ruby--ruby/spec/ruby/core/kernel/proc_spec.rb

require_relative '../../spec_helper'
require_relative 'fixtures/classes'
require_relative 'shared/lambda'

# The functionality of Proc objects is specified in core/proc

describe "Kernel.proc" do
  it "is a private method" do
    Kernel.should have_private_instance_method(:proc)
  end

  it "creates a proc-style Proc if given a literal block" do
    l = proc { 42 }
    l.lambda?.should be_false
  end

  it "returned the passed Proc if given an existing Proc" do
    some_lambda = -> {}
    some_lambda.lambda?.should be_true
    l = proc(&some_lambda)
    l.should equal(some_lambda)
    l.lambda?.should be_true
  end

  it_behaves_like :kernel_lambda, :proc

  it "returns from the creation site of the proc, not just the proc itself" do
    @reached_end_of_method = nil
    def test
      proc { return }.call
      @reached_end_of_method = true
    end
    test
    @reached_end_of_method.should be_nil
  end
end

describe "Kernel#proc" do
  def some_method
    proc
  end

  ruby_version_is ""..."2.7" do
    it "uses the implicit block from an enclosing method" do
      prc = some_method { "hello" }

      prc.call.should == "hello"
    end
  end

  ruby_version_is "2.7"..."2.8" do
    it "can be created when called with no block" do
      -> {
        some_method { "hello" }
      }.should complain(/Capturing the given block using Kernel#proc is deprecated/)
    end
  end

  ruby_version_is "2.8" do
    it "raises an ArgumentError when passed no block" do
      -> {
        some_method { "hello" }
      }.should raise_error(ArgumentError, 'tried to create Proc object without a block')
    end
  end
end