Hack: check return values in ResolverDecorator

The alternative is to implement both `find_all` and `find_all_anywhere`. The
latter is only present since Rails 4.2.5.1, and the former has different arity
in different Rails versions. So either we have a version check, or we just check
the types of whatever is returned from the methods called in ResolverDecorator.

Author: bquorning

lib/rspec/rails/view_rendering.rb

@@ -61,8 +61,9 @@ def self.nullify_template_rendering(templates)
           end
         end
 
-        # Delegates find_templates to the submitted resolver and then returns templates
-        # with modified source
+        # Delegates all methods to the submitted resolver and for all methods
+        # that return a collection of `ActionView::Template` instances, return
+        # templates with modified source
         #
         # @private
         class ResolverDecorator
@@ -71,17 +72,17 @@ def initialize(resolver)
           end
 
           def method_missing(name, *args, &block)
-            @resolver.send(name, *args, &block)
+            result = @resolver.send(name, *args, &block)
+            nullify_templates(result)
           end
 
-          def find_all(name, prefix = nil, partial = false, details = {}, _key = nil, _locals = []) # rubocop:disable Style/ParameterLists
-            templates = find_templates(name, prefix, partial, details)
-            EmptyTemplateResolver.nullify_template_rendering(templates)
-          end
+        private
 
-          def find_all_anywhere(name, prefix, partial = false, details = {}, _key = nil, _locals = []) # rubocop:disable Style/ParameterLists
-            templates = find_templates(name, prefix, partial, details, true)
-            EmptyTemplateResolver.nullify_template_rendering(templates)
+          def nullify_templates(collection)
+            return collection unless collection.is_a?(Enumerable)
+            return collection unless collection.all? { |element| element.is_a?(::ActionView::Template) }
+
+            EmptyTemplateResolver.nullify_template_rendering(collection)
           end
         end
 
@@ -90,12 +91,9 @@ def find_all_anywhere(name, prefix, partial = false, details = {}, _key = nil, _
         #
         # @private
         class FileSystemResolver < ::ActionView::FileSystemResolver
-          def find_all(name, prefix = nil, partial = false, details = {}, _key = nil, _locals = []) # rubocop:disable Style/ParameterLists
-            templates = super
-            EmptyTemplateResolver.nullify_template_rendering(templates)
-          end
+        private
 
-          def find_all_anywhere(name, prefix, partial = false, details = {}, _key = nil, _locals = []) # rubocop:disable Style/ParameterLists
+          def find_templates(*args)
             templates = super
             EmptyTemplateResolver.nullify_template_rendering(templates)
           end