-          alert_warning "`#{bin_path}` is dangling symlink pointing to `#{File.readlink bin_path}`"
-        else
-          alert_warning "`#{bin_path}` does not exist, maybe `gem pristine #{spec.name}` will fix it?"
-        end
-        next
-      end
+      next unless File.exist? bin_path
 
       mode = File.stat(bin_path).mode
       dir_mode = options[:prog_mode] || (mode | 0111)
diff --git a/lib/rubygems/name_tuple.rb b/lib/rubygems/name_tuple.rb
index b9f330ee4d..767dc1fb45 100644
--- a/lib/rubygems/name_tuple.rb
+++ b/lib/rubygems/name_tuple.rb
@@ -10,7 +10,7 @@ class Gem::NameTuple
     @version = version
 
     unless platform.kind_of? Gem::Platform
-      platform = "ruby" if !platform or platform.empty?
+      platform = "ruby" if !platform || platform.empty?
     end
 
     @platform = platform
@@ -102,8 +102,8 @@ class Gem::NameTuple
   def ==(other)
     case other
     when self.class
-      @name == other.name and
-        @version == other.version and
+      @name == other.name &&
+        @version == other.version &&
         @platform == other.platform
     when Array
       to_a == other
diff --git a/lib/rubygems/package.rb b/lib/rubygems/package.rb
index 1e87837b0e..084dc5d2d9 100644
--- a/lib/rubygems/package.rb
+++ b/lib/rubygems/package.rb
@@ -68,14 +68,14 @@ class Gem::Package
   class PathError < Error
     def initialize(destination, destination_dir)
       super "installing into parent path %s of %s is not allowed" %
-              [destination, destination_dir]
+        [destination, destination_dir]
     end
   end
 
   class SymlinkError < Error
     def initialize(name, destination, destination_dir)
       super "installing symlink '%s' pointing to parent path %s of %s is not allowed" %
-              [name, destination, destination_dir]
+        [name, destination, destination_dir]
     end
   end
 
@@ -409,18 +409,23 @@ EOM
 
   def extract_tar_gz(io, destination_dir, pattern = "*") # :nodoc:
     directories = []
+    symlinks = []
+
     open_tar_gz io do |tar|
       tar.each do |entry|
-        next unless File.fnmatch pattern, entry.full_name, File::FNM_DOTMATCH
+        full_name = entry.full_name
+        next unless File.fnmatch pattern, full_name, File::FNM_DOTMATCH
 
-        destination = install_location entry.full_name, destination_dir
+        destination = install_location full_name, destination_dir
 
         if entry.symlink?
           link_target = entry.header.linkname
           real_destination = link_target.start_with?("/") ? link_target : File.expand_path(link_target, File.dirname(destination))
 
-          raise Gem::Package::SymlinkError.new(entry.full_name, real_destination, destination_dir) unless
+          raise Gem::Package::SymlinkError.new(full_name, real_destination, destination_dir) unless
             normalize_path(real_destination).start_with? normalize_path(destination_dir + "/")
+
+          symlinks << [full_name, link_target, destination, real_destination]
         end
 
         FileUtils.rm_rf destination
@@ -444,12 +449,18 @@ EOM
           FileUtils.chmod file_mode(entry.header.mode), destination
         end if entry.file?
 
-        File.symlink(entry.header.linkname, destination) if entry.symlink?
-
         verbose destination
       end
     end
 
+    symlinks.each do |name, target, destination, real_destination|
+      if File.exist?(real_destination)
+        File.symlink(target, destination)
+      else
+        alert_warning "#{@spec.full_name} ships with a dangling symlink named #{name} pointing to missing #{target} file. Ignoring"
+      end
+    end
+
     if dir_mode
       File.chmod(dir_mode, *directories)
     end
@@ -676,7 +687,7 @@ EOM
               "package content (data.tar.gz) is missing", @gem
     end
 
-    if duplicates = @files.group_by {|f| f }.select {|k,v| v.size > 1 }.map(&:first) and duplicates.any?
+    if (duplicates = @files.group_by {|f| f }.select {|k,v| v.size > 1 }.map(&:first)) && duplicates.any?
       raise Gem::Security::Exception, "duplicate files in the package: (#{duplicates.map(&:inspect).join(', ')})"
     end
   end
diff --git a/lib/rubygems/package/tar_header.rb b/lib/rubygems/package/tar_header.rb
index fb70765dde..ee515a9e05 100644
--- a/lib/rubygems/package/tar_header.rb
+++ b/lib/rubygems/package/tar_header.rb
@@ -173,23 +173,23 @@ class Gem::Package::TarHeader
   end
 
   def ==(other) # :nodoc:
-    self.class === other and
-    @checksum == other.checksum and
-    @devmajor == other.devmajor and
-    @devminor == other.devminor and
-    @gid      == other.gid      and
-    @gname    == other.gname    and
-    @linkname == other.linkname and
-    @magic    == other.magic    and
-    @mode     == other.mode     and
-    @mtime    == other.mtime    and
-    @name     == other.name     and
-    @prefix   == other.prefix   and
-    @size     == other.size     and
-    @typeflag == other.typeflag and
-    @uid      == other.uid      and
-    @uname    == other.uname    and
-    @version  == other.version
+    self.class === other &&
+      @checksum == other.checksum &&
+      @devmajor == other.devmajor &&
+      @devminor == other.devminor &&
+      @gid      == other.gid      &&
+      @gname    == other.gname    &&
+      @linkname == other.linkname &&
+      @magic    == other.magic    &&
+      @mode     == other.mode     &&
+      @mtime    == other.mtime    &&
+      @name     == other.name     &&
+      @prefix   == other.prefix   &&
+      @size     == other.size     &&
+      @typeflag == other.typeflag &&
+      @uid      == other.uid      &&
+      @uname    == other.uname    &&
+      @version  == other.version
   end
 
   def to_s # :nodoc:
diff --git a/lib/rubygems/package/tar_writer.rb b/lib/rubygems/package/tar_writer.rb
index 6f068f50c2..db5242c5e4 100644
--- a/lib/rubygems/package/tar_writer.rb
+++ b/lib/rubygems/package/tar_writer.rb
@@ -314,7 +314,7 @@ class Gem::Package::TarWriter
         prefix = parts.join("/")
       end
 
