1 files changed, 68 insertions, 0 deletions
diff --git a/spec/rubyspec/core/array/product_spec.rb b/spec/rubyspec/core/array/product_spec.rb
new file mode 100644
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+++ b/spec/rubyspec/core/array/product_spec.rb
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+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "Array#product" do
+  it "returns converted arguments using :to_ary" do
+    lambda{ [1].product(2..3) }.should raise_error(TypeError)
+    ar = ArraySpecs::ArrayConvertable.new(2,3)
+    [1].product(ar).should == [[1,2],[1,3]]
+    ar.called.should == :to_ary
+  end
+
+  it "returns the expected result" do
+    [1,2].product([3,4,5],[6,8]).should == [[1, 3, 6], [1, 3, 8], [1, 4, 6], [1, 4, 8], [1, 5, 6], [1, 5, 8],
+                                            [2, 3, 6], [2, 3, 8], [2, 4, 6], [2, 4, 8], [2, 5, 6], [2, 5, 8]]
+  end
+
+  it "has no required argument" do
+    [1,2].product.should == [[1],[2]]
+  end
+
+  it "returns an empty array when the argument is an empty array" do
+    [1, 2].product([]).should == []
+  end
+
+  it "does not attempt to produce an unreasonable number of products" do
+    a = (0..100).to_a
+    lambda do
+      a.product(a, a, a, a, a, a, a, a, a, a)
+    end.should raise_error(RangeError)
+  end
+
+  describe "when given a block" do
+    it "yields all combinations in turn" do
+      acc = []
+      [1,2].product([3,4,5],[6,8]){|array| acc << array}
+      acc.should == [[1, 3, 6], [1, 3, 8], [1, 4, 6], [1, 4, 8], [1, 5, 6], [1, 5, 8],
+                     [2, 3, 6], [2, 3, 8], [2, 4, 6], [2, 4, 8], [2, 5, 6], [2, 5, 8]]
+
+      acc = []
+      [1,2].product([3,4,5],[],[6,8]){|array| acc << array}
+      acc.should be_empty
+    end
+
+    it "returns self" do
+      a = [1, 2, 3].freeze
+
+      a.product([1, 2]) { |p| p.first }.should == a
+    end
+
+    it "will ignore unreasonable numbers of products and yield anyway" do
+      a = (0..100).to_a
+      lambda do
+        a.product(a, a, a, a, a, a, a, a, a, a)
+      end.should raise_error(RangeError)
+    end
+  end
+
+  describe "when given an empty block" do
+    it "returns self" do
+      arr = [1,2]
+      arr.product([3,4,5],[6,8]){}.should equal(arr)
+      arr = []
+      arr.product([3,4,5],[6,8]){}.should equal(arr)
+      arr = [1,2]
+      arr.product([]){}.should equal(arr)
+    end
+  end
+end