Revert "SortedSet was removed at a3db08d7b6ff119223f77e3df00b4f6deac971e2"

* This reverts commit b06ffce4ae.
* Do not revert specs, wrap them with `ruby_version_is` (tool for that in next commit).

spec/ruby/library/set/sortedset/add_spec.rb

@@ -0,0 +1,39 @@
+require_relative '../../../spec_helper'
+require 'set'
+require_relative 'shared/add'
+
+describe "SortedSet#add" do
+  it_behaves_like :sorted_set_add, :add
+
+  it "takes only values which responds <=>" do
+    obj = mock('no_comparison_operator')
+    obj.stub!(:respond_to?).with(:<=>).and_return(false)
+    -> { SortedSet["hello"].add(obj) }.should raise_error(ArgumentError)
+  end
+
+  it "raises on incompatible <=> comparison" do
+    # Use #to_a here as elements are sorted only when needed.
+    # Therefore the <=> incompatibility is only noticed on sorting.
+    -> { SortedSet['1', '2'].add(3).to_a }.should raise_error(ArgumentError)
+  end
+end
+
+describe "SortedSet#add?" do
+  before :each do
+    @set = SortedSet.new
+  end
+
+  it "adds the passed Object to self" do
+    @set.add?("cat")
+    @set.should include("cat")
+  end
+
+  it "returns self when the Object has not yet been added to self" do
+    @set.add?("cat").should equal(@set)
+  end
+
+  it "returns nil when the Object has already been added to self" do
+    @set.add?("cat")
+    @set.add?("cat").should be_nil
+  end
+end

spec/ruby/library/set/sortedset/append_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require 'set'
+require_relative 'shared/add'
+
+describe "SortedSet#<<" do
+  it_behaves_like :sorted_set_add, :<<
+end

spec/ruby/library/set/sortedset/case_equality_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require_relative 'shared/include'
+require 'set'
+
+describe "SortedSet#===" do
+  it_behaves_like :sorted_set_include, :===
+end

spec/ruby/library/set/sortedset/classify_spec.rb

@@ -0,0 +1,27 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#classify" do
+  before :each do
+    @set = SortedSet["one", "two", "three", "four"]
+  end
+
+  it "yields each Object in self in sorted order" do
+    res = []
+    @set.classify { |x| res << x }
+    res.should == ["one", "two", "three", "four"].sort
+  end
+
+  it "returns an Enumerator when passed no block" do
+    enum = @set.classify
+    enum.should be_an_instance_of(Enumerator)
+
+    classified = enum.each { |x| x.length }
+    classified.should == { 3 => SortedSet["one", "two"], 4 => SortedSet["four"], 5 => SortedSet["three"] }
+  end
+
+  it "classifies the Objects in self based on the block's return value" do
+    classified = @set.classify { |x| x.length }
+    classified.should == { 3 => SortedSet["one", "two"], 4 => SortedSet["four"], 5 => SortedSet["three"] }
+  end
+end

spec/ruby/library/set/sortedset/clear_spec.rb

@@ -0,0 +1,17 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#clear" do
+  before :each do
+    @set = SortedSet["one", "two", "three", "four"]
+  end
+
+  it "removes all elements from self" do
+    @set.clear
+    @set.should be_empty
+  end
+
+  it "returns self" do
+    @set.clear.should equal(@set)
+  end
+end

spec/ruby/library/set/sortedset/collect_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require 'set'
+require_relative 'shared/collect'
+
+describe "SortedSet#collect!" do
+  it_behaves_like :sorted_set_collect_bang, :collect!
+end

spec/ruby/library/set/sortedset/constructor_spec.rb

@@ -0,0 +1,15 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet[]" do
+  it "returns a new SortedSet populated with the passed Objects" do
+    set = SortedSet[1, 2, 3]
+
+    set.instance_of?(SortedSet).should be_true
+    set.size.should eql(3)
+
+    set.should include(1)
+    set.should include(2)
+    set.should include(3)
+  end
+end

