From c740ebdaf580c8c9772a9099c7a9c11ef3105f3a Mon Sep 17 00:00:00 2001
From: Aaron Patterson <aaron.patterson@gmail.com>
Date: Wed, 16 Jan 2019 17:28:03 -0800
Subject: [PATCH] Always evaluate views against an ActionView::Base

Methods created by views should always be evaluated against an AV::Base
instance.  This way we can extract and refactor things in to classes.
---
 actionview/lib/action_view/base.rb                     |  7 +++++++
 actionview/lib/action_view/template.rb                 |  6 +++---
 .../lib/action_view/template/handlers/erb/erubi.rb     | 10 ++++++----
 actionview/test/abstract_unit.rb                       |  2 +-
 actionview/test/template/template_test.rb              |  2 +-
 5 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/actionview/lib/action_view/base.rb b/actionview/lib/action_view/base.rb
index d41fe2a608..4318791760 100644
--- a/actionview/lib/action_view/base.rb
+++ b/actionview/lib/action_view/base.rb
@@ -210,6 +210,13 @@ module ActionView #:nodoc:
       _prepare_context
     end
 
+    def run(method, locals, buffer, &block)
+      _old_output_buffer = @output_buffer
+      send(method, locals, buffer, &block)
+    ensure
+      @output_buffer = _old_output_buffer
+    end
+
     ActiveSupport.run_load_hooks(:action_view, self)
   end
 end
diff --git a/actionview/lib/action_view/template.rb b/actionview/lib/action_view/template.rb
index da9f20990f..ed680df4c6 100644
--- a/actionview/lib/action_view/template.rb
+++ b/actionview/lib/action_view/template.rb
@@ -158,7 +158,7 @@ module ActionView
     def render(view, locals, buffer = ActionView::OutputBuffer.new, &block)
       instrument_render_template do
         compile!(view)
-        view.send(method_name, locals, buffer, &block)
+        view.run(method_name, locals, buffer, &block)
       end
     rescue => e
       handle_render_error(view, e)
@@ -301,9 +301,9 @@ module ActionView
         # encoding of the code
         source = +<<-end_src
           def #{method_name}(local_assigns, output_buffer)
-            _old_virtual_path, @virtual_path = @virtual_path, #{@virtual_path.inspect};_old_output_buffer = @output_buffer;#{locals_code};#{code}
+            _old_virtual_path, @virtual_path = @virtual_path, #{@virtual_path.inspect};#{locals_code};#{code}
           ensure
-            @virtual_path, @output_buffer = _old_virtual_path, _old_output_buffer
+            @virtual_path = _old_virtual_path
           end
         end_src
 
diff --git a/actionview/lib/action_view/template/handlers/erb/erubi.rb b/actionview/lib/action_view/template/handlers/erb/erubi.rb
index d379d7ec12..d0e87e6e7f 100644
--- a/actionview/lib/action_view/template/handlers/erb/erubi.rb
+++ b/actionview/lib/action_view/template/handlers/erb/erubi.rb
@@ -22,10 +22,12 @@ module ActionView
           end
 
           def evaluate(action_view_erb_handler_context)
-            pr = eval("proc { #{@src} }", binding, @filename || "(erubi)")
-            # Double assignment to eliminate -w warnings
-            output_buffer = output_buffer = ActionView::OutputBuffer.new
-            action_view_erb_handler_context.instance_eval(&pr)
+            src = @src
+            view = Class.new(ActionView::Base) {
+              include action_view_erb_handler_context._routes.url_helpers
+              class_eval("define_method(:_template) { |local_assigns, output_buffer| #{src} }", @filename || "(erubi)", 0)
+            }.new(action_view_erb_handler_context)
+            view.run(:_template, {}, ActionView::OutputBuffer.new)
           end
 
         private
diff --git a/actionview/test/abstract_unit.rb b/actionview/test/abstract_unit.rb
index f90626ad9e..d71944e938 100644
--- a/actionview/test/abstract_unit.rb
+++ b/actionview/test/abstract_unit.rb
@@ -61,7 +61,7 @@ module RenderERBUtils
       ActionView::Template::Handlers::ERB,
       {})
 
-    template.render(self, {}).strip
+    template.render(ActionView::Base.new, {}).strip
   end
 end
 
diff --git a/actionview/test/template/template_test.rb b/actionview/test/template/template_test.rb
index b348d1f17b..8257d97b7c 100644
--- a/actionview/test/template/template_test.rb
+++ b/actionview/test/template/template_test.rb
@@ -18,7 +18,7 @@ class TestERBTemplate < ActiveSupport::TestCase
     attr_accessor :formats
   end
 
-  class Context
+  class Context < ActionView::Base
     def initialize
       @output_buffer = "original"
       @virtual_path = nil