diff --git a/.rubocop.yml b/.rubocop.yml
index a408fa0d..27712bd8 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,6 +1,84 @@
-inherit_from:
-  - .rubocop_rubyzip.yml
+inherit_from: .rubocop_todo.yml
+
+# Set this to the minimum supported ruby in the gemspec. Otherwise
+# we get errors if our ruby version doesn't match.
 AllCops:
-  TargetRubyVersion: 1.9
-Style/MutableConstant:
-  Enabled: false # Because some existent code relies on mutable constant
+  TargetRubyVersion: 2.4
+
+Layout/HashAlignment:
+  EnforcedHashRocketStyle: table
+  EnforcedColonStyle: table
+
+# Set a workable line length, given the current state of the code,
+# and turn off for the tests.
+Layout/LineLength:
+  Max: 135
+  Exclude:
+    - 'test/**/*.rb'
+
+# In some cases we just need to catch an exception, rather than
+# actually handle it. Allow the tests to make use of this shortcut.
+Lint/SuppressedException:
+  AllowComments: true
+  Exclude:
+    - 'test/**/*.rb'
+
+# Allow this "useless" test, as we are testing <=> here.
+Lint/UselessComparison:
+  Exclude:
+    - 'test/entry_test.rb'
+
+# Turn off ABC metrics for the tests and set a workable max given
+# the current state of the code.
+Metrics/AbcSize:
+  Max: 37
+  Exclude:
+    - 'test/**/*.rb'
+
+# Turn block length metrics off for the tests.
+Metrics/BlockLength:
+  Exclude:
+    - 'test/**/*.rb'
+
+# Turn class length metrics off for the tests.
+Metrics/ClassLength:
+  Exclude:
+    - 'test/**/*.rb'
+
+# Turn method length metrics off for the tests.
+Metrics/MethodLength:
+  Exclude:
+    - 'test/**/*.rb'
+
+# Rubocop confuses these as instances of "memoization".
+Naming/MemoizedInstanceVariableName:
+  Exclude:
+    - 'lib/zip/extra_field/old_unix.rb'
+    - 'lib/zip/extra_field/unix.rb'
+
+# Set a consistent way of checking types.
+Style/ClassCheck:
+  EnforcedStyle: kind_of?
+
+# Allow this multi-line block chain as it actually reads better
+# than the alternatives.
+Style/MultilineBlockChain:
+  Exclude:
+    - 'lib/zip/crypto/traditional_encryption.rb'
+
+# Allow inner slashes when using // for regex literals. Allow the
+# Guardfile to use a syntax that is more consistent with its own style.
+Style/RegexpLiteral:
+  AllowInnerSlashes: true
+  Exclude:
+    - 'Guardfile'
+
+Style/SymbolArray:
+  EnforcedStyle: brackets
+
+# Turn this cop off for these files as it fires for objects without
+# an empty? method.
+Style/ZeroLengthPredicate:
+  Exclude:
+    - 'lib/zip/file.rb'
+    - 'lib/zip/input_stream.rb'
diff --git a/.rubocop_rubyzip.yml b/.rubocop_rubyzip.yml
deleted file mode 100644
index 3030f8a0..00000000
--- a/.rubocop_rubyzip.yml
+++ /dev/null
@@ -1,137 +0,0 @@
-# This configuration was generated by `rubocop --auto-gen-config`
-# on 2015-06-08 10:22:52 +0300 using RuboCop version 0.32.0.
-# The point is for the user to remove these configuration records
-# one by one as the offenses are removed from the code base.
-# Note that changes in the inspected code, or installation of new
-# versions of RuboCop, may require this file to be generated again.
-
-# Offense count: 13
-Lint/HandleExceptions:
-  Enabled: false
-
-# Offense count: 1
-Lint/LiteralInCondition:
-  Enabled: false
-
-# Offense count: 1
-Lint/RescueException:
-  Enabled: false
-
-# Offense count: 1
-Lint/UselessComparison:
-  Enabled: false
-
-# Offense count: 115
-Metrics/AbcSize:
-  Max: 62
-
-# Offense count: 12
-# Configuration parameters: CountComments.
-Metrics/ClassLength:
-  Max: 562
-
-# Offense count: 21
-Metrics/CyclomaticComplexity:
-  Max: 14
-
-# Offense count: 237
-# Configuration parameters: AllowURI, URISchemes.
-Metrics/LineLength:
-  Max: 236
-
-# Offense count: 108
-# Configuration parameters: CountComments.
-Metrics/MethodLength:
-  Max: 35
-
-# Offense count: 2
-# Configuration parameters: CountKeywordArgs.
-Metrics/ParameterLists:
-  Max: 10
-
-# Offense count: 15
-Metrics/PerceivedComplexity:
-  Max: 15
-
-# Offense count: 8
-Style/AccessorMethodName:
-  Enabled: false
-
-# Offense count: 23
-# Cop supports --auto-correct.
-Style/Alias:
-  Enabled: false
-
-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles, ProceduralMethods, FunctionalMethods, IgnoredMethods.
-Style/BlockDelimiters:
-  Enabled: false
-
-# Offense count: 7
-# Configuration parameters: EnforcedStyle, SupportedStyles.
-Style/ClassAndModuleChildren:
-  Enabled: false
-
-# Offense count: 15
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles.
-Style/ClassCheck:
-  Enabled: false
-
-# Offense count: 77
-Style/Documentation:
-  Enabled: false
-
-# Offense count: 1
-# Cop supports --auto-correct.
-Style/InfiniteLoop:
-  Enabled: false
-
-# Offense count: 1
-Style/ModuleFunction:
-  Enabled: false
-
-# Offense count: 1
-Style/MultilineBlockChain:
-  Enabled: false
-
-# Offense count: 3
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles, AllowInnerSlashes.
-Style/RegexpLiteral:
-  Enabled: false
-
-# Offense count: 2
-# Cop supports --auto-correct.
-# Configuration parameters: AllowAsExpressionSeparator.
-Style/Semicolon:
-  Enabled: false
-
-# Offense count: 79
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles.
-Style/SignalException:
-  Enabled: false
-
-# Offense count: 9
-# Cop supports --auto-correct.
-# Configuration parameters: MultiSpaceAllowedForOperators.
-Style/SpaceAroundOperators:
-  Enabled: false
-
-# Offense count: 30
-# Cop supports --auto-correct.
-Style/SpecialGlobalVars:
-  Enabled: false
-
-# Offense count: 22
-# Cop supports --auto-correct.
-# Configuration parameters: IgnoredMethods.
-Style/SymbolProc:
-  Enabled: false
-
-# Offense count: 151
-# Configuration parameters: EnforcedStyle, SupportedStyles.
-Style/VariableName:
-  Enabled: false
diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
new file mode 100644
index 00000000..4bff4fa4
--- /dev/null
+++ b/.rubocop_todo.yml
@@ -0,0 +1,164 @@
+# This configuration was generated by
+# `rubocop --auto-gen-config`
+# on 2020-02-08 14:58:51 +0000 using RuboCop version 0.79.0.
+# The point is for the user to remove these configuration records
+# one by one as the offenses are removed from the code base.
+# Note that changes in the inspected code, or installation of new
+# versions of RuboCop, may require this file to be generated again.
+
+# Offense count: 15
+# Configuration parameters: CountComments.
+Metrics/ClassLength:
+  Max: 580
+
+# Offense count: 26
+Metrics/CyclomaticComplexity:
+  Max: 14
+
+# Offense count: 120
+# Configuration parameters: CountComments, ExcludedMethods.
+Metrics/MethodLength:
+  Max: 30
+
+# Offense count: 2
+# Configuration parameters: CountKeywordArgs.
+Metrics/ParameterLists:
+  Max: 10
+
+# Offense count: 21
+Metrics/PerceivedComplexity:
+  Max: 15
+
+# Offense count: 9
+Naming/AccessorMethodName:
+  Exclude:
+    - 'lib/zip/entry.rb'
+    - 'lib/zip/filesystem.rb'
+    - 'lib/zip/input_stream.rb'
+    - 'lib/zip/streamable_stream.rb'
+    - 'test/file_permissions_test.rb'
+
+# Offense count: 18
+# Configuration parameters: MinNameLength, AllowNamesEndingInNumbers, AllowedNames, ForbiddenNames.
+Naming/BlockParameterName:
+  Exclude:
+    - 'lib/zip/file.rb'
+    - 'lib/zip/filesystem.rb'
+    - 'samples/zipfind.rb'
+    - 'test/central_directory_test.rb'
+    - 'test/file_extract_directory_test.rb'
+    - 'test/file_extract_test.rb'
+    - 'test/output_stream_test.rb'
+    - 'test/test_helper.rb'
+
+# Offense count: 140
+# Configuration parameters: MinNameLength, AllowNamesEndingInNumbers, AllowedNames, ForbiddenNames.
+# AllowedNames: io, id, to, by, on, in, at, ip, db, os
+Naming/MethodParameterName:
+  Enabled: false
+
+# Offense count: 721
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: snake_case, camelCase
+Naming/VariableName:
+  Enabled: false
+
+# Offense count: 7
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: inline, group
+Style/AccessModifierDeclarations:
+  Exclude:
+    - 'lib/zip/central_directory.rb'
+    - 'lib/zip/extra_field/zip64.rb'
+    - 'lib/zip/filesystem.rb'
+
+# Offense count: 7
+# Cop supports --auto-correct.
+# Configuration parameters: AutoCorrect, EnforcedStyle.
+# SupportedStyles: nested, compact
+Style/ClassAndModuleChildren:
+  Exclude:
+    - 'lib/zip/extra_field/generic.rb'
+    - 'lib/zip/extra_field/ntfs.rb'
+    - 'lib/zip/extra_field/old_unix.rb'
+    - 'lib/zip/extra_field/universal_time.rb'
+    - 'lib/zip/extra_field/unix.rb'
+    - 'lib/zip/extra_field/zip64.rb'
+    - 'lib/zip/extra_field/zip64_placeholder.rb'
+
+# Offense count: 26
+Style/Documentation:
+  Enabled: false
+
+# Offense count: 3
+# Configuration parameters: .
+# SupportedStyles: annotated, template, unannotated
+Style/FormatStringToken:
+  EnforcedStyle: unannotated
+
+# Offense count: 95
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: always, never
+Style/FrozenStringLiteralComment:
+  Enabled: false
+
+# Offense count: 17
+# Cop supports --auto-correct.
+Style/IfUnlessModifier:
+  Exclude:
+    - 'lib/zip/entry.rb'
+    - 'lib/zip/extra_field/generic.rb'
+    - 'lib/zip/file.rb'
+    - 'lib/zip/filesystem.rb'
+    - 'lib/zip/input_stream.rb'
+    - 'lib/zip/pass_thru_decompressor.rb'
+    - 'lib/zip/streamable_stream.rb'
+
+# Offense count: 1
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle, Autocorrect.
+# SupportedStyles: module_function, extend_self
+Style/ModuleFunction:
+  Exclude:
+    - 'lib/zip.rb'
+
+# Offense count: 56
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: literals, strict
+Style/MutableConstant:
+  Enabled: false
+
+# Offense count: 23
+# Cop supports --auto-correct.
+# Configuration parameters: AutoCorrect, EnforcedStyle, IgnoredMethods.
+# SupportedStyles: predicate, comparison
+Style/NumericPredicate:
+  Exclude:
+    - 'spec/**/*'
+    - 'lib/zip/entry.rb'
+    - 'lib/zip/extra_field/old_unix.rb'
+    - 'lib/zip/extra_field/universal_time.rb'
+    - 'lib/zip/extra_field/unix.rb'
+    - 'lib/zip/file.rb'
+    - 'lib/zip/filesystem.rb'
+    - 'lib/zip/input_stream.rb'
+    - 'lib/zip/ioextras.rb'
+    - 'lib/zip/ioextras/abstract_input_stream.rb'
+    - 'test/file_split_test.rb'
+    - 'test/test_helper.rb'
+
+# Offense count: 17
+# Cop supports --auto-correct.
+# Configuration parameters: ConvertCodeThatCanStartToReturnNil, AllowedMethods.
+# AllowedMethods: present?, blank?, presence, try, try!
+Style/SafeNavigation:
+  Exclude:
+    - 'lib/zip/entry.rb'
+    - 'lib/zip/input_stream.rb'
+    - 'lib/zip/output_stream.rb'
+    - 'test/file_extract_test.rb'
+    - 'test/filesystem/file_nonmutating_test.rb'
+    - 'test/filesystem/file_stat_test.rb'
+    - 'test/test_helper.rb'
diff --git a/Rakefile b/Rakefile
index 44a9b287..717c6b73 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,5 +1,6 @@
 require 'bundler/gem_tasks'
 require 'rake/testtask'
+require 'rubocop/rake_task'
 
 task default: :test
 
@@ -10,6 +11,8 @@ Rake::TestTask.new(:test) do |test|
   test.verbose = true
 end
 
