From 537481ea60697ec1a615290fba67a4d0ecc8293c Mon Sep 17 00:00:00 2001
From: Stephen Nelson <stephen@katalyst.com.au>
Date: Wed, 27 Mar 2024 16:38:05 +1030
Subject: [PATCH] Prepend controller path to lookup_context prefixes

Rails rendering assumes that the first prefix encountered is 'special', specifically, it's the controller's prefix. This can be seen in `ActionView::AbstractRenderer::ObjectRendering#initialize`. This change injects the controller path at the start of the prefix list instead of the end to make sure this assumption is satisfied.

Resolves #2729.
---
 lib/rspec/rails/example/view_example_group.rb |  2 +-
 .../rails/example/view_example_group_spec.rb  | 20 +++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/lib/rspec/rails/example/view_example_group.rb b/lib/rspec/rails/example/view_example_group.rb
index a03b19958..dcd34a6ac 100644
--- a/lib/rspec/rails/example/view_example_group.rb
+++ b/lib/rspec/rails/example/view_example_group.rb
@@ -186,7 +186,7 @@ def _include_controller_helpers
 
         before do
           _include_controller_helpers
-          view.lookup_context.prefixes << _controller_path
+          view.lookup_context.prefixes.prepend(_controller_path)
 
           controller.controller_path = _controller_path
 
diff --git a/spec/rspec/rails/example/view_example_group_spec.rb b/spec/rspec/rails/example/view_example_group_spec.rb
index 7dd0b3fec..be8debcbb 100644
--- a/spec/rspec/rails/example/view_example_group_spec.rb
+++ b/spec/rspec/rails/example/view_example_group_spec.rb
@@ -255,6 +255,26 @@ def _view; end # Stub method
         expect(failure_reporter.exceptions).to eq []
         expect(run_count).to eq 1
       end
+
+      # Rails expects the first prefix to be the controller path.
+      # @see ActionView::AbstractRenderer::ObjectRendering#initialize
+      # Regression test for rspec/rspec-rails#2729
+      it 'injects controller path as first prefix' do
+        prefixes = []
+        RSpec.describe "a view spec" do
+          include ::RSpec::Rails::ViewExampleGroup
+
+          def _controller_path
+            "example/path"
+          end
+
+          specify do
+            prefixes = view.lookup_context.prefixes
+          end
+        end.run
+
+        expect(prefixes).to start_with("example/path")
+      end
     end
 
     describe "#template" do