spec/ruby/library/set/sortedset/delete_if_spec.rb

@@ -0,0 +1,38 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#delete_if" do
+  before :each do
+    @set = SortedSet["one", "two", "three"]
+  end
+
+  it "yields each Object in self in sorted order" do
+    ret = []
+    @set.delete_if { |x| ret << x }
+    ret.should == ["one", "two", "three"].sort
+  end
+
+  it "deletes every element from self for which the passed block returns true" do
+    @set.delete_if { |x| x.size == 3 }
+    @set.size.should eql(1)
+
+    @set.should_not include("one")
+    @set.should_not include("two")
+    @set.should include("three")
+  end
+
+  it "returns self" do
+    @set.delete_if { |x| x }.should equal(@set)
+  end
+
+  it "returns an Enumerator when passed no block" do
+    enum = @set.delete_if
+    enum.should be_an_instance_of(Enumerator)
+
+    enum.each { |x| x.size == 3 }
+
+    @set.should_not include("one")
+    @set.should_not include("two")
+    @set.should include("three")
+  end
+end

spec/ruby/library/set/sortedset/delete_spec.rb

@@ -0,0 +1,37 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#delete" do
+  before :each do
+    @set = SortedSet["a", "b", "c"]
+  end
+
+  it "deletes the passed Object from self" do
+    @set.delete("a")
+    @set.should_not include("a")
+  end
+
+  it "returns self" do
+    @set.delete("a").should equal(@set)
+    @set.delete("x").should equal(@set)
+  end
+end
+
+describe "SortedSet#delete?" do
+  before :each do
+    @set = SortedSet["a", "b", "c"]
+  end
+
+  it "deletes the passed Object from self" do
+    @set.delete?("a")
+    @set.should_not include("a")
+  end
+
+  it "returns self when the passed Object is in self" do
+    @set.delete?("a").should equal(@set)
+  end
+
+  it "returns nil when the passed Object is not in self" do
+    @set.delete?("x").should be_nil
+  end
+end

spec/ruby/library/set/sortedset/difference_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require 'set'
+require_relative 'shared/difference'
+
+describe "SortedSet#difference" do
+  it_behaves_like :sorted_set_difference, :difference
+end

spec/ruby/library/set/sortedset/divide_spec.rb

@@ -0,0 +1,34 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#divide" do
+  it "divides self into a set of subsets based on the blocks return values" do
+    set = SortedSet["one", "two", "three", "four", "five"].divide { |x| x.length }
+    set.map { |x| x.to_a }.to_a.sort.should == [["five", "four"], ["one", "two"], ["three"]]
+  end
+
+  it "yields each Object in self in sorted order" do
+    ret = []
+    SortedSet["one", "two", "three", "four", "five"].divide { |x| ret << x }
+    ret.should == ["one", "two", "three", "four", "five"].sort
+  end
+
+  # BUG: Does not raise a LocalJumpError, but a NoMethodError
+  #
+  # it "raises a LocalJumpError when not passed a block" do
+  #   lambda { SortedSet[1].divide }.should raise_error(LocalJumpError)
+  # end
+end
+
+describe "SortedSet#divide when passed a block with an arity of 2" do
+  it "divides self into a set of subsets based on the blocks return values" do
+    set = SortedSet[1, 3, 4, 6, 9, 10, 11].divide { |x, y| (x - y).abs == 1 }
+    set.map { |x| x.to_a }.to_a.sort.should == [[1], [3, 4], [6], [9, 10, 11]]
+  end
+
+  it "yields each two Objects to the block" do
+    ret = []
+    SortedSet[1, 2].divide { |x, y| ret << [x, y] }
+    ret.should == [[1, 1], [1, 2], [2, 1], [2, 2]]
+  end
+end

spec/ruby/library/set/sortedset/each_spec.rb

@@ -0,0 +1,26 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#each" do
+  before :each do
+    @set = SortedSet[1, 2, 3]
+  end
+
+  it "yields each Object in self in sorted order" do
+    ret = []
+    SortedSet["one", "two", "three"].each { |x| ret << x }
+    ret.should == ["one", "two", "three"].sort
+  end
+
+  it "returns self" do
+    @set.each { |x| x }.should equal(@set)
+  end
+
+  it "returns an Enumerator when not passed a block" do
+    enum = @set.each
+
+    ret = []
+    enum.each { |x| ret << x }
+    ret.sort.should == [1, 2, 3]
+  end
+end

spec/ruby/library/set/sortedset/empty_spec.rb

@@ -0,0 +1,10 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#empty?" do
+  it "returns true if self is empty" do
+    SortedSet[].empty?.should be_true
+    SortedSet[1].empty?.should be_false
+    SortedSet[1,2,3].empty?.should be_false
+  end
+end

