move tmpdir handling into ProxyRunner

spec/support/app_runner.rb

@@ -17,7 +17,6 @@ class AppRunner
   def initialize(fixture, proxy = nil, env = {}, debug = false, delete = true)
     @run    = false
     @debug  = debug
-    @tmpdir = nil
     @proxy  = nil
     @delete = delete
     env.merge!("STATIC_DEBUG" => "true") if @debug
@@ -32,16 +31,7 @@ class AppRunner
     }
 
     if proxy
-      if proxy.is_a?(String)
-        @tmpdir = Dir.mktmpdir
-        File.open("#{@tmpdir}/config.ru", "w") do |file|
-          file.puts %q{require "sinatra"}
-          file.puts proxy
-          file.puts "run Sinatra::Application"
-        end
-      end
-
-      @proxy = ProxyRunner.new(@tmpdir, @delete)
+      @proxy = ProxyRunner.new(proxy, @delete)
       app_options["Links"] = ["#{@proxy.id}:proxy"]
       @proxy.start
 
@@ -107,8 +97,6 @@ class AppRunner
     end
     @router.destroy
     @app.delete(force: true) if @delete
-  ensure
-    FileUtils.rm_rf(@tmpdir) if @tmpdir
   end
 
   private

spec/support/proxy_runner.rb

+require "tmpdir"
 require_relative "proxy_builder"
 require_relative "container_runner"
 
 class ProxyRunner < ContainerRunner
   def initialize(config_ru = nil, delete = true)
+    @tmpdir = write_config_ru(config_ru)
+
     options = {
       "Image" => ProxyBuilder::TAG
     }
-    options["HostConfig"] = { "Binds" => ["#{config_ru}:/app/config/"] } if config_ru
+    options["HostConfig"] = { "Binds" => ["#{@tmpdir}:/app/config/"] } if @tmpdir
 
     super(options, delete)
   end
+
+  def destroy
+    super
+  ensure
+    FileUtils.rm_rf(@tmpdir) if @tmpdir
+  end
+
+  private
+  def write_config_ru(config_ru)
+    tmpdir = nil
+
+    if config_ru && config_ru.is_a?(String)
+      tmpdir = Dir.mktmpdir
+      File.open("#{tmpdir}/config.ru", "w") do |file|
+        file.puts %q{require "sinatra"}
+        file.puts config_ru
+        file.puts "run Sinatra::Application"
+      end
+    end
+
+    tmpdir
+  end
 end