-      if name.bytesize > 100 or prefix.empty?
+      if name.bytesize > 100 || prefix.empty?
         raise Gem::Package::TooLongFileName.new("File \"#{prefix}/#{name}\" has a too long name (should be 100 or less)")
       end
 
diff --git a/lib/rubygems/platform.rb b/lib/rubygems/platform.rb
index 607e3906d6..ed3571dbff 100644
--- a/lib/rubygems/platform.rb
+++ b/lib/rubygems/platform.rb
@@ -23,9 +23,9 @@ class Gem::Platform
 
   def self.match_platforms?(platform, platforms)
     platforms.any? do |local_platform|
-      platform.nil? or
-        local_platform == platform or
-        (local_platform != Gem::Platform::RUBY and local_platform =~ platform)
+      platform.nil? ||
+        local_platform == platform ||
+        (local_platform != Gem::Platform::RUBY && local_platform =~ platform)
     end
   end
   private_class_method :match_platforms?
@@ -70,7 +70,7 @@ class Gem::Platform
     when String then
       arch = arch.split "-"
 
-      if arch.length > 2 and arch.last !~ /\d/ # reassemble x86-linux-gnu
+      if arch.length > 2 && arch.last !~ (/\d/) # reassemble x86-linux-gnu
         extra = arch.pop
         arch.last << "-#{extra}"
       end
@@ -82,7 +82,7 @@ class Gem::Platform
       else cpu
       end
 
-      if arch.length == 2 and arch.last =~ /^\d+(\.\d+)?$/ # for command-line
+      if arch.length == 2 && arch.last =~ /^\d+(\.\d+)?$/ # for command-line
         @os, @version = arch
         return
       end
@@ -107,7 +107,7 @@ class Gem::Platform
       when /mingw-?(\w+)?/ then         [ "mingw",     $1  ]
       when /(mswin\d+)(\_(\d+))?/ then
         os, version = $1, $3
-        @cpu = "x86" if @cpu.nil? and os =~ /32$/
+        @cpu = "x86" if @cpu.nil? && os =~ /32$/
         [os, version]
       when /netbsdelf/ then             [ "netbsdelf", nil ]
       when /openbsd(\d+\.\d+)?/ then    [ "openbsd",   $1  ]
@@ -139,7 +139,7 @@ class Gem::Platform
   # the same CPU, OS and version.
 
   def ==(other)
-    self.class === other and to_a == other.to_a
+    self.class === other && to_a == other.to_a
   end
 
   alias :eql? :==
@@ -160,18 +160,18 @@ class Gem::Platform
     return nil unless Gem::Platform === other
 
     # universal-mingw32 matches x64-mingw-ucrt
-    return true if (@cpu == "universal" or other.cpu == "universal") and
-                   @os.start_with?("mingw") and other.os.start_with?("mingw")
+    return true if (@cpu == "universal" || other.cpu == "universal") &&
+                   @os.start_with?("mingw") && other.os.start_with?("mingw")
 
     # cpu
-    ([nil,"universal"].include?(@cpu) or [nil, "universal"].include?(other.cpu) or @cpu == other.cpu or
-    (@cpu == "arm" and other.cpu.start_with?("arm"))) and
+    ([nil,"universal"].include?(@cpu) || [nil, "universal"].include?(other.cpu) || @cpu == other.cpu ||
+    (@cpu == "arm" && other.cpu.start_with?("arm"))) &&
 
-    # os
-    @os == other.os and
+      # os
+      @os == other.os &&
 
-    # version
-    (@version.nil? or other.version.nil? or @version == other.version)
+      # version
+      (@version.nil? || other.version.nil? || @version == other.version)
   end
 
   ##
diff --git a/lib/rubygems/query_utils.rb b/lib/rubygems/query_utils.rb
index 4601d9374c..a502717f94 100644
--- a/lib/rubygems/query_utils.rb
+++ b/lib/rubygems/query_utils.rb
@@ -112,7 +112,7 @@ module Gem::QueryUtils
   end
 
   def display_header(type)
-    if (ui.outs.tty? and Gem.configuration.verbose) or both?
+    if (ui.outs.tty? && Gem.configuration.verbose) || both?
       say
       say "*** #{type} GEMS ***"
       say
@@ -132,7 +132,7 @@ module Gem::QueryUtils
       name_matches = name ? s.name =~ name : true
       version_matches = show_prereleases? || !s.version.prerelease?
 
-      name_matches and version_matches
+      name_matches && version_matches
     end
 
     spec_tuples = specs.map do |spec|
@@ -176,7 +176,7 @@ module Gem::QueryUtils
   # Check if gem +name+ version +version+ is installed.
 
   def installed?(name, req = Gem::Requirement.default)
-    Gem::Specification.any? {|s| s.name =~ name and req =~ s.version }
+    Gem::Specification.any? {|s| s.name =~ name && req =~ s.version }
   end
 
   def output_query_results(spec_tuples)
@@ -242,7 +242,7 @@ module Gem::QueryUtils
     return unless options[:versions]
 
     list =
-      if platforms.empty? or options[:details]
+      if platforms.empty? || options[:details]
         name_tuples.map {|n| n.version }.uniq
       else
         platforms.sort.reverse.map do |version, pls|
@@ -289,13 +289,13 @@ module Gem::QueryUtils
   end
 
   def spec_homepage(entry, spec)
-    return if spec.homepage.nil? or spec.homepage.empty?
+    return if spec.homepage.nil? || spec.homepage.empty?
 
     entry << "\n" << format_text("Homepage: #{spec.homepage}", 68, 4)
   end
 
   def spec_license(entry, spec)
-    return if spec.license.nil? or spec.license.empty?
+    return if spec.license.nil? || spec.license.empty?
 
     licenses = "License#{spec.licenses.length > 1 ? 's' : ''}: ".dup
     licenses << spec.licenses.join(", ")
diff --git a/lib/rubygems/remote_fetcher.rb b/lib/rubygems/remote_fetcher.rb
index d028739861..0ac6eaa130 100644
--- a/lib/rubygems/remote_fetcher.rb
+++ b/lib/rubygems/remote_fetcher.rb
@@ -114,7 +114,7 @@ class Gem::RemoteFetcher
     cache_dir =
       if Dir.pwd == install_dir # see fetch_command
         install_dir
-      elsif File.writable?(install_cache_dir) || (File.writable?(install_dir) && (not File.exist?(install_cache_dir)))
+      elsif File.writable?(install_cache_dir) || (File.writable?(install_dir) && (!File.exist?(install_cache_dir)))
         install_cache_dir
       else
         File.join Gem.user_dir, "cache"
@@ -247,7 +247,7 @@ class Gem::RemoteFetcher
 
     data = send "fetch_#{uri.scheme}", uri, mtime, head
 
-    if data and !head and uri.to_s.end_with?(".gz")
+    if data && !head && uri.to_s.end_with?(".gz")
       begin
         data = Gem::Util.gunzip data
       rescue Zlib::GzipFile::Error
@@ -288,7 +288,7 @@ class Gem::RemoteFetcher
       return Gem.read_binary(path)
     end
 
