1
0
Fork 0
mirror of https://github.com/ruby/ruby.git synced 2022-11-09 12:17:21 -05:00
ruby--ruby/spec/ruby/core/random/srand_spec.rb
eregon 1d15d5f080 Move spec/rubyspec to spec/ruby for consistency
* Other ruby implementations use the spec/ruby directory.
  [Misc #13792] [ruby-core:82287]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59979 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
2017-09-20 20:18:52 +00:00

39 lines
1.3 KiB
Ruby

require File.expand_path('../../../spec_helper', __FILE__)
describe "Random.srand" do
it "returns an arbitrary seed if .srand wasn't called previously with an argument and no argument is supplied this time" do
Random.srand # Reset to random seed in case .srand was called previously
Random.srand.should_not == Random.srand
end
it "returns the previous argument to .srand if one was given and no argument is supplied" do
Random.srand 34
Random.srand.should == 34
end
it "returns an arbitrary seed if .srand wasn't called previously with an argument and 0 is supplied this time" do
Random.srand # Reset to random seed in case .srand was called previously
Random.srand(0).should_not == Random.srand(0)
end
it "returns the previous argument to .srand if one was given and 0 is supplied" do
Random.srand 34
Random.srand(0).should == 34
end
it "seeds Random.rand such that its return value is deterministic" do
Random.srand 176542
a = 20.times.map { Random.rand }
Random.srand 176542
b = 20.times.map { Random.rand }
a.should == b
end
it "seeds Kernel.rand such that its return value is deterministic" do
Random.srand 176542
a = 20.times.map { Kernel.rand }
Random.srand 176542
b = 20.times.map { Kernel.rand }
a.should == b
end
end