Move spec/rubyspec to spec/ruby for consistency

* Other ruby implementations use the spec/ruby directory.
  [Misc #13792] [ruby-core:82287]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59979 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

spec/ruby/.gitignore

@@ -0,0 +1,5 @@
+/Gemfile.lock
+/rubyspec_temp
+/ext
+/.ruby-version
+/.ruby-gemset

spec/ruby/.rubocop.yml

@@ -0,0 +1,40 @@
+inherit_from: .rubocop_todo.yml
+
+AllCops:
+  TargetRubyVersion: 2.4
+  DisplayCopNames: true
+  Exclude:
+    - command_line/fixtures/bad_syntax.rb
+  DisabledByDefault: true
+
+Lint:
+  Enabled: true
+
+Lint/AssignmentInCondition:
+  Enabled: false
+
+Lint/LiteralInCondition:
+  Enabled: false
+
+Lint/UnifiedInteger:
+  Enabled: false
+
+Lint/UnusedBlockArgument:
+  Enabled: false
+
+Lint/UnusedMethodArgument:
+  Enabled: false
+
+Lint/UselessAssignment:
+  Enabled: false
+
+Lint/UselessComparison:
+  Enabled: false
+
+# The cop registers too many false positives to `.should == something`
+Lint/Void:
+  Enabled: false
+
+Lint/EmptyExpression:
+  Exclude:
+    - 'language/**/*.rb'

spec/ruby/.rubocop_todo.yml

@@ -0,0 +1,211 @@
+# This configuration was generated by
+# `rubocop --auto-gen-config`
+# on 2017-06-18 19:12:38 +0200 using RuboCop version 0.49.1.
+# 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: 6
+Lint/AmbiguousBlockAssociation:
+  Exclude:
+    - 'core/kernel/trace_var_spec.rb'
+    - 'language/fixtures/argv_encoding.rb'
+    - 'language/fixtures/break.rb'
+    - 'shared/process/abort.rb'
+
+# Offense count: 3
+Lint/CircularArgumentReference:
+  Exclude:
+    - 'language/block_spec.rb'
+    - 'language/def_spec.rb'
+    - 'language/lambda_spec.rb'
+
+# Offense count: 2
+Lint/DuplicateCaseCondition:
+  Exclude:
+    - 'language/case_spec.rb'
+
+# Offense count: 6
+Lint/DuplicateMethods:
+  Exclude:
+    - 'core/array/fixtures/encoded_strings.rb'
+    - 'core/method/fixtures/classes.rb'
+    - 'core/module/fixtures/classes.rb'
+    - 'core/unboundmethod/fixtures/classes.rb'
+    - 'fixtures/class.rb'
+
+# Offense count: 4
+Lint/EmptyWhen:
+  Exclude:
+    - 'language/case_spec.rb'
+
+# Offense count: 5
+Lint/EnsureReturn:
+  Exclude:
+    - 'language/fixtures/ensure.rb'
+    - 'language/fixtures/return.rb'
+    - 'language/return_spec.rb'
+
+# Offense count: 10
+Lint/FloatOutOfRange:
+  Exclude:
+    - 'core/string/modulo_spec.rb'
+
+# Offense count: 46
+Lint/FormatParameterMismatch:
+  Exclude:
+    - 'core/kernel/sprintf_spec.rb'
+    - 'core/string/modulo_spec.rb'
+
+# Offense count: 25
+Lint/HandleExceptions:
+  Enabled: false
+
+# Offense count: 2
+Lint/ImplicitStringConcatenation:
+  Exclude:
+    - 'language/string_spec.rb'
+
+# Offense count: 4
+Lint/IneffectiveAccessModifier:
+  Exclude:
+    - 'core/kernel/fixtures/classes.rb'
+    - 'core/module/fixtures/classes.rb'
+    - 'language/fixtures/private.rb'
+
+# Offense count: 5
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle, SupportedStyles.
+# SupportedStyles: runtime_error, standard_error
+Lint/InheritException:
+  Exclude:
+    - 'core/enumerator/lazy/fixtures/classes.rb'
+    - 'core/exception/fixtures/common.rb'
+    - 'core/module/fixtures/autoload_ex1.rb'
+
+# Offense count: 3
+# Cop supports --auto-correct.
+Lint/LiteralInInterpolation:
+  Exclude:
+    - 'language/defined_spec.rb'
+    - 'language/fixtures/squiggly_heredoc.rb'
+
+# Offense count: 16
+Lint/Loop:
+  Exclude:
+    - 'language/until_spec.rb'
+    - 'language/while_spec.rb'
+
+# Offense count: 8
+# Cop supports --auto-correct.
+Lint/MultipleCompare:
+  Exclude:
+    - 'language/precedence_spec.rb'
+
+# Offense count: 8
+Lint/NestedMethodDefinition:
+  Exclude:
+    - 'language/def_spec.rb'
+
+# Offense count: 12
+Lint/ParenthesesAsGroupedExpression:
+  Exclude:
+    - 'command_line/rubyopt_spec.rb'
+    - 'core/string/fixtures/freeze_magic_comment.rb'
+    - 'language/block_spec.rb'
+    - 'language/fixtures/send.rb'
+    - 'language/method_spec.rb'
+    - 'library/socket/socket/getaddrinfo_spec.rb'
+
+# Offense count: 22
+Lint/RescueException:
+  Exclude:
+    - 'command_line/fixtures/debug_info.rb'
+    - 'core/dir/fileno_spec.rb'
+    - 'core/exception/cause_spec.rb'
+    - 'core/exception/no_method_error_spec.rb'
+    - 'core/kernel/fixtures/autoload_frozen.rb'
+    - 'core/module/autoload_spec.rb'
+    - 'core/mutex/sleep_spec.rb'
+    - 'core/process/euid_spec.rb'
+    - 'core/process/setsid_spec.rb'
+    - 'core/process/uid_spec.rb'
+    - 'core/thread/abort_on_exception_spec.rb'
+    - 'core/thread/shared/exit.rb'
+    - 'language/rescue_spec.rb'
+    - 'library/erb/filename_spec.rb'
+
+# Offense count: 1
+Lint/ScriptPermission:
+  Exclude:
+    - 'command_line/fixtures/bin/launcher.rb'
+
+# Offense count: 10
+Lint/ShadowingOuterLocalVariable:
+  Exclude:
+    - 'core/binding/local_variables_spec.rb'
+    - 'language/block_spec.rb'
+    - 'language/proc_spec.rb'
+
+# Offense count: 2
+# Cop supports --auto-correct.
+Lint/StringConversionInInterpolation:
+  Exclude:
+    - 'core/io/print_spec.rb'
+
+# Offense count: 9
+Lint/UnderscorePrefixedVariableName:
+  Exclude:
+    - 'core/io/pipe_spec.rb'
+    - 'core/io/popen_spec.rb'
+    - 'language/block_spec.rb'
+
+# Offense count: 91
+# Cop supports --auto-correct.
+Lint/UnneededSplatExpansion:
+  Exclude:
+    - 'core/array/element_reference_spec.rb'
+    - 'core/array/unshift_spec.rb'
+    - 'core/enumerable/fixtures/classes.rb'
+    - 'core/enumerable/max_by_spec.rb'
+    - 'core/enumerable/min_by_spec.rb'
+    - 'core/enumerable/minmax_by_spec.rb'
+    - 'core/enumerator/lazy/fixtures/classes.rb'
+    - 'core/file/basename_spec.rb'
+    - 'core/kernel/p_spec.rb'
+    - 'language/array_spec.rb'
+    - 'language/break_spec.rb'
+    - 'language/case_spec.rb'
+    - 'language/next_spec.rb'
+    - 'language/send_spec.rb'
+    - 'language/variables_spec.rb'
+
+# Offense count: 53
+Lint/UnreachableCode:
+  Exclude:
+    - 'core/enumerator/lazy/fixtures/classes.rb'
+    - 'core/kernel/catch_spec.rb'
+    - 'core/kernel/throw_spec.rb'
+    - 'language/break_spec.rb'
+    - 'language/fixtures/break.rb'
+    - 'language/fixtures/break_lambda_toplevel.rb'
+    - 'language/fixtures/break_lambda_toplevel_block.rb'
+    - 'language/fixtures/break_lambda_toplevel_method.rb'
+    - 'language/fixtures/return.rb'
+    - 'language/next_spec.rb'
+    - 'language/return_spec.rb'
+    - 'optional/capi/kernel_spec.rb'
+    - 'shared/kernel/raise.rb'
+
+# Offense count: 9
+# Configuration parameters: ContextCreatingMethods, MethodCreatingMethods.
+Lint/UselessAccessModifier:
+  Exclude:
+    - 'core/module/define_method_spec.rb'
+    - 'core/module/fixtures/classes.rb'
+    - 'core/module/module_function_spec.rb'
+    - 'core/module/private_class_method_spec.rb'
+    - 'core/module/private_spec.rb'
+    - 'core/module/protected_spec.rb'
+    - 'core/module/public_spec.rb'