-    if update and path
+    if update && path
       Gem.write_binary(path, data)
     end
 
diff --git a/lib/rubygems/request.rb b/lib/rubygems/request.rb
index d15ba91209..c3ea46e0eb 100644
--- a/lib/rubygems/request.rb
+++ b/lib/rubygems/request.rb
@@ -173,7 +173,7 @@ class Gem::Request
     require "uri"
     uri = URI(Gem::UriFormatter.new(env_proxy).normalize)
 
-    if uri and uri.user.nil? and uri.password.nil?
+    if uri && uri.user.nil? && uri.password.nil?
       user     = ENV["#{_scheme}_proxy_user"] || ENV["#{_SCHEME}_PROXY_USER"]
       password = ENV["#{_scheme}_proxy_pass"] || ENV["#{_SCHEME}_PROXY_PASS"]
 
diff --git a/lib/rubygems/request/connection_pools.rb b/lib/rubygems/request/connection_pools.rb
index a283267674..44280489fb 100644
--- a/lib/rubygems/request/connection_pools.rb
+++ b/lib/rubygems/request/connection_pools.rb
@@ -39,7 +39,7 @@ class Gem::Request::ConnectionPools # :nodoc:
   def get_no_proxy_from_env
     env_no_proxy = ENV["no_proxy"] || ENV["NO_PROXY"]
 
-    return [] if env_no_proxy.nil? or env_no_proxy.empty?
+    return [] if env_no_proxy.nil? || env_no_proxy.empty?
 
     env_no_proxy.split(/\s*,\s*/)
   end
@@ -78,7 +78,7 @@ class Gem::Request::ConnectionPools # :nodoc:
 
     no_proxy = get_no_proxy_from_env
 
-    if proxy_uri and not no_proxy?(hostname, no_proxy)
+    if proxy_uri && !no_proxy?(hostname, no_proxy)
       proxy_hostname = proxy_uri.respond_to?(:hostname) ? proxy_uri.hostname : proxy_uri.host
       net_http_args + [
         proxy_hostname,
diff --git a/lib/rubygems/request/http_pool.rb b/lib/rubygems/request/http_pool.rb
index f028516db8..7b309eedd3 100644
--- a/lib/rubygems/request/http_pool.rb
+++ b/lib/rubygems/request/http_pool.rb
@@ -26,7 +26,7 @@ class Gem::Request::HTTPPool # :nodoc:
 
   def close_all
     until @queue.empty?
-      if connection = @queue.pop(true) and connection.started?
+      if (connection = @queue.pop(true)) && connection.started?
         connection.finish
       end
     end
diff --git a/lib/rubygems/request_set.rb b/lib/rubygems/request_set.rb
index df215e4af3..64701a8214 100644
--- a/lib/rubygems/request_set.rb
+++ b/lib/rubygems/request_set.rb
@@ -443,14 +443,14 @@ class Gem::RequestSet
 
   def tsort_each_child(node) # :nodoc:
     node.spec.dependencies.each do |dep|
-      next if dep.type == :development and not @development
+      next if dep.type == :development && !@development
 
       match = @requests.find do |r|
-        dep.match? r.spec.name, r.spec.version, @prerelease
+        dep.match? r.spec.name, r.spec.version, r.spec.is_a?(Gem::Resolver::InstalledSpecification) || @prerelease
       end
 
       unless match
-        next if dep.type == :development and @development_shallow
+        next if dep.type == :development && @development_shallow
         next if @soft_missing
         raise Gem::DependencyError,
               "Unresolved dependency found during sorting - #{dep} (requested by #{node.spec.full_name})"
diff --git a/lib/rubygems/request_set/gem_dependency_api.rb b/lib/rubygems/request_set/gem_dependency_api.rb
index 568d9f952f..fe75ac5208 100644
--- a/lib/rubygems/request_set/gem_dependency_api.rb
+++ b/lib/rubygems/request_set/gem_dependency_api.rb
@@ -371,7 +371,7 @@ class Gem::RequestSet::GemDependencyAPI
     duplicate = @dependencies.include? name
 
     @dependencies[name] =
-      if requirements.empty? and not source_set
+      if requirements.empty? && !source_set
         Gem::Requirement.default
       elsif source_set
         Gem::Requirement.source_set
@@ -789,7 +789,7 @@ Gem dependencies file #{@path} includes git reference for both ref/branch and ta
 
     raise ArgumentError,
           "You must specify engine_version along with the Ruby engine" if
-            engine and not engine_version
+            engine && !engine_version
 
     return true if @installing
 
@@ -800,7 +800,7 @@ Gem dependencies file #{@path} includes git reference for both ref/branch and ta
       raise Gem::RubyVersionMismatch, message
     end
 
-    if engine and engine != Gem.ruby_engine
+    if engine && engine != Gem.ruby_engine
       message = "Your Ruby engine is #{Gem.ruby_engine}, " +
                 "but your #{gem_deps_file} requires #{engine}"
 
diff --git a/lib/rubygems/request_set/lockfile/parser.rb b/lib/rubygems/request_set/lockfile/parser.rb
index 376d37f9e2..8446f9df8e 100644
--- a/lib/rubygems/request_set/lockfile/parser.rb
+++ b/lib/rubygems/request_set/lockfile/parser.rb
@@ -30,7 +30,7 @@ class Gem::RequestSet::Lockfile::Parser
         when "PLATFORMS" then
           parse_PLATFORMS
         else
-          token = get until @tokens.empty? or peek.first == :section
+          token = get until @tokens.empty? || peek.first == :section
         end
       else
         raise "BUG: unhandled token #{token.type} (#{token.value.inspect}) at line #{token.line} column #{token.column}"
@@ -44,7 +44,7 @@ class Gem::RequestSet::Lockfile::Parser
   def get(expected_types = nil, expected_value = nil) # :nodoc:
     token = @tokens.shift
 
-    if expected_types and not Array(expected_types).include? token.type
+    if expected_types && !Array(expected_types).include?(token.type)
       unget token
 
       message = "unexpected token [#{token.type.inspect}, #{token.value.inspect}], " +
@@ -53,7 +53,7 @@ class Gem::RequestSet::Lockfile::Parser
       raise Gem::RequestSet::Lockfile::ParseError.new message, token.column, token.line, @filename
     end
 
