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require_relative '../../spec_helper'
describe "Integer#downto [stop] when self and stop are Integers" do
it "does not yield when stop is greater than self" do
result = []
5.downto(6) { |x| result << x }
result.should == []
end
it "yields once when stop equals self" do
result = []
5.downto(5) { |x| result << x }
result.should == [5]
end
it "yields while decreasing self until it is less than stop" do
result = []
5.downto(2) { |x| result << x }
result.should == [5, 4, 3, 2]
end
it "yields while decreasing self until it less than ceil for a Float endpoint" do
result = []
9.downto(1.3) {|i| result << i}
3.downto(-1.3) {|i| result << i}
result.should == [9, 8, 7, 6, 5, 4, 3, 2, 3, 2, 1, 0, -1]
end
it "raises an ArgumentError for invalid endpoints" do
-> {1.downto("A") {|x| p x } }.should raise_error(ArgumentError)
-> {1.downto(nil) {|x| p x } }.should raise_error(ArgumentError)
end
describe "when no block is given" do
it "returns an Enumerator" do
result = []
enum = 5.downto(2)
enum.each { |i| result << i }
result.should == [5, 4, 3, 2]
end
describe "returned Enumerator" do
describe "size" do
it "raises an ArgumentError for invalid endpoints" do
enum = 1.downto("A")
-> { enum.size }.should raise_error(ArgumentError)
enum = 1.downto(nil)
-> { enum.size }.should raise_error(ArgumentError)
end
it "returns self - stop + 1" do
10.downto(5).size.should == 6
10.downto(1).size.should == 10
10.downto(0).size.should == 11
0.downto(0).size.should == 1
-3.downto(-5).size.should == 3
end
it "returns 0 when stop > self" do
4.downto(5).size.should == 0
-5.downto(0).size.should == 0
-5.downto(-3).size.should == 0
end
end
end
end
end
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