6 files changed, 96 insertions, 20 deletions
diff --git a/spec/ruby/command_line/dash_upper_c_spec.rb b/spec/ruby/command_line/dash_upper_c_spec.rb
index 761beaadab..ece1b32105 100644
--- a/spec/ruby/command_line/dash_upper_c_spec.rb
+++ b/spec/ruby/command_line/dash_upper_c_spec.rb
@@ -1,23 +1,6 @@
 require_relative '../spec_helper'
+require_relative 'shared/change_directory'
 
-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 'does not need a space after -C for the argument' 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
+describe "The -C command line option" do
+  it_behaves_like :command_line_change_directory, "-C"
 end
diff --git a/spec/ruby/command_line/dash_upper_x_spec.rb b/spec/ruby/command_line/dash_upper_x_spec.rb
new file mode 100644
index 0000000000..8ef9aae4b1
--- /dev/null
+++ b/spec/ruby/command_line/dash_upper_x_spec.rb
@@ -0,0 +1,6 @@
+require_relative '../spec_helper'
+require_relative 'shared/change_directory'
+
+describe "The -X command line option" do
+  it_behaves_like :command_line_change_directory, "-X"
+end
diff --git a/spec/ruby/command_line/feature_spec.rb b/spec/ruby/command_line/feature_spec.rb
new file mode 100644
index 0000000000..fa2a82cb4b
--- /dev/null
+++ b/spec/ruby/command_line/feature_spec.rb
@@ -0,0 +1,65 @@
+require_relative '../spec_helper'
+
+describe "The --enable and --disable flags" do
+
+  it "can be used with gems" do
+    ruby_exe("p defined?(Gem)", options: "--enable=gems").chomp.should == "\"constant\""
+    ruby_exe("p defined?(Gem)", options: "--disable=gems").chomp.should == "nil"
+    ruby_exe("p defined?(Gem)", options: "--enable-gems").chomp.should == "\"constant\""
+    ruby_exe("p defined?(Gem)", options: "--disable-gems").chomp.should == "nil"
+  end
+
+  it "can be used with gem" do
+    ruby_exe("p defined?(Gem)", options: "--enable=gem").chomp.should == "\"constant\""
+    ruby_exe("p defined?(Gem)", options: "--disable=gem").chomp.should == "nil"
+    ruby_exe("p defined?(Gem)", options: "--enable-gem").chomp.should == "\"constant\""
+    ruby_exe("p defined?(Gem)", options: "--disable-gem").chomp.should == "nil"
+  end
+
+  it "can be used with did_you_mean" do
+    ruby_exe("p defined?(DidYouMean)", options: "--enable=did_you_mean").chomp.should == "\"constant\""
+    ruby_exe("p defined?(DidYouMean)", options: "--disable=did_you_mean").chomp.should == "nil"
+    ruby_exe("p defined?(DidYouMean)", options: "--enable-did_you_mean").chomp.should == "\"constant\""
+    ruby_exe("p defined?(DidYouMean)", options: "--disable-did_you_mean").chomp.should == "nil"
+  end
+
+  it "can be used with rubyopt" do
+    ruby_exe("p $VERBOSE", options: "--enable=rubyopt", env: {'RUBYOPT' => '-w'}).chomp.should == "true"
+    ruby_exe("p $VERBOSE", options: "--disable=rubyopt", env: {'RUBYOPT' => '-w'}).chomp.should == "false"
+    ruby_exe("p $VERBOSE", options: "--enable-rubyopt", env: {'RUBYOPT' => '-w'}).chomp.should == "true"
+    ruby_exe("p $VERBOSE", options: "--disable-rubyopt", env: {'RUBYOPT' => '-w'}).chomp.should == "false"
+  end
+
+  it "can be used with frozen-string-literal" do
+    ruby_exe("p 'foo'.frozen?", options: "--enable=frozen-string-literal").chomp.should == "true"
+    ruby_exe("p 'foo'.frozen?", options: "--disable=frozen-string-literal").chomp.should == "false"
+    ruby_exe("p 'foo'.frozen?", options: "--enable-frozen-string-literal").chomp.should == "true"
+    ruby_exe("p 'foo'.frozen?", options: "--disable-frozen-string-literal").chomp.should == "false"
+  end
+
+  ruby_version_is "2.6" do
+    it "can be used with jit" do
+      ruby_exe("p RubyVM::MJIT.enabled?", options: "--enable=jit").chomp.should == "true"
+      ruby_exe("p RubyVM::MJIT.enabled?", options: "--disable=jit").chomp.should == "false"
+      ruby_exe("p RubyVM::MJIT.enabled?", options: "--enable-jit").chomp.should == "true"
+      ruby_exe("p RubyVM::MJIT.enabled?", options: "--disable-jit").chomp.should == "false"
+    end
+  end
+
+  it "can be used with all" do
+    e = "p [defined?(Gem), defined?(DidYouMean), $VERBOSE, 'foo'.frozen?]"