-    if expected_value and expected_value != token.value
+    if expected_value && expected_value != token.value
       unget token
 
       message = "unexpected token [#{token.type.inspect}, #{token.value.inspect}], " +
@@ -67,7 +67,7 @@ class Gem::RequestSet::Lockfile::Parser
   end
 
   def parse_DEPENDENCIES # :nodoc:
-    while not @tokens.empty? and :text == peek.type do
+    while !@tokens.empty? && :text == peek.type do
       token = get :text
 
       requirements = []
@@ -127,7 +127,7 @@ class Gem::RequestSet::Lockfile::Parser
     set = Gem::Resolver::LockSet.new sources
     last_specs = nil
 
-    while not @tokens.empty? and :text == peek.type do
+    while !@tokens.empty? && :text == peek.type do
       token = get :text
       name = token.value
       column = token.column
@@ -144,7 +144,7 @@ class Gem::RequestSet::Lockfile::Parser
         type = token.type
         data = token.value
 
-        if type == :text and column == 4
+        if type == :text && column == 4
           version, platform = data.split "-", 2
 
           platform =
@@ -183,7 +183,7 @@ class Gem::RequestSet::Lockfile::Parser
 
     type = peek.type
     value = peek.value
-    if type == :entry and %w[branch ref tag].include? value
+    if type == :entry && %w[branch ref tag].include?(value)
       get
       get :text
 
@@ -199,7 +199,7 @@ class Gem::RequestSet::Lockfile::Parser
 
     last_spec = nil
 
-    while not @tokens.empty? and :text == peek.type do
+    while !@tokens.empty? && :text == peek.type do
       token = get :text
       name = token.value
       column = token.column
@@ -214,7 +214,7 @@ class Gem::RequestSet::Lockfile::Parser
         type = token.type
         data = token.value
 
-        if type == :text and column == 4
+        if type == :text && column == 4
           last_spec = set.add_git_spec name, data, repository, revision, true
         else
           dependency = parse_dependency name, data
@@ -246,7 +246,7 @@ class Gem::RequestSet::Lockfile::Parser
     set = Gem::Resolver::VendorSet.new
     last_spec = nil
 
-    while not @tokens.empty? and :text == peek.first do
+    while !@tokens.empty? && :text == peek.first do
       token = get :text
       name = token.value
       column = token.column
@@ -261,7 +261,7 @@ class Gem::RequestSet::Lockfile::Parser
         type = token.type
         data = token.value
 
-        if type == :text and column == 4
+        if type == :text && column == 4
           last_spec = set.add_vendor_gem name, directory
         else
           dependency = parse_dependency name, data
@@ -281,7 +281,7 @@ class Gem::RequestSet::Lockfile::Parser
   end
 
   def parse_PLATFORMS # :nodoc:
-    while not @tokens.empty? and :text == peek.first do
+    while !@tokens.empty? && :text == peek.first do
       name = get(:text).value
 
       @platforms << name
diff --git a/lib/rubygems/request_set/lockfile/tokenizer.rb b/lib/rubygems/request_set/lockfile/tokenizer.rb
index 79c573a02d..4476a041c4 100644
--- a/lib/rubygems/request_set/lockfile/tokenizer.rb
+++ b/lib/rubygems/request_set/lockfile/tokenizer.rb
@@ -1,4 +1,4 @@
-# frozen_string_literal: true
+#) frozen_string_literal: true
 require_relative "parser"
 
 class Gem::RequestSet::Lockfile::Tokenizer
@@ -26,7 +26,7 @@ class Gem::RequestSet::Lockfile::Tokenizer
   end
 
   def skip(type)
-    @tokens.shift while not @tokens.empty? and peek.type == type
+    @tokens.shift while !@tokens.empty? && peek.type == type
   end
 
   ##
diff --git a/lib/rubygems/requirement.rb b/lib/rubygems/requirement.rb
index 12bf371f4e..4f19b8c5b0 100644
--- a/lib/rubygems/requirement.rb
+++ b/lib/rubygems/requirement.rb
@@ -253,7 +253,7 @@ class Gem::Requirement
   def specific?
     return true if @requirements.length > 1 # GIGO, > 1, > 2 is silly
 
-    not %w[> >=].include? @requirements.first.first # grab the operator
+    !%w[> >=].include? @requirements.first.first # grab the operator
   end
 
   def to_s # :nodoc:
diff --git a/lib/rubygems/resolver.rb b/lib/rubygems/resolver.rb
index 097e8243ee..bf7d6d943b 100644
--- a/lib/rubygems/resolver.rb
+++ b/lib/rubygems/resolver.rb
@@ -153,10 +153,10 @@ class Gem::Resolver
     s.fetch_development_dependencies if @development
 
     s.dependencies.reverse_each do |d|
-      next if d.type == :development and not @development
-      next if d.type == :development and @development_shallow and
+      next if d.type == :development && !@development
+      next if d.type == :development && @development_shallow &&
               act.development?
-      next if d.type == :development and @development_shallow and
+      next if d.type == :development && @development_shallow &&
               act.parent
 
       reqs << Gem::Resolver::DependencyRequest.new(d, act)
@@ -192,7 +192,7 @@ class Gem::Resolver
     conflict = e.conflicts.values.first
     raise Gem::DependencyResolutionError, Conflict.new(conflict.requirement_trees.first.first, conflict.existing, conflict.requirement)
   ensure
-    @output.close if defined?(@output) and !debug?
+    @output.close if defined?(@output) && !debug?
   end
 
   ##
diff --git a/lib/rubygems/resolver/api_specification.rb b/lib/rubygems/resolver/api_specification.rb
index 7af4d9cff3..1e65d5e5a9 100644
--- a/lib/rubygems/resolver/api_specification.rb
+++ b/lib/rubygems/resolver/api_specification.rb
@@ -40,10 +40,10 @@ class Gem::Resolver::APISpecification < Gem::Resolver::Specification
   end
 
   def ==(other) # :nodoc:
-    self.class === other and
-      @set          == other.set and
-      @name         == other.name and
-      @version      == other.version and
+    self.class === other &&
+      @set          == other.set &&
+      @name         == other.name &&
+      @version      == other.version &&
       @platform     == other.platform
   end
 
diff --git a/lib/rubygems/resolver/best_set.rb b/lib/rubygems/resolver/best_set.rb
index ab91ebca08..075ee1ef5c 100644
--- a/lib/rubygems/resolver/best_set.rb
+++ b/lib/rubygems/resolver/best_set.rb
@@ -25,7 +25,7 @@ class Gem::Resolver::BestSet < Gem::Resolver::ComposedSet
   end
 
   def find_all(req) # :nodoc:
-    pick_sets if @remote and @sets.empty?
+    pick_sets if @remote && @sets.empty?
 