spec/ruby/.travis.yml

@@ -0,0 +1,34 @@
+sudo: false
+language: ruby
+install:
+  - git clone https://github.com/ruby/mspec.git ../mspec
+script:
+  - if [ -n "$RUBOCOP" ]; then gem install rubocop -v 0.49.1 && rubocop; fi
+  - ../mspec/bin/mspec $MSPEC_OPTS
+matrix:
+  include:
+    - os: osx
+      rvm: 2.4.0
+    - os: linux
+      rvm: 2.4.1
+      env: MSPEC_OPTS="-R2 -ff"
+    - os: linux
+      rvm: 2.2.7
+    - os: linux
+      rvm: 2.3.4
+    - os: linux
+      rvm: 2.4.1
+      env: CHECK_LEAKS=true RUBOCOP=true
+    - os: linux
+      rvm: ruby-head
+  allow_failures:
+    - os: linux
+      rvm: ruby-head
+branches:
+  only:
+    - master
+    - /^try/
+notifications:
+  email:
+    on_success: change
+    on_failure: change

spec/ruby/CONTRIBUTING.md

@@ -0,0 +1,64 @@
+Contributions are much appreciated.
+Please open a pull request or add an issue to discuss what you intend to work on.
+If the pull requests passes the CI and conforms to the existing style of specs, it will be merged.
+
+### File organization
+
+Spec are grouped in 5 separate top-level groups:
+
+* `command_line`: for the ruby executable command-line flags (`-v`, `-e`, etc)
+* `language`: for the language keywords and syntax constructs (`if`, `def`, `A::B`, etc)
+* `core`: for the core methods (`Fixnum#+`, `String#upcase`, no need to require anything)
+* `library`: for the standard libraries methods (`CSV.new`, `YAML.parse`, need to require the stdlib)
+* `optional/capi`: for functions available to the Ruby C-extension API
+
+The exact file for methods is decided by the `#owner` of a method, for instance for `#group_by`:
+```ruby
+> [].method(:group_by)
+=> #<Method: Array(Enumerable)#group_by>
+> [].method(:group_by).owner
+=> Enumerable
+```
+Which should therefore be specified in `core/enumerable/group_by_spec.rb`.
+
+### MkSpec - a tool to generate the spec structure
+
+If you want to create new specs, you should use `mkspec`, part of [MSpec](http://github.com/ruby/mspec).
+
+    $ ../mspec/bin/mkspec -h
+
+#### Creating files for unspecified modules or classes
+
+For instance, to create specs for `forwardable`:
+
+    $ ../mspec/bin/mkspec -b library -rforwardable -c Forwardable
+
+Specify `core` or `library` as the `base`.
+
+#### Finding unspecified core methods
+
+This is very easy, just run the command below in your `spec` directory.
+`ruby` must be a recent version of MRI.
+
+    $ ruby --disable-gem ../mspec/bin/mkspec
+
+You might also want to search for:
+
+    it "needs to be reviewed for spec completeness"
+
+which indicates the file was generated but the method unspecified.
+
+### Guards
+
+Different guards are available as defined by mspec.
+In general, the usage of guards should be minimized as possible.
+
+There are no guards to define implementation-specific behavior because
+the Ruby Spec Suite defines common behavior and not implementation details.
+Use the implementation test suite for these.
+
+If an implementation does not support some feature, simply tag the related specs as failing instead.
+
+### Style
+
+Do not leave any trailing space and respect the existing style.

spec/ruby/LICENSE

@@ -0,0 +1,22 @@
+Copyright (c) 2008 Engine Yard, Inc. All rights reserved.
+
+Permission is hereby granted, free of charge, to any person
+obtaining a copy of this software and associated documentation
+files (the "Software"), to deal in the Software without
+restriction, including without limitation the rights to use,
+copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.

spec/ruby/README.md

@@ -0,0 +1,96 @@
+# The Ruby Spec Suite
+
+[![Build Status](https://travis-ci.org/ruby/spec.svg)](https://travis-ci.org/ruby/spec)
+[![Build Status](https://ci.appveyor.com/api/projects/status/1gs6f399320o44b1?svg=true)](https://ci.appveyor.com/project/eregon/spec-x948i)
+
+The Ruby Spec Suite is a test suite for the behavior of the Ruby programming language.
+
+It is not a standardized specification like the ISO one, and does not aim to become one.
+Instead, it is a practical tool to describe and test the behavior of Ruby with code.
+
+Every example code has a textual description, which presents several advantages:
+
+* It is easier to understand the intent of the author
+* It documents how recent versions of Ruby should behave
+* It helps Ruby implementations to agree on a common behavior
+
+The specs are written with syntax similar to RSpec 2.
+They are run with MSpec, the purpose-built framework for running the Ruby Spec Suite.
+For more information, see the [MSpec](http://github.com/ruby/mspec) project.
+
+The specs describe the [language syntax](language/), the [core library](core/), the [standard library](library/), the [C API for extensions](optional/capi) and the [command line flags](command_line/).
+The language specs are grouped by keyword while the core and standard library specs are grouped by class and method.
+
+ruby/spec is known to be tested in these implementations for every commit:
+* [MRI](http://rubyci.org/) on 30 platforms and 4 versions
+* [JRuby](https://github.com/jruby/jruby/tree/master/spec/ruby) on Travis for both 1.7 and 9.x
+* [TruffleRuby](https://github.com/graalvm/truffleruby) on Travis
+* [Opal](https://github.com/opal/opal/tree/master/spec) on Travis
+
+ruby/spec describes the behavior of Ruby 2.2 and more recent Ruby versions.
+More precisely, every latest stable MRI release [passes](https://rubyci.org/) all specs of ruby/spec
+(latest 2.2.x, 2.3.x, 2.4.x, etc).
+
+For older specs try these commits:
+* Ruby 2.0.0-p647 - [Suite](https://github.com/ruby/spec/commit/245862558761d5abc676843ef74f86c9bcc8ea8d) using [MSpec](https://github.com/ruby/mspec/commit/f90efa068791064f955de7a843e96e2d7d3041c2) (may encounter 2 failures)
+* Ruby 2.1.9 - [Suite](https://github.com/ruby/spec/commit/f029e65241374386077ac500add557ae65069b55) using [MSpec](https://github.com/ruby/mspec/commit/55568ea3918c6380e64db8c567d732fa5781efed)
+
+### Running the specs
+
+First, clone this repository:
+
+    $ git clone https://github.com/ruby/spec.git
+
+Then move to it:
+
+    $ cd spec
+
+Clone [MSpec](http://github.com/ruby/mspec):
+
+    $ git clone https://github.com/ruby/mspec.git ../mspec
+
+And run the spec suite:
+
+    $ ../mspec/bin/mspec
+
+This will execute all the specs using the executable named `ruby` on your current PATH.
+
+### Running Specs with a Specific Ruby Implementation
+
+Use the `-t` option to specify the Ruby implementation with which to run the specs.
+The argument may be a full path to the Ruby binary.
+
+    $ ../mspec/bin/mspec -t /path/to/some/bin/ruby
+
+### Running Selected Specs
+
+To run a single spec file, pass the filename to `mspec`:
+
+    $ ../mspec/bin/mspec core/kernel/kind_of_spec.rb
+
+You can also pass a directory, in which case all specs in that directories will be run:
+
+    $ ../mspec/bin/mspec core/kernel
+
+Finally, you can also run them per group as defined in `default.mspec`.
+The following command will run all language specs:
+
+    $ ../mspec/bin/mspec :language
+
+In similar fashion, the following commands run the respective specs:
+
+    $ ../mspec/bin/mspec :core
+    $ ../mspec/bin/mspec :library
+    $ ../mspec/bin/mspec :capi
+
+### Contributing
+
+See [CONTRIBUTING.md](https://github.com/ruby/spec/blob/master/CONTRIBUTING.md).
+
+### History and RubySpec
+
+This project was originally born from [Rubinius](https://github.com/rubinius/rubinius) tests being converted to the spec style.
+These specs were later extracted to their own project, RubySpec, with a specific vision and principles.
+At the end of 2014, Brian Shirai, the creator of RubySpec, decided to [end RubySpec](http://rubinius.com/2014/12/31/matz-s-ruby-developers-don-t-use-rubyspec/).
+A couple months later, the different repositories were merged and [the project was revived](http://eregon.github.io/rubyspec/2015/07/29/rubyspec-is-reborn.html).
+On 12 January 2016, the name was changed to "The Ruby Spec Suite" for clarity and to let the RubySpec ideology rest in peace.

spec/ruby/TODO

@@ -0,0 +1,8 @@
+* Decide a way to test methods that are only visible given a specific
+  command-line option. For example, Kernel#gsub with -n/-p on 1.9.
+* Look at automating discovery of guarded bugs which have been fixed.
+* Use mocks for all Math functions that coerce with #to_f; currently a fixture
+  is used.
+* investigate slow specs (run with -fp) and make them faster.
+* restore some caller specs from 642bf529
+* restore refinements specs and update. See 56c5528f and f20a62e8.

