From 6478677ec20c34ef858ed9d6004aac3b06c54d5a Mon Sep 17 00:00:00 2001
From: Jack Rothrock <jack@scoutapm.com>
Date: Wed, 24 Jan 2024 12:14:37 -0700
Subject: [PATCH] Add tests

---
 scout_apm.gemspec                             |  3 +
 test/test_helper.rb                           |  6 ++
 test/unit/instruments/action_view_test.rb     | 85 +++++++++++++++++++
 .../instruments/fixtures/simple_view.html.erb |  9 ++
 .../fixtures/test/_simple_partial.html.erb    |  3 +
 5 files changed, 106 insertions(+)
 create mode 100644 test/unit/instruments/action_view_test.rb
 create mode 100644 test/unit/instruments/fixtures/simple_view.html.erb
 create mode 100644 test/unit/instruments/fixtures/test/_simple_partial.html.erb

diff --git a/scout_apm.gemspec b/scout_apm.gemspec
index b33a6baa..33774663 100644
--- a/scout_apm.gemspec
+++ b/scout_apm.gemspec
@@ -34,6 +34,9 @@ Gem::Specification.new do |s|
   # tests. Specific versions are pulled in using specific gemfiles, e.g. 
   # `gems/rails3.gemfile`.
   s.add_development_dependency "activerecord"
+  s.add_development_dependency "actionpack"
+  s.add_development_dependency "actionview"
+  s.add_development_dependency "nokogiri", "~> 1.12.0"
   s.add_development_dependency "sqlite3"
 
   s.add_development_dependency "rubocop"
diff --git a/test/test_helper.rb b/test/test_helper.rb
index dca6abc3..49e69370 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -65,7 +65,13 @@ def method_missing(sym)
   end
 end
 
+def remove_rails_namespace
+  Object.send(:remove_const, "Rails") if defined?(Rails)
+end
+
 def fake_rails(version)
+  remove_rails_namespace
+
   Kernel.const_set("Rails", Module.new)
   Kernel.const_set("ActionController", Module.new)
   r = Kernel.const_get("Rails")
diff --git a/test/unit/instruments/action_view_test.rb b/test/unit/instruments/action_view_test.rb
new file mode 100644
index 00000000..370d4b5c
--- /dev/null
+++ b/test/unit/instruments/action_view_test.rb
@@ -0,0 +1,85 @@
+require 'test_helper'
+require 'action_view'
+require 'action_pack'
+require 'action_controller'
+
+FIXTURE_LOAD_PATH = File.expand_path("fixtures", __dir__)
+
+include ActionView::Context
+
+module ActionController
+
+  class Base
+    self.view_paths = FIXTURE_LOAD_PATH
+
+    def self.test_routes(&block)
+      routes = ActionDispatch::Routing::RouteSet.new
+      routes.draw(&block)
+      include routes.url_helpers
+      routes
+    end
+  end
+
+  class TestCase
+    include ActionDispatch::TestProcess
+
+    def self.with_routes(&block)
+      routes = ActionDispatch::Routing::RouteSet.new
+      routes.draw(&block)
+      include Module.new {
+        define_method(:setup) do
+          super()
+          @routes = routes
+          @controller.singleton_class.include @routes.url_helpers if @controller
+        end
+      }
+      routes
+    end
+  end
+end
+
+class TestController < ActionController::Base
+
+  def render_simple_view
+    render template: "simple_view"
+  end
+end
+
+class RenderTest < ActionController::TestCase
+
+  tests TestController
+
+  with_routes do
+    get :render_simple_view, to: "test#render_simple_view"
+  end
+
+  def setup
+    # enable a logger so that (e.g.) the benchmarking stuff runs, so we can get
+    # a more accurate simulation of what happens in "real life".
+    super
+    @request.host = "www.scoutapm.com"
+
+    @old_view_paths = ActionController::Base.view_paths
+    ActionController::Base.view_paths = FIXTURE_LOAD_PATH
+  end
+
+  def teardown
+    ActionView::Base.logger = nil
+
+    ActionController::Base.view_paths = @old_view_paths
+  end
+
+  def test_partial_instrumentation
+    recorder = FakeRecorder.new
+    agent_context.recorder = recorder
+
+    instrument = ScoutApm::Instruments::ActionView.new(agent_context)
+    instrument.install(prepend: true)
+
+    get :render_simple_view
+    assert_response :success
+
+    assert_equal "simple_view/Rendering", recorder.requests.first.root_layer.name
+    assert_equal "test/_simple_partial/Rendering", recorder.requests.first.root_layer.children.first.name
+  end
+end
diff --git a/test/unit/instruments/fixtures/simple_view.html.erb b/test/unit/instruments/fixtures/simple_view.html.erb
new file mode 100644
index 00000000..0baa1f2a
--- /dev/null
+++ b/test/unit/instruments/fixtures/simple_view.html.erb
@@ -0,0 +1,9 @@
+<html>
+<head>
+  <title>Simple View</title>
+</head>
+<body>
+  <h1>Simple View</h1>
+  <%= render partial: "simple_partial", locals: { message: 'Simple Partial' } %>
+</body>
+</html>
\ No newline at end of file
diff --git a/test/unit/instruments/fixtures/test/_simple_partial.html.erb b/test/unit/instruments/fixtures/test/_simple_partial.html.erb
new file mode 100644
index 00000000..8c6b0abf
--- /dev/null
+++ b/test/unit/instruments/fixtures/test/_simple_partial.html.erb
@@ -0,0 +1,3 @@
+<div>
+  <p><%= @message %></p>
+</div>