+RuboCop::RakeTask.new
+
 # Rake::TestTask.new(:zip64_full_test) do |test|
 #  test.libs << File.join(File.dirname(__FILE__), 'lib')
 #  test.libs << File.join(File.dirname(__FILE__), 'test')
diff --git a/lib/zip.rb b/lib/zip.rb
index 5261fd77..8cf982a5 100644
--- a/lib/zip.rb
+++ b/lib/zip.rb
@@ -1,3 +1,4 @@
+require 'English'
 require 'delegate'
 require 'singleton'
 require 'tempfile'
diff --git a/lib/zip/central_directory.rb b/lib/zip/central_directory.rb
index 0b6874ef..496d668d 100644
--- a/lib/zip/central_directory.rb
+++ b/lib/zip/central_directory.rb
@@ -65,7 +65,7 @@ def write_64_e_o_c_d(io, offset, cdir_size) #:nodoc:
         @entry_set ? @entry_set.size : 0, # number of entries on this disk
         @entry_set ? @entry_set.size : 0, # number of entries total
         cdir_size, # size of central directory
-        offset, # offset of start of central directory in its disk
+        offset # offset of start of central directory in its disk
       ]
       io << tmp.pack('VQ<vvVVQ<Q<Q<Q<')
     end
@@ -141,6 +141,7 @@ def read_from_stream(io) #:nodoc:
     def get_e_o_c_d(buf) #:nodoc:
       sig_index = buf.rindex([END_OF_CDS].pack('V'))
       raise Error, 'Zip end of central directory signature not found' unless sig_index
+
       buf = buf.slice!((sig_index + 4)..(buf.bytesize))
 
       def buf.read(count)
@@ -166,8 +167,10 @@ def start_buf(io)
     def get_64_e_o_c_d(buf) #:nodoc:
       zip_64_start = buf.rindex([ZIP64_END_OF_CDS].pack('V'))
       raise Error, 'Zip64 end of central directory signature not found' unless zip_64_start
+
       zip_64_locator = buf.rindex([ZIP64_EOCD_LOCATOR].pack('V'))
       raise Error, 'Zip64 end of central directory signature locator not found' unless zip_64_locator
+
       buf = buf.slice!((zip_64_start + 4)..zip_64_locator)
 
       def buf.read(count)
@@ -191,13 +194,14 @@ def size
     def self.read_from_stream(io) #:nodoc:
       cdir = new
       cdir.read_from_stream(io)
-      return cdir
+      cdir
     rescue Error
-      return nil
+      nil
     end
 
     def ==(other) #:nodoc:
       return false unless other.kind_of?(CentralDirectory)
+
       @entry_set.entries.sort == other.entries.sort && comment == other.comment
     end
   end
diff --git a/lib/zip/constants.rb b/lib/zip/constants.rb
index 6feda25d..fe89847a 100644
--- a/lib/zip/constants.rb
+++ b/lib/zip/constants.rb
@@ -87,29 +87,29 @@ module Zip
   COMPRESSION_METHOD_AES = 99
 
   COMPRESSION_METHODS = {
-    COMPRESSION_METHOD_STORE => 'Store (no compression)',
-    COMPRESSION_METHOD_SHRINK => 'Shrink',
-    COMPRESSION_METHOD_REDUCE_1 => 'Reduce with compression factor 1',
-    COMPRESSION_METHOD_REDUCE_2 => 'Reduce with compression factor 2',
-    COMPRESSION_METHOD_REDUCE_3 => 'Reduce with compression factor 3',
-    COMPRESSION_METHOD_REDUCE_4 => 'Reduce with compression factor 4',
-    COMPRESSION_METHOD_IMPLODE => 'Implode',
+    COMPRESSION_METHOD_STORE       => 'Store (no compression)',
+    COMPRESSION_METHOD_SHRINK      => 'Shrink',
+    COMPRESSION_METHOD_REDUCE_1    => 'Reduce with compression factor 1',
+    COMPRESSION_METHOD_REDUCE_2    => 'Reduce with compression factor 2',
+    COMPRESSION_METHOD_REDUCE_3    => 'Reduce with compression factor 3',
+    COMPRESSION_METHOD_REDUCE_4    => 'Reduce with compression factor 4',
+    COMPRESSION_METHOD_IMPLODE     => 'Implode',
     # RESERVED = 7
-    COMPRESSION_METHOD_DEFLATE => 'Deflate',
-    COMPRESSION_METHOD_DEFLATE_64 => 'Deflate64(tm)',
+    COMPRESSION_METHOD_DEFLATE     => 'Deflate',
+    COMPRESSION_METHOD_DEFLATE_64  => 'Deflate64(tm)',
     COMPRESSION_METHOD_PKWARE_DCLI => 'PKWARE Data Compression Library Imploding (old IBM TERSE)',
     # RESERVED = 11
-    COMPRESSION_METHOD_BZIP2 => 'BZIP2',
+    COMPRESSION_METHOD_BZIP2       => 'BZIP2',
     # RESERVED = 13
-    COMPRESSION_METHOD_LZMA => 'LZMA',
+    COMPRESSION_METHOD_LZMA        => 'LZMA',
     # RESERVED = 15
-    COMPRESSION_METHOD_IBM_CMPSC => 'IBM z/OS CMPSC Compression',
+    COMPRESSION_METHOD_IBM_CMPSC   => 'IBM z/OS CMPSC Compression',
     # RESERVED = 17
-    COMPRESSION_METHOD_IBM_TERSE => 'IBM TERSE (new)',
-    COMPRESSION_METHOD_IBM_LZ77 => 'IBM LZ77 z Architecture (PFS)',
-    COMPRESSION_METHOD_JPEG => 'JPEG variant',
-    COMPRESSION_METHOD_WAVPACK => 'WavPack compressed data',
-    COMPRESSION_METHOD_PPMD => 'PPMd version I, Rev 1',
-    COMPRESSION_METHOD_AES => 'AES encryption',
+    COMPRESSION_METHOD_IBM_TERSE   => 'IBM TERSE (new)',
+    COMPRESSION_METHOD_IBM_LZ77    => 'IBM LZ77 z Architecture (PFS)',
+    COMPRESSION_METHOD_JPEG        => 'JPEG variant',
+    COMPRESSION_METHOD_WAVPACK     => 'WavPack compressed data',
+    COMPRESSION_METHOD_PPMD        => 'PPMd version I, Rev 1',
+    COMPRESSION_METHOD_AES         => 'AES encryption'
   }.freeze
 end
diff --git a/lib/zip/crypto/decrypted_io.rb b/lib/zip/crypto/decrypted_io.rb
index 1dab17c0..61a377da 100644
--- a/lib/zip/crypto/decrypted_io.rb
+++ b/lib/zip/crypto/decrypted_io.rb
@@ -8,10 +8,11 @@ def initialize(io, decrypter)
     end
 
     def read(length = nil, outbuf = +'')
-      return ((length.nil? || length.zero?) ? "" : nil) if eof
+      return (length.nil? || length.zero? ? '' : nil) if eof
 
       while length.nil? || (buffer.bytesize < length)
         break if input_finished?
+
         buffer << produce_input
       end
 
diff --git a/lib/zip/entry.rb b/lib/zip/entry.rb
index a24fb791..a67c6568 100644
--- a/lib/zip/entry.rb
+++ b/lib/zip/entry.rb
@@ -48,6 +48,7 @@ def set_default_vars_values
 
     def check_name(name)
       return unless name.start_with?('/')
+
       raise ::Zip::EntryNameError, "Illegal ZipEntry name '#{name}', name must not start with /"
     end
 
@@ -69,7 +70,7 @@ def initialize(*args)
       @time               = args[8] || ::Zip::DOSTime.now
 
       @ftype = name_is_directory? ? :directory : :file
-      @extra = ::Zip::ExtraField.new(@extra.to_s) unless @extra.is_a?(::Zip::ExtraField)
+      @extra = ::Zip::ExtraField.new(@extra.to_s) unless @extra.kind_of?(::Zip::ExtraField)
     end
 
     def encrypted?
@@ -99,11 +100,12 @@ def time=(value)
         @extra.create('UniversalTime')
       end
       (@extra['UniversalTime'] || @extra['NTFS']).mtime = value
-      @time                         = value
+      @time = value
     end
 
     def file_type_is?(type)
       raise InternalError, "current filetype is unknown: #{inspect}" unless @ftype
+
       @ftype == type
     end
 
@@ -124,6 +126,7 @@ def name_is_directory? #:nodoc:all
     def name_safe?
       cleanpath = Pathname.new(@name).cleanpath
       return false unless cleanpath.relative?
+
       root = ::File::SEPARATOR
       naive_expanded_path = ::File.join(root, cleanpath.to_s)
       ::File.absolute_path(cleanpath.to_s, root) == naive_expanded_path
@@ -153,6 +156,7 @@ def calculate_local_header_size #:nodoc:all
     # that we didn't change the header size (and thus clobber file data or something)
     def verify_local_header_size!
       return if @local_header_size.nil?
+
       new_size = calculate_local_header_size
       raise Error, "local header size changed (#{@local_header_size} -> #{new_size})" if @local_header_size != new_size
     end
@@ -178,12 +182,9 @@ def extract(dest_path = nil, &block)
       dest_path ||= @name
       block ||= proc { ::Zip.on_exists_proc }
 
-      if directory? || file? || symlink?
-        __send__("create_#{@ftype}", dest_path, &block)
-      else
-        raise "unknown file type #{inspect}"
-      end
+      raise "unknown file type #{inspect}" unless directory? || file? || symlink?
 
+      __send__("create_#{@ftype}", dest_path, &block)
       self
     end
 
@@ -193,15 +194,15 @@ def to_s
 
     class << self
       def read_zip_short(io) # :nodoc:
-        io.read(2).unpack('v')[0]
+        io.read(2).unpack1('v')
       end
 
       def read_zip_long(io) # :nodoc:
-        io.read(4).unpack('V')[0]
+        io.read(4).unpack1('V')
       end
 
       def read_zip_64_long(io) # :nodoc:
-        io.read(8).unpack('Q<')[0]
+        io.read(8).unpack1('Q<')
       end
 
       def read_c_dir_entry(io) #:nodoc:all
@@ -226,8 +227,6 @@ def read_local_entry(io)
       end
     end
 
-    public
-
     def unpack_local_entry(buf)
       @header_signature,
         @version,
@@ -257,6 +256,7 @@ def read_local_entry(io) #:nodoc:all
       unless @header_signature == ::Zip::LOCAL_ENTRY_SIGNATURE
         raise ::Zip::Error, "Zip local header magic not found at location '#{local_header_offset}'"
       end
+
       set_time(@last_mod_date, @last_mod_time)
 
       @name = io.read(@name_length)
@@ -269,13 +269,14 @@ def read_local_entry(io) #:nodoc:all
 
       if extra && extra.bytesize != @extra_length
         raise ::Zip::Error, 'Truncated local zip entry header'
+      end
+
+      if @extra.kind_of?(::Zip::ExtraField)
+        @extra.merge(extra) if extra
       else
-        if @extra.is_a?(::Zip::ExtraField)
-          @extra.merge(extra) if extra
-        else
-          @extra = ::Zip::ExtraField.new(extra)
-        end
+        @extra = ::Zip::ExtraField.new(extra)
       end
+
       parse_zip64_extra(true)
       @local_header_size = calculate_local_header_size
     end
@@ -362,21 +363,24 @@ def set_ftype_from_c_dir_entry
 
     def check_c_dir_entry_static_header_length(buf)
       return if buf.bytesize == ::Zip::CDIR_ENTRY_STATIC_HEADER_LENGTH
+
       raise Error, 'Premature end of file. Not enough data for zip cdir entry header'
     end
 
     def check_c_dir_entry_signature
       return if header_signature == ::Zip::CENTRAL_DIRECTORY_ENTRY_SIGNATURE
+
       raise Error, "Zip local header magic not found at location '#{local_header_offset}'"
     end
 
     def check_c_dir_entry_comment_size
       return if @comment && @comment.bytesize == @comment_length
+
       raise ::Zip::Error, 'Truncated cdir zip entry header'
     end
 
     def read_c_dir_extra_field(io)
-      if @extra.is_a?(::Zip::ExtraField)
+      if @extra.kind_of?(::Zip::ExtraField)
         @extra.merge(io.read(@extra_length))
       else
         @extra = ::Zip::ExtraField.new(io.read(@extra_length))
@@ -410,6 +414,7 @@ def file_stat(path) # :nodoc:
 
     def get_extra_attributes_from_path(path) # :nodoc:
       return if Zip::RUNNING_ON_WINDOWS
+
       stat        = file_stat(path)
       @unix_uid   = stat.uid
       @unix_gid   = stat.gid
@@ -496,6 +501,7 @@ def write_c_dir_entry(io) #:nodoc:all
 
     def ==(other)
       return false unless other.class == self.class
+
       # Compares contents of local entry and exposed fields
       keys_equal = %w[compression_method crc compressed_size size name extra filepath].all? do |k|
         other.__send__(k.to_sym) == __send__(k.to_sym)
@@ -619,15 +625,13 @@ def create_file(dest_path, _continue_on_exists_proc = proc { Zip.continue_on_exi
           while (buf = is.sysread(::Zip::Decompressor::CHUNK_SIZE, buf))
             os << buf
             bytes_written += buf.bytesize
-            if bytes_written > size && !warned
-              message = "entry '#{name}' should be #{size}B, but is larger when inflated."
-              if ::Zip.validate_entry_sizes
-                raise ::Zip::EntrySizeError, message
-              else
-                warn "WARNING: #{message}"
-                warned = true
-              end
-            end
+            next unless bytes_written > size && !warned
+
+            message = "entry '#{name}' should be #{size}B, but is larger when inflated."
+            raise ::Zip::EntrySizeError, message if ::Zip.validate_entry_sizes
+
+            warn "WARNING: #{message}"
+            warned = true
           end
         end
       end
@@ -637,6 +641,7 @@ def create_file(dest_path, _continue_on_exists_proc = proc { Zip.continue_on_exi
 
     def create_directory(dest_path)
       return if ::File.directory?(dest_path)
+
       if ::File.exist?(dest_path)
         if block_given? && yield(self, dest_path)
           ::FileUtils.rm_f dest_path
@@ -661,6 +666,7 @@ def create_symlink(dest_path)
     # (required when file sizes exceed 2**32, but can be used for all files)
     def parse_zip64_extra(for_local_header) #:nodoc:all
       return if @extra['Zip64'].nil?
+
       if for_local_header
         @size, @compressed_size = @extra['Zip64'].parse(@size, @compressed_size)
       else
@@ -675,6 +681,7 @@ def data_descriptor_size
     # create a zip64 extra information field if we need one
     def prep_zip64_extra(for_local_header) #:nodoc:all
       return unless ::Zip.write_zip64_support
+
       need_zip64 = @size >= 0xFFFFFFFF || @compressed_size >= 0xFFFFFFFF
       need_zip64 ||= @local_header_offset >= 0xFFFFFFFF unless for_local_header
       if need_zip64
diff --git a/lib/zip/entry_set.rb b/lib/zip/entry_set.rb
index 3272b2a4..9c503781 100644
--- a/lib/zip/entry_set.rb
+++ b/lib/zip/entry_set.rb
@@ -50,6 +50,7 @@ def dup
 
     def ==(other)
       return false unless other.kind_of?(EntrySet)
+
       @entry_set.values == other.entry_set.values
     end
 