spec/ruby/appveyor.yml

@@ -0,0 +1,19 @@
+---
+version: "{build}"
+clone_depth: 5
+environment:
+  matrix:
+    - RUBY_VERSION: 23-x64
+install:
+  - SET PATH=C:\Ruby%RUBY_VERSION%\bin;%PATH%
+  - ruby --version
+  - call "C:\Ruby23-x64\DevKit\devkitvars.bat"
+  - git clone https://github.com/ruby/mspec.git ../mspec
+build: off
+test_script:
+  - SET CHECK_LEAKS=true
+  - ../mspec/bin/mspec -ff
+branches:
+  only:
+    - master
+    - /^try/

spec/ruby/command_line/dash_a_spec.rb

@@ -0,0 +1,17 @@
+describe "The -a command line option" do
+  before :each do
+    @names  = fixture __FILE__, "full_names.txt"
+  end
+
+  it "runs the code in loop conditional on Kernel.gets()" do
+    ruby_exe("puts $F.last", options: "-n -a", escape: true,
+                             args: " < #{@names}").should ==
+      "jones\nfield\ngrey\n"
+  end
+
+  it "sets $-a" do
+    ruby_exe("puts $-a", options: "-n -a", escape: true,
+                         args: " < #{@names}").should ==
+      "true\ntrue\ntrue\n"
+  end
+end

spec/ruby/command_line/dash_c_spec.rb

@@ -0,0 +1,13 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe "The -c command line option" do
+  it "checks syntax in given file" do
+    ruby_exe(nil, args: "-c #{__FILE__}").chomp.should == "Syntax OK"
+  end
+
+  it "checks syntax in -e strings" do
+    ruby_exe(nil, args: "-c -e 'puts 1' -e 'hello world'").chomp.should == "Syntax OK"
+  end
+
+  #Also needs spec for reading from STDIN
+end

spec/ruby/command_line/dash_d_spec.rb

@@ -0,0 +1,22 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe "The -d command line option" do
+  before :each do
+    @script = fixture __FILE__, "debug.rb"
+  end
+
+  it "sets $DEBUG to true" do
+    ruby_exe(@script, options: "-d",
+                      args: "0 2> #{File::NULL}").chomp.should == "$DEBUG true"
+  end
+
+  it "sets $VERBOSE to true" do
+    ruby_exe(@script, options: "-d",
+                      args: "1 2> #{File::NULL}").chomp.should == "$VERBOSE true"
+  end
+
+  it "sets $-d to true" do
+    ruby_exe(@script, options: "-d",
+                      args: "2 2> #{File::NULL}").chomp.should == "$-d true"
+  end
+end

spec/ruby/command_line/dash_e_spec.rb

@@ -0,0 +1,41 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe "The -e command line option" do
+  it "evaluates the given string" do
+    ruby_exe("puts 'foo'").chomp.should == "foo"
+  end
+
+  it "joins multiple strings with newlines" do
+    ruby_exe(nil, args: %Q{-e "puts 'hello" -e "world'" 2>&1}).chomp.should == "hello\nworld"
+  end
+
+  it "uses 'main' as self" do
+    ruby_exe("puts self", escape: false).chomp.should == "main"
+  end
+
+  it "uses '-e' as file" do
+    ruby_exe("puts __FILE__", escape: false).chomp.should == "-e"
+  end
+
+  it "uses '-e' in $0" do
+    system(*ruby_exe, '-e', 'exit $0 == "-e"').should == true
+  end
+
+  #needs to test return => LocalJumpError
+
+  describe "with -n and a Fixnum range" do
+    before :each do
+      @script = "-ne 'print if %s' #{fixture(__FILE__, "conditional_range.txt")}"
+    end
+
+    it "mimics an awk conditional by comparing an inclusive-end range with $." do
+      ruby_exe(nil, args: (@script % "2..3")).should == "2\n3\n"
+      ruby_exe(nil, args: (@script % "2..2")).should == "2\n"
+    end
+
+    it "mimics a sed conditional by comparing an exclusive-end range with $." do
+      ruby_exe(nil, args: (@script % "2...3")).should == "2\n3\n"
+      ruby_exe(nil, args: (@script % "2...2")).should == "2\n3\n4\n5\n"
+    end
+  end
+end

spec/ruby/command_line/dash_n_spec.rb

@@ -0,0 +1,34 @@
+describe "The -n command line option" do
+  before :each do
+    @names  = fixture __FILE__, "names.txt"
+  end
+
+  it "runs the code in loop conditional on Kernel.gets()" do
+    ruby_exe("puts $_", options: "-n", escape: true,
+                        args: " < #{@names}").should ==
+      "alice\nbob\njames\n"
+  end
+
+  it "only evaluates BEGIN blocks once" do
+    ruby_exe("BEGIN { puts \"hi\" }; puts $_", options: "-n", escape: true,
+                                               args: " < #{@names}").should ==
+      "hi\nalice\nbob\njames\n"
+  end
+
+  it "only evaluates END blocks once" do
+    ruby_exe("puts $_; END {puts \"bye\"}", options: "-n", escape: true,
+                                            args: " < #{@names}").should ==
+      "alice\nbob\njames\nbye\n"
+  end
+
+  it "allows summing over a whole file" do
+    script = <<-script
+    BEGIN { $total = 0 }
+    $total += 1
+    END { puts $total }
+    script
+    ruby_exe(script, options: "-n", escape: true,
+                     args: " < #{@names}").should ==
+      "3\n"
+  end
+end

spec/ruby/command_line/dash_p_spec.rb

@@ -0,0 +1,17 @@
+describe "The -p command line option" do
+  before :each do
+    @names  = fixture __FILE__, "names.txt"
+  end
+
+  it "runs the code in loop conditional on Kernel.gets() and prints $_" do
+    ruby_exe("$_ = $_.upcase", options: "-p", escape: true,
+                               args: " < #{@names}").should ==
+      "ALICE\nBOB\nJAMES\n"
+  end
+
+  it "sets $-p" do
+    ruby_exe("$_ = $-p", options: "-p", escape: true,
+                         args: " < #{@names}").should ==
+      "truetruetrue"
+  end
+end

spec/ruby/command_line/dash_r_spec.rb

@@ -0,0 +1,13 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe "The -r command line option" do
+  before :each do
+    @script = fixture __FILE__, "require.rb"
+    @test_file = fixture __FILE__, "test_file"
+  end
+
+  it "requires the specified file" do
+    result = ruby_exe(@script, options: "-r #{@test_file}")
+    result.should include(@test_file + ".rb")
+  end
+end

spec/ruby/command_line/dash_s_spec.rb

@@ -0,0 +1,52 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe "The -s command line option" do
+  describe "when using -- to stop parsing" do
+    it "sets the value to true without an explicit value" do
+      ruby_exe(nil, options: "-s -e 'p $n'",
+                    args: "-- -n").chomp.should == "true"
+    end
+
+    it "parses single letter args into globals" do
+      ruby_exe(nil, options: "-s -e 'puts $n'",
+                    args: "-- -n=blah").chomp.should == "blah"
+    end
+
+    it "parses long args into globals" do
+      ruby_exe(nil, options: "-s -e 'puts $_name'",
+                    args: "-- --name=blah").chomp.should == "blah"
+    end
+
+    it "converts extra dashes into underscores" do
+      ruby_exe(nil, options: "-s -e 'puts $___name__test__'",
+                    args: "-- ----name--test--=blah").chomp.should == "blah"
+    end
+  end
+
+  describe "when running a script" do
+    before :all do
+      @script = fixture __FILE__, "dash_s_script.rb"
+    end
+
+    it "sets the value to true without an explicit value" do
+      ruby_exe(@script, options: "-s",
+                        args: "-n 0").chomp.should == "true"
+    end
+
+    it "parses single letter args into globals" do
+      ruby_exe(@script, options: "-s",
+                        args: "-n=blah 1").chomp.should == "blah"
+    end
+
+    it "parses long args into globals" do
+      ruby_exe(@script, options: "-s",
+                        args: "--name=blah 2").chomp.should == "blah"
+    end
+
+    it "converts extra dashes into underscores" do
+      ruby_exe(@script, options: "-s",
+                        args: "----name--test--=blah 3").chomp.should == "blah"
+    end
+
+  end
+end

spec/ruby/command_line/dash_upper_c_spec.rb

@@ -0,0 +1,18 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe 'The -C command line option' do
+  before :all do
+    @script  = fixture(__FILE__, 'dash_upper_c_script.rb')
+    @tempdir = File.dirname(@script)
+  end
+
+  it 'changes the PWD when using a file' do
+    output = ruby_exe(@script, options: "-C #{@tempdir}")
+    output.should == @tempdir
+  end
+
+  it 'changes the PWD when using -e' do
+    output = ruby_exe(nil, options: "-C #{@tempdir} -e 'print Dir.pwd'")
+    output.should == @tempdir
+  end
+end

spec/ruby/command_line/dash_upper_e_spec.rb

@@ -0,0 +1,7 @@
+describe "ruby -E" do
+  it "raises a RuntimeError if used with -U" do
+    ruby_exe("p 1",
+             options: '-Eascii:ascii -U',
+             args: '2>&1').should =~ /RuntimeError/
+  end
+end

spec/ruby/command_line/dash_upper_f_spec.rb

@@ -0,0 +1,11 @@
+describe "the -F command line option" do
+  before :each do
+    @passwd  = fixture __FILE__, "passwd_file.txt"
+  end
+
+  it "specifies the field separator pattern for -a" do
+    ruby_exe("puts $F[0]", options: "-naF:", escape: true,
+                           args: " < #{@passwd}").should ==
+      "nobody\nroot\ndaemon\n"
+  end
+end

spec/ruby/command_line/dash_upper_i_spec.rb

@@ -0,0 +1,11 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe "The -I command line option" do
+  before :each do
+    @script = fixture __FILE__, "loadpath.rb"
+  end
+
+  it "adds the path to the load path ($:)" do
+    ruby_exe(@script, options: "-I fixtures").should include("fixtures")
+  end
+end