spec/ruby/library/set/sortedset/eql_spec.rb

@@ -0,0 +1,16 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#eql?" do
+  it "returns true when the passed argument is a SortedSet and contains the same elements" do
+    SortedSet[].should eql(SortedSet[])
+    SortedSet[1, 2, 3].should eql(SortedSet[1, 2, 3])
+    SortedSet[1, 2, 3].should eql(SortedSet[3, 2, 1])
+
+#    SortedSet["a", :b, ?c].should eql(SortedSet[?c, :b, "a"])
+
+    SortedSet[1, 2, 3].should_not eql(SortedSet[1.0, 2, 3])
+    SortedSet[1, 2, 3].should_not eql(SortedSet[2, 3])
+    SortedSet[1, 2, 3].should_not eql(SortedSet[])
+  end
+end

spec/ruby/library/set/sortedset/equal_value_spec.rb

@@ -0,0 +1,13 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#==" do
+  it "returns true when the passed Object is a SortedSet and self and the Object contain the same elements" do
+    SortedSet[].should == SortedSet[]
+    SortedSet[1, 2, 3].should == SortedSet[1, 2, 3]
+    SortedSet["1", "2", "3"].should == SortedSet["1", "2", "3"]
+
+    SortedSet[1, 2, 3].should_not == SortedSet[1.0, 2, 3]
+    SortedSet[1, 2, 3].should_not == [1, 2, 3]
+  end
+end

spec/ruby/library/set/sortedset/exclusion_spec.rb

@@ -0,0 +1,18 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#^" do
+  before :each do
+    @set = SortedSet[1, 2, 3, 4]
+  end
+
+  it "returns a new SortedSet containing elements that are not in both self and the passed Enumerable" do
+    (@set ^ SortedSet[3, 4, 5]).should == SortedSet[1, 2, 5]
+    (@set ^ [3, 4, 5]).should == SortedSet[1, 2, 5]
+  end
+
+  it "raises an ArgumentError when passed a non-Enumerable" do
+    -> { @set ^ 3 }.should raise_error(ArgumentError)
+    -> { @set ^ Object.new }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/library/set/sortedset/filter_spec.rb

@@ -0,0 +1,9 @@
+require_relative '../../../spec_helper'
+require_relative 'shared/select'
+require 'set'
+
+ruby_version_is "2.6" do
+  describe "SortedSet#filter!" do
+    it_behaves_like :sorted_set_select_bang, :filter!
+  end
+end

spec/ruby/library/set/sortedset/flatten_merge_spec.rb

@@ -0,0 +1,8 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#flatten_merge" do
+  it "is protected" do
+    SortedSet.should have_protected_instance_method("flatten_merge")
+  end
+end

spec/ruby/library/set/sortedset/flatten_spec.rb

@@ -0,0 +1,44 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+# Note: Flatten make little sens on sorted sets, because SortedSets are not (by default)
+# comparable. For a SortedSet to be both valid and nested, we need to define a comparison operator:
+module SortedSet_FlattenSpecs
+  class ComparableSortedSet < SortedSet
+    def <=>(other)
+      return puts "#{other} vs #{self}" unless other.is_a?(ComparableSortedSet)
+      to_a <=> other.to_a
+    end
+  end
+end
+
+describe "SortedSet#flatten" do
+  it "returns a copy of self with each included SortedSet flattened" do
+    klass = SortedSet_FlattenSpecs::ComparableSortedSet
+    set = klass[klass[1,2], klass[3,4], klass[5,6,7], klass[8]]
+    flattened_set = set.flatten
+
+    flattened_set.should_not equal(set)
+    flattened_set.should == klass[1, 2, 3, 4, 5, 6, 7, 8]
+  end
+end
+
+describe "SortedSet#flatten!" do
+  it "flattens self" do
+    klass = SortedSet_FlattenSpecs::ComparableSortedSet
+    set = klass[klass[1,2], klass[3,4], klass[5,6,7], klass[8]]
+    set.flatten!
+    set.should == klass[1, 2, 3, 4, 5, 6, 7, 8]
+  end
+
+  it "returns self when self was modified" do
+    klass = SortedSet_FlattenSpecs::ComparableSortedSet
+    set = klass[klass[1,2], klass[3,4]]
+    set.flatten!.should equal(set)
+  end
+
+  it "returns nil when self was not modified" do
+    set = SortedSet[1, 2, 3, 4]
+    set.flatten!.should be_nil
+  end
+end