@@ -60,6 +61,7 @@ def parent(entry)
     def glob(pattern, flags = ::File::FNM_PATHNAME | ::File::FNM_DOTMATCH | ::File::FNM_EXTGLOB)
       entries.map do |entry|
         next nil unless ::File.fnmatch(pattern, entry.name.chomp('/'), flags)
+
         yield(entry) if block_given?
         entry
       end.compact
diff --git a/lib/zip/extra_field.rb b/lib/zip/extra_field.rb
index 0dcf0d5e..e4b00b66 100644
--- a/lib/zip/extra_field.rb
+++ b/lib/zip/extra_field.rb
@@ -36,10 +36,11 @@ class << s
 
     def merge(binstr)
       return if binstr.empty?
+
       i = 0
       while i < binstr.bytesize
         id  = binstr[i, 2]
-        len = binstr[i + 2, 2].to_s.unpack('v').first
+        len = binstr[i + 2, 2].to_s.unpack1('v')
         if id && ID_MAP.member?(id)
           extra_field_type_exist(binstr, id, len, i)
         elsif id
@@ -54,6 +55,7 @@ def create(name)
       unless (field_class = ID_MAP.values.find { |k| k.name == name })
         raise Error, "Unknown extra field '#{name}'"
       end
+
       self[name] = field_class.new
     end
 
diff --git a/lib/zip/extra_field/generic.rb b/lib/zip/extra_field/generic.rb
index d61137fe..5eb702d6 100644
--- a/lib/zip/extra_field/generic.rb
+++ b/lib/zip/extra_field/generic.rb
@@ -1,9 +1,9 @@
 module Zip
   class ExtraField::Generic
     def self.register_map
-      if const_defined?(:HEADER_ID)
-        ::Zip::ExtraField::ID_MAP[const_get(:HEADER_ID)] = self
-      end
+      return unless const_defined?(:HEADER_ID)
+
+      ::Zip::ExtraField::ID_MAP[const_get(:HEADER_ID)] = self
     end
 
     def self.name
@@ -12,18 +12,19 @@ def self.name
 
     # return field [size, content] or false
     def initial_parse(binstr)
-      if !binstr
-        # If nil, start with empty.
-        return false
-      elsif binstr[0, 2] != self.class.const_get(:HEADER_ID)
+      return false unless binstr
+
+      if binstr[0, 2] != self.class.const_get(:HEADER_ID)
         warn 'WARNING: weird extra field header ID. Skip parsing it.'
         return false
       end
-      [binstr[2, 2].unpack('v')[0], binstr[4..-1]]
+
+      [binstr[2, 2].unpack1('v'), binstr[4..-1]]
     end
 
     def ==(other)
       return false if self.class != other.class
+
       each do |k, v|
         return false if v != other[k]
       end
diff --git a/lib/zip/extra_field/ntfs.rb b/lib/zip/extra_field/ntfs.rb
index 687704d8..f4f11b2d 100644
--- a/lib/zip/extra_field/ntfs.rb
+++ b/lib/zip/extra_field/ntfs.rb
@@ -19,6 +19,7 @@ def initialize(binstr = nil)
 
     def merge(binstr)
       return if binstr.empty?
+
       size, content = initial_parse(binstr)
       (size && content) || return
 
@@ -27,6 +28,7 @@ def merge(binstr)
 
       tag1 = tags[1]
       return unless tag1
+
       ntfs_mtime, ntfs_atime, ntfs_ctime = tag1.unpack('Q<Q<Q<')
       ntfs_mtime && @mtime ||= from_ntfs_time(ntfs_mtime)
       ntfs_atime && @atime ||= from_ntfs_time(ntfs_atime)
@@ -65,12 +67,14 @@ def pack_for_c_dir
 
     def parse_tags(content)
       return {} if content.nil?
+
       tags = {}
       i = 0
       while i < content.bytesize
         tag, size = content[i, 4].unpack('vv')
         i += 4
         break unless tag && size
+
         value = content[i, size]
         i += size
         tags[tag] = value
diff --git a/lib/zip/extra_field/old_unix.rb b/lib/zip/extra_field/old_unix.rb
index 5a97c616..a9755b09 100644
--- a/lib/zip/extra_field/old_unix.rb
+++ b/lib/zip/extra_field/old_unix.rb
@@ -16,9 +16,11 @@ def initialize(binstr = nil)
 
     def merge(binstr)
       return if binstr.empty?
+
       size, content = initial_parse(binstr)
       # size: 0 for central directory. 4 for local header
       return if !size || size == 0
+
       atime, mtime, uid, gid = content.unpack('VVvv')
       @uid ||= uid
       @gid ||= gid
diff --git a/lib/zip/extra_field/universal_time.rb b/lib/zip/extra_field/universal_time.rb
index 5c3b1c16..424c281d 100644
--- a/lib/zip/extra_field/universal_time.rb
+++ b/lib/zip/extra_field/universal_time.rb
@@ -44,10 +44,13 @@ def merge(binstr)
 
       # Parse the timestamps, in order, based on which flags are set.
       return if times[0].nil?
+
       @mtime ||= ::Zip::DOSTime.at(times.shift) unless @flag & MTIME_MASK == 0
       return if times[0].nil?
+
       @atime ||= ::Zip::DOSTime.at(times.shift) unless @flag & ATIME_MASK == 0
       return if times[0].nil?
+
       @ctime ||= ::Zip::DOSTime.at(times.shift) unless @flag & CTIME_MASK == 0
     end
 
diff --git a/lib/zip/extra_field/unix.rb b/lib/zip/extra_field/unix.rb
index a3e63963..1bb70391 100644
--- a/lib/zip/extra_field/unix.rb
+++ b/lib/zip/extra_field/unix.rb
@@ -14,9 +14,11 @@ def initialize(binstr = nil)
 
     def merge(binstr)
       return if binstr.empty?
+
       size, content = initial_parse(binstr)
       # size: 0 for central directory. 4 for local header
       return if !size || size == 0
+
       uid, gid = content.unpack('vv')
       @uid ||= uid
       @gid ||= gid
diff --git a/lib/zip/extra_field/zip64.rb b/lib/zip/extra_field/zip64.rb
index 962038d8..9826c6cf 100644
--- a/lib/zip/extra_field/zip64.rb
+++ b/lib/zip/extra_field/zip64.rb
@@ -9,7 +9,7 @@ def initialize(binstr = nil)
       # unparsed binary; we don't actually know what this contains
       # without looking for FFs in the associated file header
       # call parse after initializing with a binary string
-      @content = nil
+      @content                = nil
       @original_size          = nil
       @compressed_size        = nil
       @relative_header_offset = nil
@@ -26,6 +26,7 @@ def ==(other)
 
     def merge(binstr)
       return if binstr.empty?
+
       _, @content = initial_parse(binstr)
     end
 
@@ -45,13 +46,14 @@ def parse(original_size, compressed_size, relative_header_offset = nil, disk_sta
     end
 
     def extract(size, format)
-      @content.slice!(0, size).unpack(format)[0]
+      @content.slice!(0, size).unpack1(format)
     end
     private :extract
 
     def pack_for_local
       # local header entries must contain original size and compressed size; other fields do not apply
       return '' unless @original_size && @compressed_size
+
       [@original_size, @compressed_size].pack('Q<Q<')
     end
 
diff --git a/lib/zip/file.rb b/lib/zip/file.rb
index 45017822..c768d07d 100644
--- a/lib/zip/file.rb
+++ b/lib/zip/file.rb
@@ -75,7 +75,7 @@ class File < CentralDirectory
     # a new archive if it doesn't exist already.
     def initialize(path_or_io, create = false, buffer = false, options = {})
       super()
-      options = DEFAULT_OPTIONS.merge(options)
+      options  = DEFAULT_OPTIONS.merge(options)
       @name    = path_or_io.respond_to?(:path) ? path_or_io.path : path_or_io
       @comment = ''
       @create  = create ? true : false # allow any truthy value to mean true
@@ -120,6 +120,7 @@ class << self
       def open(file_name, create = false, options = {})
         zf = ::Zip::File.new(file_name, create, false, options)
         return zf unless block_given?
+
         begin
           yield zf
         ensure
@@ -140,17 +141,18 @@ def add_buffer
       # (This can be used to extract data from a
       # downloaded zip archive without first saving it to disk.)
       def open_buffer(io, options = {})
-        unless IO_METHODS.map { |method| io.respond_to?(method) }.all? || io.is_a?(String)
+        unless IO_METHODS.map { |method| io.respond_to?(method) }.all? || io.kind_of?(String)
           raise "Zip::File.open_buffer expects a String or IO-like argument (responds to #{IO_METHODS.join(', ')}). Found: #{io.class}"
         end
 
-        io = ::StringIO.new(io) if io.is_a?(::String)
+        io = ::StringIO.new(io) if io.kind_of?(::String)
 
         # https://github.com/rubyzip/rubyzip/issues/119
         io.binmode if io.respond_to?(:binmode)
 
         zf = ::Zip::File.new(io, true, true, options)
         return zf unless block_given?
+
         yield zf
 
         begin
@@ -167,7 +169,7 @@ def open_buffer(io, options = {})
       # local entry headers (which contain the same information as the
       # central directory).
       def foreach(aZipFileName, &block)
-        open(aZipFileName) do |zipFile|
+        ::Zip::File.open(aZipFileName) do |zipFile|
           zipFile.each(&block)
         end
       end
@@ -229,12 +231,14 @@ def save_splited_part(zip_file, partial_zip_file_name, zip_file_size, szip_file_
       def split(zip_file_name, segment_size = MAX_SEGMENT_SIZE, delete_zip_file = true, partial_zip_file_name = nil)
         raise Error, "File #{zip_file_name} not found" unless ::File.exist?(zip_file_name)
         raise Errno::ENOENT, zip_file_name unless ::File.readable?(zip_file_name)
+
         zip_file_size = ::File.size(zip_file_name)
         segment_size  = get_segment_size_for_split(segment_size)
         return if zip_file_size <= segment_size
+
         segment_count = get_segment_count_for_split(zip_file_size, segment_size)
         # Checking for correct zip structure
-        open(zip_file_name) {}
+        ::Zip::File.open(zip_file_name) {}
         partial_zip_file_name = get_partial_zip_file_name(zip_file_name, partial_zip_file_name)
         szip_file_index       = 0
         ::File.open(zip_file_name, 'rb') do |zip_file|
@@ -260,7 +264,11 @@ def get_input_stream(entry, &aProc)
     # specified. If a block is passed the stream object is passed to the block and
     # the stream is automatically closed afterwards just as with ruby's builtin
     # File.open method.
-    def get_output_stream(entry, permission_int = nil, comment = nil, extra = nil, compressed_size = nil, crc = nil, compression_method = nil, size = nil, time = nil, &aProc)
+    def get_output_stream(entry, permission_int = nil, comment = nil,
+                          extra = nil, compressed_size = nil, crc = nil,
+                          compression_method = nil, size = nil, time = nil,
+                          &aProc)
+
       new_entry =
         if entry.kind_of?(Entry)
           entry
@@ -284,7 +292,7 @@ def to_s
 
     # Returns a string containing the contents of the specified entry
     def read(entry)
-      get_input_stream(entry) { |is| is.read }
+      get_input_stream(entry, &:read)
     end
 
