new_contents: import os
  import unittest
  
  from stacklogger import srcfile
  
  class TestUtils(unittest.TestCase):
      
      def test_srcfile(self):
          result = os.path.join(os.getcwd(), "foo.py")
          self.assertEquals(srcfile("foo.py"), result)
          self.assertEquals(srcfile("foo.pyc"), result)
          self.assertEquals(srcfile("foo.pyo"), result)
          self.assertEquals(srcfile("foo"), result[:-3])
  
subject: Add early tests.