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Zero monkey patching mode

Use the disable_monkey_patching! configuration option to disable all monkey patching done by RSpec:

  • stops exposing DSL globally
  • disables should and should_not syntax for rspec-expectations
  • disables stub, should_receive, and should_not_receive syntax for rspec-mocks
RSpec.configure { |c| c.disable_monkey_patching! }

Background​

Given a file named "spec/example_describe_spec.rb" with:

require 'spec_helper'

describe "specs here" do
  it "passes" do
  end
end

Given a file named "spec/example_should_spec.rb" with:

require 'spec_helper'

RSpec.describe "another specs here" do
  it "passes with monkey patched expectations" do
    x = 25
    x.should eq 25
    x.should_not be > 30
  end

  it "passes with monkey patched mocks" do
    x = double("thing")
    x.stub(:hello => [:world])
    x.should_receive(:count).and_return(4)
    x.should_not_receive(:all)
    (x.hello * x.count).should eq([:world, :world, :world, :world])
  end
end

Given a file named "spec/example_expect_spec.rb" with:

require 'spec_helper'

RSpec.describe "specs here too" do
  it "passes in zero monkey patching mode" do
    x = double("thing")
    allow(x).to receive(:hello).and_return([:world])
    expect(x).to receive(:count).and_return(4)
    expect(x).not_to receive(:all)
    expect(x.hello * x.count).to eq([:world, :world, :world, :world])
  end

  it "passes in zero monkey patching mode" do
    x = 25
    expect(x).to eq(25)
    expect(x).not_to be > 30
  end
end

By default RSpec allows monkey patching​

Given a file named "spec/spec_helper.rb" with:

# Empty spec_helper

When I run rspec

Then the examples should all pass.

Monkey patched methods are undefined with disable_monkey_patching!​

Given a file named "spec/spec_helper.rb" with:

RSpec.configure do |config|
  config.disable_monkey_patching!
end

When I run rspec spec/example_should_spec.rb

Then the output should contain all of these:

| undefined method `should' | | unexpected message :stub |

When I run rspec spec/example_describe_spec.rb

Then the output should contain "undefined method `describe'".

allow and expect syntax works with monkey patching​

Given a file named "spec/spec_helper.rb" with:

# Empty spec_helper

When I run rspec spec/example_expect_spec.rb

Then the examples should all pass.

allow and expect syntax works without monkey patching​

Given a file named "spec/spec_helper.rb" with:

RSpec.configure do |config|
  config.disable_monkey_patching!
end

When I run rspec spec/example_expect_spec.rb

Then the examples should all pass.