     # Convenience method for adding the contents of a file to the archive
@@ -336,7 +344,8 @@ def extract(entry, dest_path, &block)
     # Commits changes that has been made since the previous commit to
     # the zip archive.
     def commit
-      return if name.is_a?(StringIO) || !commit_required?
+      return if name.kind_of?(StringIO) || !commit_required?
+
       on_success_replace do |tmp_file|
         ::Zip::OutputStream.open(tmp_file) do |zos|
           @entry_set.each do |e|
@@ -402,6 +411,7 @@ def get_entry(entry)
     # Creates a directory
     def mkdir(entryName, permissionInt = 0o755)
       raise Errno::EEXIST, "File exists - #{entryName}" if find_entry(entryName)
+
       entryName = entryName.dup.to_s
       entryName << '/' unless entryName.end_with?('/')
       @entry_set << ::Zip::StreamableDirectory.new(@name, entryName, nil, permissionInt)
@@ -424,6 +434,7 @@ def directory?(newEntry, srcPath)
     def check_entry_exists(entryName, continue_on_exists_proc, procedureName)
       continue_on_exists_proc ||= proc { Zip.continue_on_exists_proc }
       return unless @entry_set.include?(entryName)
+
       if continue_on_exists_proc.call
         remove get_entry(entryName)
       else
diff --git a/lib/zip/filesystem.rb b/lib/zip/filesystem.rb
index 81ad1a18..4f3e9954 100644
--- a/lib/zip/filesystem.rb
+++ b/lib/zip/filesystem.rb
@@ -35,9 +35,9 @@ module Zip
 
   module FileSystem
     def initialize # :nodoc:
-      mappedZip = ZipFileNameMapper.new(self)
-      @zipFsDir  = ZipFsDir.new(mappedZip)
-      @zipFsFile = ZipFsFile.new(mappedZip)
+      mappedZip      = ZipFileNameMapper.new(self)
+      @zipFsDir      = ZipFsDir.new(mappedZip)
+      @zipFsFile     = ZipFsFile.new(mappedZip)
       @zipFsDir.file = @zipFsFile
       @zipFsFile.dir = @zipFsDir
     end
@@ -70,11 +70,11 @@ class ZipFsStat
         class << self
           def delegate_to_fs_file(*methods)
             methods.each do |method|
-              class_eval <<-end_eval, __FILE__, __LINE__ + 1
+              class_eval <<-END_EVAL, __FILE__, __LINE__ + 1
                 def #{method}                      # def file?
                   @zipFsFile.#{method}(@entryName) #   @zipFsFile.file?(@entryName)
                 end                                # end
-              end_eval
+              END_EVAL
             end
           end
         end
@@ -176,6 +176,7 @@ def get_entry(fileName)
         unless exists?(fileName)
           raise Errno::ENOENT, "No such file or directory - #{fileName}"
         end
+
         @mappedZip.find_entry(fileName)
       end
       private :get_entry
@@ -250,7 +251,7 @@ def open(fileName, openMode = 'r', permissionInt = 0o644, &block)
       end
 
       def new(fileName, openMode = 'r')
-        open(fileName, openMode)
+        self.open(fileName, openMode)
       end
 
       def size(fileName)
@@ -382,13 +383,14 @@ def pipe
 
       def stat(fileName)
         raise Errno::ENOENT, fileName unless exists?(fileName)
+
         ZipFsStat.new(self, fileName)
       end
 
       alias lstat stat
 
       def readlines(fileName)
-        open(fileName) { |is| is.readlines }
+        self.open(fileName, &:readlines)
       end
 
       def read(fileName)
@@ -399,8 +401,8 @@ def popen(*args, &aProc)
         ::File.popen(*args, &aProc)
       end
 
-      def foreach(fileName, aSep = $/, &aProc)
-        open(fileName) { |is| is.each_line(aSep, &aProc) }
+      def foreach(fileName, aSep = $INPUT_RECORD_SEPARATOR, &aProc)
+        self.open(fileName) { |is| is.each_line(aSep, &aProc) }
       end
 
       def delete(*args)
@@ -408,6 +410,7 @@ def delete(*args)
           if directory?(fileName)
             raise Errno::EISDIR, "Is a directory - \"#{fileName}\""
           end
+
           @mappedZip.remove(fileName)
         end
       end
@@ -462,6 +465,7 @@ def chdir(aDirectoryName)
         unless @file.stat(aDirectoryName).directory?
           raise Errno::EINVAL, "Invalid argument - #{aDirectoryName}"
         end
+
         @mappedZip.pwd = @file.expand_path(aDirectoryName)
       end
 
@@ -479,6 +483,7 @@ def foreach(aDirectoryName)
         unless @file.stat(aDirectoryName).directory?
           raise Errno::ENOTDIR, aDirectoryName
         end
+
         path = @file.expand_path(aDirectoryName)
         path << '/' unless path.end_with?('/')
         path = Regexp.escape(path)
@@ -493,6 +498,7 @@ def delete(entryName)
         unless @file.stat(entryName).directory?
           raise Errno::EINVAL, "Invalid argument - #{entryName}"
         end
+
         @mappedZip.remove(entryName)
       end
       alias rmdir delete
@@ -521,26 +527,31 @@ def close
 
       def each(&aProc)
         raise IOError, 'closed directory' if @fileNames.nil?
+
         @fileNames.each(&aProc)
       end
 
       def read
         raise IOError, 'closed directory' if @fileNames.nil?
+
         @fileNames[(@index += 1) - 1]
       end
 
       def rewind
         raise IOError, 'closed directory' if @fileNames.nil?
+
         @index = 0
       end
 
       def seek(anIntegerPosition)
         raise IOError, 'closed directory' if @fileNames.nil?
+
         @index = anIntegerPosition
       end
 
       def tell
         raise IOError, 'closed directory' if @fileNames.nil?
+
         @index
       end
     end
diff --git a/lib/zip/inflater.rb b/lib/zip/inflater.rb
index c18f245c..530f98aa 100644
--- a/lib/zip/inflater.rb
+++ b/lib/zip/inflater.rb
@@ -8,10 +8,11 @@ def initialize(*args)
     end
 
     def read(length = nil, outbuf = '')
-      return ((length.nil? || length.zero?) ? "" : nil) if eof
+      return (length.nil? || length.zero? ? '' : nil) if eof
 
       while length.nil? || (@buffer.bytesize < length)
         break if input_finished?
+
         @buffer << produce_input
       end
 
@@ -22,7 +23,7 @@ def eof
       @buffer.empty? && input_finished?
     end
 
-    alias_method :eof?, :eof
+    alias eof? eof
 
     private
 
@@ -32,6 +33,7 @@ def produce_input
         @zlib_inflater.inflate(input_stream.read(Decompressor::CHUNK_SIZE))
       rescue Zlib::BufError
         raise if retried >= 5 # how many times should we retry?
+
         retried += 1
         retry
       end
diff --git a/lib/zip/input_stream.rb b/lib/zip/input_stream.rb
index b4c502f5..f942d190 100644
--- a/lib/zip/input_stream.rb
+++ b/lib/zip/input_stream.rb
@@ -51,7 +51,7 @@ class InputStream
     # @param offset [Integer] offset in the IO/StringIO
     def initialize(context, offset = 0, decrypter = nil)
       super()
-      @archive_io = get_io(context, offset)
+      @archive_io    = get_io(context, offset)
       @decompressor  = ::Zip::NullDecompressor
       @decrypter     = decrypter || ::Zip::NullDecrypter.new
       @current_entry = nil
@@ -73,6 +73,7 @@ def get_next_entry
     # Rewinds the stream to the beginning of the current entry
     def rewind
       return if @current_entry.nil?
+
       @lineno = 0
       @pos    = 0
       @archive_io.seek(@current_entry.local_header_offset, IO::SEEK_SET)
@@ -91,6 +92,7 @@ class << self
       def open(filename_or_io, offset = 0, decrypter = nil)
         zio = new(filename_or_io, offset, decrypter)
         return zio unless block_given?
+
         begin
           yield zio
         ensure
@@ -100,7 +102,7 @@ def open(filename_or_io, offset = 0, decrypter = nil)
 
       def open_buffer(filename_or_io, offset = 0)
         warn 'open_buffer is deprecated!!! Use open instead!'
-        open(filename_or_io, offset)
+        ::Zip::InputStream.open(filename_or_io, offset)
       end
     end
 
@@ -120,9 +122,10 @@ def get_io(io_or_file, offset = 0)
 
     def open_entry
       @current_entry = ::Zip::Entry.read_local_entry(@archive_io)
-      if @current_entry && @current_entry.encrypted? && @decrypter.is_a?(NullEncrypter)
+      if @current_entry && @current_entry.encrypted? && @decrypter.kind_of?(NullEncrypter)
         raise Error, 'password required to decode zip file'
       end
+
       if @current_entry && @current_entry.incomplete? && @current_entry.crc == 0 \
         && @current_entry.compressed_size == 0 \
         && @current_entry.size == 0 && !@complete_entry
diff --git a/lib/zip/ioextras.rb b/lib/zip/ioextras.rb
index 2412480b..63774d33 100644
--- a/lib/zip/ioextras.rb
+++ b/lib/zip/ioextras.rb
@@ -25,7 +25,7 @@ def kind_of?(object)
         object == IO || super
       end
     end
-  end # IOExtras namespace module
+  end
 end
 
 require 'zip/ioextras/abstract_input_stream'
diff --git a/lib/zip/ioextras/abstract_input_stream.rb b/lib/zip/ioextras/abstract_input_stream.rb
index 58678a3f..8392d240 100644
--- a/lib/zip/ioextras/abstract_input_stream.rb
+++ b/lib/zip/ioextras/abstract_input_stream.rb
@@ -35,6 +35,7 @@ def read(number_of_bytes = nil, buf = '')
 
         if tbuf.nil? || tbuf.empty?
           return nil if number_of_bytes
+
           return ''
         end
 
@@ -48,13 +49,13 @@ def read(number_of_bytes = nil, buf = '')
         buf
       end
 
-      def readlines(a_sep_string = $/)
+      def readlines(a_sep_string = $INPUT_RECORD_SEPARATOR)
         ret_val = []
         each_line(a_sep_string) { |line| ret_val << line }
         ret_val
       end
 
-      def gets(a_sep_string = $/, number_of_bytes = nil)
+      def gets(a_sep_string = $INPUT_RECORD_SEPARATOR, number_of_bytes = nil)
         @lineno = @lineno.next
 
         if number_of_bytes.respond_to?(:to_int)
@@ -62,20 +63,22 @@ def gets(a_sep_string = $/, number_of_bytes = nil)
           a_sep_string = a_sep_string.to_str if a_sep_string
         elsif a_sep_string.respond_to?(:to_int)
           number_of_bytes = a_sep_string.to_int
-          a_sep_string    = $/
+          a_sep_string    = $INPUT_RECORD_SEPARATOR
         else
           number_of_bytes = nil
           a_sep_string = a_sep_string.to_str if a_sep_string
         end
 
         return read(number_of_bytes) if a_sep_string.nil?
-        a_sep_string = "#{$/}#{$/}" if a_sep_string.empty?
+
+        a_sep_string = "#{$INPUT_RECORD_SEPARATOR}#{$INPUT_RECORD_SEPARATOR}" if a_sep_string.empty?
 
         buffer_index = 0
         over_limit   = (number_of_bytes && @output_buffer.bytesize >= number_of_bytes)
         while (match_index = @output_buffer.index(a_sep_string, buffer_index)).nil? && !over_limit
           buffer_index = [buffer_index, @output_buffer.bytesize - a_sep_string.bytesize].max
           return @output_buffer.empty? ? nil : flush if input_finished?
+
           @output_buffer << produce_input
           over_limit = (number_of_bytes && @output_buffer.bytesize >= number_of_bytes)
         end
@@ -94,24 +97,26 @@ def flush
         ret_val
       end
 
-      def readline(a_sep_string = $/)
+      def readline(a_sep_string = $INPUT_RECORD_SEPARATOR)
         ret_val = gets(a_sep_string)
         raise EOFError unless ret_val
+
         ret_val
       end
 
-      def each_line(a_sep_string = $/)
-        yield readline(a_sep_string) while true
+      def each_line(a_sep_string = $INPUT_RECORD_SEPARATOR)
+        loop { yield readline(a_sep_string) }
       rescue EOFError
+        # We just need to catch this; we don't need to handle it.
       end
 
-      alias_method :each, :each_line
+      alias each each_line
 
       def eof
         @output_buffer.empty? && input_finished?
       end
 
-      alias_method :eof?, :eof
+      alias eof? eof
     end
   end
 end
diff --git a/lib/zip/ioextras/abstract_output_stream.rb b/lib/zip/ioextras/abstract_output_stream.rb
index 69d0cc7c..b94c9d49 100644
--- a/lib/zip/ioextras/abstract_output_stream.rb
+++ b/lib/zip/ioextras/abstract_output_stream.rb
@@ -11,7 +11,7 @@ def write(data)
       end
 
       def print(*params)
-        self << params.join($,) << $\.to_s
+        self << params.join($OUTPUT_FIELD_SEPARATOR) << $OUTPUT_RECORD_SEPARATOR.to_s
       end
 
       def printf(a_format_string, *params)
diff --git a/lib/zip/output_stream.rb b/lib/zip/output_stream.rb
index d9bbc4df..2f628931 100644
--- a/lib/zip/output_stream.rb
+++ b/lib/zip/output_stream.rb
@@ -49,6 +49,7 @@ def initialize(file_name, stream = false, encrypter = nil)
     class << self
       def open(file_name, encrypter = nil)
         return new(file_name) unless block_given?
+
         zos = new(file_name, false, encrypter)
         yield zos
       ensure
@@ -66,6 +67,7 @@ def write_buffer(io = ::StringIO.new(''), encrypter = nil)
     # Closes the stream and writes the central directory to the zip file
     def close
       return if @closed
+
       finalize_current_entry
       update_local_headers
       write_central_directory
@@ -76,6 +78,7 @@ def close
     # Closes the stream and writes the central directory to the zip file
     def close_buffer
       return @output_stream if @closed
+
       finalize_current_entry
       update_local_headers
       write_central_directory
@@ -87,6 +90,7 @@ def close_buffer
     # +entry+ can be a ZipEntry object or a string.
     def put_next_entry(entry_name, comment = nil, extra = nil, compression_method = Entry::DEFLATED, level = Zip.default_compression)
       raise Error, 'zip stream is closed' if @closed
+
       new_entry = if entry_name.kind_of?(Entry)
                     entry_name
                   else
@@ -94,7 +98,7 @@ def put_next_entry(entry_name, comment = nil, extra = nil, compression_method =
                   end
       new_entry.comment = comment unless comment.nil?
       unless extra.nil?
-        new_entry.extra = extra.is_a?(ExtraField) ? extra : ExtraField.new(extra.to_s)
+        new_entry.extra = extra.kind_of?(ExtraField) ? extra : ExtraField.new(extra.to_s)
       end
       new_entry.compression_method = compression_method unless compression_method.nil?
       init_next_entry(new_entry, level)
@@ -104,7 +108,8 @@ def put_next_entry(entry_name, comment = nil, extra = nil, compression_method =
     def copy_raw_entry(entry)
       entry = entry.dup
       raise Error, 'zip stream is closed' if @closed
-      raise Error, 'entry is not a ZipEntry' unless entry.is_a?(Entry)
+      raise Error, 'entry is not a ZipEntry' unless entry.kind_of?(Entry)
+
       finalize_current_entry
       @entry_set << entry
       src_pos = entry.local_header_offset
@@ -123,8 +128,11 @@ def copy_raw_entry(entry)
 
