no easy way to set locals in view specs

[mreinsch]

What Ruby, Rails and RSpec versions are you using?

Ruby version: ruby 3.0.4p208 (2022-04-12 revision 3fa771dded) [x86_64-darwin21]
Rails version: Rails 7.0.4.3
RSpec version: RSpec 3.12

• rspec-core 3.12.2
• rspec-expectations 3.12.3
• rspec-mocks 3.12.5
• rspec-rails 6.0.2
• rspec-support 3.12.0

Observed behaviour

This is about a view spec. While writing a test for a partial which uses a local variable I couldn't find a documented way on how to approach it. I tried:

render {}, { variable_name: some_object }

but that resulted in local_assigns in the template to be an empty hash and thus the rendering failed.

Expected behaviour

Provide an easy way to pass local variables to a partial.

Investigation / Suggested fix

The render method (defined as https://github.com/rspec/rspec-rails/blob/main/lib/rspec/rails/example/view_example_group.rb#LL66C8-L66C61): render(options = {}, local_assigns = {}, &block) only seems to pass local_assigns through in case options is not as Hash (i.e. a String). Otherwise the code will refer to options[:locals].

Thus I'd suggest the following code for the render method to allow passing locals:

def render(options = {}, local_assigns = {}, &block)
  options = _default_render_options.merge(options) if options.is_a?(Hash) && !(options[:partial] || options[:template])
  super(options, local_assigns, &block)
end

Then it's possible to use

render locals: { variable_name: some_object }

which looks nicer.

If that's acceptable, I can prepare a PR.

[JonRowe]

Apologies for the delay in looking into this, there are two ways we support for rendering partials with locals, see:
https://rspec.info/features/6-0/rspec-rails/view-specs/view-spec/

First, explicit partials:

render :partial => "widgets/widget", :locals => {:widget => widget}

Second, implicit partials:

render "widgets/widget", :widget => widget

[JonRowe]

Theres actually a whole bunch of keys you can pass to Rails to render here, and you actually have to provide something, so but we can use the defaults which check the implicit template, and merge in the locals, which is what I've done in #2686

[JonRowe]

#2686 will allow render locals: { ... } by defaulting to the template behaviour.