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

require_relative '../../spec_helper'
require_relative 'fixtures/classes'

describe "Kernel.binding" do
  it "returns a binding for the caller" do
    Kernel.binding.eval("self").should == self
  end
end

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

  before :each do
    @b1 = KernelSpecs::Binding.new(99).get_binding
    ScratchPad.clear
  end

  it "returns a Binding object" do
    @b1.kind_of?(Binding).should == true
  end

  it "encapsulates the execution context properly" do
    eval("@secret", @b1).should == 100
    eval("a", @b1).should == true
    eval("b", @b1).should == true
    eval("@@super_secret", @b1).should == "password"

    eval("square(2)", @b1).should == 4
    eval("self.square(2)", @b1).should == 4

    eval("a = false", @b1)
    eval("a", @b1).should == false
  end

  it "raises a NameError on undefined variable" do
    -> { eval("a_fake_variable", @b1) }.should raise_error(NameError)
  end

  it "uses the closure's self as self in the binding" do
    m = mock(:whatever)
    eval('self', m.send(:binding)).should == self
  end

  it "uses the class as self in a Class.new block" do
    m = mock(:whatever)
    cls = Class.new { ScratchPad.record eval('self', m.send(:binding)) }
    ScratchPad.recorded.should == cls
  end
end