spec/ruby/library/set/sortedset/hash_spec.rb

@@ -0,0 +1,13 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#hash" do
+  it "is static" do
+    SortedSet[].hash.should == SortedSet[].hash
+    SortedSet[1, 2, 3].hash.should == SortedSet[1, 2, 3].hash
+    SortedSet["a", "b", "c"].hash.should == SortedSet["c", "b", "a"].hash
+
+    SortedSet[].hash.should_not == SortedSet[1, 2, 3].hash
+    SortedSet[1, 2, 3].hash.should_not == SortedSet["a", "b", "c"].hash
+  end
+end

spec/ruby/library/set/sortedset/include_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require_relative 'shared/include'
+require 'set'
+
+describe "SortedSet#include?" do
+  it_behaves_like :sorted_set_include, :include?
+end

spec/ruby/library/set/sortedset/initialize_spec.rb

@@ -0,0 +1,30 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#initialize" do
+  it "is private" do
+    SortedSet.should have_private_instance_method("initialize")
+  end
+
+  it "adds all elements of the passed Enumerable to self" do
+    s = SortedSet.new([1, 2, 3])
+    s.size.should eql(3)
+    s.should include(1)
+    s.should include(2)
+    s.should include(3)
+  end
+
+  it "preprocesses all elements by a passed block before adding to self" do
+    s = SortedSet.new([1, 2, 3]) { |x| x * x }
+    s.size.should eql(3)
+    s.should include(1)
+    s.should include(4)
+    s.should include(9)
+  end
+
+  it "raises on incompatible <=> comparison" do
+    # Use #to_a here as elements are sorted only when needed.
+    # Therefore the <=> incompatibility is only noticed on sorting.
+    -> { SortedSet.new(['00', nil]).to_a }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/library/set/sortedset/inspect_spec.rb

@@ -0,0 +1,10 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#inspect" do
+  it "returns a String representation of self" do
+    SortedSet[].inspect.should be_kind_of(String)
+    SortedSet[1, 2, 3].inspect.should be_kind_of(String)
+    SortedSet["1", "2", "3"].inspect.should be_kind_of(String)
+  end
+end

spec/ruby/library/set/sortedset/intersection_spec.rb

@@ -0,0 +1,11 @@
+require_relative '../../../spec_helper'
+require_relative 'shared/intersection'
+require 'set'
+
+describe "SortedSet#intersection" do
+  it_behaves_like :sorted_set_intersection, :intersection
+end
+
+describe "SortedSet#&" do
+  it_behaves_like :sorted_set_intersection, :&
+end

spec/ruby/library/set/sortedset/keep_if_spec.rb

@@ -0,0 +1,31 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#keep_if" do
+  before :each do
+    @set = SortedSet["one", "two", "three"]
+  end
+
+  it "yields each Object in self in sorted order" do
+    ret = []
+    @set.keep_if { |x| ret << x }
+    ret.should == ["one", "two", "three"].sort
+  end
+
+  it "keeps every element from self for which the passed block returns true" do
+    @set.keep_if { |x| x.size != 3 }
+    @set.to_a.should == ["three"]
+  end
+
+  it "returns self" do
+    @set.keep_if {}.should equal(@set)
+  end
+
+  it "returns an Enumerator when passed no block" do
+    enum = @set.keep_if
+    enum.should be_an_instance_of(Enumerator)
+
+    enum.each { |x| x.size != 3 }
+    @set.to_a.should == ["three"]
+  end
+end

spec/ruby/library/set/sortedset/length_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require_relative 'shared/length'
+require 'set'
+
+describe "SortedSet#length" do
+  it_behaves_like :sorted_set_length, :length
+end

spec/ruby/library/set/sortedset/map_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require 'set'
+require_relative 'shared/collect'
+
+describe "SortedSet#map!" do
+  it_behaves_like :sorted_set_collect_bang, :map!
+end

spec/ruby/library/set/sortedset/member_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require_relative 'shared/include'
+require 'set'
+
+describe "SortedSet#member?" do
+  it_behaves_like :sorted_set_include, :member?
+end