+    env = {'RUBYOPT' => '-w'}
+    ruby_exe(e, options: "--enable=all", env: env).chomp.should == "[\"constant\", \"constant\", true, true]"
+    ruby_exe(e, options: "--enable-all", env: env).chomp.should == "[\"constant\", \"constant\", true, true]"
+    ruby_exe(e, options: "--disable=all", env: env).chomp.should == "[nil, nil, false, false]"
+    ruby_exe(e, options: "--disable-all", env: env).chomp.should == "[nil, nil, false, false]"
+  end
+
+  it "prints a warning for unknown features" do
+    ruby_exe("p 14", options: "--enable=ruby-spec-feature-does-not-exist 2>&1").chomp.should include('warning: unknown argument for --enable')
+    ruby_exe("p 14", options: "--disable=ruby-spec-feature-does-not-exist 2>&1").chomp.should include('warning: unknown argument for --disable')
+    ruby_exe("p 14", options: "--enable-ruby-spec-feature-does-not-exist 2>&1").chomp.should include('warning: unknown argument for --enable')
+    ruby_exe("p 14", options: "--disable-ruby-spec-feature-does-not-exist 2>&1").chomp.should include('warning: unknown argument for --disable')
+  end
+
+end
diff --git a/spec/ruby/command_line/fixtures/dash_upper_c_script.rb b/spec/ruby/command_line/fixtures/change_directory_script.rb
index abe244705f..abe244705f 100644
--- a/spec/ruby/command_line/fixtures/dash_upper_c_script.rb
+++ b/spec/ruby/command_line/fixtures/change_directory_script.rb
diff --git a/spec/ruby/command_line/rubylib_spec.rb b/spec/ruby/command_line/rubylib_spec.rb
index 20e9c2cf95..b45919b997 100644
--- a/spec/ruby/command_line/rubylib_spec.rb
+++ b/spec/ruby/command_line/rubylib_spec.rb
@@ -30,6 +30,7 @@ describe "The RUBYLIB environment variable" do
     dir = tmp("rubylib/incl_front")
     ENV["RUBYLIB"] = @pre + dir
     paths = ruby_exe("puts $LOAD_PATH").lines.map(&:chomp)
+    paths.shift if paths.first.end_with?('/gem-rehash')
     if PlatformGuard.implementation? :ruby
       # In a MRI checkout, $PWD and some extra -I entries end up as
       # the first entries in $LOAD_PATH. So just assert that it's not last.
diff --git a/spec/ruby/command_line/shared/change_directory.rb b/spec/ruby/command_line/shared/change_directory.rb
new file mode 100644
index 0000000000..9cb6e90ac6
--- /dev/null
+++ b/spec/ruby/command_line/shared/change_directory.rb
@@ -0,0 +1,21 @@
+describe :command_line_change_directory, shared: true do
+  before :all do
+    @script  = fixture(__FILE__, 'change_directory_script.rb')
+    @tempdir = File.dirname(@script)
+  end
+
+  it 'changes the PWD when using a file' do
+    output = ruby_exe(@script, options: "#{@method} #{@tempdir}")
+    output.should == @tempdir
+  end
+
+  it 'does not need a space after -C for the argument' do
+    output = ruby_exe(@script, options: "#{@method}#{@tempdir}")
+    output.should == @tempdir
+  end
+
+  it 'changes the PWD when using -e' do
+    output = ruby_exe(nil, options: "#{@method} #{@tempdir} -e 'print Dir.pwd'")
+    output.should == @tempdir
+  end
+end