diff --git a/scripts/benchmark.lua b/scripts/benchmark.lua
index 457b671..56c3377 100644
--- a/scripts/benchmark.lua
+++ b/scripts/benchmark.lua
@@ -1,48 +1,64 @@
 package.path = "lua/?.lua;" .. package.path
 local libivy = require "ivy.libivy"
+local vim_mock = require "ivy.vim_mock"
+local window = require "ivy.window"
 
 local benchmark = function(name, n, callback)
   local status = {
     running_total = 0,
     min = 999999999999999999,
     max = -0000000000000000,
   }
 
   for _ = 1, n do
     local start_time = os.clock()
     callback()
     local running_time = os.clock() - start_time
 
     status.running_total = status.running_total + running_time
     if status.min > running_time then
       status.min = running_time
     end
 
     if status.max < running_time then
       status.max = running_time
     end
   end
 
   print(
     string.format(
-      "| %-30s | %09.6f (s) | %09.6f (s) | %09.6f (s) | %09.6f (s) |",
+      "| %-41s | %09.6f (s) | %09.6f (s) | %09.6f (s) | %09.6f (s) |",
       name,
       status.running_total,
       status.running_total / n,
       status.min,
       status.max
     )
   )
 end
 
-print "| Name                           | Total         | Average       | Min           | Max           |"
-print "|--------------------------------|---------------|---------------|---------------|---------------|"
+print "| Name                                      | Total         | Average       | Min           | Max           |"
+print "|-------------------------------------------|---------------|---------------|---------------|---------------|"
 
 benchmark("ivy_match(file.lua) 1000000x", 1000000, function()
   libivy.ivy_match("file.lua", "some/long/path/to/file/file.lua")
 end)
 
 libivy.ivy_init "/tmp/ivy-trees/kubernetes"
 benchmark("ivy_files(kubernetes) 100x", 100, function()
   libivy.ivy_files("file.go", "/tmp/ivy-trees/kubernetes")
 end)
+
+-- Mock the vim API so we can run `vim.` functions. Override the
+-- `nvim_buf_set_lines` function, this is so very slow. It saves all of the
+-- lines so we can assert on them in the tests. For benchmarking we don't need
+-- any of this, we can't control the vim internals.
+vim_mock.reset()
+_G.vim.api.nvim_buf_set_lines = function() end
+
+window.initialize()
+
+benchmark("ivy_files_with_set_items(kubernetes) 100x", 100, function()
+  local items = libivy.ivy_files(".go", "/tmp/ivy-trees/kubernetes")
+  window.set_items(items)
+end)