spec/ruby/command_line/dash_upper_k_spec.rb

@@ -0,0 +1,33 @@
+describe 'The -K command line option sets __ENCODING__' do
+  it "to Encoding::ASCII_8BIT with -Ka" do
+    ruby_exe("print __ENCODING__", options: '-Ka').should == Encoding::ASCII_8BIT.to_s
+  end
+
+  it "to Encoding::ASCII_8BIT with -KA" do
+    ruby_exe("print __ENCODING__", options: '-KA').should == Encoding::ASCII_8BIT.to_s
+  end
+
+  it "to Encoding::EUC_JP with -Ke" do
+    ruby_exe("print __ENCODING__", options: '-Ke').should == Encoding::EUC_JP.to_s
+  end
+
+  it "to Encoding::EUC_JP with -KE" do
+    ruby_exe("print __ENCODING__", options: '-KE').should == Encoding::EUC_JP.to_s
+  end
+
+  it "to Encoding::UTF_8 with -Ku" do
+    ruby_exe("print __ENCODING__", options: '-Ku').should == Encoding::UTF_8.to_s
+  end
+
+  it "to Encoding::UTF_8 with -KU" do
+    ruby_exe("print __ENCODING__", options: '-KU').should == Encoding::UTF_8.to_s
+  end
+
+  it "to Encoding::Windows_31J with -Ks" do
+    ruby_exe("print __ENCODING__", options: '-Ks').should == Encoding::Windows_31J.to_s
+  end
+
+  it "to Encoding::Windows_31J with -KS" do
+    ruby_exe("print __ENCODING__", options: '-KS').should == Encoding::Windows_31J.to_s
+  end
+end

spec/ruby/command_line/dash_upper_s_spec.rb

@@ -0,0 +1,29 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe 'The -S command line option' do
+  before :each do
+    @path = [ENV['PATH'], fixture(__FILE__, "bin")].join(':')
+  end
+
+  platform_is_not :windows do
+    # On VirtualBox shared directory (vboxsf) all files are world writable
+    # and MRI shows warning when including world writable path in ENV['PATH'].
+    # This is why we are using /success$/ matching in the following cases.
+
+    it "runs launcher found in PATH, but only code after the first /\#!.*ruby.*/-ish line in target file" do
+      result = ruby_exe(nil, options: '-S hybrid_launcher.sh', env: { 'PATH' => @path }, args: '2>&1')
+      result.should =~ /success$/
+    end
+
+    it "runs launcher found in PATH" do
+      result = ruby_exe(nil, options: '-S launcher.rb', env: { 'PATH' => @path }, args: '2>&1')
+      result.should =~ /success$/
+    end
+
+    it "runs launcher found in PATH and sets the exit status to 1 if it fails" do
+      result = ruby_exe(nil, options: '-S dash_s_fail', env: { 'PATH' => @path }, args: '2>&1')
+      result.should =~ /\bdie\b/
+      $?.exitstatus.should == 1
+    end
+  end
+end

spec/ruby/command_line/dash_upper_u_spec.rb

@@ -0,0 +1,41 @@
+describe "ruby -U" do
+  it "sets Encoding.default_internal to UTF-8" do
+     ruby_exe('print Encoding.default_internal.name',
+              options: '-U').should == 'UTF-8'
+  end
+
+  it "does nothing different if specified multiple times" do
+     ruby_exe('print Encoding.default_internal.name',
+              options: '-U -U').should == 'UTF-8'
+  end
+
+  it "is overruled by Encoding.default_internal=" do
+     ruby_exe('Encoding.default_internal="ascii"; print Encoding.default_internal.name',
+              options: '-U').should == 'US-ASCII'
+  end
+
+  it "does not affect the default external encoding" do
+     ruby_exe('Encoding.default_external="ascii"; print Encoding.default_external.name',
+              options: '-U').should == 'US-ASCII'
+  end
+
+  it "does not affect the source encoding" do
+     ruby_exe("print __ENCODING__.name",
+              options: '-U -KE').should == 'EUC-JP'
+     ruby_exe("print __ENCODING__.name",
+              options: '-KE -U').should == 'EUC-JP'
+  end
+
+  # I assume IO redirection will break on Windows...
+  it "raises a RuntimeError if used with -Eext:int" do
+    ruby_exe("p 1",
+             options: '-U -Eascii:ascii',
+             args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError if used with -E:int" do
+    ruby_exe("p 1",
+             options: '-U -E:ascii',
+             args: '2>&1').should =~ /RuntimeError/
+  end
+end

spec/ruby/command_line/dash_upper_w_spec.rb

@@ -0,0 +1,20 @@
+require File.expand_path('../../spec_helper', __FILE__)
+require File.expand_path('../shared/verbose', __FILE__)
+
+describe "The -W command line option" do
+  before :each do
+    @script = fixture __FILE__, "verbose.rb"
+  end
+
+  it "with 0 sets $VERBOSE to nil" do
+    ruby_exe(@script, options: "-W0").chomp.should == "nil"
+  end
+
+  it "with 1 sets $VERBOSE to false" do
+    ruby_exe(@script, options: "-W1").chomp.should == "false"
+  end
+end
+
+describe "The -W command line option with 2" do
+  it_behaves_like :command_line_verbose, "-W2"
+end

spec/ruby/command_line/dash_v_spec.rb

@@ -0,0 +1,13 @@
+require File.expand_path('../../spec_helper', __FILE__)
+require File.expand_path('../shared/verbose', __FILE__)
+
+describe "The -v command line option" do
+  it_behaves_like :command_line_verbose, "-v"
+
+  describe "when used alone" do
+    it "prints version and ends" do
+      version = ruby_exe(nil, args: '--version')
+      ruby_exe(nil, args: '-v').should == version
+    end
+  end
+end

spec/ruby/command_line/dash_w_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../spec_helper', __FILE__)
+require File.expand_path('../shared/verbose', __FILE__)
+
+describe "The -w command line option" do
+  it_behaves_like :command_line_verbose, "-w"
+end

spec/ruby/command_line/dash_x_spec.rb

@@ -0,0 +1,21 @@
+describe "The -x command line option" do
+  it "runs code after the first /\#!.*ruby.*/-ish line in target file" do
+    embedded_ruby = fixture __FILE__, "bin/embedded_ruby.txt"
+    result = ruby_exe(embedded_ruby, options: '-x')
+    result.should == "success\n"
+  end
+
+  it "fails when /\#!.*ruby.*/-ish line in target file is not found" do
+    bad_embedded_ruby = fixture __FILE__, "bin/bad_embedded_ruby.txt"
+    result = ruby_exe(bad_embedded_ruby, options: '-x', args: '2>&1')
+    result.should include "no Ruby script found in input"
+  end
+
+  it "behaves as -x was set when non-ruby shebang is encountered on first line" do
+    embedded_ruby = fixture __FILE__, "bin/hybrid_launcher.sh"
+    result = ruby_exe(embedded_ruby)
+    result.should == "success\n"
+  end
+
+  it "needs to be reviewed for spec completeness"
+end

spec/ruby/command_line/error_message_spec.rb

@@ -0,0 +1,11 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe "The error message caused by an exception" do
+  it "is not printed to stdout" do
+    out = ruby_exe("this_does_not_exist", args: "2> #{File::NULL}")
+    out.chomp.empty?.should == true
+
+    out = ruby_exe("end #syntax error", args: "2> #{File::NULL}")
+    out.chomp.empty?.should == true
+  end
+end

spec/ruby/command_line/fixtures/bad_syntax.rb

@@ -0,0 +1 @@
+f {

spec/ruby/command_line/fixtures/bin/bad_embedded_ruby.txt

@@ -0,0 +1,3 @@
+@@@This line is not value Ruby
+#!rub_y
+puts 'success'

spec/ruby/command_line/fixtures/bin/dash_s_fail

@@ -0,0 +1 @@
+raise 'die'

spec/ruby/command_line/fixtures/bin/embedded_ruby.txt

@@ -0,0 +1,3 @@
+@@@This line is not value Ruby
+#!ruby
+puts 'success'

spec/ruby/command_line/fixtures/bin/hybrid_launcher.sh

@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+exec somehow this file
+#!ruby
+puts 'success'

spec/ruby/command_line/fixtures/bin/launcher.rb

@@ -0,0 +1,2 @@
+#!ruby
+puts 'success'

spec/ruby/command_line/fixtures/conditional_range.txt

@@ -0,0 +1,5 @@
+1
+2
+3
+4
+5

spec/ruby/command_line/fixtures/dash_s_script.rb

@@ -0,0 +1,12 @@
+which = ARGV.shift.to_i
+
+case which
+when 0
+  p $n
+when 1
+  puts $n
+when 2
+  puts $_name
+when 3
+  puts $___name__test__
+end

spec/ruby/command_line/fixtures/dash_upper_c_script.rb

@@ -0,0 +1 @@
+print Dir.pwd

spec/ruby/command_line/fixtures/debug.rb

@@ -0,0 +1,10 @@
+which = ARGV.first.to_i
+
+case which
+when 0
+  puts "$DEBUG #{$DEBUG}"
+when 1
+  puts "$VERBOSE #{$VERBOSE}"
+when 2
+  puts "$-d #{$-d}"
+end

spec/ruby/command_line/fixtures/debug_info.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+a = 'string'
+b = a
+c = b
+d = c
+e = d
+begin
+  a << 'new part'
+rescue Exception => e
+  print e.message
+end

spec/ruby/command_line/fixtures/freeze_flag_across_files.rb

@@ -0,0 +1,3 @@
+require_relative 'freeze_flag_required'
+
+p "abc".object_id == $second_literal_id

spec/ruby/command_line/fixtures/freeze_flag_across_files_diff_enc.rb

@@ -0,0 +1,3 @@
+require_relative 'freeze_flag_required_diff_enc'
+
+p "abc".object_id != $second_literal_id

