1 files changed, 24 insertions, 0 deletions
diff --git a/spec/ruby/core/argf/shared/fileno.rb b/spec/ruby/core/argf/shared/fileno.rb
new file mode 100644
index 0000000000..891e250ad9
--- /dev/null
+++ b/spec/ruby/core/argf/shared/fileno.rb
@@ -0,0 +1,24 @@
+describe :argf_fileno, shared: true 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 number on each file" do
+    argf [@file1, @file2] do
+      result = []
+      # returns first current file even when not yet open
+      result << @argf.send(@method) while @argf.gets
+      # returns last current file even when closed
+      result.map { |d| d.class }.should == [Fixnum, Fixnum, Fixnum, Fixnum]
+    end
+  end
+
+  it "raises an ArgumentError when called on a closed stream" do
+    argf [@file1] do
+      @argf.read
+      lambda { @argf.send(@method) }.should raise_error(ArgumentError)
+    end
+  end
+end