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diff --git a/spec/rubyspec/core/array/max_spec.rb b/spec/rubyspec/core/array/max_spec.rb
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+++ b/spec/rubyspec/core/array/max_spec.rb
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+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "Array#max" do
+  it "returns nil with no values" do
+    [].max.should == nil
+  end
+
+  it "returns only element in one element array" do
+    [1].max.should == 1
+  end
+
+  it "returns largest value with multiple elements" do
+    [1,2].max.should == 2
+    [2,1].max.should == 2
+  end
+
+  describe "given a block with one argument" do
+    it "yields in turn the last length-1 values from the array" do
+      ary = []
+      result = [1,2,3,4,5].max {|x| ary << x; x}
+
+      ary.should == [2,3,4,5]
+      result.should == 5
+    end
+  end
+end
+
+# From Enumerable#max, copied for better readability
+describe "Array#max" do
+  before :each do
+    @a = [2, 4, 6, 8, 10]
+
+    @e_strs = ["333", "22", "666666", "1", "55555", "1010101010"]
+    @e_ints = [333,   22,   666666,   55555, 1010101010]
+  end
+
+  it "max should return the maximum element" do
+    [18, 42].max.should == 42
+    [2, 5, 3, 6, 1, 4].max.should == 6
+  end
+
+  it "returns the maximum element (basics cases)" do
+    [55].max.should == 55
+
+    [11,99].max.should == 99
+    [99,11].max.should == 99
+    [2, 33, 4, 11].max.should == 33
+
+    [1,2,3,4,5].max.should == 5
+    [5,4,3,2,1].max.should == 5
+    [1,4,3,5,2].max.should == 5
+    [5,5,5,5,5].max.should == 5
+
+    ["aa","tt"].max.should == "tt"
+    ["tt","aa"].max.should == "tt"
+    ["2","33","4","11"].max.should == "4"
+
+    @e_strs.max.should == "666666"
+    @e_ints.max.should == 1010101010
+  end
+
+  it "returns nil for an empty Enumerable" do
+    [].max.should == nil
+  end
+
+  it "raises a NoMethodError for elements without #<=>" do
+    lambda do
+      [BasicObject.new, BasicObject.new].max
+    end.should raise_error(NoMethodError)
+  end
+
+  it "raises an ArgumentError for incomparable elements" do
+    lambda do
+      [11,"22"].max
+    end.should raise_error(ArgumentError)
+    lambda do
+      [11,12,22,33].max{|a, b| nil}
+    end.should raise_error(ArgumentError)
+  end
+
+  it "returns the maximum element (with block)" do
+    # with a block
+    ["2","33","4","11"].max {|a,b| a <=> b }.should == "4"
+    [ 2 , 33 , 4 , 11 ].max {|a,b| a <=> b }.should == 33
+
+    ["2","33","4","11"].max {|a,b| b <=> a }.should == "11"
+    [ 2 , 33 , 4 , 11 ].max {|a,b| b <=> a }.should == 2
+
+    @e_strs.max {|a,b| a.length <=> b.length }.should == "1010101010"
+
+    @e_strs.max {|a,b| a <=> b }.should == "666666"
+    @e_strs.max {|a,b| a.to_i <=> b.to_i }.should == "1010101010"
+
+    @e_ints.max {|a,b| a <=> b }.should == 1010101010
+    @e_ints.max {|a,b| a.to_s <=> b.to_s }.should == 666666
+  end
+
+  it "returns the minimum for enumerables that contain nils" do
+    arr = [nil, nil, true]
+    arr.max { |a, b|
+      x = a.nil? ? 1 : a ? 0 : -1
+      y = b.nil? ? 1 : b ? 0 : -1
+      x <=> y
+    }.should == nil
+  end
+
+  it "gathers whole arrays as elements when each yields multiple" do
+    multi = [[1,2], [3,4,5], [6,7,8,9]]
+    multi.max.should == [6, 7, 8, 9]
+  end
+
+end