spec/ruby/command_line/fixtures/freeze_flag_one_literal.rb

@@ -0,0 +1,2 @@
+ids = Array.new(2) { "abc".object_id }
+p ids.first == ids.last

spec/ruby/command_line/fixtures/freeze_flag_required.rb

@@ -0,0 +1 @@
+$second_literal_id = "abc".object_id

spec/ruby/command_line/fixtures/freeze_flag_two_literals.rb

@@ -0,0 +1 @@
+p "abc".object_id == "abc".object_id

spec/ruby/command_line/fixtures/full_names.txt

@@ -0,0 +1,3 @@
+alice jones
+bob field
+james grey

spec/ruby/command_line/fixtures/loadpath.rb

@@ -0,0 +1 @@
+puts $:

spec/ruby/command_line/fixtures/names.txt

@@ -0,0 +1,3 @@
+alice
+bob
+james

spec/ruby/command_line/fixtures/passwd_file.txt

@@ -0,0 +1,3 @@
+nobody:*:-2:-2:Unprivileged User:/var/empty:/usr/bin/false
+root:*:0:0:System Administrator:/var/root:/bin/sh
+daemon:*:1:1:System Services:/var/root:/usr/bin/false

spec/ruby/command_line/fixtures/require.rb

@@ -0,0 +1 @@
+puts $"

spec/ruby/command_line/fixtures/rubyopt.rb

@@ -0,0 +1 @@
+puts "rubyopt.rb required"

spec/ruby/command_line/fixtures/test_file.rb

@@ -0,0 +1 @@
+"test file"

spec/ruby/command_line/fixtures/verbose.rb

@@ -0,0 +1 @@
+puts $VERBOSE.inspect

spec/ruby/command_line/frozen_strings_spec.rb

@@ -0,0 +1,30 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+ruby_version_is "2.3" do
+  describe "The --enable-frozen-string-literal flag causes string literals to" do
+
+    it "produce the same object each time" do
+      ruby_exe(fixture(__FILE__, "freeze_flag_one_literal.rb"), options: "--enable-frozen-string-literal").chomp.should == "true"
+    end
+
+    it "produce the same object for literals with the same content" do
+      ruby_exe(fixture(__FILE__, "freeze_flag_two_literals.rb"), options: "--enable-frozen-string-literal").chomp.should == "true"
+    end
+
+    it "produce the same object for literals with the same content in different files" do
+      ruby_exe(fixture(__FILE__, "freeze_flag_across_files.rb"), options: "--enable-frozen-string-literal").chomp.should == "true"
+    end
+
+    it "produce different objects for literals with the same content in different files if they have different encodings" do
+      ruby_exe(fixture(__FILE__, "freeze_flag_across_files_diff_enc.rb"), options: "--enable-frozen-string-literal").chomp.should == "true"
+    end
+  end
+
+  describe "The --debug flag produces" do
+    it "debugging info on attempted frozen string modification" do
+      error_str = ruby_exe(fixture(__FILE__, 'debug_info.rb'), options: '--debug',  args: "2>&1")
+      error_str.should include("can't modify frozen String, created at ")
+      error_str.should include("command_line/fixtures/debug_info.rb:2")
+    end
+  end
+end

spec/ruby/command_line/rubyopt_spec.rb

@@ -0,0 +1,160 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe "Processing RUBYOPT" do
+  before (:each) do
+    @rubyopt, ENV["RUBYOPT"] = ENV["RUBYOPT"], nil
+  end
+
+  after (:each) do
+    ENV["RUBYOPT"] = @rubyopt
+  end
+
+  it "adds the -I path to $LOAD_PATH" do
+    ENV["RUBYOPT"] = "-Ioptrubyspecincl"
+    result = ruby_exe("puts $LOAD_PATH.grep(/byspecin/)", escape: true)
+    result.chomp[-15..-1].should == "optrubyspecincl"
+  end
+
+  it "sets $DEBUG to true for '-d'" do
+    ENV["RUBYOPT"] = '-d'
+    command = %[puts "value of $DEBUG is \#{$DEBUG}"]
+    result = ruby_exe(command, escape: true, args: "2>&1")
+    result.should =~ /value of \$DEBUG is true/
+  end
+
+  it "prints the version number for '-v'" do
+    ENV["RUBYOPT"] = '-v'
+    ruby_exe("")[/\A.*/].should == RUBY_DESCRIPTION
+  end
+
+  it "sets $VERBOSE to true for '-w'" do
+    ENV["RUBYOPT"] = '-w'
+    ruby_exe("p $VERBOSE", escape: true).chomp.should == "true"
+  end
+
+  it "sets $VERBOSE to true for '-W'" do
+    ENV["RUBYOPT"] = '-W'
+    ruby_exe("p $VERBOSE", escape: true).chomp.should == "true"
+  end
+
+  it "sets $VERBOSE to nil for '-W0'" do
+    ENV["RUBYOPT"] = '-W0'
+    ruby_exe("p $VERBOSE", escape: true).chomp.should == "nil"
+  end
+
+  it "sets $VERBOSE to false for '-W1'" do
+    ENV["RUBYOPT"] = '-W1'
+    ruby_exe("p $VERBOSE", escape: true).chomp.should == "false"
+  end
+
+  it "sets $VERBOSE to true for '-W2'" do
+    ENV["RUBYOPT"] = '-W2'
+    ruby_exe("p $VERBOSE", escape: true).chomp.should == "true"
+  end
+
+  it "requires the file for '-r'" do
+    f = fixture __FILE__, "rubyopt"
+    ENV["RUBYOPT"] = "-r#{f}"
+    ruby_exe("0", args: '2>&1').should =~ /^rubyopt.rb required/
+  end
+
+  it "raises a RuntimeError for '-a'" do
+    ENV["RUBYOPT"] = '-a'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-p'" do
+    ENV["RUBYOPT"] = '-p'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-n'" do
+    ENV["RUBYOPT"] = '-n'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-y'" do
+    ENV["RUBYOPT"] = '-y'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-c'" do
+    ENV["RUBYOPT"] = '-c'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-s'" do
+    ENV["RUBYOPT"] = '-s'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-h'" do
+    ENV["RUBYOPT"] = '-h'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '--help'" do
+    ENV["RUBYOPT"] = '--help'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-l'" do
+    ENV["RUBYOPT"] = '-l'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-S'" do
+    ENV["RUBYOPT"] = '-S irb'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-e'" do
+    ENV["RUBYOPT"] = '-e0'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-i'" do
+    ENV["RUBYOPT"] = '-i.bak'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-x'" do
+    ENV["RUBYOPT"] = '-x'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-C'" do
+    ENV["RUBYOPT"] = '-C'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-X'" do
+    ENV["RUBYOPT"] = '-X.'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-F'" do
+    ENV["RUBYOPT"] = '-F'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '-0'" do
+    ENV["RUBYOPT"] = '-0'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '--copyright'" do
+    ENV["RUBYOPT"] = '--copyright'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '--version'" do
+    ENV["RUBYOPT"] = '--version'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+
+  it "raises a RuntimeError for '--yydebug'" do
+    ENV["RUBYOPT"] = '--yydebug'
+    ruby_exe("", args: '2>&1').should =~ /RuntimeError/
+  end
+end

spec/ruby/command_line/shared/verbose.rb

@@ -0,0 +1,9 @@
+describe :command_line_verbose, shared: true do
+  before :each do
+    @script = fixture __FILE__, "verbose.rb"
+  end
+
+  it "sets $VERBOSE to true" do
+    ruby_exe(@script, options: @method).chomp.split.last.should == "true"
+  end
+end

spec/ruby/command_line/syntax_error_spec.rb

@@ -0,0 +1,13 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe "The interpreter" do
+  it "prints an error when given a file with invalid syntax" do
+    out = ruby_exe(fixture(__FILE__, "bad_syntax.rb"), args: "2>&1")
+    out.should include "syntax error"
+  end
+
+  it "prints an error when given code via -e with invalid syntax" do
+    out = ruby_exe(nil, args: "-e 'a{' 2>&1")
+    out.should include "syntax error"
+  end
+end

spec/ruby/core/argf/argf_spec.rb

@@ -0,0 +1,11 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "ARGF" do
+  it "is extended by the Enumerable module" do
+    ARGF.should be_kind_of(Enumerable)
+  end
+
+  it "is an instance of ARGF.class" do
+    ARGF.should be_an_instance_of(ARGF.class)
+  end
+end

spec/ruby/core/argf/argv_spec.rb

@@ -0,0 +1,19 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "ARGF.argv" do
+  before :each do
+    @file1    = fixture __FILE__, "file1.txt"
+    @file2    = fixture __FILE__, "file2.txt"
+  end
+
+  it "returns ARGV for the initial ARGF" do
+    ARGF.argv.should equal ARGV
+  end
+
+  it "returns the remaining arguments to treat" do
+    argf [@file1, @file2] do
+      # @file1 is stored in current file
+      @argf.argv.should == [@file2]
+    end
+  end
+end