     super
   rescue Gem::RemoteFetcher::FetchError => e
@@ -35,7 +35,7 @@ class Gem::Resolver::BestSet < Gem::Resolver::ComposedSet
   end
 
   def prefetch(reqs) # :nodoc:
-    pick_sets if @remote and @sets.empty?
+    pick_sets if @remote && @sets.empty?
 
     super
   end
@@ -63,7 +63,7 @@ class Gem::Resolver::BestSet < Gem::Resolver::ComposedSet
     uri = uri + "."
 
     raise error unless api_set = @sets.find do |set|
-      Gem::Resolver::APISet === set and set.dep_uri == uri
+      Gem::Resolver::APISet === set && set.dep_uri == uri
     end
 
     index_set = Gem::Resolver::IndexSet.new api_set.source
diff --git a/lib/rubygems/resolver/conflict.rb b/lib/rubygems/resolver/conflict.rb
index 54a7ca4641..aba6d73ea7 100644
--- a/lib/rubygems/resolver/conflict.rb
+++ b/lib/rubygems/resolver/conflict.rb
@@ -27,9 +27,9 @@ class Gem::Resolver::Conflict
   end
 
   def ==(other) # :nodoc:
-    self.class === other and
-      @dependency == other.dependency and
-      @activated  == other.activated  and
+    self.class === other &&
+      @dependency == other.dependency &&
+      @activated  == other.activated  &&
       @failed_dep == other.failed_dep
   end
 
diff --git a/lib/rubygems/resolver/git_specification.rb b/lib/rubygems/resolver/git_specification.rb
index d1e04737da..6a178ea82e 100644
--- a/lib/rubygems/resolver/git_specification.rb
+++ b/lib/rubygems/resolver/git_specification.rb
@@ -6,9 +6,9 @@
 
 class Gem::Resolver::GitSpecification < Gem::Resolver::SpecSpecification
   def ==(other) # :nodoc:
-    self.class === other and
-      @set  == other.set and
-      @spec == other.spec and
+    self.class === other &&
+      @set  == other.set &&
+      @spec == other.spec &&
       @source == other.source
   end
 
diff --git a/lib/rubygems/resolver/index_specification.rb b/lib/rubygems/resolver/index_specification.rb
index e8c3b35f7e..0fc758dfd3 100644
--- a/lib/rubygems/resolver/index_specification.rb
+++ b/lib/rubygems/resolver/index_specification.rb
@@ -21,7 +21,8 @@ class Gem::Resolver::IndexSpecification < Gem::Resolver::Specification
     @name = name
     @version = version
     @source = source
-    @platform = platform.to_s
+    @platform = Gem::Platform.new(platform.to_s)
+    @original_platform = platform.to_s
 
     @spec = nil
   end
@@ -91,7 +92,7 @@ class Gem::Resolver::IndexSpecification < Gem::Resolver::Specification
   def spec # :nodoc:
     @spec ||=
       begin
-        tuple = Gem::NameTuple.new @name, @version, @platform
+        tuple = Gem::NameTuple.new @name, @version, @original_platform
 
         @source.fetch_spec tuple
       end
diff --git a/lib/rubygems/resolver/installed_specification.rb b/lib/rubygems/resolver/installed_specification.rb
index 7c7ad8d85b..8932e068be 100644
--- a/lib/rubygems/resolver/installed_specification.rb
+++ b/lib/rubygems/resolver/installed_specification.rb
@@ -5,8 +5,8 @@
 
 class Gem::Resolver::InstalledSpecification < Gem::Resolver::SpecSpecification
   def ==(other) # :nodoc:
-    self.class === other and
-      @set  == other.set and
+    self.class === other &&
+      @set  == other.set &&
       @spec == other.spec
   end
 
diff --git a/lib/rubygems/resolver/installer_set.rb b/lib/rubygems/resolver/installer_set.rb
index 15580d7095..f663ce4ad5 100644
--- a/lib/rubygems/resolver/installer_set.rb
+++ b/lib/rubygems/resolver/installer_set.rb
@@ -61,13 +61,12 @@ class Gem::Resolver::InstallerSet < Gem::Resolver::Set
     found = find_all request
 
     found.delete_if do |s|
-      s.version.prerelease? and not s.local?
+      s.version.prerelease? && !s.local?
     end unless dependency.prerelease?
 
     found = found.select do |s|
-      Gem::Source::SpecificFile === s.source or
-        Gem::Platform::RUBY == s.platform or
-        Gem::Platform.local === s.platform
+      Gem::Source::SpecificFile === s.source ||
+        Gem::Platform.match(s.platform)
     end
 
     found = found.sort_by do |s|
@@ -111,14 +110,14 @@ class Gem::Resolver::InstallerSet < Gem::Resolver::Set
   # Should local gems should be considered?
 
   def consider_local? # :nodoc:
-    @domain == :both or @domain == :local
+    @domain == :both || @domain == :local
   end
 
   ##
   # Should remote gems should be considered?
 
   def consider_remote? # :nodoc:
-    @domain == :both or @domain == :remote
+    @domain == :both || @domain == :remote
   end
 
   ##
@@ -137,8 +136,8 @@ class Gem::Resolver::InstallerSet < Gem::Resolver::Set
 
     dep = req.dependency
 
-    return res if @ignore_dependencies and
-              @always_install.none? {|spec| dep.match? spec }
+    return res if @ignore_dependencies &&
+                  @always_install.none? {|spec| dep.match? spec }
 
     name = dep.name
 
@@ -168,10 +167,6 @@ class Gem::Resolver::InstallerSet < Gem::Resolver::Set
       end
     end
 
-    res.delete_if do |spec|
-      spec.version.prerelease? and not dep.prerelease?
-    end
-
     res.concat @remote_set.find_all req if consider_remote?
 
     res
diff --git a/lib/rubygems/resolver/lock_set.rb b/lib/rubygems/resolver/lock_set.rb
index ff6c6c912f..b1a5433cb5 100644
--- a/lib/rubygems/resolver/lock_set.rb
+++ b/lib/rubygems/resolver/lock_set.rb
@@ -54,7 +54,7 @@ class Gem::Resolver::LockSet < Gem::Resolver::Set
     dep = Gem::Dependency.new name, version
 
     found = @specs.find do |spec|
-      dep.matches_spec? spec and spec.platform == platform
+      dep.matches_spec?(spec) && spec.platform == platform
     end
 
     tuple = Gem::NameTuple.new found.name, found.version, found.platform
diff --git a/lib/rubygems/resolver/lock_specification.rb b/lib/rubygems/resolver/lock_specification.rb
index 4a30dcf849..7de2a14658 100644
--- a/lib/rubygems/resolver/lock_specification.rb
+++ b/lib/rubygems/resolver/lock_specification.rb
@@ -71,7 +71,7 @@ class Gem::Resolver::LockSpecification < Gem::Resolver::Specification
 
   def spec
     @spec ||= Gem::Specification.find do |spec|
-      spec.name == @name and spec.version == @version
+      spec.name == @name && spec.version == @version
     end
 
