1 files changed, 107 insertions, 0 deletions
diff --git a/spec/ruby/core/kernel/system_spec.rb b/spec/ruby/core/kernel/system_spec.rb
new file mode 100644
index 0000000000..aee75441a2
--- /dev/null
+++ b/spec/ruby/core/kernel/system_spec.rb
@@ -0,0 +1,107 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe :kernel_system, shared: true do
+  it "executes the specified command in a subprocess" do
+    lambda { @object.system("echo a") }.should output_to_fd("a\n")
+
+    $?.should be_an_instance_of Process::Status
+    $?.success?.should == true
+  end
+
+  it "returns true when the command exits with a zero exit status" do
+    @object.system(ruby_cmd('exit 0')).should == true
+
+    $?.should be_an_instance_of Process::Status
+    $?.success?.should == true
+    $?.exitstatus.should == 0
+  end
+
+  it "returns false when the command exits with a non-zero exit status" do
+    @object.system(ruby_cmd('exit 1')).should == false
+
+    $?.should be_an_instance_of Process::Status
+    $?.success?.should == false
+    $?.exitstatus.should == 1
+  end
+
+  it "returns nil when command execution fails" do
+    @object.system("sad").should be_nil
+
+    $?.should be_an_instance_of Process::Status
+    $?.pid.should be_kind_of(Integer)
+    $?.exitstatus.should == 127
+  end
+
+  it "does not write to stderr when command execution fails" do
+    lambda { @object.system("sad") }.should output_to_fd("", STDERR)
+  end
+
+  platform_is_not :windows do
+    before :each do
+      @shell = ENV['SHELL']
+    end
+
+    after :each do
+      ENV['SHELL'] = @shell
+    end
+
+    it "executes with `sh` if the command contains shell characters" do
+      lambda { @object.system("echo $0") }.should output_to_fd("sh\n")
+    end
+
+    it "ignores SHELL env var and always uses `sh`" do
+      ENV['SHELL'] = "/bin/fakeshell"
+      lambda { @object.system("echo $0") }.should output_to_fd("sh\n")
+    end
+  end
+
+  before :each do
+    ENV['TEST_SH_EXPANSION'] = 'foo'
+    @shell_var = '$TEST_SH_EXPANSION'
+    platform_is :windows do
+      @shell_var = '%TEST_SH_EXPANSION%'
+    end
+  end
+
+  after :each do
+    ENV.delete('TEST_SH_EXPANSION')
+  end
+
+  it "expands shell variables when given a single string argument" do
+    lambda { @object.system("echo #{@shell_var}") }.should output_to_fd("foo\n")
+  end
+
+  platform_is_not :windows do
+    it "does not expand shell variables when given multiples arguments" do
+      lambda { @object.system("echo", @shell_var) }.should output_to_fd("#{@shell_var}\n")
+    end
+  end
+
+  platform_is :windows do
+    it "does expand shell variables when given multiples arguments" do
+      # See https://bugs.ruby-lang.org/issues/12231
+      lambda { @object.system("echo", @shell_var) }.should output_to_fd("foo\n")
+    end
+  end
+
+  platform_is :windows do
+    it "runs commands starting with any number of @ using shell" do
+      `#{ruby_cmd("p system 'does_not_exist'")} 2>NUL`.chomp.should == "nil"
+      @object.system('@does_not_exist 2>NUL').should == false
+      @object.system("@@@#{ruby_cmd('exit 0')}").should == true
+    end
+  end
+end
+
+describe "Kernel#system" do
+  it "is a private method" do
+    Kernel.should have_private_instance_method(:system)
+  end
+
+  it_behaves_like :kernel_system, :system, KernelSpecs::Method.new
+end
+
+describe "Kernel.system" do
+  it_behaves_like :kernel_system, :system, Kernel
+end