spec/ruby/core/argf/binmode_spec.rb

@@ -0,0 +1,43 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "ARGF.binmode" do
+  before :each do
+    @file1    = fixture __FILE__, "file1.txt"
+    @file2    = fixture __FILE__, "file2.txt"
+    @bin_file = fixture __FILE__, "bin_file.txt"
+  end
+
+  it "returns self" do
+    argf [@bin_file] do
+      @argf.binmode.should equal @argf
+    end
+  end
+
+  platform_is :windows do
+    it "puts reading into binmode" do
+      argf [@bin_file, @bin_file] do
+        @argf.gets.should == "test\n"
+        @argf.binmode
+        @argf.gets.should == "test\r\n"
+      end
+    end
+
+    it "puts alls subsequent stream reading through ARGF into binmode" do
+      argf [@bin_file, @bin_file] do
+        @argf.binmode
+        @argf.gets.should == "test\r\n"
+        @argf.gets.should == "test\r\n"
+      end
+    end
+  end
+
+  it "sets the file's encoding to ASCII-8BIT" do
+    argf [@bin_file, @file1] do
+      @argf.binmode
+      @argf.binmode?.should == true
+      @argf.gets.encoding.should == Encoding::ASCII_8BIT
+      @argf.skip
+      @argf.read.encoding.should == Encoding::ASCII_8BIT
+    end
+  end
+end

spec/ruby/core/argf/bytes_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/each_byte', __FILE__)
+
+describe "ARGF.bytes" do
+  it_behaves_like :argf_each_byte, :bytes
+end

spec/ruby/core/argf/chars_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/each_char', __FILE__)
+
+describe "ARGF.chars" do
+  it_behaves_like :argf_each_char, :chars
+end

spec/ruby/core/argf/close_spec.rb

@@ -0,0 +1,46 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "ARGF.close" do
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+    @file2_name = fixture __FILE__, "file2.txt"
+  end
+
+  it "closes the current open stream" do
+    argf [@file1_name, @file2_name] do
+      io = @argf.to_io
+      @argf.close
+      io.closed?.should be_true
+    end
+  end
+
+  it "returns self" do
+    argf [@file1_name, @file2_name] do
+      @argf.close.should equal(@argf)
+    end
+  end
+
+  ruby_version_is ""..."2.3" do
+    it "raises an IOError if called on a closed stream" do
+      argf [@file1_name] do
+        lambda { @argf.close }.should_not raise_error
+        lambda { @argf.close }.should raise_error(IOError)
+      end
+    end
+  end
+
+  ruby_version_is "2.3" do
+    it "doesn't raise an IOError if called on a closed stream" do
+      argf [@file1_name] do
+        lambda { @argf.close }.should_not raise_error
+        lambda { @argf.close }.should_not raise_error
+      end
+    end
+  end
+end
+
+describe "ARGF.close" do
+  it "does not close STDIN" do
+    ruby_exe("ARGV.replace(['-']); ARGF.close; print ARGF.closed?").should == "false"
+  end
+end

spec/ruby/core/argf/closed_spec.rb

@@ -0,0 +1,18 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "ARGF.closed?" do
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+    @file2_name = fixture __FILE__, "file2.txt"
+  end
+
+  it "returns true if the current stream has been closed" do
+    argf [@file1_name, @file2_name] do
+      stream = @argf.to_io
+      stream.close
+
+      @argf.closed?.should be_true
+      stream.reopen(@argf.filename, 'r')
+    end
+  end
+end

spec/ruby/core/argf/codepoints_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/each_codepoint', __FILE__)
+
+describe "ARGF.codepoints" do
+  it_behaves_like :argf_each_codepoint, :codepoints
+end

spec/ruby/core/argf/each_byte_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/each_byte', __FILE__)
+
+describe "ARGF.each_byte" do
+  it_behaves_like :argf_each_byte, :each_byte
+end

spec/ruby/core/argf/each_char_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/each_char', __FILE__)
+
+describe "ARGF.each_char" do
+  it_behaves_like :argf_each_char, :each_char
+end

spec/ruby/core/argf/each_codepoint_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/each_codepoint', __FILE__)
+
+describe "ARGF.each_codepoint" do
+  it_behaves_like :argf_each_codepoint, :each_codepoint
+end

spec/ruby/core/argf/each_line_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/each_line', __FILE__)
+
+describe "ARGF.each_line" do
+  it_behaves_like :argf_each_line, :each_line
+end

spec/ruby/core/argf/each_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/each_line', __FILE__)
+
+describe "ARGF.each" do
+  it_behaves_like :argf_each_line, :each
+end

spec/ruby/core/argf/eof_spec.rb

@@ -0,0 +1,10 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/eof', __FILE__)
+
+describe "ARGF.eof" do
+  it_behaves_like :argf_eof, :eof
+end
+
+describe "ARGF.eof?" do
+  it_behaves_like :argf_eof, :eof?
+end

spec/ruby/core/argf/file_spec.rb

@@ -0,0 +1,21 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "ARGF.file" do
+  before :each do
+    @file1 = fixture __FILE__, "file1.txt"
+    @file2 = fixture __FILE__, "file2.txt"
+  end
+
+  # NOTE: this test assumes that fixtures files have two lines each
+  it "returns the current file object on each file" do
+    argf [@file1, @file2] do
+      result = []
+      # returns first current file even when not yet open
+      result << @argf.file.path
+      result << @argf.file.path while @argf.gets
+      # returns last current file even when closed
+      result << @argf.file.path
+      result.should == [@file1, @file1, @file1, @file2, @file2, @file2]
+    end
+  end
+end

spec/ruby/core/argf/filename_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/filename', __FILE__)
+
+describe "ARGF.filename" do
+  it_behaves_like :argf_filename, :filename
+end

spec/ruby/core/argf/fileno_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/fileno', __FILE__)
+
+describe "ARGF.fileno" do
+  it_behaves_like :argf_fileno, :fileno
+end

spec/ruby/core/argf/fixtures/bin_file.txt

@@ -0,0 +1,2 @@
+test
+test

spec/ruby/core/argf/fixtures/file1.txt

@@ -0,0 +1,2 @@
+file1.1
+file1.2

spec/ruby/core/argf/fixtures/file2.txt

@@ -0,0 +1,2 @@
+line2.1
+line2.2

spec/ruby/core/argf/fixtures/filename.rb

@@ -0,0 +1,3 @@
+puts $FILENAME while ARGF.gets
+# returns last current file even when closed
+puts $FILENAME

spec/ruby/core/argf/fixtures/lineno.rb

@@ -0,0 +1,5 @@
+puts $.
+ARGF.gets
+puts $.
+ARGF.gets
+puts $.

spec/ruby/core/argf/fixtures/rewind.rb

@@ -0,0 +1,5 @@
+puts ARGF.lineno
+ARGF.gets
+puts ARGF.lineno
+ARGF.rewind
+puts ARGF.lineno

spec/ruby/core/argf/fixtures/stdin.txt

@@ -0,0 +1,2 @@
+stdin.1
+stdin.2

spec/ruby/core/argf/getc_spec.rb

@@ -0,0 +1,20 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/getc', __FILE__)
+
+describe "ARGF.getc" do
+  it_behaves_like :argf_getc, :getc
+end
+
+describe "ARGF.getc" do
+  before :each do
+    @file1 = fixture __FILE__, "file1.txt"
+    @file2 = fixture __FILE__, "file2.txt"
+  end
+
+  it "returns nil when end of stream reached" do
+    argf [@file1, @file2] do
+      @argf.read
+      @argf.getc.should == nil
+    end
+  end
+end

spec/ruby/core/argf/gets_spec.rb

@@ -0,0 +1,51 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/gets', __FILE__)
+
+describe "ARGF.gets" do
+  it_behaves_like :argf_gets, :gets
+end
+
+describe "ARGF.gets" do
+  it_behaves_like :argf_gets_inplace_edit, :gets
+end
+
+describe "ARGF.gets" do
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+    @file2_name = fixture __FILE__, "file2.txt"
+
+    @file1 = File.readlines @file1_name
+    @file2 = File.readlines @file2_name
+  end
+
+  it "returns nil when reaching end of files" do
+    argf [@file1_name, @file2_name] do
+      total = @file1.size + @file2.size
+      total.times { @argf.gets }
+      @argf.gets.should == nil
+    end
+  end
+
+  with_feature :encoding do
+    before :each do
+      @external = Encoding.default_external
+      @internal = Encoding.default_internal
+
+      Encoding.default_external = Encoding::UTF_8
+      Encoding.default_internal = nil
+    end
+
+    after :each do
+      Encoding.default_external = @external
+      Encoding.default_internal = @internal
+    end
+
+    it "reads the contents of the file with default encoding" do
+      Encoding.default_external = Encoding::US_ASCII
+      argf [@file1_name, @file2_name] do
+        @argf.gets.encoding.should == Encoding::US_ASCII
+      end
+    end
+  end
+
+end

spec/ruby/core/argf/lineno_spec.rb

@@ -0,0 +1,30 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "ARGF.lineno" do
+  before :each do
+    @file1 = fixture __FILE__, "file1.txt"
+    @file2 = fixture __FILE__, "file2.txt"
+  end
+
+  # NOTE: this test assumes that fixtures files have two lines each
+  # TODO: break this into four specs
+  it "returns the current line number on each file" do
+    argf [@file1, @file2] do
+      @argf.lineno = 0
+      @argf.gets
+      @argf.lineno.should == 1
+      @argf.gets
+      @argf.lineno.should == 2
+      @argf.gets
+      @argf.lineno.should == 3
+      @argf.gets
+      @argf.lineno.should == 4
+    end
+  end
+
+  it "aliases to $." do
+    script = fixture __FILE__, "lineno.rb"
+    out = ruby_exe(script, args: [@file1, @file2])
+    out.should == "0\n1\n2\n"
+  end
+end