     @spec ||= Gem::Specification.new do |s|
diff --git a/lib/rubygems/resolver/vendor_specification.rb b/lib/rubygems/resolver/vendor_specification.rb
index 8dfe5940f2..600a98a2bf 100644
--- a/lib/rubygems/resolver/vendor_specification.rb
+++ b/lib/rubygems/resolver/vendor_specification.rb
@@ -6,9 +6,9 @@
 
 class Gem::Resolver::VendorSpecification < Gem::Resolver::SpecSpecification
   def ==(other) # :nodoc:
-    self.class === other and
-      @set  == other.set and
-      @spec == other.spec and
+    self.class === other &&
+      @set  == other.set &&
+      @spec == other.spec &&
       @source == other.source
   end
 
diff --git a/lib/rubygems/security.rb b/lib/rubygems/security.rb
index 4eb4023055..dd16283a98 100644
--- a/lib/rubygems/security.rb
+++ b/lib/rubygems/security.rb
@@ -618,7 +618,7 @@ module Gem::Security
     path = File.expand_path path
 
     File.open path, "wb", permissions do |io|
-      if passphrase and cipher
+      if passphrase && cipher
         io.write pemmable.to_pem cipher, passphrase
       else
         io.write pemmable.to_pem
diff --git a/lib/rubygems/security/policy.rb b/lib/rubygems/security/policy.rb
index 43588fd7f1..959880ddc1 100644
--- a/lib/rubygems/security/policy.rb
+++ b/lib/rubygems/security/policy.rb
@@ -88,16 +88,16 @@ class Gem::Security::Policy
 
     message = "certificate #{signer.subject}"
 
-    if not_before = signer.not_before and not_before > time
+    if (not_before = signer.not_before) && not_before > time
       raise Gem::Security::Exception,
             "#{message} not valid before #{not_before}"
     end
 
-    if not_after = signer.not_after and not_after < time
+    if (not_after = signer.not_after) && not_after < time
       raise Gem::Security::Exception, "#{message} not valid after #{not_after}"
     end
 
-    if issuer and not signer.verify issuer.public_key
+    if issuer && !signer.verify(issuer.public_key)
       raise Gem::Security::Exception,
             "#{message} was not issued by #{issuer.subject}"
     end
@@ -109,7 +109,7 @@ class Gem::Security::Policy
   # Ensures the public key of +key+ matches the public key in +signer+
 
   def check_key(signer, key)
-    unless signer and key
+    unless signer && key
       return true unless @only_signed
 
       raise Gem::Security::Exception, "missing key or signature"
@@ -231,7 +231,7 @@ class Gem::Security::Policy
 
     if @verify_data
       raise Gem::Security::Exception, "no digests provided (probable bug)" if
-        signer_digests.nil? or signer_digests.empty?
+        signer_digests.nil? || signer_digests.empty?
     else
       signer_digests = {}
     end
@@ -248,7 +248,7 @@ class Gem::Security::Policy
 
     if @only_trusted
       check_trust chain, digester, trust_dir
-    elsif signatures.empty? and digests.empty?
+    elsif signatures.empty? && digests.empty?
       # trust is irrelevant if there's no signatures to verify
     else
       alert_warning "#{subject signer} is not trusted for #{full_name}"
diff --git a/lib/rubygems/security/signer.rb b/lib/rubygems/security/signer.rb
index b1308c4e42..cca82f1cf8 100644
--- a/lib/rubygems/security/signer.rb
+++ b/lib/rubygems/security/signer.rb
@@ -141,7 +141,7 @@ class Gem::Security::Signer
 
     raise Gem::Security::Exception, "no certs provided" if @cert_chain.empty?
 
-    if @cert_chain.length == 1 and @cert_chain.last.not_after < Time.now
+    if @cert_chain.length == 1 && @cert_chain.last.not_after < Time.now
       alert("Your certificate has expired, trying to re-sign it...")
 
       re_sign_key(
diff --git a/lib/rubygems/source.rb b/lib/rubygems/source.rb
index 7c3b678645..fc72a1038a 100644
--- a/lib/rubygems/source.rb
+++ b/lib/rubygems/source.rb
@@ -62,7 +62,7 @@ class Gem::Source
   end
 
   def ==(other) # :nodoc:
-    self.class === other and @uri == other.uri
+    self.class === other && @uri == other.uri
   end
 
   alias_method :eql?, :== # :nodoc:
diff --git a/lib/rubygems/source/git.rb b/lib/rubygems/source/git.rb
index 22355adcfa..2609a309e8 100644
--- a/lib/rubygems/source/git.rb
+++ b/lib/rubygems/source/git.rb
@@ -76,10 +76,10 @@ class Gem::Source::Git < Gem::Source
   end
 
   def ==(other) # :nodoc:
-    super and
-      @name            == other.name and
-      @repository      == other.repository and
-      @reference       == other.reference and
+    super &&
+      @name            == other.name &&
+      @repository      == other.repository &&
+      @reference       == other.reference &&
       @need_submodules == other.need_submodules
   end
 
diff --git a/lib/rubygems/spec_fetcher.rb b/lib/rubygems/spec_fetcher.rb
index 43e7e05b63..0d06d1f144 100644
--- a/lib/rubygems/spec_fetcher.rb
+++ b/lib/rubygems/spec_fetcher.rb
@@ -98,7 +98,7 @@ class Gem::SpecFetcher
 
       found[source] = specs.select do |tup|
         if dependency.match?(tup)
-          if matching_platform and !Gem::Platform.match_gem?(tup.platform, tup.name)
+          if matching_platform && !Gem::Platform.match_gem?(tup.platform, tup.name)
             pm = (
               rejected_specs[dependency] ||= \
                 Gem::PlatformMismatch.new(tup.name, tup.version))
diff --git a/lib/rubygems/specification.rb b/lib/rubygems/specification.rb
index 00d139d854..82000bb75d 100644
--- a/lib/rubygems/specification.rb
+++ b/lib/rubygems/specification.rb
@@ -473,7 +473,7 @@ class Gem::Specification < Gem::BasicSpecification
   #   spec.platform = Gem::Platform.local
 