     def finalize_current_entry
       return unless @current_entry
+
       finish
-      @current_entry.compressed_size = @output_stream.tell - @current_entry.local_header_offset - @current_entry.calculate_local_header_size
+      @current_entry.compressed_size = @output_stream.tell - \
+                                       @current_entry.local_header_offset - \
+                                       @current_entry.calculate_local_header_size
       @current_entry.size = @compressor.size
       @current_entry.crc = @compressor.crc
       @output_stream << @encrypter.data_descriptor(@current_entry.crc, @current_entry.compressed_size, @current_entry.size)
@@ -144,9 +152,9 @@ def init_next_entry(entry, level = Zip.default_compression)
 
     def get_compressor(entry, level)
       case entry.compression_method
-      when Entry::DEFLATED then
+      when Entry::DEFLATED
         ::Zip::Deflater.new(@output_stream, level, @encrypter)
-      when Entry::STORED then
+      when Entry::STORED
         ::Zip::PassThruCompressor.new(@output_stream)
       else
         raise ::Zip::CompressionMethodError,
diff --git a/lib/zip/pass_thru_decompressor.rb b/lib/zip/pass_thru_decompressor.rb
index ac21b61e..e638540e 100644
--- a/lib/zip/pass_thru_decompressor.rb
+++ b/lib/zip/pass_thru_decompressor.rb
@@ -6,7 +6,7 @@ def initialize(*args)
     end
 
     def read(length = nil, outbuf = '')
-      return ((length.nil? || length.zero?) ? "" : nil) if eof
+      return (length.nil? || length.zero? ? '' : nil) if eof
 
       if length.nil? || (@read_so_far + length) > decompressed_size
         length = decompressed_size - @read_so_far
@@ -20,7 +20,7 @@ def eof
       @read_so_far >= decompressed_size
     end
 
-    alias_method :eof?, :eof
+    alias eof? eof
   end
 
   ::Zip::Decompressor.register(::Zip::COMPRESSION_METHOD_STORE, ::Zip::PassThruDecompressor)
diff --git a/lib/zip/streamable_stream.rb b/lib/zip/streamable_stream.rb
index 642ddae2..1a726b99 100644
--- a/lib/zip/streamable_stream.rb
+++ b/lib/zip/streamable_stream.rb
@@ -1,5 +1,5 @@
 module Zip
-  class StreamableStream < DelegateClass(Entry) # nodoc:all
+  class StreamableStream < DelegateClass(Entry) # :nodoc:all
     def initialize(entry)
       super(entry)
       @temp_file = Tempfile.new(::File.basename(name))
@@ -22,6 +22,7 @@ def get_input_stream
       unless @temp_file.closed?
         raise StandardError, "cannot open entry for reading while its open for writing - #{name}"
       end
+
       @temp_file.open # reopens tempfile from top
       @temp_file.binmode
       if block_given?
diff --git a/rubyzip.gemspec b/rubyzip.gemspec
index f8c59a18..1707ef5d 100644
--- a/rubyzip.gemspec
+++ b/rubyzip.gemspec
@@ -1,6 +1,4 @@
-#-*- encoding: utf-8 -*-
-
-lib = File.expand_path('../lib', __FILE__)
+lib = File.expand_path('lib', __dir__)
 $LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
 require 'zip/version'
 
@@ -23,9 +21,9 @@ Gem::Specification.new do |s|
     'wiki_uri'          => 'https://github.com/rubyzip/rubyzip/wiki'
   }
   s.required_ruby_version = '>= 2.4'
-  s.add_development_dependency 'rake', '~> 10.3'
-  s.add_development_dependency 'pry', '~> 0.10'
-  s.add_development_dependency 'minitest', '~> 5.4'
   s.add_development_dependency 'coveralls', '~> 0.7'
-  s.add_development_dependency 'rubocop', '~> 0.49.1'
+  s.add_development_dependency 'minitest', '~> 5.4'
+  s.add_development_dependency 'pry', '~> 0.10'
+  s.add_development_dependency 'rake', '~> 10.3'
+  s.add_development_dependency 'rubocop', '~> 0.79'
 end
diff --git a/samples/example.rb b/samples/example.rb
index 224d4f1c..345e7e19 100755
--- a/samples/example.rb
+++ b/samples/example.rb
@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-$: << '../lib'
+$LOAD_PATH << '../lib'
 system('zip example.zip example.rb gtk_ruby_zip.rb')
 
 require 'zip'
@@ -71,7 +71,7 @@
 
 # Track splitting an archive
 Zip::File.split('large_zip_file.zip', 1_048_576, true, 'part_zip_file') do |part_count, part_index, chunk_bytes, segment_bytes|
-  puts "#{part_index} of #{part_count} part splitting: #{(chunk_bytes.to_f / segment_bytes.to_f * 100).to_i}%"
+  puts "#{part_index} of #{part_count} part splitting: #{(chunk_bytes.to_f / segment_bytes * 100).to_i}%"
 end
 
 # For other examples, look at zip.rb and ziptest.rb
diff --git a/samples/example_filesystem.rb b/samples/example_filesystem.rb
index f253a5e5..0d93ab6b 100755
--- a/samples/example_filesystem.rb
+++ b/samples/example_filesystem.rb
@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-$: << '../lib'
+$LOAD_PATH << '../lib'
 
 require 'zip/filesystem'
 
diff --git a/samples/gtk_ruby_zip.rb b/samples/gtk_ruby_zip.rb
index 62f005a5..4ce1cae0 100755
--- a/samples/gtk_ruby_zip.rb
+++ b/samples/gtk_ruby_zip.rb
@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-$: << '../lib'
+$LOAD_PATH << '../lib'
 
 $VERBOSE = true
 
diff --git a/samples/qtzip.rb b/samples/qtzip.rb
index 1d450a78..f76f57a7 100755
--- a/samples/qtzip.rb
+++ b/samples/qtzip.rb
@@ -2,7 +2,7 @@
 
 $VERBOSE = true
 
-$: << '../lib'
+$LOAD_PATH << '../lib'
 
 require 'Qt'
 system('rbuic -o zipdialogui.rb zipdialogui.ui')
@@ -80,7 +80,7 @@ def extract_files
 end
 
 unless ARGV[0]
-  puts "usage: #{$0} zipname"
+  puts "usage: #{$PROGRAM_NAME} zipname"
   exit
 end
 
diff --git a/samples/write_simple.rb b/samples/write_simple.rb
index be2a9704..8bb31bb3 100755
--- a/samples/write_simple.rb
+++ b/samples/write_simple.rb
@@ -1,12 +1,10 @@
 #!/usr/bin/env ruby
 
-$: << '../lib'
+$LOAD_PATH << '../lib'
 
 require 'zip'
 
-include Zip
-
-OutputStream.open('simple.zip') do |zos|
+::Zip::OutputStream.open('simple.zip') do |zos|
   zos.put_next_entry 'entry.txt'
   zos.puts 'Hello world'
 end
diff --git a/samples/zipfind.rb b/samples/zipfind.rb
index 400e0a69..a88bc42d 100755
--- a/samples/zipfind.rb
+++ b/samples/zipfind.rb
@@ -2,7 +2,7 @@
 
 $VERBOSE = true
 
-$: << '../lib'
+$LOAD_PATH << '../lib'
 
 require 'zip'
 require 'find'
@@ -13,12 +13,13 @@ def self.find(path, zipFilePattern = /\.zip$/i)
       Find.find(path) do |fileName|
         yield(fileName)
         next unless zipFilePattern.match(fileName) && File.file?(fileName)
+
         begin
           Zip::File.foreach(fileName) do |zipEntry|
             yield(fileName + File::SEPARATOR + zipEntry.to_s)
           end
-        rescue Errno::EACCES => ex
-          puts ex
+        rescue Errno::EACCES => e
+          puts e
         end
       end
     end
@@ -31,7 +32,7 @@ def self.find_file(path, fileNamePattern, zipFilePattern = /\.zip$/i)
   end
 end
 
-if $0 == __FILE__
+if $PROGRAM_NAME == __FILE__
   module ZipFindConsoleRunner
     PATH_ARG_INDEX = 0
     FILENAME_PATTERN_ARG_INDEX = 1
@@ -47,14 +48,14 @@ def self.run(args)
     end
 
     def self.check_args(args)
-      if args.size != 3
-        usage
-        exit
-      end
+      return if args.size == 3
+
+      usage
+      exit
     end
 
     def self.usage
-      puts "Usage: #{$0} PATH ZIPFILENAME_PATTERN FILNAME_PATTERN"
+      puts "Usage: #{$PROGRAM_NAME} PATH ZIPFILENAME_PATTERN FILNAME_PATTERN"
     end
 
     def self.report_entry_found(fileName)
diff --git a/test/basic_zip_file_test.rb b/test/basic_zip_file_test.rb
index 9e490b4a..3d21ae89 100644
--- a/test/basic_zip_file_test.rb
+++ b/test/basic_zip_file_test.rb
@@ -10,7 +10,7 @@ def setup
 
   def test_entries
     assert_equal(TestZipFile::TEST_ZIP2.entry_names.sort,
-                 @zip_file.entries.entries.sort.map { |e| e.name })
+                 @zip_file.entries.entries.sort.map(&:name))
   end
 
   def test_each
diff --git a/test/case_sensitivity_test.rb b/test/case_sensitivity_test.rb
index 4aab1667..92fc0f6c 100644
--- a/test/case_sensitivity_test.rb
+++ b/test/case_sensitivity_test.rb
@@ -22,11 +22,11 @@ def test_add_case_sensitive
 
     zfRead = ::Zip::File.new(EMPTY_FILENAME)
     assert_equal(SRC_FILES.size, zfRead.entries.length)
-    SRC_FILES.each_with_index { |a, i|
+    SRC_FILES.each_with_index do |a, i|
       assert_equal(a.last, zfRead.entries[i].name)
       AssertEntry.assert_contents(a.first,
-                                  zfRead.get_input_stream(a.last) { |zis| zis.read })
-    }
+                                  zfRead.get_input_stream(a.last, &:read))
+    end
   end
 
   # Ensure that names are treated case insensitively when adding files and +case_insensitive_match = false+
@@ -56,14 +56,15 @@ def test_add_case_sensitive_read_case_insensitive
     zfRead = ::Zip::File.new(EMPTY_FILENAME)
     assert_equal(SRC_FILES.collect { |_fn, en| en.downcase }.uniq.size, zfRead.entries.length)
     assert_equal(SRC_FILES.last.last.downcase, zfRead.entries.first.name.downcase)
-    AssertEntry.assert_contents(SRC_FILES.last.first,
-                                zfRead.get_input_stream(SRC_FILES.last.last) { |zis| zis.read })
+    AssertEntry.assert_contents(
+      SRC_FILES.last.first, zfRead.get_input_stream(SRC_FILES.last.last, &:read)
+    )
   end
 
   private
 
   def assert_contains(zf, entryName, filename = entryName)
-    assert(zf.entries.detect { |e| e.name == entryName } != nil, "entry #{entryName} not in #{zf.entries.join(', ')} in zip file #{zf}")
+    refute_nil(zf.entries.detect { |e| e.name == entryName }, "entry #{entryName} not in #{zf.entries.join(', ')} in zip file #{zf}")
     assert_entry_contents(zf, entryName, filename) if File.exist?(filename)
   end
 end
diff --git a/test/central_directory_entry_test.rb b/test/central_directory_entry_test.rb
index fa0d8065..c060a4d3 100644
--- a/test/central_directory_entry_test.rb
+++ b/test/central_directory_entry_test.rb
@@ -63,7 +63,7 @@ def test_read_entry_from_truncated_zip_file
     fragment.extend(IOizeString)
     entry = ::Zip::Entry.new
     entry.read_c_dir_entry(fragment)
-    fail 'ZipError expected'
+    raise 'ZipError expected'
   rescue ::Zip::Error
   end
 end
diff --git a/test/central_directory_test.rb b/test/central_directory_test.rb
index 26be6424..28e12f4a 100644
--- a/test/central_directory_test.rb
+++ b/test/central_directory_test.rb
@@ -22,7 +22,7 @@ def test_read_from_invalid_stream
       cdir = ::Zip::CentralDirectory.new
       cdir.read_from_stream(zipFile)
     end
-    fail 'ZipError expected!'
+    raise 'ZipError expected!'
   rescue ::Zip::Error
   end
 
@@ -33,7 +33,7 @@ def test_read_from_truncated_zip_file
     fragment.extend(IOizeString)
     entry = ::Zip::CentralDirectory.new
     entry.read_from_stream(fragment)
-    fail 'ZipError expected'
+    raise 'ZipError expected'
   rescue ::Zip::Error
   end
 
diff --git a/test/deflater_test.rb b/test/deflater_test.rb
index d1970ce9..78c22dfc 100644
--- a/test/deflater_test.rb
+++ b/test/deflater_test.rb
@@ -43,7 +43,7 @@ def test_data_error
   private
 
   def load_file(fileName)
-    File.open(fileName, 'rb') { |f| f.read }
+    File.open(fileName, 'rb', &:read)
   end
 
   def deflate(data, fileName)
diff --git a/test/encryption_test.rb b/test/encryption_test.rb
index 46770a17..d3ed5ffb 100644
--- a/test/encryption_test.rb
+++ b/test/encryption_test.rb
@@ -14,14 +14,14 @@ def teardown
   end
 
   def test_encrypt
-    test_file = open(ENCRYPT_ZIP_TEST_FILE, 'rb').read
+    test_file = ::File.open(ENCRYPT_ZIP_TEST_FILE, 'rb').read
 
