require_relative '../../spec_helper'

describe "Range#size" do
  it "returns the number of elements in the range" do
    (1..16).size.should == 16
    (1...16).size.should == 15

    (1.0..16.0).size.should == 16
    (1.0...16.0).size.should == 15
    (1.0..15.9).size.should == 15
    (1.1..16.0).size.should == 15
    (1.1..15.9).size.should == 15
  end

  it "returns 0 if last is less than first" do
    (16..0).size.should == 0
    (16.0..0.0).size.should == 0
    (Float::INFINITY..0).size.should == 0
  end

  it 'returns Float::INFINITY for increasing, infinite ranges' do
    (0..Float::INFINITY).size.should == Float::INFINITY
    (-Float::INFINITY..0).size.should == Float::INFINITY
    (-Float::INFINITY..Float::INFINITY).size.should == Float::INFINITY
  end

  it 'returns Float::INFINITY for endless ranges if the start is numeric' do
    eval("(1..)").size.should == Float::INFINITY
    eval("(0.5...)").size.should == Float::INFINITY
  end

  it 'returns nil for endless ranges if the start is not numeric' do
    eval("('z'..)").size.should == nil
    eval("([]...)").size.should == nil
  end

  it 'returns Float::INFINITY for all beginless ranges' do
    (..1).size.should == Float::INFINITY
    (...0.5).size.should == Float::INFINITY
    (..nil).size.should == Float::INFINITY
    (...'o').size.should == Float::INFINITY
  end

  it "returns nil if first and last are not Numeric" do
    (:a..:z).size.should be_nil
    ('a'..'z').size.should be_nil
  end
end