spec/ruby/library/set/sortedset/merge_spec.rb

@@ -0,0 +1,19 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#merge" do
+  it "adds the elements of the passed Enumerable to self" do
+    SortedSet["a", "b"].merge(SortedSet["b", "c", "d"]).should == SortedSet["a", "b", "c", "d"]
+    SortedSet[1, 2].merge([3, 4]).should == SortedSet[1, 2, 3, 4]
+  end
+
+  it "returns self" do
+    set = SortedSet[1, 2]
+    set.merge([3, 4]).should equal(set)
+  end
+
+  it "raises an ArgumentError when passed a non-Enumerable" do
+    -> { SortedSet[1, 2].merge(1) }.should raise_error(ArgumentError)
+    -> { SortedSet[1, 2].merge(Object.new) }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/library/set/sortedset/minus_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require 'set'
+require_relative 'shared/difference'
+
+describe "SortedSet#-" do
+  it_behaves_like :sorted_set_difference, :-
+end

spec/ruby/library/set/sortedset/plus_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require_relative 'shared/union'
+require 'set'
+
+describe "SortedSet#+" do
+  it_behaves_like :sorted_set_union, :+
+end

spec/ruby/library/set/sortedset/pretty_print_cycle_spec.rb

@@ -0,0 +1,10 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#pretty_print_cycle" do
+  it "passes the 'pretty print' representation of a self-referencing SortedSet to the pretty print writer" do
+    pp = mock("PrettyPrint")
+    pp.should_receive(:text).with("#<SortedSet: {...}>")
+    SortedSet[1, 2, 3].pretty_print_cycle(pp)
+  end
+end

spec/ruby/library/set/sortedset/pretty_print_spec.rb

@@ -0,0 +1,17 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#pretty_print" do
+  it "passes the 'pretty print' representation of self to the pretty print writer" do
+    pp = mock("PrettyPrint")
+    set = SortedSet[1, 2, 3]
+
+    pp.should_receive(:text).with("#<SortedSet: {")
+    pp.should_receive(:text).with("}>")
+
+    pp.should_receive(:nest).with(1).and_yield
+    pp.should_receive(:seplist).with(set)
+
+    set.pretty_print(pp)
+  end
+end

spec/ruby/library/set/sortedset/proper_subset_spec.rb

@@ -0,0 +1,33 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#proper_subset?" do
+  before :each do
+    @set = SortedSet[1, 2, 3, 4]
+  end
+
+  it "returns true if passed a SortedSet that self is a proper subset of" do
+    SortedSet[].proper_subset?(@set).should be_true
+    SortedSet[].proper_subset?(SortedSet[1, 2, 3]).should be_true
+    SortedSet[].proper_subset?(SortedSet["a", "b", "c"]).should be_true
+
+    SortedSet[1, 2, 3].proper_subset?(@set).should be_true
+    SortedSet[1, 3].proper_subset?(@set).should be_true
+    SortedSet[1, 2].proper_subset?(@set).should be_true
+    SortedSet[1].proper_subset?(@set).should be_true
+
+    SortedSet[5].proper_subset?(@set).should be_false
+    SortedSet[1, 5].proper_subset?(@set).should be_false
+    SortedSet["test"].proper_subset?(@set).should be_false
+
+    @set.proper_subset?(@set).should be_false
+    SortedSet[].proper_subset?(SortedSet[]).should be_false
+  end
+
+  it "raises an ArgumentError when passed a non-SortedSet" do
+    -> { SortedSet[].proper_subset?([]) }.should raise_error(ArgumentError)
+    -> { SortedSet[].proper_subset?(1) }.should raise_error(ArgumentError)
+    -> { SortedSet[].proper_subset?("test") }.should raise_error(ArgumentError)
+    -> { SortedSet[].proper_subset?(Object.new) }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/library/set/sortedset/proper_superset_spec.rb