     @rand = [250, 143, 107, 13, 143, 22, 155, 75, 228, 150, 12]
     @output = ::Zip::DOSTime.stub(:now, ::Zip::DOSTime.new(2014, 12, 17, 15, 56, 24)) do
       Random.stub(:rand, ->(_range) { @rand.shift }) do
         Zip::OutputStream.write_buffer(::StringIO.new(''), Zip::TraditionalEncrypter.new('password')) do |zos|
           zos.put_next_entry('file1.txt')
-          zos.write open(INPUT_FILE1).read
+          zos.write ::File.open(INPUT_FILE1).read
         end.string
       end
     end
@@ -36,7 +36,7 @@ def test_decrypt
       entry = zis.get_next_entry
       assert_equal 'file1.txt', entry.name
       assert_equal 1327, entry.size
-      assert_equal open(INPUT_FILE1, 'r').read, zis.read
+      assert_equal ::File.open(INPUT_FILE1, 'r').read, zis.read
     end
   end
 end
diff --git a/test/errors_test.rb b/test/errors_test.rb
index 2c6adb2f..5e6260f8 100644
--- a/test/errors_test.rb
+++ b/test/errors_test.rb
@@ -1,5 +1,3 @@
-# encoding: utf-8
-
 require 'test_helper'
 
 class ErrorsTest < MiniTest::Test
diff --git a/test/extra_field_ut_test.rb b/test/extra_field_ut_test.rb
index ad2ab7a6..6b854978 100644
--- a/test/extra_field_ut_test.rb
+++ b/test/extra_field_ut_test.rb
@@ -1,7 +1,6 @@
 require 'test_helper'
 
 class ZipExtraFieldUTTest < MiniTest::Test
-
   PARSE_TESTS = [
     ["UT\x05\x00\x01PS>A", 0b001, true, true, false],
     ["UT\x05\x00\x02PS>A", 0b010, false, true, true],
diff --git a/test/file_extract_test.rb b/test/file_extract_test.rb
index a494f781..3992a1ad 100644
--- a/test/file_extract_test.rb
+++ b/test/file_extract_test.rb
@@ -20,7 +20,7 @@ def test_extract
 
       assert(File.exist?(EXTRACTED_FILENAME))
       AssertEntry.assert_contents(EXTRACTED_FILENAME,
-                                  zf.get_input_stream(ENTRY_TO_EXTRACT) { |is| is.read })
+                                  zf.get_input_stream(ENTRY_TO_EXTRACT, &:read))
 
       ::File.unlink(EXTRACTED_FILENAME)
 
@@ -29,7 +29,7 @@ def test_extract
 
       assert(File.exist?(EXTRACTED_FILENAME))
       AssertEntry.assert_contents(EXTRACTED_FILENAME,
-                                  entry.get_input_stream { |is| is.read })
+                                  entry.get_input_stream(&:read))
     end
   end
 
diff --git a/test/file_options_test.rb b/test/file_options_test.rb
index 1a73e980..61b86e85 100644
--- a/test/file_options_test.rb
+++ b/test/file_options_test.rb
@@ -24,9 +24,9 @@ def teardown
   def test_restore_permissions
     # Copy and set up files with different permissions.
     ::FileUtils.cp(TXTPATH, TXTPATH_600)
-    ::File.chmod(0600, TXTPATH_600)
+    ::File.chmod(0o600, TXTPATH_600)
     ::FileUtils.cp(TXTPATH, TXTPATH_755)
-    ::File.chmod(0755, TXTPATH_755)
+    ::File.chmod(0o755, TXTPATH_755)
 
     ::Zip::File.open(ZIPPATH, true) do |zip|
       zip.add(ENTRY_1, TXTPATH)
diff --git a/test/file_split_test.rb b/test/file_split_test.rb
index dfea837d..22dd1348 100644
--- a/test/file_split_test.rb
+++ b/test/file_split_test.rb
@@ -28,6 +28,7 @@ def test_split
     result = ::Zip::File.split(TEST_ZIP.zip_name, 65_536, false)
 
     return if result.nil?
+
     Dir["#{TEST_ZIP.zip_name}.*"].sort.each_with_index do |zip_file_name, index|
       File.open(zip_file_name, 'rb') do |zip_file|
         zip_file.read([::Zip::File::SPLIT_SIGNATURE].pack('V').size) if index == 0
@@ -42,7 +43,7 @@ def test_split
 
       assert(File.exist?(EXTRACTED_FILENAME))
       AssertEntry.assert_contents(EXTRACTED_FILENAME,
-                                  zf.get_input_stream(ENTRY_TO_EXTRACT) { |is| is.read })
+                                  zf.get_input_stream(ENTRY_TO_EXTRACT, &:read))
 
       File.unlink(EXTRACTED_FILENAME)
 
@@ -51,7 +52,7 @@ def test_split
 
       assert(File.exist?(EXTRACTED_FILENAME))
       AssertEntry.assert_contents(EXTRACTED_FILENAME,
-                                  entry.get_input_stream { |is| is.read })
+                                  entry.get_input_stream(&:read))
     end
   end
 end
diff --git a/test/file_test.rb b/test/file_test.rb
index d7f5cb8e..21aa72f7 100644
--- a/test/file_test.rb
+++ b/test/file_test.rb
@@ -57,7 +57,7 @@ def test_create_from_scratch_with_old_create_parameter
 
   def test_get_input_stream_stored_with_gpflag_bit3
     ::Zip::File.open('test/data/gpbit3stored.zip') do |zf|
-      assert_equal("foo\n", zf.read("foo.txt"))
+      assert_equal("foo\n", zf.read('foo.txt'))
     end
   end
 
@@ -106,14 +106,14 @@ def test_get_output_stream
   def test_open_buffer_with_string
     string = File.read('test/data/rubycode.zip')
     ::Zip::File.open_buffer string do |zf|
-      assert zf.entries.map { |e| e.name }.include?('zippedruby1.rb')
+      assert zf.entries.map(&:name).include?('zippedruby1.rb')
     end
   end
 
   def test_open_buffer_with_stringio
     string_io = StringIO.new File.read('test/data/rubycode.zip')
     ::Zip::File.open_buffer string_io do |zf|
-      assert zf.entries.map { |e| e.name }.include?('zippedruby1.rb')
+      assert zf.entries.map(&:name).include?('zippedruby1.rb')
     end
   end
 
@@ -131,7 +131,7 @@ def test_open_buffer_no_op_does_not_change_file
       # Note: this may change the file if it is opened with r+b instead of rb.
       # The 'extra fields' in this particular zip file get reordered.
       File.open(test_zip, 'rb') do |file|
-        Zip::File.open_buffer(file) do |zf|
+        Zip::File.open_buffer(file) do
           nil # do nothing
         end
       end
@@ -171,7 +171,7 @@ def test_open_buffer_with_io_and_block
   def test_open_buffer_without_block
     string_io = StringIO.new File.read('test/data/rubycode.zip')
     zf = ::Zip::File.open_buffer string_io
-    assert zf.entries.map { |e| e.name }.include?('zippedruby1.rb')
+    assert zf.entries.map(&:name).include?('zippedruby1.rb')
   end
 
   def test_cleans_up_tempfiles_after_close
@@ -201,7 +201,7 @@ def test_add
     assert_equal(1, zfRead.entries.length)
     assert_equal(entryName, zfRead.entries.first.name)
     AssertEntry.assert_contents(srcFile,
-                                zfRead.get_input_stream(entryName) { |zis| zis.read })
+                                zfRead.get_input_stream(entryName, &:read))
   end
 
   def test_add_stored
@@ -221,7 +221,7 @@ def test_add_stored
     assert_equal(entry.size, entry.compressed_size)
     assert_equal(::Zip::Entry::STORED, entry.compression_method)
     AssertEntry.assert_contents(srcFile,
-                                zfRead.get_input_stream(entryName) { |zis| zis.read })
+                                zfRead.get_input_stream(entryName, &:read))
   end
 
   def test_recover_permissions_after_add_files_to_archive
@@ -250,7 +250,10 @@ def test_add_existing_entry_name_replace
     replacedEntry = nil
     ::Zip::File.open(TEST_ZIP.zip_name) do |zf|
       replacedEntry = zf.entries.first.name
-      zf.add(replacedEntry, 'test/data/file2.txt') { gotCalled = true; true }
+      zf.add(replacedEntry, 'test/data/file2.txt') do
+        gotCalled = true
+        true
+      end
     end
     assert(gotCalled)
     ::Zip::File.open(TEST_ZIP.zip_name) do |zf|
@@ -274,15 +277,15 @@ def test_remove
     FileUtils.cp(TestZipFile::TEST_ZIP2.zip_name, TEST_ZIP.zip_name)
 
     zf = ::Zip::File.new(TEST_ZIP.zip_name)
-    assert(zf.entries.map { |e| e.name }.include?(entryToRemove))
+    assert(zf.entries.map(&:name).include?(entryToRemove))
     zf.remove(entryToRemove)
-    assert(!zf.entries.map { |e| e.name }.include?(entryToRemove))
-    assert_equal(zf.entries.map { |x| x.name }.sort, remainingEntries.sort)
+    assert(!zf.entries.map(&:name).include?(entryToRemove))
+    assert_equal(zf.entries.map(&:name).sort, remainingEntries.sort)
     zf.close
 
     zfRead = ::Zip::File.new(TEST_ZIP.zip_name)
-    assert(!zfRead.entries.map { |e| e.name }.include?(entryToRemove))
-    assert_equal(zfRead.entries.map { |x| x.name }.sort, remainingEntries.sort)
+    assert(!zfRead.entries.map(&:name).include?(entryToRemove))
+    assert_equal(zfRead.entries.map(&:name).sort, remainingEntries.sort)
     zfRead.close
   end
 
@@ -290,21 +293,21 @@ def test_rename
     entryToRename, * = TEST_ZIP.entry_names
 
     zf = ::Zip::File.new(TEST_ZIP.zip_name)
-    assert(zf.entries.map { |e| e.name }.include?(entryToRename))
+    assert(zf.entries.map(&:name).include?(entryToRename))
 
     contents = zf.read(entryToRename)
     newName = 'changed entry name'
-    assert(!zf.entries.map { |e| e.name }.include?(newName))
+    assert(!zf.entries.map(&:name).include?(newName))
 
     zf.rename(entryToRename, newName)
-    assert(zf.entries.map { |e| e.name }.include?(newName))
+    assert(zf.entries.map(&:name).include?(newName))
 
     assert_equal(contents, zf.read(newName))
 
     zf.close
 
     zfRead = ::Zip::File.new(TEST_ZIP.zip_name)
-    assert(zfRead.entries.map { |e| e.name }.include?(newName))
+    assert(zfRead.entries.map(&:name).include?(newName))
     assert_equal(contents, zfRead.read(newName))
     zfRead.close
   end
@@ -349,7 +352,7 @@ def test_rename_to_existing_entry
     end
 
     ::Zip::File.open(TEST_ZIP.zip_name) do |zf|
-      assert_equal(oldEntries.sort.map { |e| e.name }, zf.entries.sort.map { |e| e.name })
+      assert_equal(oldEntries.sort.map(&:name), zf.entries.sort.map(&:name))
     end
   end
 
@@ -361,14 +364,17 @@ def test_rename_to_existing_entry_overwrite
     renamedEntryName = nil
     ::Zip::File.open(TEST_ZIP.zip_name) do |zf|
       renamedEntryName = zf.entries[0].name
-      zf.rename(zf.entries[0], zf.entries[1].name) { gotCalled = true; true }
+      zf.rename(zf.entries[0], zf.entries[1].name) do
+        gotCalled = true
+        true
+      end
     end
 
     assert(gotCalled)
     oldEntries.delete_if { |e| e.name == renamedEntryName }
     ::Zip::File.open(TEST_ZIP.zip_name) do |zf|
-      assert_equal(oldEntries.sort.map { |e| e.name },
-                   zf.entries.sort.map { |e| e.name })
+      assert_equal(oldEntries.sort.map(&:name),
+                   zf.entries.sort.map(&:name))
     end
   end
 
@@ -401,13 +407,16 @@ def test_replace
     zf.close
     zfRead = ::Zip::File.new(TEST_ZIP.zip_name)
     AssertEntry.assert_contents(newEntrySrcFilename,
-                                zfRead.get_input_stream(entryToReplace) { |is| is.read })
+                                zfRead.get_input_stream(entryToReplace, &:read))
     AssertEntry.assert_contents(TEST_ZIP.entry_names[0],
-                                zfRead.get_input_stream(TEST_ZIP.entry_names[0]) { |is| is.read })
+                                zfRead.get_input_stream(TEST_ZIP.entry_names[0],
+                                                        &:read))
     AssertEntry.assert_contents(TEST_ZIP.entry_names[1],
-                                zfRead.get_input_stream(TEST_ZIP.entry_names[1]) { |is| is.read })
+                                zfRead.get_input_stream(TEST_ZIP.entry_names[1],
+                                                        &:read))
     AssertEntry.assert_contents(TEST_ZIP.entry_names[3],
-                                zfRead.get_input_stream(TEST_ZIP.entry_names[3]) { |is| is.read })
+                                zfRead.get_input_stream(TEST_ZIP.entry_names[3],
+                                                        &:read))
     zfRead.close
   end
 
