1 files changed, 37 insertions, 0 deletions
diff --git a/spec/mspec/lib/mspec/helpers/argf.rb b/spec/mspec/lib/mspec/helpers/argf.rb
new file mode 100644
index 0000000000..1ba48b9378
--- /dev/null
+++ b/spec/mspec/lib/mspec/helpers/argf.rb
@@ -0,0 +1,37 @@
+class Object
+  # Convenience helper for specs using ARGF.
+  # Set @argf to an instance of ARGF.class with the given +argv+.
+  # That instance must be used instead of ARGF as ARGF is global
+  # and it is not always possible to reset its state correctly.
+  #
+  # The helper yields to the block and then close
+  # the files open by the instance. Example:
+  #
+  #   describe "That" do
+  #     it "does something" do
+  #       argf ['a', 'b'] do
+  #         # do something
+  #       end
+  #     end
+  #   end
+  def argf(argv)
+    if argv.empty? or argv.length > 2
+      raise "Only 1 or 2 filenames are allowed for the argf helper so files can be properly closed: #{argv.inspect}"
+    end
+    @argf ||= nil
+    raise "Cannot nest calls to the argf helper" if @argf
+
+    @argf = ARGF.class.new(*argv)
+    @__mspec_saved_argf_file__ = @argf.file
+    begin
+      yield
+    ensure
+      file1 = @__mspec_saved_argf_file__
+      file2 = @argf.file # Either the first file or the second
+      file1.close if !file1.closed? and file1 != STDIN
+      file2.close if !file2.closed? and file2 != STDIN
+      @argf = nil
+      @__mspec_saved_argf_file__ = nil
+    end
+  end
+end