@@ -0,0 +1,33 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#proper_superset?" do
+  before :each do
+    @set = SortedSet[1, 2, 3, 4]
+  end
+
+  it "returns true if passed a SortedSet that self is a proper superset of" do
+    @set.proper_superset?(SortedSet[]).should be_true
+    SortedSet[1, 2, 3].proper_superset?(SortedSet[]).should be_true
+    SortedSet["a", "b", "c"].proper_superset?(SortedSet[]).should be_true
+
+    @set.proper_superset?(SortedSet[1, 2, 3]).should be_true
+    @set.proper_superset?(SortedSet[1, 3]).should be_true
+    @set.proper_superset?(SortedSet[1, 2]).should be_true
+    @set.proper_superset?(SortedSet[1]).should be_true
+
+    @set.proper_superset?(SortedSet[5]).should be_false
+    @set.proper_superset?(SortedSet[1, 5]).should be_false
+    @set.proper_superset?(SortedSet["test"]).should be_false
+
+    @set.proper_superset?(@set).should be_false
+    SortedSet[].proper_superset?(SortedSet[]).should be_false
+  end
+
+  it "raises an ArgumentError when passed a non-SortedSet" do
+    -> { SortedSet[].proper_superset?([]) }.should raise_error(ArgumentError)
+    -> { SortedSet[].proper_superset?(1) }.should raise_error(ArgumentError)
+    -> { SortedSet[].proper_superset?("test") }.should raise_error(ArgumentError)
+    -> { SortedSet[].proper_superset?(Object.new) }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/library/set/sortedset/reject_spec.rb

@@ -0,0 +1,42 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#reject!" do
+  before :each do
+    @set = SortedSet["one", "two", "three"]
+  end
+
+  it "yields each Object in self in sorted order" do
+    res = []
+    @set.reject! { |x| res << x }
+    res.should == ["one", "two", "three"].sort
+  end
+
+  it "deletes every element from self for which the passed block returns true" do
+    @set.reject! { |x| x.size == 3 }
+    @set.size.should eql(1)
+
+    @set.should_not include("one")
+    @set.should_not include("two")
+    @set.should include("three")
+  end
+
+  it "returns self when self was modified" do
+    @set.reject! { |x| true }.should equal(@set)
+  end
+
+  it "returns nil when self was not modified" do
+    @set.reject! { |x| false }.should be_nil
+  end
+
+  it "returns an Enumerator when passed no block" do
+    enum = @set.reject!
+    enum.should be_an_instance_of(Enumerator)
+
+    enum.each { |x| x.size == 3 }
+
+    @set.should_not include("one")
+    @set.should_not include("two")
+    @set.should include("three")
+  end
+end

spec/ruby/library/set/sortedset/replace_spec.rb

@@ -0,0 +1,17 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#replace" do
+  before :each do
+    @set = SortedSet["a", "b", "c"]
+  end
+
+  it "replaces the contents with other and returns self" do
+    @set.replace(SortedSet[1, 2, 3]).should == @set
+    @set.should == SortedSet[1, 2, 3]
+  end
+
+  it "accepts any enumerable as other" do
+    @set.replace([1, 2, 3]).should == SortedSet[1, 2, 3]
+  end
+end

spec/ruby/library/set/sortedset/select_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require_relative 'shared/select'
+require 'set'
+
+describe "SortedSet#select!" do
+  it_behaves_like :sorted_set_select_bang, :select!
+end

spec/ruby/library/set/sortedset/shared/add.rb

@@ -0,0 +1,14 @@
+describe :sorted_set_add, shared: true do
+  before :each do
+    @set = SortedSet.new
+  end
+
+  it "adds the passed Object to self" do
+    @set.send(@method, "dog")
+    @set.should include("dog")
+  end
+
+  it "returns self" do
+    @set.send(@method, "dog").should equal(@set)
+  end
+end

spec/ruby/library/set/sortedset/shared/collect.rb

@@ -0,0 +1,20 @@
+describe :sorted_set_collect_bang, shared: true do
+  before :each do
+    @set = SortedSet[1, 2, 3, 4, 5]
+  end
+
+  it "yields each Object in self in sorted order" do
+    res = []
+    SortedSet["one", "two", "three"].send(@method) { |x| res << x; x }
+    res.should == ["one", "two", "three"].sort
+  end
+
+  it "returns self" do
+    @set.send(@method) { |x| x }.should equal(@set)
+  end
+
+  it "replaces self with the return values of the block" do
+    @set.send(@method) { |x| x * 2 }
+    @set.should == SortedSet[2, 4, 6, 8, 10]
+  end
+end