   def platform=(platform)
-    if @original_platform.nil? or
+    if @original_platform.nil? ||
        @original_platform == Gem::Platform::RUBY
       @original_platform = platform
     end
@@ -1046,7 +1046,7 @@ class Gem::Specification < Gem::BasicSpecification
 
   def self.find_active_stub_by_path(path)
     stub = @@active_stub_with_requirable_file[path] ||= (stubs.find do |s|
-      s.activated? and s.contains_requirable_file? path
+      s.activated? && s.contains_requirable_file?(path)
     end || NOT_FOUND)
     stub.this
   end
@@ -1234,7 +1234,7 @@ class Gem::Specification < Gem::BasicSpecification
       latest_remote = remotes.sort.last
 
       yield [local_spec, latest_remote] if
-        latest_remote and local_spec.version < latest_remote
+        latest_remote && local_spec.version < latest_remote
     end
 
     nil
@@ -1557,7 +1557,7 @@ class Gem::Specification < Gem::BasicSpecification
   # Singular reader for #authors.  Returns the first author in the list
 
   def author
-    val = authors and val.first
+    (val = authors) && val.first
   end
 
   ##
@@ -1669,7 +1669,7 @@ class Gem::Specification < Gem::BasicSpecification
     conflicts = {}
     self.runtime_dependencies.each do |dep|
       spec = Gem.loaded_specs[dep.name]
-      if spec and not spec.satisfies_requirement? dep
+      if spec && !spec.satisfies_requirement?(dep)
         (conflicts[spec] ||= []) << dep
       end
     end
@@ -1696,7 +1696,7 @@ class Gem::Specification < Gem::BasicSpecification
     self.dependencies.any? do |dep|
       if dep.runtime?
         spec = Gem.loaded_specs[dep.name]
-        spec and not spec.satisfies_requirement? dep
+        spec && !spec.satisfies_requirement?(dep)
       else
         false
       end
@@ -1717,7 +1717,7 @@ class Gem::Specification < Gem::BasicSpecification
 
   DateLike = Object.new # :nodoc:
   def DateLike.===(obj) # :nodoc:
-    defined?(::Date) and Date === obj
+    defined?(::Date) && Date === obj
   end
 
   DateTimeFormat = # :nodoc:
@@ -1757,9 +1757,9 @@ class Gem::Specification < Gem::BasicSpecification
   # executable now.  See Gem.bin_path.
 
   def default_executable # :nodoc:
-    if defined?(@default_executable) and @default_executable
+    if defined?(@default_executable) && @default_executable
       result = @default_executable
-    elsif @executables and @executables.size == 1
+    elsif @executables && @executables.size == 1
       result = Array(@executables).first
     else
       result = nil
@@ -1876,7 +1876,7 @@ class Gem::Specification < Gem::BasicSpecification
   # Singular accessor for #executables
 
   def executable
-    val = executables and val.first
+    (val = executables) && val.first
   end
 
   ##
@@ -1988,7 +1988,7 @@ class Gem::Specification < Gem::BasicSpecification
   # True if this gem has files in test_files
 
   def has_unit_tests? # :nodoc:
-    not test_files.empty?
+    !test_files.empty?
   end
 
   # :stopdoc:
@@ -2041,7 +2041,7 @@ class Gem::Specification < Gem::BasicSpecification
     self.name = name if name
     self.version = version if version
 
-    if platform = Gem.platforms.last and platform != Gem::Platform::RUBY and platform != Gem::Platform.local
+    if (platform = Gem.platforms.last) && platform != Gem::Platform::RUBY && platform != Gem::Platform.local
       self.platform = platform
     end
 
@@ -2156,8 +2156,8 @@ class Gem::Specification < Gem::BasicSpecification
       return
     end
 
-    if @specification_version > CURRENT_SPECIFICATION_VERSION and
-      sym.to_s.end_with?("=")
+    if @specification_version > CURRENT_SPECIFICATION_VERSION &&
+       sym.to_s.end_with?("=")
       warn "ignoring #{sym} loading #{full_name}" if $DEBUG
     else
       super
@@ -2183,7 +2183,7 @@ class Gem::Specification < Gem::BasicSpecification
   #   file list.
 
   def normalize
-    if defined?(@extra_rdoc_files) and @extra_rdoc_files
+    if defined?(@extra_rdoc_files) && @extra_rdoc_files
       @extra_rdoc_files.uniq!
       @files ||= []
       @files.concat(@extra_rdoc_files)
@@ -2208,7 +2208,7 @@ class Gem::Specification < Gem::BasicSpecification
   # platform.  For use with legacy gems.
 
   def original_name # :nodoc:
-    if platform == Gem::Platform::RUBY or platform.nil?
+    if platform == Gem::Platform::RUBY || platform.nil?
       "#{@name}-#{@version}"
     else
       "#{@name}-#{@version}-#{@original_platform}"
@@ -2241,8 +2241,8 @@ class Gem::Specification < Gem::BasicSpecification
       attributes.each do |attr_name|
         current_value = self.send attr_name
         current_value = current_value.sort if %i[files test_files].include? attr_name
-        if current_value != default_value(attr_name) or
-           self.class.required_attribute? attr_name
+        if current_value != default_value(attr_name) ||
+           self.class.required_attribute?(attr_name)
 
           q.text "s.#{attr_name} = "
 
@@ -2300,7 +2300,7 @@ class Gem::Specification < Gem::BasicSpecification
   # Singular accessor for #require_paths
 
   def require_path
-    val = require_paths and val.first
+    (val = require_paths) && val.first
   end
 
   ##
@@ -2375,7 +2375,7 @@ class Gem::Specification < Gem::BasicSpecification
 
   def satisfies_requirement?(dependency)
     return @name == dependency.name &&
-      dependency.requirement.satisfied_by?(@version)
+           dependency.requirement.satisfied_by?(@version)
   end
 
   ##
@@ -2429,7 +2429,7 @@ class Gem::Specification < Gem::BasicSpecification
   # Singular accessor for #test_files
 
   def test_file # :nodoc:
-    val = test_files and val.first
+    (val = test_files) && val.first
   end
 
