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diff --git a/spec/ruby/core/array/sample_spec.rb b/spec/ruby/core/array/sample_spec.rb
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+++ b/spec/ruby/core/array/sample_spec.rb
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+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "Array#sample" do
+  it "samples evenly" do
+    ary = [0, 1, 2, 3]
+    3.times do |i|
+      counts = [0, 0, 0, 0]
+      4000.times do
+        counts[ary.sample(3)[i]] += 1
+      end
+      counts.each do |count|
+        (800..1200).should include(count)
+      end
+    end
+  end
+
+  it "returns nil for an empty Array" do
+    [].sample.should be_nil
+  end
+
+  it "returns a single value when not passed a count" do
+    [4].sample.should equal(4)
+  end
+
+  it "returns an empty Array when passed zero" do
+    [4].sample(0).should == []
+  end
+
+  it "returns an Array of elements when passed a count" do
+    [1, 2, 3, 4].sample(3).should be_an_instance_of(Array)
+  end
+
+  it "returns elements from the Array" do
+    array = [1, 2, 3, 4]
+    array.sample(3).all? { |x| array.should include(x) }
+  end
+
+  it "returns at most the number of elements in the Array" do
+    array = [1, 2, 3, 4]
+    result = array.sample(20)
+    result.size.should == 4
+  end
+
+  it "does not return the same value if the Array has unique values" do
+    array = [1, 2, 3, 4]
+    result = array.sample(20)
+    result.sort.should == array
+  end
+
+  it "may return the same value if the array is not unique" do
+    [4, 4].sample(2).should == [4,4]
+  end
+
+  it "calls #to_int to convert the count when passed an Object" do
+    [1, 2, 3, 4].sample(mock_int(2)).size.should == 2
+  end
+
+  it "raises ArgumentError when passed a negative count" do
+    lambda { [1, 2].sample(-1) }.should raise_error(ArgumentError)
+  end
+
+  it "does not return subclass instances with Array subclass" do
+    ArraySpecs::MyArray[1, 2, 3].sample(2).should be_an_instance_of(Array)
+  end
+
+  describe "with options" do
+    it "calls #to_hash to convert the passed Object" do
+      obj = mock("array_sample")
+      obj.should_receive(:to_hash).and_return({})
+      obj.should_not_receive(:to_int)
+
+      [1, 2].sample(obj).should be_an_instance_of(Fixnum)
+    end
+
+    it "calls #to_int on the first argument and #to_hash on the second when passed Objects" do
+      count = mock("array_sample_count")
+      count.should_receive(:to_int).and_return(2)
+      options = mock("array_sample_options")
+      options.should_receive(:to_hash).and_return({})
+
+      [1, 2].sample(count, options).size.should == 2
+    end
+
+    it "calls #rand on the Object passed by the :random key in the arguments Hash" do
+      obj = mock("array_sample_random")
+      obj.should_receive(:rand).and_return(0.5)
+
+      [1, 2].sample(random: obj).should be_an_instance_of(Fixnum)
+    end
+
+    it "raises a NoMethodError if an object passed for the RNG does not define #rand" do
+      obj = BasicObject.new
+
+      lambda { [1, 2].sample(random: obj) }.should raise_error(NoMethodError)
+    end
+
+    describe "when the object returned by #rand is a Fixnum" do
+      it "uses the fixnum as index" do
+        random = mock("array_sample_random_ret")
+        random.should_receive(:rand).and_return(0)
+
+        [1, 2].sample(random: random).should == 1
+
+        random = mock("array_sample_random_ret")
+        random.should_receive(:rand).and_return(1)
+
+        [1, 2].sample(random: random).should == 2
+      end
+
+      it "raises a RangeError if the value is less than zero" do
+        random = mock("array_sample_random")
+        random.should_receive(:rand).and_return(-1)
+
+        lambda { [1, 2].sample(random: random) }.should raise_error(RangeError)
+      end
+
+      it "raises a RangeError if the value is equal to the Array size" do
+        random = mock("array_sample_random")
+        random.should_receive(:rand).and_return(2)
+
+        lambda { [1, 2].sample(random: random) }.should raise_error(RangeError)
+      end
+    end
+  end
+
+  describe "when the object returned by #rand is not a Fixnum but responds to #to_int" do
+    it "calls #to_int on the Object" do
+      value = mock("array_sample_random_value")
+      value.should_receive(:to_int).and_return(1)
+      random = mock("array_sample_random")
+      random.should_receive(:rand).and_return(value)
+
+      [1, 2].sample(random: random).should == 2
+    end
+
+    it "raises a RangeError if the value is less than zero" do
+      value = mock("array_sample_random_value")
+      value.should_receive(:to_int).and_return(-1)
+      random = mock("array_sample_random")
+      random.should_receive(:rand).and_return(value)
+
+      lambda { [1, 2].sample(random: random) }.should raise_error(RangeError)
+    end
+
+    it "raises a RangeError if the value is equal to the Array size" do
+      value = mock("array_sample_random_value")
+      value.should_receive(:to_int).and_return(2)
+      random = mock("array_sample_random")
+      random.should_receive(:rand).and_return(value)
+
+      lambda { [1, 2].sample(random: random) }.should raise_error(RangeError)
+    end
+  end
+end