spec/ruby/library/set/sortedset/shared/difference.rb

@@ -0,0 +1,15 @@
+describe :sorted_set_difference, shared: true do
+  before :each do
+    @set = SortedSet["a", "b", "c"]
+  end
+
+  it "returns a new SortedSet containing self's elements excluding the elements in the passed Enumerable" do
+    @set.send(@method, SortedSet["a", "b"]).should == SortedSet["c"]
+    @set.send(@method, ["b", "c"]).should == SortedSet["a"]
+  end
+
+  it "raises an ArgumentError when passed a non-Enumerable" do
+    -> { @set.send(@method, 1) }.should raise_error(ArgumentError)
+    -> { @set.send(@method, Object.new) }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/library/set/sortedset/shared/include.rb

@@ -0,0 +1,7 @@
+describe :sorted_set_include, shared: true do
+  it "returns true when self contains the passed Object" do
+    set = SortedSet["a", "b", "c"]
+    set.send(@method, "a").should be_true
+    set.send(@method, "e").should be_false
+  end
+end

spec/ruby/library/set/sortedset/shared/intersection.rb

@@ -0,0 +1,15 @@
+describe :sorted_set_intersection, shared: true do
+  before :each do
+    @set = SortedSet["a", "b", "c"]
+  end
+
+  it "returns a new SortedSet containing only elements shared by self and the passed Enumerable" do
+    @set.send(@method, SortedSet["b", "c", "d", "e"]).should == SortedSet["b", "c"]
+    @set.send(@method, ["b", "c", "d"]).should == SortedSet["b", "c"]
+  end
+
+  it "raises an ArgumentError when passed a non-Enumerable" do
+    -> { @set.send(@method, 1) }.should raise_error(ArgumentError)
+    -> { @set.send(@method, Object.new) }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/library/set/sortedset/shared/length.rb

@@ -0,0 +1,6 @@
+describe :sorted_set_length, shared: true do
+  it "returns the number of elements in the set" do
+    set = SortedSet["a", "b", "c"]
+    set.send(@method).should == 3
+  end
+end

spec/ruby/library/set/sortedset/shared/select.rb

@@ -0,0 +1,35 @@
+require_relative '../../../../spec_helper'
+require 'set'
+
+describe :sorted_set_select_bang, shared: true do
+  before :each do
+    @set = SortedSet["one", "two", "three"]
+  end
+
+  it "yields each Object in self in sorted order" do
+    res = []
+    @set.send(@method) { |x| res << x }
+    res.should == ["one", "two", "three"].sort
+  end
+
+  it "keeps every element from self for which the passed block returns true" do
+    @set.send(@method) { |x| x.size != 3 }
+    @set.to_a.should == ["three"]
+  end
+
+  it "returns self when self was modified" do
+    @set.send(@method) { false }.should equal(@set)
+  end
+
+  it "returns nil when self was not modified" do
+    @set.send(@method) { true }.should be_nil
+  end
+
+  it "returns an Enumerator when passed no block" do
+    enum = @set.send(@method)
+    enum.should be_an_instance_of(Enumerator)
+
+    enum.each { |x| x.size != 3 }
+    @set.to_a.should == ["three"]
+  end
+end

spec/ruby/library/set/sortedset/shared/union.rb

@@ -0,0 +1,15 @@
+describe :sorted_set_union, shared: true do
+  before :each do
+    @set = SortedSet["a", "b", "c"]
+  end
+
+  it "returns a new SortedSet containing all elements of self and the passed Enumerable" do
+    @set.send(@method, SortedSet["b", "d", "e"]).should == SortedSet["a", "b", "c", "d", "e"]
+    @set.send(@method, ["b", "e"]).should == SortedSet["a", "b", "c", "e"]
+  end
+
+  it "raises an ArgumentError when passed a non-Enumerable" do
+    -> { @set.send(@method, 1) }.should raise_error(ArgumentError)
+    -> { @set.send(@method, Object.new) }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/library/set/sortedset/size_spec.rb