@@ -426,8 +435,8 @@ def test_commit
     zf.commit
 
     zfRead = ::Zip::File.new(TEST_ZIP.zip_name)
-    assert(zfRead.entries.detect { |e| e.name == newName } != nil)
-    assert(zfRead.entries.detect { |e| e.name == oldName }.nil?)
+    refute_nil(zfRead.entries.detect { |e| e.name == newName })
+    assert_nil(zfRead.entries.detect { |e| e.name == oldName })
     zfRead.close
 
     zf.close
@@ -445,8 +454,8 @@ def test_double_commit(filename = 'test/data/generated/double_commit_test.zip')
     zf.commit
     zf.close
     zf2 = ::Zip::File.open(filename)
-    assert(zf2.entries.detect { |e| e.name == 'test1.txt' } != nil)
-    assert(zf2.entries.detect { |e| e.name == 'test2.txt' } != nil)
+    refute_nil(zf2.entries.detect { |e| e.name == 'test1.txt' })
+    refute_nil(zf2.entries.detect { |e| e.name == 'test2.txt' })
     res = system("unzip -tqq #{filename}")
     assert_equal(res, true)
   end
@@ -465,8 +474,8 @@ def test_write_buffer
     buffer = zf.write_buffer(io)
     File.open(TEST_ZIP.zip_name, 'wb') { |f| f.write buffer.string }
     zfRead = ::Zip::File.new(TEST_ZIP.zip_name)
-    assert(zfRead.entries.detect { |e| e.name == newName } != nil)
-    assert(zfRead.entries.detect { |e| e.name == oldName }.nil?)
+    refute_nil(zfRead.entries.detect { |e| e.name == newName })
+    assert_nil(zfRead.entries.detect { |e| e.name == oldName })
     zfRead.close
 
     zf.close
@@ -549,7 +558,7 @@ def test_compound2
         zf.add(filename, filename)
         assert_contains(zf, filename)
       end
-      assert_equal(zf.entries.sort.map { |e| e.name }, TestFiles::ASCII_TEST_FILES)
+      assert_equal(zf.entries.sort.map(&:name), TestFiles::ASCII_TEST_FILES)
 
       zf.rename(TestFiles::ASCII_TEST_FILES[0], 'newName')
       assert_not_contains(zf, TestFiles::ASCII_TEST_FILES[0])
@@ -582,7 +591,7 @@ def test_change_comment
   def test_preserve_file_order
     entryNames = nil
     ::Zip::File.open(TEST_ZIP.zip_name) do |zf|
-      entryNames = zf.entries.map { |e| e.to_s }
+      entryNames = zf.entries.map(&:to_s)
       zf.get_output_stream('a.txt') { |os| os.write 'this is a.txt' }
       zf.get_output_stream('z.txt') { |os| os.write 'this is z.txt' }
       zf.get_output_stream('k.txt') { |os| os.write 'this is k.txt' }
@@ -590,16 +599,16 @@ def test_preserve_file_order
     end
 
     ::Zip::File.open(TEST_ZIP.zip_name) do |zf|
-      assert_equal(entryNames, zf.entries.map { |e| e.to_s })
-      entries = zf.entries.sort_by { |e| e.name }.reverse
+      assert_equal(entryNames, zf.entries.map(&:to_s))
+      entries = zf.entries.sort_by(&:name).reverse
       entries.each do |e|
         zf.remove e
         zf.get_output_stream(e) { |os| os.write 'foo' }
       end
-      entryNames = entries.map { |e| e.to_s }
+      entryNames = entries.map(&:to_s)
     end
     ::Zip::File.open(TEST_ZIP.zip_name) do |zf|
-      assert_equal(entryNames, zf.entries.map { |e| e.to_s })
+      assert_equal(entryNames, zf.entries.map(&:to_s))
     end
   end
 
@@ -617,6 +626,7 @@ def test_streaming
       Zip::File.open_buffer(f) do |zipfile|
         zipfile.each do |entry|
           next unless entry.name =~ /README.md/
+
           data = zipfile.read(entry)
         end
       end
@@ -671,11 +681,11 @@ def test_find_get_entry
   private
 
   def assert_contains(zf, entryName, filename = entryName)
-    assert(zf.entries.detect { |e| e.name == entryName } != nil, "entry #{entryName} not in #{zf.entries.join(', ')} in zip file #{zf}")
+    refute_nil(zf.entries.detect { |e| e.name == entryName }, "entry #{entryName} not in #{zf.entries.join(', ')} in zip file #{zf}")
     assert_entry_contents(zf, entryName, filename) if File.exist?(filename)
   end
 
   def assert_not_contains(zf, entryName)
-    assert(zf.entries.detect { |e| e.name == entryName }.nil?, "entry #{entryName} in #{zf.entries.join(', ')} in zip file #{zf}")
+    assert_nil(zf.entries.detect { |e| e.name == entryName }, "entry #{entryName} in #{zf.entries.join(', ')} in zip file #{zf}")
   end
 end
diff --git a/test/filesystem/file_nonmutating_test.rb b/test/filesystem/file_nonmutating_test.rb
index 62486666..cfe18ade 100644
--- a/test/filesystem/file_nonmutating_test.rb
+++ b/test/filesystem/file_nonmutating_test.rb
@@ -80,7 +80,7 @@ def test_new
     end
     begin
       is = @zip_file.file.new('file1') do
-        fail 'should not call block'
+        raise 'should not call block'
       end
     ensure
       is.close if is
@@ -434,12 +434,14 @@ def test_glob
     ::Zip::File.open('test/data/globTest.zip') do |zf|
       {
         'globTest/foo.txt' => ['globTest/foo.txt'],
-        '*/foo.txt' => ['globTest/foo.txt'],
-        '**/foo.txt' => ['globTest/foo.txt', 'globTest/foo/bar/baz/foo.txt'],
-        '*/foo/**/*.txt' => ['globTest/foo/bar/baz/foo.txt']
+        '*/foo.txt'        => ['globTest/foo.txt'],
+        '**/foo.txt'       => [
+          'globTest/foo.txt', 'globTest/foo/bar/baz/foo.txt'
+        ],
+        '*/foo/**/*.txt'   => ['globTest/foo/bar/baz/foo.txt']
       }.each do |spec, expected_results|
         results = zf.glob(spec)
-        assert results.all? { |entry| entry.is_a? ::Zip::Entry }
+        assert(results.all? { |entry| entry.kind_of? ::Zip::Entry })
 
         result_strings = results.map(&:to_s)
         missing_matches = expected_results - result_strings
@@ -466,12 +468,12 @@ def test_popen
     if Zip::RUNNING_ON_WINDOWS
       # This is pretty much projectile vomit but it allows the test to be
       # run on windows also
-      system_dir = ::File.popen('dir') { |f| f.read }.gsub(/Dir\(s\).*$/, '')
-      zipfile_dir = @zip_file.file.popen('dir') { |f| f.read }.gsub(/Dir\(s\).*$/, '')
+      system_dir = ::File.popen('dir', &:read).gsub(/Dir\(s\).*$/, '')
+      zipfile_dir = @zip_file.file.popen('dir', &:read).gsub(/Dir\(s\).*$/, '')
       assert_equal(system_dir, zipfile_dir)
     else
-      assert_equal(::File.popen('ls') { |f| f.read },
-                   @zip_file.file.popen('ls') { |f| f.read })
+      assert_equal(::File.popen('ls', &:read),
+                   @zip_file.file.popen('ls', &:read))
     end
   end
 
diff --git a/test/gentestfiles.rb b/test/gentestfiles.rb
index 3e76e7d0..acdada45 100755
--- a/test/gentestfiles.rb
+++ b/test/gentestfiles.rb
@@ -52,6 +52,7 @@ def create_random_binary(filename, size)
     def ensure_dir(name)
       if File.exist?(name)
         return if File.stat(name).directory?
+
         File.delete(name)
       end
       Dir.mkdir(name)
@@ -71,8 +72,12 @@ def initialize(zip_name, entry_names, comment = '')
   end
 
   def self.create_test_zips
-    raise "failed to create test zip '#{TEST_ZIP1.zip_name}'" unless system("/usr/bin/zip -q #{TEST_ZIP1.zip_name} test/data/file2.txt")
-    raise "failed to remove entry from '#{TEST_ZIP1.zip_name}'" unless system("/usr/bin/zip -q #{TEST_ZIP1.zip_name} -d test/data/file2.txt")
+    raise "failed to create test zip '#{TEST_ZIP1.zip_name}'" \
+      unless system("/usr/bin/zip -q #{TEST_ZIP1.zip_name} test/data/file2.txt")
+    raise "failed to remove entry from '#{TEST_ZIP1.zip_name}'" \
+      unless system(
+        "/usr/bin/zip -q #{TEST_ZIP1.zip_name} -d test/data/file2.txt"
+      )
 
     File.open('test/data/generated/empty.txt', 'w') {}
     File.open('test/data/generated/empty_chmod640.txt', 'w') {}
@@ -93,33 +98,57 @@ def self.create_test_zips
       file << testBinaryPattern << rand << "\0" while file.tell < 6E5
     end
 
-    raise "failed to create test zip '#{TEST_ZIP2.zip_name}'" unless system("/usr/bin/zip -q #{TEST_ZIP2.zip_name} #{TEST_ZIP2.entry_names.join(' ')}")
+    raise "failed to create test zip '#{TEST_ZIP2.zip_name}'" \
+      unless system(
+        "/usr/bin/zip -q #{TEST_ZIP2.zip_name} #{TEST_ZIP2.entry_names.join(' ')}"
+      )
 
     if RUBY_PLATFORM =~ /mswin|mingw|cygwin/
-      raise "failed to add comment to test zip '#{TEST_ZIP2.zip_name}'" unless system("echo #{TEST_ZIP2.comment}| /usr/bin/zip -zq #{TEST_ZIP2.zip_name}\"")
+      raise "failed to add comment to test zip '#{TEST_ZIP2.zip_name}'" \
+        unless system(
+          "echo #{TEST_ZIP2.comment}| /usr/bin/zip -zq #{TEST_ZIP2.zip_name}\""
+        )
     else
       # without bash system interprets everything after echo as parameters to
       # echo including | zip -z ...
-      raise "failed to add comment to test zip '#{TEST_ZIP2.zip_name}'" unless system("bash -c \"echo #{TEST_ZIP2.comment} | /usr/bin/zip -zq #{TEST_ZIP2.zip_name}\"")
+      raise "failed to add comment to test zip '#{TEST_ZIP2.zip_name}'" \
+        unless system(
+          "bash -c \"echo #{TEST_ZIP2.comment} | /usr/bin/zip -zq #{TEST_ZIP2.zip_name}\""
+        )
     end
 
-    raise "failed to create test zip '#{TEST_ZIP3.zip_name}'" unless system("/usr/bin/zip -q #{TEST_ZIP3.zip_name} #{TEST_ZIP3.entry_names.join(' ')}")
+    raise "failed to create test zip '#{TEST_ZIP3.zip_name}'" \
+      unless system(
+        "/usr/bin/zip -q #{TEST_ZIP3.zip_name} #{TEST_ZIP3.entry_names.join(' ')}"
+      )
 
-    raise "failed to create test zip '#{TEST_ZIP4.zip_name}'" unless system("/usr/bin/zip -q #{TEST_ZIP4.zip_name} #{TEST_ZIP4.entry_names.join(' ')}")
-  rescue
+    raise "failed to create test zip '#{TEST_ZIP4.zip_name}'" \
+      unless system(
+        "/usr/bin/zip -q #{TEST_ZIP4.zip_name} #{TEST_ZIP4.entry_names.join(' ')}"
+      )
+  rescue StandardError
     # If there are any Windows developers wanting to use a command line zip.exe
     # to help create the following files, there's a free one available from
     # http://stahlworks.com/dev/index.php?tool=zipunzip
     # that works with the above code
-    raise $!.to_s +
+    raise $ERROR_INFO.to_s +
           "\n\nziptest.rb requires the Info-ZIP program 'zip' in the path\n" \
           "to create test data. If you don't have it you can download\n" \
           'the necessary test files at http://sf.net/projects/rubyzip.'
   end
 
   TEST_ZIP1 = TestZipFile.new('test/data/generated/empty.zip', [])
-  TEST_ZIP2 = TestZipFile.new('test/data/generated/5entry.zip', %w[test/data/generated/longAscii.txt test/data/generated/empty.txt test/data/generated/empty_chmod640.txt test/data/generated/short.txt test/data/generated/longBinary.bin],
-                              'my zip comment')
+  TEST_ZIP2 = TestZipFile.new(
+    'test/data/generated/5entry.zip',
+    %w[
+      test/data/generated/longAscii.txt
+      test/data/generated/empty.txt
+      test/data/generated/empty_chmod640.txt
+      test/data/generated/short.txt
+      test/data/generated/longBinary.bin
+    ],
+    'my zip comment'
+  )
   TEST_ZIP3 = TestZipFile.new('test/data/generated/test1.zip', %w[test/data/file1.txt])
   TEST_ZIP4 = TestZipFile.new('test/data/generated/zipWithDir.zip', ['test/data/file1.txt',
                                                                      TestFiles::EMPTY_TEST_DIR])
diff --git a/test/ioextras/abstract_input_stream_test.rb b/test/ioextras/abstract_input_stream_test.rb
index 3ae005d1..f8986b84 100644
--- a/test/ioextras/abstract_input_stream_test.rb
+++ b/test/ioextras/abstract_input_stream_test.rb
@@ -4,8 +4,8 @@
 class AbstractInputStreamTest < MiniTest::Test
   # AbstractInputStream subclass that provides a read method
 
