require File.expand_path('../../../spec_helper', __FILE__)
require File.expand_path('../fixtures/classes', __FILE__)

describe "Array#sort_by!" do
  it "sorts array in place by passing each element to the given block" do
    a = [-100, -2, 1, 200, 30000]
    a.sort_by!{ |e| e.to_s.size }
    a.should == [1, -2, 200, -100, 30000]
  end

  it "returns an Enumerator if not given a block" do
    (1..10).to_a.sort_by!.should be_an_instance_of(enumerator_class)
  end

  it "completes when supplied a block that always returns the same result" do
    a = [2, 3, 5, 1, 4]
    a.sort_by!{  1 }
    a.should be_an_instance_of(Array)
    a.sort_by!{  0 }
    a.should be_an_instance_of(Array)
    a.sort_by!{ -1 }
    a.should be_an_instance_of(Array)
  end

  it "raises a RuntimeError on a frozen array" do
    lambda { ArraySpecs.frozen_array.sort_by! {}}.should raise_error(RuntimeError)
  end

  it "raises a RuntimeError on an empty frozen array" do
    lambda { ArraySpecs.empty_frozen_array.sort_by! {}}.should raise_error(RuntimeError)
  end

  it "returns the specified value when it would break in the given block" do
    [1, 2, 3].sort_by!{ break :a }.should == :a
  end

  it "makes some modification even if finished sorting when it would break in the given block" do
    partially_sorted = (1..5).map{|i|
      ary = [5, 4, 3, 2, 1]
      ary.sort_by!{|x,y| break if x==i; x<=>y}
      ary
    }
    partially_sorted.any?{|ary| ary != [1, 2, 3, 4, 5]}.should be_true
  end
end
