diff --git a/Lib/test/test_trace.py b/Lib/test/test_trace.py
new file mode 100644
index 0000000..c04be50
--- /dev/null
+++ b/Lib/test/test_trace.py
@@ -0,0 +1,214 @@
+import imp
+import os
+import sys
+from test import test_support
+import unittest
+
+import trace
+from trace import CoverageResults, Trace
+
+
+#------------------------------- Utilities -----------------------------------#
+
+def make_fake_module():
+    """Creates a fake module named 'fakemodule'.
+
+    The new module has a single function named 'foo', and it's placed in
+    sys.modules
+    The file this fake module "comes from" is fakefile.py
+
+    """
+
+    # Prepare the function to import from the fake module
+    #
+    _fake_foo_src = r'''
+def foo(a_):
+    b = a_ + 1
+    return b + 2
+'''.lstrip()
+
+    _fake_foo = compile(_fake_foo_src, 'fakefile.py', 'exec')
+
+    # Create a new module, place the function into it and add it to sys.modules
+    #
+    fakemodule = imp.new_module('fakemodule')
+    exec _fake_foo in fakemodule.__dict__
+    fakemodule.__file__ = 'fakefile.py'
+    sys.modules['fakemodule'] = fakemodule
+
+
+def modname(filename):
+    """Infer a module name from a containing file name"""
+    base = os.path.basename(filename)
+    mod, ext = os.path.splitext(base)
+    return mod
+
+
+def my_file_and_modname():
+    """The file and module name of this file (__file__)"""
+    return __file__, modname(__file__)
+
+
+#-------------------- Target functions for tracing ---------------------------#
+
+def _traced_func_linear(a_, b_):
+    a = a_
+    b = b_
+    c = a + b
+    return c
+
+def _traced_func_loop(a_, b_):
+    c = a_
+    for i in range(5):
+        c += b_
+    return c
+
+# Expects the 'fakemodule' module to exist and have a 'foo' function in it
+#
+def _traced_func_importing(a_, b_):
+    from fakemodule import foo
+    return a_ + b_ + foo(1)
+
+def _traced_func_simple_caller(a_):
+    c = _traced_func_linear(a_, a_)
+    return c + a_
+
+def _traced_func_importing_caller(a_):
+    k = _traced_func_simple_caller(a_)
+    k += _traced_func_importing(k, a_)
+    return k
+
+
+#------------------------------ Test cases -----------------------------------#
+
+
+class TestLineCounts(unittest.TestCase):
+    """White-box testing of line-counting, via runfunc"""
+    def setUp(self):
+        self.tr = Trace(count=1, trace=0, countfuncs=0, countcallers=0)
+
+    def test_traced_func_linear(self):
+        result = self.tr.runfunc(_traced_func_linear, 2, 5)
+        self.assertEqual(result, 7)
+
+        # all lines are executed once
+        expected = {}
+        firstlineno = _traced_func_linear.__code__.co_firstlineno
+        for i in range(1, 5):
+            expected[(__file__, firstlineno +  i)] = 1
+
+        self.assertEqual(self.tr.results().counts, expected)
+
+    def test_traced_func_loop(self):
+        self.tr.runfunc(_traced_func_loop, 2, 3)
+
+        firstlineno = _traced_func_loop.__code__.co_firstlineno
+        expected = {
+            (__file__, firstlineno + 1): 1,
+            (__file__, firstlineno + 2): 6,
+            (__file__, firstlineno + 3): 5,
+            (__file__, firstlineno + 4): 1,
+        }
+        self.assertEqual(self.tr.results().counts, expected)
+
+    def test_traced_func_importing(self):
+        make_fake_module()
+        self.tr.runfunc(_traced_func_importing, 2, 5)
+
+        firstlineno = _traced_func_importing.__code__.co_firstlineno
+        expected = {
+            (__file__, firstlineno + 1): 1,
+            (__file__, firstlineno + 2): 1,
+            ('fakefile.py', 2): 1,
+            ('fakefile.py', 3): 1,
+        }
+        self.assertEqual(self.tr.results().counts, expected)
+
+
+class TestRunExecCounts(unittest.TestCase):
+    """A simple sanity test of line-counting, via run (exec)"""
+    def test_tt(self):
+        self.tr = Trace(count=1, trace=0, countfuncs=0, countcallers=0)
+        code = r'''_traced_func_loop(2, 5)'''
+        code = compile(code, __file__, 'exec')
+        self.tr.run(code)
+
+        firstlineno = _traced_func_loop.__code__.co_firstlineno
+        expected = {
+            (__file__, firstlineno + 1): 1,
+            (__file__, firstlineno + 2): 6,
+            (__file__, firstlineno + 3): 5,
+            (__file__, firstlineno + 4): 1,
+        }
+
+        # When used through 'run', some other spurios counts are produced, like
+        # the settrace of threading, which we ignore, just making sure that the
+        # counts fo _traced_func_loop were right.
+        #
+        for k in expected.keys():
+            self.assertEqual(self.tr.results().counts[k], expected[k])
+
+
+class TestFuncs(unittest.TestCase):
+    """White-box testing of funcs tracing"""
+    def setUp(self):
+        self.tr = Trace(count=0, trace=0, countfuncs=1)
+        self.filemod = my_file_and_modname()
+
+    def test_simple_caller(self):
+        self.tr.runfunc(_traced_func_simple_caller, 1)
+
+        expected = {
+            self.filemod + ('_traced_func_simple_caller',): 1,
+            self.filemod + ('_traced_func_linear',): 1,
+        }
+        self.assertEqual(self.tr.results().calledfuncs, expected)
+
+    def test_loop_caller_importing(self):
+        make_fake_module()
+        self.tr.runfunc(_traced_func_importing_caller, 1)
+
+        expected = {
+            self.filemod + ('_traced_func_simple_caller',): 1,
+            self.filemod + ('_traced_func_linear',): 1,
+            self.filemod + ('_traced_func_importing_caller',): 1,
+            self.filemod + ('_traced_func_importing',): 1,
+            ('fakefile.py', 'fakefile', 'foo'): 1,
+        }
+        self.assertEqual(self.tr.results().calledfuncs, expected)
+
+
+class TestCallers(unittest.TestCase):
+    """White-box testing of callers tracing"""
+    def setUp(self):
+        self.tr = Trace(count=0, trace=0, countcallers=1)
+        self.filemod = my_file_and_modname()
+
+    def test_loop_caller_importing(self):
+        make_fake_module()
+        self.tr.runfunc(_traced_func_importing_caller, 1)
+
+        expected = {
+            ((os.path.splitext(trace.__file__)[0] + '.py', 'trace', 'Trace.runfunc'),
+                (self.filemod + ('_traced_func_importing_caller',))): 1,
+            ((self.filemod + ('_traced_func_simple_caller',)),
+                (self.filemod + ('_traced_func_linear',))): 1,
+            ((self.filemod + ('_traced_func_importing_caller',)),
+                (self.filemod + ('_traced_func_simple_caller',))): 1,
+            ((self.filemod + ('_traced_func_importing_caller',)),
+                (self.filemod + ('_traced_func_importing',))): 1,
+            ((self.filemod + ('_traced_func_importing',)),
+                ('fakefile.py', 'fakefile', 'foo')): 1,
+        }
+        self.assertEqual(self.tr.results().callers, expected)
+
+
+#------------------------------ Driver ---------------------------------------#
+
+def test_main():
+    print(__name__, type(__name__))
+    test_support.run_unittest(__name__)
+
+
+if __name__ == '__main__':
+    test_main()