-  TEST_LINES = ["Hello world#{$/}",
-                "this is the second line#{$/}",
+  TEST_LINES = ["Hello world#{$INPUT_RECORD_SEPARATOR}",
+                "this is the second line#{$INPUT_RECORD_SEPARATOR}",
                 'this is the last line']
   TEST_STRING = TEST_LINES.join
   class TestAbstractInputStream
@@ -50,7 +50,7 @@ def test_gets
 
   def test_gets_multi_char_seperator
     assert_equal('Hell', @io.gets('ll'))
-    assert_equal("o world#{$/}this is the second l", @io.gets('d l'))
+    assert_equal("o world#{$INPUT_RECORD_SEPARATOR}this is the second l", @io.gets('d l'))
   end
 
   LONG_LINES = [
@@ -95,7 +95,7 @@ def test_readline
     test_gets
     begin
       @io.readline
-      fail 'EOFError expected'
+      raise 'EOFError expected'
     rescue EOFError
     end
   end
diff --git a/test/ioextras/abstract_output_stream_test.rb b/test/ioextras/abstract_output_stream_test.rb
index 3077db43..17b31a78 100644
--- a/test/ioextras/abstract_output_stream_test.rb
+++ b/test/ioextras/abstract_output_stream_test.rb
@@ -20,8 +20,8 @@ def <<(data)
   def setup
     @output_stream = TestOutputStream.new
 
-    @origCommaSep = $,
-    @origOutputSep = $\
+    @origCommaSep = $OUTPUT_FIELD_SEPARATOR
+    @origOutputSep = $OUTPUT_RECORD_SEPARATOR
   end
 
   def teardown
diff --git a/test/local_entry_test.rb b/test/local_entry_test.rb
index 666a63a0..b02deb67 100644
--- a/test/local_entry_test.rb
+++ b/test/local_entry_test.rb
@@ -46,7 +46,7 @@ def test_read_local_entry_from_truncated_zip_file
     zipFragment.extend(IOizeString).reset
     entry = ::Zip::Entry.new
     entry.read_local_entry(zipFragment)
-    fail 'ZipError expected'
+    raise 'ZipError expected'
   rescue ::Zip::Error
   end
 
diff --git a/test/output_stream_test.rb b/test/output_stream_test.rb
index a7725e22..40205076 100644
--- a/test/output_stream_test.rb
+++ b/test/output_stream_test.rb
@@ -57,11 +57,11 @@ def test_cannot_open_file
     name = TestFiles::EMPTY_TEST_DIR
     begin
       ::Zip::OutputStream.open(name)
-    rescue Exception
-      assert($!.kind_of?(Errno::EISDIR) || # Linux
-                 $!.kind_of?(Errno::EEXIST) || # Windows/cygwin
-                 $!.kind_of?(Errno::EACCES), # Windows
-             "Expected Errno::EISDIR (or on win/cygwin: Errno::EEXIST), but was: #{$!.class}")
+    rescue SystemCallError
+      assert($ERROR_INFO.kind_of?(Errno::EISDIR) || # Linux
+                 $ERROR_INFO.kind_of?(Errno::EEXIST) || # Windows/cygwin
+                 $ERROR_INFO.kind_of?(Errno::EACCES), # Windows
+             "Expected Errno::EISDIR (or on win/cygwin: Errno::EEXIST), but was: #{$ERROR_INFO.class}")
     end
   end
 
@@ -90,7 +90,8 @@ def test_put_next_entry_using_zip_entry_creates_entries_with_correct_timestamps
 
     ::Zip::InputStream.open(TEST_ZIP.zip_name) do |io|
       while (entry = io.get_next_entry)
-        assert(::Zip::DOSTime.at(file.mtime).dos_equals(::Zip::DOSTime.at(entry.mtime))) # Compare DOS Times, since they are stored with two seconds accuracy
+        # Compare DOS Times, since they are stored with two seconds accuracy
+        assert(::Zip::DOSTime.at(file.mtime).dos_equals(::Zip::DOSTime.at(entry.mtime)))
       end
     end
   end
diff --git a/test/path_traversal_test.rb b/test/path_traversal_test.rb
index 8b6f67d5..47c7e30f 100644
--- a/test/path_traversal_test.rb
+++ b/test/path_traversal_test.rb
@@ -62,9 +62,9 @@ def test_leading_dot_dot
 
   def test_non_leading_dot_dot_with_existing_folder
     entries = {
-      'tmp/' => '',
+      'tmp/'          => '',
       'tmp/../../moo' => /WARNING: skipped \'tmp\/\.\.\/\.\.\/moo\'/
-     }
+    }
     in_tmpdir do
       extract_paths('relative1.zip', entries)
       assert Dir.exist?('tmp')
@@ -92,7 +92,7 @@ def test_file_symlink
   def test_directory_symlink
     # Can't create tmp/moo, because the tmp symlink is skipped.
     entries = {
-      'tmp' => /WARNING: skipped symlink \'tmp\'/,
+      'tmp'     => /WARNING: skipped symlink \'tmp\'/,
       'tmp/moo' => :error
     }
     in_tmpdir do
@@ -104,8 +104,8 @@ def test_directory_symlink
   def test_two_directory_symlinks_a
     # Can't create par/moo because the symlinks are skipped.
     entries = {
-      'cur' => /WARNING: skipped symlink \'cur\'/,
-      'par' => /WARNING: skipped symlink \'par\'/,
+      'cur'     => /WARNING: skipped symlink \'cur\'/,
+      'par'     => /WARNING: skipped symlink \'par\'/,
       'par/moo' => :error
     }
     in_tmpdir do
@@ -119,7 +119,7 @@ def test_two_directory_symlinks_a
   def test_two_directory_symlinks_b
     # Can't create par/moo, because the symlinks are skipped.
     entries = {
-      'cur' => /WARNING: skipped symlink \'cur\'/,
+      'cur'     => /WARNING: skipped symlink \'cur\'/,
       'cur/par' => /WARNING: skipped symlink \'cur\/par\'/,
       'par/moo' => :error
     }
@@ -132,7 +132,7 @@ def test_two_directory_symlinks_b
 
   def test_entry_name_with_absolute_path_does_not_extract
     entries = {
-      '/tmp/' => /WARNING: skipped \'\/tmp\/\'/,
+      '/tmp/'         => /WARNING: skipped \'\/tmp\/\'/,
       '/tmp/file.txt' => /WARNING: skipped \'\/tmp\/file.txt\'/
     }
     in_tmpdir do
@@ -156,7 +156,7 @@ def test_entry_name_with_absolute_path_extract_when_given_different_path
   def test_entry_name_with_relative_symlink
     # Doesn't create the symlink path, so can't create path/file.txt.
     entries = {
-      'path' => /WARNING: skipped symlink \'path\'/,
+      'path'          => /WARNING: skipped symlink \'path\'/,
       'path/file.txt' => :error
     }
     in_tmpdir do
diff --git a/test/settings_test.rb b/test/settings_test.rb
index 7c1331a6..ab5aa223 100644
--- a/test/settings_test.rb
+++ b/test/settings_test.rb
@@ -18,7 +18,7 @@ def teardown
   end
 
   def open_zip(&aProc)
-    assert(!aProc.nil?)
+    refute_nil(aProc)
     ::Zip::File.open(TestZipFile::TEST_ZIP4.zip_name, &aProc)
   end
 
@@ -89,7 +89,7 @@ def test_true_warn_invalid_date
   private
 
   def assert_contains(zf, entryName, filename = entryName)
-    assert(zf.entries.detect { |e| e.name == entryName } != nil, "entry #{entryName} not in #{zf.entries.join(', ')} in zip file #{zf}")
+    refute_nil(zf.entries.detect { |e| e.name == entryName }, "entry #{entryName} not in #{zf.entries.join(', ')} in zip file #{zf}")
     assert_entry_contents(zf, entryName, filename) if File.exist?(filename)
   end
 end
diff --git a/test/stored_support_test.rb b/test/stored_support_test.rb
index 8260e4a9..28836b9e 100644
--- a/test/stored_support_test.rb
+++ b/test/stored_support_test.rb
@@ -10,12 +10,12 @@ def test_read
     Zip::InputStream.open(STORED_ZIP_TEST_FILE) do |zis|
       entry = zis.get_next_entry
       assert_equal 'file1.txt', entry.name
-      assert_equal 1327, entry.size
-      assert_equal open(INPUT_FILE1, 'r').read, zis.read
+      assert_equal 1_327, entry.size
+      assert_equal ::File.open(INPUT_FILE1, 'r').read, zis.read
       entry = zis.get_next_entry
       assert_equal 'file2.txt', entry.name
-      assert_equal 41234, entry.size
-      assert_equal open(INPUT_FILE2, 'r').read, zis.read
+      assert_equal 41_234, entry.size
+      assert_equal ::File.open(INPUT_FILE2, 'r').read, zis.read
     end
   end
 
@@ -23,12 +23,12 @@ def test_encrypted_read
     Zip::InputStream.open(ENCRYPTED_STORED_ZIP_TEST_FILE, 0, Zip::TraditionalDecrypter.new('password')) do |zis|
       entry = zis.get_next_entry
       assert_equal 'file1.txt', entry.name
-      assert_equal 1327, entry.size
-      assert_equal open(INPUT_FILE1, 'r').read, zis.read
+      assert_equal 1_327, entry.size
+      assert_equal ::File.open(INPUT_FILE1, 'r').read, zis.read
       entry = zis.get_next_entry
       assert_equal 'file2.txt', entry.name
-      assert_equal 41234, entry.size
-      assert_equal open(INPUT_FILE2, 'r').read, zis.read
+      assert_equal 41_234, entry.size
+      assert_equal ::File.open(INPUT_FILE2, 'r').read, zis.read
     end
   end
 end
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 224a1eb2..0e14b6da 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -24,7 +24,7 @@ module IOizeString
 
   def read(count = nil)
     @tell ||= 0
-    count = size unless count
+    count ||= size
     retVal = slice(@tell, count)
     @tell += count
     retVal
@@ -42,11 +42,10 @@ def seek(index, offset)
     else
       raise 'Error in test method IOizeString::seek'
     end
-    if newPos < 0 || newPos >= size
-      raise Errno::EINVAL
-    else
-      @tell = newPos
-    end
+
+    raise Errno::EINVAL if newPos < 0 || newPos >= size
+
+    @tell = newPos
   end
 
   def reset
@@ -62,7 +61,7 @@ module DecompressorTests
   def setup
     @refText = ''
     File.open(TEST_FILE) { |f| @refText = f.read }
-    @refLines = @refText.split($/)
+    @refLines = @refText.split($INPUT_RECORD_SEPARATOR)
   end
 
   def test_read_everything
@@ -96,7 +95,7 @@ def assert_entry_contents_for_stream(filename, zis, entryName)
         if (expected && actual) && (expected.length > 400 || actual.length > 400)
           zipEntryFilename = entryName + '.zipEntry'
           File.open(zipEntryFilename, 'wb') { |entryfile| entryfile << actual }
-          fail("File '#{filename}' is different from '#{zipEntryFilename}'")
+          raise("File '#{filename}' is different from '#{zipEntryFilename}'")
         else
           assert_equal(expected, actual)
         end
@@ -107,14 +106,14 @@ def assert_entry_contents_for_stream(filename, zis, entryName)
   def self.assert_contents(filename, aString)
     fileContents = ''
     File.open(filename, 'rb') { |f| fileContents = f.read }
-    if fileContents != aString
-      if fileContents.length > 400 || aString.length > 400
-        stringFile = filename + '.other'
-        File.open(stringFile, 'wb') { |f| f << aString }
-        fail("File '#{filename}' is different from contents of string stored in '#{stringFile}'")
-      else
-        assert_equal(fileContents, aString)
-      end
+    return unless fileContents != aString
+
+    if fileContents.length > 400 || aString.length > 400
+      stringFile = filename + '.other'
+      File.open(stringFile, 'wb') { |f| f << aString }
+      raise("File '#{filename}' is different from contents of string stored in '#{stringFile}'")
+    else
+      assert_equal(fileContents, aString)
     end
   end
 
@@ -194,18 +193,21 @@ module ExtraAssertions
   def assert_forwarded(anObject, method, retVal, *expectedArgs)
     callArgs = nil
     setCallArgsProc = proc { |args| callArgs = args }
-    anObject.instance_eval <<-"end_eval"
+    anObject.instance_eval <<-END_EVAL, __FILE__, __LINE__ + 1
       alias #{method}_org #{method}
       def #{method}(*args)
         ObjectSpace._id2ref(#{setCallArgsProc.object_id}).call(args)
         ObjectSpace._id2ref(#{retVal.object_id})
         end
-    end_eval
+    END_EVAL
 
     assert_equal(retVal, yield) # Invoke test
     assert_equal(expectedArgs, callArgs)
   ensure
-    anObject.instance_eval "undef #{method}; alias #{method} #{method}_org"
+    anObject.instance_eval <<-END_EVAL, __FILE__, __LINE__ + 1
+      undef #{method}
+      alias #{method} #{method}_org
+    END_EVAL
   end
 end
 
diff --git a/test/unicode_file_names_and_comments_test.rb b/test/unicode_file_names_and_comments_test.rb
index aac3e256..4d2fc20f 100644
--- a/test/unicode_file_names_and_comments_test.rb
+++ b/test/unicode_file_names_and_comments_test.rb
@@ -1,5 +1,3 @@
-# encoding: utf-8
-
 require 'test_helper'
 
 class ZipUnicodeFileNamesAndComments < MiniTest::Test