spec/ruby/core/argf/lines_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/each_line', __FILE__)
+
+describe "ARGF.lines" do
+  it_behaves_like :argf_each_line, :lines
+end

spec/ruby/core/argf/path_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/filename', __FILE__)
+
+describe "ARGF.path" do
+  it_behaves_like :argf_filename, :path
+end

spec/ruby/core/argf/pos_spec.rb

@@ -0,0 +1,38 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/pos', __FILE__)
+
+describe "ARGF.pos" do
+  it_behaves_like :argf_pos, :pos
+end
+
+describe "ARGF.pos=" do
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+    @file2_name = fixture __FILE__, "file2.txt"
+
+    @file1 = File.readlines @file1_name
+    @file2 = File.readlines @file2_name
+  end
+
+  # NOTE: this test assumes that fixtures files have two lines each
+  it "sets the correct position in files" do
+    argf [@file1_name, @file2_name] do
+      @argf.pos = @file1.first.size
+      @argf.gets.should == @file1.last
+      @argf.pos = 0
+      @argf.gets.should == @file1.first
+
+      # finish reading file1
+      @argf.gets
+
+      @argf.gets
+      @argf.pos = 1
+      @argf.gets.should == @file2.first[1..-1]
+
+      @argf.pos = @file2.first.size + @file2.last.size - 1
+      @argf.gets.should == @file2.last[-1,1]
+      @argf.pos = 1000
+      @argf.read.should == ""
+    end
+  end
+end

spec/ruby/core/argf/read_nonblock_spec.rb

@@ -0,0 +1,82 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/read', __FILE__)
+
+platform_is_not :windows do
+  describe 'ARGF.read_nonblock' do
+    it_behaves_like :argf_read, :read_nonblock
+
+    before do
+      @file1_name = fixture(__FILE__, 'file1.txt')
+      @file2_name = fixture(__FILE__, 'file2.txt')
+
+      @file1 = File.read(@file1_name)
+      @file2 = File.read(@file2_name)
+
+      @chunk1 = File.read(@file1_name, 4)
+      @chunk2 = File.read(@file2_name, 4)
+    end
+
+    it 'reads up to the given amount of bytes' do
+      argf [@file1_name] do
+        @argf.read_nonblock(4).should == @chunk1
+      end
+    end
+
+    describe 'when using multiple files' do
+      it 'reads up to the given amount of bytes from the first file' do
+        argf [@file1_name, @file2_name] do
+          @argf.read_nonblock(4).should == @chunk1
+        end
+      end
+
+      it 'returns an empty String when reading after having read the first file in its entirety' do
+        argf [@file1_name, @file2_name] do
+          @argf.read_nonblock(File.size(@file1_name)).should == @file1
+          @argf.read_nonblock(4).should == ''
+        end
+      end
+    end
+
+    it 'reads up to the given bytes from STDIN' do
+      stdin = ruby_exe('print ARGF.read_nonblock(4)', :args => "< #{@file1_name}")
+
+      stdin.should == @chunk1
+    end
+
+    it 'reads up to the given bytes from a file when a file and STDIN are present' do
+      stdin = ruby_exe("print ARGF.read_nonblock(4)", :args => "#{@file1_name} - < #{@file2_name}")
+
+      stdin.should == @chunk1
+    end
+
+    context "with STDIN" do
+      before do
+        @r, @w = IO.pipe
+        @stdin = $stdin
+        $stdin = @r
+      end
+
+      after do
+        $stdin = @stdin
+        @w.close
+        @r.close unless @r.closed?
+      end
+
+      it 'raises IO::EAGAINWaitReadable when empty' do
+        argf ['-'] do
+          lambda {
+            @argf.read_nonblock(4)
+          }.should raise_error(IO::EAGAINWaitReadable)
+        end
+      end
+
+      ruby_version_is "2.3" do
+        it 'returns :wait_readable when the :exception is set to false' do
+          argf ['-'] do
+            @argf.read_nonblock(4, nil, exception: false).should == :wait_readable
+          end
+        end
+      end
+    end
+  end
+end

spec/ruby/core/argf/read_spec.rb

@@ -0,0 +1,87 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/read', __FILE__)
+
+describe "ARGF.read" do
+  it_behaves_like :argf_read, :read
+
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+    @file2_name = fixture __FILE__, "file2.txt"
+    @stdin_name = fixture __FILE__, "stdin.txt"
+
+    @file1 = File.read @file1_name
+    @file2 = File.read @file2_name
+    @stdin = File.read @stdin_name
+  end
+
+  it "reads the contents of a file" do
+    argf [@file1_name] do
+      @argf.read().should == @file1
+    end
+  end
+
+  it "treats first nil argument as no length limit" do
+    argf [@file1_name] do
+      @argf.read(nil).should == @file1
+    end
+  end
+
+  it "reads the contents of two files" do
+    argf [@file1_name, @file2_name] do
+      @argf.read.should ==  @file1 + @file2
+    end
+  end
+
+  it "reads the contents of one file and some characters from the second" do
+    argf [@file1_name, @file2_name] do
+      len = @file1.size + (@file2.size / 2)
+      @argf.read(len).should ==  (@file1 + @file2)[0,len]
+    end
+  end
+
+  it "reads across two files consecutively" do
+    argf [@file1_name, @file2_name] do
+      @argf.read(@file1.size - 2).should == @file1[0..-3]
+      @argf.read(2+5).should == @file1[-2..-1] + @file2[0,5]
+    end
+  end
+
+  it "reads the contents of stdin" do
+    stdin = ruby_exe("print ARGF.read", args: "< #{@stdin_name}")
+    stdin.should == @stdin
+  end
+
+  it "reads the contents of one file and stdin" do
+    stdin = ruby_exe("print ARGF.read", args: "#{@file1_name} - < #{@stdin_name}")
+    stdin.should == @file1 + @stdin
+  end
+
+  it "reads the contents of the same file twice" do
+    argf [@file1_name, @file1_name] do
+      @argf.read.should == @file1 + @file1
+    end
+  end
+
+  with_feature :encoding do
+
+    before :each do
+      @external = Encoding.default_external
+      @internal = Encoding.default_internal
+
+      Encoding.default_external = Encoding::UTF_8
+      Encoding.default_internal = nil
+    end
+
+    after :each do
+      Encoding.default_external = @external
+      Encoding.default_internal = @internal
+    end
+
+    it "reads the contents of the file with default encoding" do
+      Encoding.default_external = Encoding::US_ASCII
+      argf [@file1_name, @file2_name] do
+        @argf.read.encoding.should == Encoding::US_ASCII
+      end
+    end
+  end
+end

spec/ruby/core/argf/readchar_spec.rb

@@ -0,0 +1,19 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/getc', __FILE__)
+
+describe "ARGF.getc" do
+  it_behaves_like :argf_getc, :readchar
+end
+
+describe "ARGF.readchar" do
+  before :each do
+    @file1 = fixture __FILE__, "file1.txt"
+    @file2 = fixture __FILE__, "file2.txt"
+  end
+
+  it "raises EOFError when end of stream reached" do
+    argf [@file1, @file2] do
+      lambda { while @argf.readchar; end }.should raise_error(EOFError)
+    end
+  end
+end

spec/ruby/core/argf/readline_spec.rb

@@ -0,0 +1,23 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/gets', __FILE__)
+
+describe "ARGF.readline" do
+  it_behaves_like :argf_gets, :readline
+end
+
+describe "ARGF.readline" do
+  it_behaves_like :argf_gets_inplace_edit, :readline
+end
+
+describe "ARGF.readline" do
+  before :each do
+    @file1 = fixture __FILE__, "file1.txt"
+    @file2 = fixture __FILE__, "file2.txt"
+  end
+
+  it "raises an EOFError when reaching end of files" do
+    argf [@file1, @file2] do
+      lambda { while @argf.readline; end }.should raise_error(EOFError)
+    end
+  end
+end

spec/ruby/core/argf/readlines_spec.rb

@@ -0,0 +1,6 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/readlines', __FILE__)
+
+describe "ARGF.readlines" do
+  it_behaves_like :argf_readlines, :readlines
+end

spec/ruby/core/argf/readpartial_spec.rb

@@ -0,0 +1,77 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/read', __FILE__)
+
+describe "ARGF.readpartial" do
+  it_behaves_like :argf_read, :readpartial
+
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+    @file2_name = fixture __FILE__, "file2.txt"
+    @stdin_name = fixture __FILE__, "stdin.txt"
+
+    @file1 = File.read @file1_name
+    @file2 = File.read @file2_name
+    @stdin = File.read @stdin_name
+  end
+
+  it "raises an ArgumentError if called without a maximum read length" do
+    argf [@file1_name] do
+      lambda { @argf.readpartial }.should raise_error(ArgumentError)
+    end
+  end
+
+  it "reads maximum number of bytes from one file at a time" do
+    argf [@file1_name, @file2_name] do
+      len = @file1.size + @file2.size
+      @argf.readpartial(len).should == @file1
+    end
+  end
+
+  it "clears output buffer even if EOFError is raised because @argf is at end" do
+    begin
+      output = "to be cleared"
+
+      argf [@file1_name] do
+        @argf.read
+        @argf.readpartial(1, output)
+      end
+    rescue EOFError
+      output.should == ""
+    end
+  end
+
+  it "reads maximum number of bytes from one file at a time" do
+    argf [@file1_name, @file2_name] do
+      len = @file1.size + @file2.size
+      @argf.readpartial(len).should == @file1
+    end
+  end
+
+  it "returns an empty string if EOFError is raised while reading any but the last file" do
+    argf [@file1_name, @file2_name] do
+      @argf.readpartial(@file1.size)
+      @argf.readpartial(1).should == ""
+    end
+  end
+
+  ruby_version_is "2.3" do
+    it "raises an EOFError if the exception was raised while reading the last file" do
+      argf [@file1_name, @file2_name] do
+        @argf.readpartial(@file1.size)
+        @argf.readpartial(1)
+        @argf.readpartial(@file2.size)
+        lambda { @argf.readpartial(1) }.should raise_error(EOFError)
+        lambda { @argf.readpartial(1) }.should raise_error(EOFError)
+      end
+    end
+  end
+
+  it "raises an EOFError if the exception was raised while reading STDIN" do
+    ruby_str = <<-STR
+      print ARGF.readpartial(#{@stdin.size})
+      ARGF.readpartial(1) rescue print $!.class
+    STR
+    stdin = ruby_exe(ruby_str, args: "< #{@stdin_name}", escape: true)
+    stdin.should == @stdin + "EOFError"
+  end
+end