   ##
@@ -2451,7 +2451,7 @@ class Gem::Specification < Gem::BasicSpecification
       @test_files = [@test_suite_file].flatten
       @test_suite_file = nil
     end
-    if defined?(@test_files) and @test_files
+    if defined?(@test_files) && @test_files
       @test_files
     else
       @test_files = []
@@ -2475,13 +2475,13 @@ class Gem::Specification < Gem::BasicSpecification
 
     result << "  s.name = #{ruby_code name}"
     result << "  s.version = #{ruby_code version}"
-    unless platform.nil? or platform == Gem::Platform::RUBY
+    unless platform.nil? || platform == Gem::Platform::RUBY
       result << "  s.platform = #{ruby_code original_platform}"
     end
     result << ""
     result << "  s.required_rubygems_version = #{ruby_code required_rubygems_version} if s.respond_to? :required_rubygems_version="
 
-    if metadata and !metadata.empty?
+    if metadata && !metadata.empty?
       result << "  s.metadata = #{ruby_code metadata} if s.respond_to? :metadata="
     end
     result << "  s.require_paths = #{ruby_code raw_require_paths}"
@@ -2665,6 +2665,8 @@ class Gem::Specification < Gem::BasicSpecification
 
   def version=(version)
     @version = Gem::Version.create(version)
+    return if @version.nil?
+
     # skip to set required_ruby_version when pre-released rubygems.
     # It caused to raise CircularDependencyError
     if @version.prerelease? && (@name.nil? || @name.strip != "rubygems")
diff --git a/lib/rubygems/specification_policy.rb b/lib/rubygems/specification_policy.rb
index 332189ae9f..44b31211e5 100644
--- a/lib/rubygems/specification_policy.rb
+++ b/lib/rubygems/specification_policy.rb
@@ -188,7 +188,7 @@ duplicate dependency on #{dep}, (#{prev.requirement}) use:
           prerelease_dep && !@specification.version.prerelease?
 
       open_ended = dep.requirement.requirements.all? do |op, version|
-        not version.prerelease? and (op == ">" or op == ">=")
+        !version.prerelease? && (op == ">" || op == ">=")
       end
 
       if open_ended
@@ -203,7 +203,7 @@ duplicate dependency on #{dep}, (#{prev.requirement}) use:
         else
           bugfix = if op == ">"
             ", '> #{dep_version}'"
-          elsif op == ">=" and base != segments
+          elsif op == ">=" && base != segments
             ", '>= #{dep_version}'"
           end
 
@@ -338,7 +338,7 @@ duplicate dependency on #{dep}, (#{prev.requirement}) use:
       String
     end
 
-    unless Array === val and val.all? {|x| x.kind_of?(klass) }
+    unless Array === val && val.all? {|x| x.kind_of?(klass) }
       error "#{field} must be an Array of #{klass}"
     end
   end
@@ -404,7 +404,7 @@ http://spdx.org/licenses or '#{Gem::Licenses::NONSTANDARD}' for a nonstandard li
     homepage = @specification.homepage
 
     # Make sure a homepage is valid HTTP/HTTPS URI
-    if homepage and not homepage.empty?
+    if homepage && !homepage.empty?
       require "uri"
       begin
         homepage_uri = URI.parse(homepage)
diff --git a/lib/rubygems/uninstaller.rb b/lib/rubygems/uninstaller.rb
index 1ae301a44d..5883ed1c41 100644
--- a/lib/rubygems/uninstaller.rb
+++ b/lib/rubygems/uninstaller.rb
@@ -105,8 +105,8 @@ class Gem::Uninstaller
     @default_specs_matching_uninstall_params = default_specs
 
     list, other_repo_specs = list.partition do |spec|
-      @gem_home == spec.base_dir or
-        (@user_install and spec.base_dir == Gem.user_dir)
+      @gem_home == spec.base_dir ||
+        (@user_install && spec.base_dir == Gem.user_dir)
     end
 
     list.sort!
@@ -239,8 +239,8 @@ class Gem::Uninstaller
   # spec:: the spec of the gem to be uninstalled
 
   def remove(spec)
-    unless path_ok?(@gem_home, spec) or
-           (@user_install and path_ok?(Gem.user_dir, spec))
+    unless path_ok?(@gem_home, spec) ||
+           (@user_install && path_ok?(Gem.user_dir, spec))
       e = Gem::GemNotInHomeException.new \
             "Gem '#{spec.full_name}' is not installed in directory #{@gem_home}"
       e.spec = spec
diff --git a/lib/rubygems/user_interaction.rb b/lib/rubygems/user_interaction.rb
index 4b0a7c60bb..2fa505423b 100644
--- a/lib/rubygems/user_interaction.rb
+++ b/lib/rubygems/user_interaction.rb
@@ -284,7 +284,7 @@ class Gem::StreamUI
   # Ask a question.  Returns an answer if connected to a tty, nil otherwise.
 
   def ask(question)
-    return nil if not tty?
+    return nil if !tty?
 
     @outs.print(question + "  ")
     @outs.flush
@@ -298,7 +298,7 @@ class Gem::StreamUI
   # Ask for a password. Does not echo response to terminal.
 
   def ask_for_password(question)
-    return nil if not tty?
+    return nil if !tty?
 
     @outs.print(question, "  ")
     @outs.flush
diff --git a/lib/rubygems/version.rb b/lib/rubygems/version.rb
index 03ae5ca17e..f67889ef1a 100644
--- a/lib/rubygems/version.rb
+++ b/lib/rubygems/version.rb
@@ -171,9 +171,7 @@ class Gem::Version
   # True if the +version+ string matches RubyGems' requirements.
 
   def self.correct?(version)
-    unless Gem::Deprecate.skip
-      warn "nil versions are discouraged and will be deprecated in Rubygems 4" if version.nil?
-    end
+    nil_versions_are_discouraged! if version.nil?
 
     !!(version.to_s =~ ANCHORED_VERSION_PATTERN)
   end
@@ -190,6 +188,8 @@ class Gem::Version
     if self === input # check yourself before you wreck yourself
       input
     elsif input.nil?
+      nil_versions_are_discouraged!
+
       nil
     else
       new input
@@ -206,6 +206,14 @@ class Gem::Version
     @@all[version] ||= super
   end
 
+  def self.nil_versions_are_discouraged!
+    unless Gem::Deprecate.skip
+      warn "nil versions are discouraged and will be deprecated in Rubygems 4"
+    end
+  end
+
+  private_class_method :nil_versions_are_discouraged!
+
   ##
   # Constructs a Version from the +version+ string.  A version string is a
   # series of digits or ASCII letters separated by dots.
@@ -244,7 +252,7 @@ class Gem::Version
   # same precision. Version "1.0" is not the same as version "1".
 
   def eql?(other)
-    self.class === other and @version == other._version
+    self.class === other && @version == other._version
   end
 
   def hash # :nodoc: