neovim/test/functional/ex_cmds/profile_spec.lua

require('os')
local lfs = require('lfs')

local helpers  = require('test.functional.helpers')(after_each)
local eval     = helpers.eval
local command  = helpers.command
local eq, neq  = helpers.eq, helpers.neq
local tempfile = helpers.tmpname()

-- tmpname() also creates the file on POSIX systems. Remove it again.
-- We just need the name, ignoring any race conditions.
if lfs.attributes(tempfile, 'uid') then
  os.remove(tempfile)
end

local function assert_file_exists(filepath)
  -- Use 2-argument lfs.attributes() so no extra table gets created.
  -- We don't really care for the uid.
  neq(nil, lfs.attributes(filepath, 'uid'))
end

local function assert_file_exists_not(filepath)
  eq(nil, lfs.attributes(filepath, 'uid'))
end

describe(':profile', function()
  before_each(helpers.clear)

  after_each(function()
    if lfs.attributes(tempfile, 'uid') ~= nil then
      os.remove(tempfile)
    end
  end)

  it('dump', function()
    eq(0, eval('v:profiling'))
    command('profile start ' .. tempfile)
    eq(1, eval('v:profiling'))
    assert_file_exists_not(tempfile)
    command('profile dump')
    assert_file_exists(tempfile)
  end)

  it('stop', function()
    command('profile start ' .. tempfile)
    assert_file_exists_not(tempfile)
    command('profile stop')
    assert_file_exists(tempfile)
    eq(0, eval('v:profiling'))
  end)
end)