spec/ruby/core/argf/rewind_spec.rb

@@ -0,0 +1,39 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "ARGF.rewind" do
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+    @file2_name = fixture __FILE__, "file2.txt"
+
+    @file1 = File.readlines @file1_name
+    @file2 = File.readlines @file2_name
+  end
+
+  # NOTE: this test assumes that fixtures files have two lines each
+  it "goes back to beginning of current file" do
+    argf [@file1_name, @file2_name] do
+      @argf.gets
+      @argf.rewind
+      @argf.gets.should == @file1.first
+
+      @argf.gets # finish reading file1
+
+      @argf.gets
+      @argf.rewind
+      @argf.gets.should == @file2.first
+    end
+  end
+
+  it "resets ARGF.lineno to 0" do
+    script = fixture __FILE__, "rewind.rb"
+    out = ruby_exe(script, args: [@file1_name, @file2_name])
+    out.should == "0\n1\n0\n"
+  end
+
+  it "raises an ArgumentError when end of stream reached" do
+    argf [@file1_name, @file2_name] do
+      @argf.read
+      lambda { @argf.rewind }.should raise_error(ArgumentError)
+    end
+  end
+end

spec/ruby/core/argf/seek_spec.rb

@@ -0,0 +1,63 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "ARGF.seek" do
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+    @file2_name = fixture __FILE__, "file2.txt"
+
+    @file1 = File.readlines @file1_name
+    @file2 = File.readlines @file2_name
+  end
+
+  it "sets the absolute position relative to beginning of file" do
+    argf [@file1_name, @file2_name] do
+      @argf.seek 2
+      @argf.gets.should == @file1.first[2..-1]
+      @argf.seek @file1.first.size
+      @argf.gets.should == @file1.last
+      @argf.seek 0, IO::SEEK_END
+      @argf.gets.should == @file2.first
+    end
+  end
+
+  it "sets the position relative to current position in file" do
+    argf [@file1_name, @file2_name] do
+      @argf.seek(0, IO::SEEK_CUR)
+      @argf.gets.should == @file1.first
+      @argf.seek(-@file1.first.size+2, IO::SEEK_CUR)
+      @argf.gets.should == @file1.first[2..-1]
+      @argf.seek(1, IO::SEEK_CUR)
+      @argf.gets.should == @file1.last[1..-1]
+      @argf.seek(3, IO::SEEK_CUR)
+      @argf.gets.should == @file2.first
+      @argf.seek(@file1.last.size, IO::SEEK_CUR)
+      @argf.gets.should == nil
+    end
+  end
+
+  it "sets the absolute position relative to end of file" do
+    argf [@file1_name, @file2_name] do
+      @argf.seek(-@file1.first.size-@file1.last.size, IO::SEEK_END)
+      @argf.gets.should == @file1.first
+      @argf.seek(-6, IO::SEEK_END)
+      @argf.gets.should == @file1.last[-6..-1]
+      @argf.seek(-4, IO::SEEK_END)
+      @argf.gets.should == @file1.last[4..-1]
+      @argf.gets.should == @file2.first
+      @argf.seek(-6, IO::SEEK_END)
+      @argf.gets.should == @file2.last[-6..-1]
+    end
+  end
+end
+
+describe "ARGF.seek" do
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+  end
+
+  it "takes at least one argument (offset)" do
+    argf [@file1_name] do
+      lambda { @argf.seek }.should raise_error(ArgumentError)
+    end
+  end
+end

spec/ruby/core/argf/set_encoding_spec.rb

@@ -0,0 +1,41 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "ARGF.set_encoding" do
+  before :each do
+    @file = fixture __FILE__, "file1.txt"
+  end
+
+  it "sets the external encoding when passed an encoding instance" do
+    argf [@file] do
+      @argf.set_encoding(Encoding::US_ASCII)
+      @argf.external_encoding.should == Encoding::US_ASCII
+      @argf.gets.encoding.should == Encoding::US_ASCII
+    end
+  end
+
+  it "sets the external encoding when passed an encoding name" do
+    argf [@file] do
+      @argf.set_encoding("us-ascii")
+      @argf.external_encoding.should == Encoding::US_ASCII
+      @argf.gets.encoding.should == Encoding::US_ASCII
+    end
+  end
+
+  it "sets the external, internal encoding when passed two encoding instances" do
+    argf [@file] do
+      @argf.set_encoding(Encoding::US_ASCII, Encoding::EUC_JP)
+      @argf.external_encoding.should == Encoding::US_ASCII
+      @argf.internal_encoding.should == Encoding::EUC_JP
+      @argf.gets.encoding.should == Encoding::EUC_JP
+    end
+  end
+
+  it "sets the external, internal encoding when passed 'ext:int' String" do
+    argf [@file] do
+      @argf.set_encoding("us-ascii:euc-jp")
+      @argf.external_encoding.should == Encoding::US_ASCII
+      @argf.internal_encoding.should == Encoding::EUC_JP
+      @argf.gets.encoding.should == Encoding::EUC_JP
+    end
+  end
+end

spec/ruby/core/argf/shared/each_byte.rb

@@ -0,0 +1,58 @@
+describe :argf_each_byte, shared: true do
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+    @file2_name = fixture __FILE__, "file2.txt"
+
+    @bytes = []
+    File.read(@file1_name).each_byte { |b| @bytes << b }
+    File.read(@file2_name).each_byte { |b| @bytes << b }
+  end
+
+  it "yields each byte of all streams to the passed block" do
+    argf [@file1_name, @file2_name] do
+      bytes = []
+      @argf.send(@method) { |b| bytes << b }
+      bytes.should == @bytes
+    end
+  end
+
+  it "returns self when passed a block" do
+    argf [@file1_name, @file2_name] do
+      @argf.send(@method) {}.should equal(@argf)
+    end
+  end
+
+  it "returns an Enumerator when passed no block" do
+    argf [@file1_name, @file2_name] do
+      enum = @argf.send(@method)
+      enum.should be_an_instance_of(Enumerator)
+
+      bytes = []
+      enum.each { |b| bytes << b }
+      bytes.should == @bytes
+    end
+  end
+
+  describe "when no block is given" do
+    it "returns an Enumerator" do
+      argf [@file1_name, @file2_name] do
+        enum = @argf.send(@method)
+        enum.should be_an_instance_of(Enumerator)
+
+        bytes = []
+        enum.each { |b| bytes << b }
+        bytes.should == @bytes
+      end
+    end
+
+    describe "returned Enumerator" do
+      describe "size" do
+        it "should return nil" do
+          argf [@file1_name, @file2_name] do
+            @argf.send(@method).size.should == nil
+          end
+        end
+      end
+    end
+  end
+end

spec/ruby/core/argf/shared/each_char.rb

@@ -0,0 +1,58 @@
+describe :argf_each_char, shared: true do
+  before :each do
+    @file1_name = fixture __FILE__, "file1.txt"
+    @file2_name = fixture __FILE__, "file2.txt"
+
+    @chars = []
+    File.read(@file1_name).each_char { |c| @chars << c }
+    File.read(@file2_name).each_char { |c| @chars << c }
+  end
+
+  it "yields each char of all streams to the passed block" do
+    argf [@file1_name, @file2_name] do
+      chars = []
+      @argf.send(@method) { |c| chars << c }
+      chars.should == @chars
+    end
+  end
+
+  it "returns self when passed a block" do
+    argf [@file1_name, @file2_name] do
+      @argf.send(@method) {}.should equal(@argf)
+    end
+  end
+
+  it "returns an Enumerator when passed no block" do
+    argf [@file1_name, @file2_name] do
+      enum = @argf.send(@method)
+      enum.should be_an_instance_of(Enumerator)
+
+      chars = []
+      enum.each { |c| chars << c }
+      chars.should == @chars
+    end
+  end
+
+  describe "when no block is given" do
+    it "returns an Enumerator" do
+      argf [@file1_name, @file2_name] do
+        enum = @argf.send(@method)
+        enum.should be_an_instance_of(Enumerator)
+
+        chars = []
+        enum.each { |c| chars << c }
+        chars.should == @chars
+      end
+    end
+
+    describe "returned Enumerator" do
+      describe "size" do
+        it "should return nil" do
+          argf [@file1_name, @file2_name] do
+            @argf.send(@method).size.should == nil
+          end
+        end
+      end
+    end
+  end
+end