Make render_in_view_context forward its args to the block

[camertron]

What are you trying to accomplish?

Our render_in_view_context test helper uses instance_exec to evaluate the given block in the view context. Since instance_exec changes the value of self, instance variables, methods, etc defined in the caller's context are not available inside the block, which can be pretty confusing. For example, consider this test:

class MyTest < Minitest::Test
  def setup
    @user = create(:user)
  end

  def test_my_component
    render_in_view_context do
      render(MyComponent.new(@user))
    end
  end
end

As a direct result of using instance_exec, @user will be nil inside the block.

What approach did you choose and why?

Presumably to provide an escape hatch for this problem, instance_exec forwards its arguments when calling the block. This PR modifies render_in_view_context to forward its arguments to instance_exec, so this is now possible:

class MyTest < Minitest::Test
  def setup
    @user = create(:user)
  end

  def test_my_component
    render_in_view_context(@user) do |user|
      render(MyComponent.new(user))
    end
  end
end

[joelhawksley]

Makes sense to me. Mind adding a regression test?

[BlakeWilliams]

Nice, I really like this solution. 👍