Add test coverage for Partial Helpers

[seanpdoyle]

Introduce renderer test coverage to exercise that Partials can declare their own isolated helper methods for use within templates.

[kaspth]

I don't understand why we can call upcase without doing partial.upcase?

[seanpdoyle]

Is this benefiting from a misuse of a Section definition?

https://github.com/bullet-train-co/nice_partials/blob/main/lib/nice_partials/partial.rb#L107

[kaspth]

Hm, I'm not quite sure what's going on here, I'll try to look locally.

[seanpdoyle]

@kaspth the outer |partial| block variable isn't available to inner block calls:

diff --git a/test/fixtures/_partial_with_helpers.html.erb b/test/fixtures/_partial_with_helpers.html.erb
index e4b57e3..3131172 100644
--- a/test/fixtures/_partial_with_helpers.html.erb
+++ b/test/fixtures/_partial_with_helpers.html.erb
@@ -11,3 +11,5 @@
 %>
 
 <p><%= upcase yield %></p>
+
+<%= partial.block %>
diff --git a/test/renderer_test.rb b/test/renderer_test.rb
index c5bcaf7..bde5a72 100644
--- a/test/renderer_test.rb
+++ b/test/renderer_test.rb
@@ -55,6 +55,14 @@ class RendererTest < NicePartials::Test
     assert_css "p", text: "TEXT WITH SPACES"
   end
 
+  test "render partial exposes helper methods within caller's blocks" do
+    render "partial_with_helpers" do |partial|
+      partial.block { partial.upcase("text in a block") }
+    end
+
+    assert_text "TEXT IN A BLOCK"
+  end
+
   test "accessing partial in outer context won't leak state to inner render" do
     render "partial_accessed_in_outer_context"

That makes the partial:

<%
  partial.helpers do
    def upcase(content)
      content.upcase
    end

    def squish(content)
      content.gsub(/\s+/, " ")
    end
  end
%>

<p><%= upcase yield %></p>

<%= partial.block %>

The test failure is something like:

Error:                                                                                                                                  
RendererTest#test_render_partial_exposes_helper_methods_within_caller's_blocks:                                                         
ActionView::Template::Error: undefined method `upcase' for nil:NilClass                                                                 
    test/renderer_test.rb:59:in `block in <class:RendererTest>'

[kaspth]

@kaspth the outer |partial| block variable isn't available to inner block calls:

interesting, I'm a little tired so I can't quite get it, do you want to double check now and open a new issue?