@@ -0,0 +1,7 @@
+require_relative '../../../spec_helper'
+require_relative 'shared/length'
+require 'set'
+
+describe "SortedSet#size" do
+  it_behaves_like :sorted_set_length, :size
+end

spec/ruby/library/set/sortedset/subset_spec.rb

@@ -0,0 +1,33 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#subset?" do
+  before :each do
+    @set = SortedSet[1, 2, 3, 4]
+  end
+
+  it "returns true if passed a SortedSet that is equal to self or self is a subset of" do
+    @set.subset?(@set).should be_true
+    SortedSet[].subset?(SortedSet[]).should be_true
+
+    SortedSet[].subset?(@set).should be_true
+    SortedSet[].subset?(SortedSet[1, 2, 3]).should be_true
+    SortedSet[].subset?(SortedSet["a", "b", "c"]).should be_true
+
+    SortedSet[1, 2, 3].subset?(@set).should be_true
+    SortedSet[1, 3].subset?(@set).should be_true
+    SortedSet[1, 2].subset?(@set).should be_true
+    SortedSet[1].subset?(@set).should be_true
+
+    SortedSet[5].subset?(@set).should be_false
+    SortedSet[1, 5].subset?(@set).should be_false
+    SortedSet["test"].subset?(@set).should be_false
+  end
+
+  it "raises an ArgumentError when passed a non-SortedSet" do
+    -> { SortedSet[].subset?([]) }.should raise_error(ArgumentError)
+    -> { SortedSet[].subset?(1) }.should raise_error(ArgumentError)
+    -> { SortedSet[].subset?("test") }.should raise_error(ArgumentError)
+    -> { SortedSet[].subset?(Object.new) }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/library/set/sortedset/subtract_spec.rb

@@ -0,0 +1,17 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#subtract" do
+  before :each do
+    @set = SortedSet["a", "b", "c"]
+  end
+
+  it "deletes any elements contained in other and returns self" do
+    @set.subtract(SortedSet["b", "c"]).should == @set
+    @set.should == SortedSet["a"]
+  end
+
+  it "accepts any enumerable as other" do
+    @set.subtract(["c"]).should == SortedSet["a", "b"]
+  end
+end

spec/ruby/library/set/sortedset/superset_spec.rb

@@ -0,0 +1,33 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#superset?" do
+  before :each do
+    @set = SortedSet[1, 2, 3, 4]
+  end
+
+  it "returns true if passed a SortedSet that equals self or self is a proper superset of" do
+    @set.superset?(@set).should be_true
+    SortedSet[].superset?(SortedSet[]).should be_true
+
+    @set.superset?(SortedSet[]).should be_true
+    SortedSet[1, 2, 3].superset?(SortedSet[]).should be_true
+    SortedSet["a", "b", "c"].superset?(SortedSet[]).should be_true
+
+    @set.superset?(SortedSet[1, 2, 3]).should be_true
+    @set.superset?(SortedSet[1, 3]).should be_true
+    @set.superset?(SortedSet[1, 2]).should be_true
+    @set.superset?(SortedSet[1]).should be_true
+
+    @set.superset?(SortedSet[5]).should be_false
+    @set.superset?(SortedSet[1, 5]).should be_false
+    @set.superset?(SortedSet["test"]).should be_false
+  end
+
+  it "raises an ArgumentError when passed a non-SortedSet" do
+    -> { SortedSet[].superset?([]) }.should raise_error(ArgumentError)
+    -> { SortedSet[].superset?(1) }.should raise_error(ArgumentError)
+    -> { SortedSet[].superset?("test") }.should raise_error(ArgumentError)
+    -> { SortedSet[].superset?(Object.new) }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/library/set/sortedset/to_a_spec.rb

@@ -0,0 +1,17 @@
+require_relative '../../../spec_helper'
+require 'set'
+
+describe "SortedSet#to_a" do
+  it "returns an array containing elements" do
+    set = SortedSet.new [1, 2, 3]
+    set.to_a.should == [1, 2, 3]
+  end
+
+  it "returns a sorted array containing elements" do
+    set = SortedSet[2, 3, 1]
+    set.to_a.should == [1, 2, 3]
+
+    set = SortedSet.new [5, 6, 4, 4]
+    set.to_a.should == [4, 5, 6]
+  end
+end

spec/ruby/library/set/sortedset/union_spec.rb

@@ -0,0 +1,11 @@
+require_relative '../../../spec_helper'
+require_relative 'shared/union'
+require 'set'
+
+describe "SortedSet#union" do
+  it_behaves_like :sorted_set_union, :union
+end
+
+describe "SortedSet#|" do
+  it_behaves_like :sorted_set_union, :|
+end