1 files changed, 87 insertions, 0 deletions
diff --git a/spec/ruby/core/array/last_spec.rb b/spec/ruby/core/array/last_spec.rb
new file mode 100644
index 0000000000..c707e3ff7e
--- /dev/null
+++ b/spec/ruby/core/array/last_spec.rb
@@ -0,0 +1,87 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "Array#last" do
+  it "returns the last element" do
+    [1, 1, 1, 1, 2].last.should == 2
+  end
+
+  it "returns nil if self is empty" do
+    [].last.should == nil
+  end
+
+  it "returns the last count elements if given a count" do
+    [1, 2, 3, 4, 5, 9].last(3).should == [4, 5, 9]
+  end
+
+  it "returns an empty array when passed a count on an empty array" do
+    [].last(0).should == []
+    [].last(1).should == []
+  end
+
+  it "returns an empty array when count == 0" do
+    [1, 2, 3, 4, 5].last(0).should == []
+  end
+
+  it "returns an array containing the last element when passed count == 1" do
+    [1, 2, 3, 4, 5].last(1).should == [5]
+  end
+
+  it "raises an ArgumentError when count is negative" do
+    lambda { [1, 2].last(-1) }.should raise_error(ArgumentError)
+  end
+
+  it "returns the entire array when count > length" do
+    [1, 2, 3, 4, 5, 9].last(10).should == [1, 2, 3, 4, 5, 9]
+  end
+
+  it "returns an array which is independent to the original when passed count" do
+    ary = [1, 2, 3, 4, 5]
+    ary.last(0).replace([1,2])
+    ary.should == [1, 2, 3, 4, 5]
+    ary.last(1).replace([1,2])
+    ary.should == [1, 2, 3, 4, 5]
+    ary.last(6).replace([1,2])
+    ary.should == [1, 2, 3, 4, 5]
+  end
+
+  it "properly handles recursive arrays" do
+    empty = ArraySpecs.empty_recursive_array
+    empty.last.should equal(empty)
+
+    array = ArraySpecs.recursive_array
+    array.last.should equal(array)
+  end
+
+  it "tries to convert the passed argument to an Integer usinig #to_int" do
+    obj = mock('to_int')
+    obj.should_receive(:to_int).and_return(2)
+    [1, 2, 3, 4, 5].last(obj).should == [4, 5]
+  end
+
+  it "raises a TypeError if the passed argument is not numeric" do
+    lambda { [1,2].last(nil) }.should raise_error(TypeError)
+    lambda { [1,2].last("a") }.should raise_error(TypeError)
+
+    obj = mock("nonnumeric")
+    lambda { [1,2].last(obj) }.should raise_error(TypeError)
+  end
+
+  it "does not return subclass instance on Array subclasses" do
+    ArraySpecs::MyArray[].last(0).should be_an_instance_of(Array)
+    ArraySpecs::MyArray[].last(2).should be_an_instance_of(Array)
+    ArraySpecs::MyArray[1, 2, 3].last(0).should be_an_instance_of(Array)
+    ArraySpecs::MyArray[1, 2, 3].last(1).should be_an_instance_of(Array)
+    ArraySpecs::MyArray[1, 2, 3].last(2).should be_an_instance_of(Array)
+  end
+
+  it "is not destructive" do
+    a = [1, 2, 3]
+    a.last
+    a.should == [1, 2, 3]
+    a.last(2)
+    a.should == [1, 2, 3]
+    a.last(3)
+    a.should == [1, 2, 3]
+  end
+end