require_relative '../../spec_helper' require_relative 'fixtures/classes' describe "Enumerable#max" do before :each do @e_strs = EnumerableSpecs::EachDefiner.new("333", "22", "666666", "1", "55555", "1010101010") @e_ints = EnumerableSpecs::EachDefiner.new( 333, 22, 666666, 55555, 1010101010) end it "returns the maximum element" do EnumerableSpecs::Numerous.new.max.should == 6 end it "returns the maximum element (basics cases)" do EnumerableSpecs::EachDefiner.new(55).max.should == 55 EnumerableSpecs::EachDefiner.new(11,99).max.should == 99 EnumerableSpecs::EachDefiner.new(99,11).max.should == 99 EnumerableSpecs::EachDefiner.new(2, 33, 4, 11).max.should == 33 EnumerableSpecs::EachDefiner.new(1,2,3,4,5).max.should == 5 EnumerableSpecs::EachDefiner.new(5,4,3,2,1).max.should == 5 EnumerableSpecs::EachDefiner.new(1,4,3,5,2).max.should == 5 EnumerableSpecs::EachDefiner.new(5,5,5,5,5).max.should == 5 EnumerableSpecs::EachDefiner.new("aa","tt").max.should == "tt" EnumerableSpecs::EachDefiner.new("tt","aa").max.should == "tt" EnumerableSpecs::EachDefiner.new("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 EnumerableSpecs::EachDefiner.new.max.should == nil end it "raises a NoMethodError for elements without #<=>" do lambda do EnumerableSpecs::EachDefiner.new(BasicObject.new, BasicObject.new).max end.should raise_error(NoMethodError) end it "raises an ArgumentError for incomparable elements" do lambda do EnumerableSpecs::EachDefiner.new(11,"22").max end.should raise_error(ArgumentError) lambda do EnumerableSpecs::EachDefiner.new(11,12,22,33).max{|a, b| nil} end.should raise_error(ArgumentError) end context "when passed a block" do it "returns the maximum element" do EnumerableSpecs::EachDefiner.new("2","33","4","11").max {|a,b| a <=> b }.should == "4" EnumerableSpecs::EachDefiner.new( 2 , 33 , 4 , 11 ).max {|a,b| a <=> b }.should == 33 EnumerableSpecs::EachDefiner.new("2","33","4","11").max {|a,b| b <=> a }.should == "11" EnumerableSpecs::EachDefiner.new( 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 end it "returns the maximum for enumerables that contain nils" do arr = EnumerableSpecs::Numerous.new(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 = EnumerableSpecs::YieldsMulti.new multi.max.should == [6, 7, 8, 9] end context "when called with an argument n" do context "without a block" do it "returns an array containing the maximum n elements" do result = @e_ints.max(2) result.should == [1010101010, 666666] end end context "with a block" do it "returns an array containing the maximum n elements" do result = @e_ints.max(2) { |a, b| a * 2 <=> b * 2 } result.should == [1010101010, 666666] end end context "on a enumerable of length x where x < n" do it "returns an array containing the maximum n elements of length x" do result = @e_ints.max(500) result.length.should == 5 end end context "that is negative" do it "raises an ArgumentError" do lambda { @e_ints.max(-1) }.should raise_error(ArgumentError) end end end context "that is nil" do it "returns the maximum element" do @e_ints.max(nil).should == 1010101010 end end end