Issue #9315: Fix for the trace module to record correct class name

when tracing methods.  Unit tests. Patch by Eli Bendersky.

Lib/test/test_trace.py

+import os
+import sys
+from test.test_support import (run_unittest, TESTFN, rmtree, unlink,
+                               captured_stdout)
+import unittest
+
+import trace
+from trace import CoverageResults, Trace
+
+from test.tracedmodules import testmod
+
+
+#------------------------------- Utilities -----------------------------------#
+
+def fix_ext_py(filename):
+    """Given a .pyc/.pyo filename converts it to the appropriate .py"""
+    if filename.endswith(('.pyc', '.pyo')):
+        filename = filename[:-1]
+    return filename
+
+def my_file_and_modname():
+    """The .py file and module name of this file (__file__)"""
+    modname = os.path.splitext(os.path.basename(__file__))[0]
+    return fix_ext_py(__file__), modname
+
+def get_firstlineno(func):
+    return func.__code__.co_firstlineno
+
+#-------------------- Target functions for tracing ---------------------------#
+#
+# The relative line numbers of lines in these functions matter for verifying
+# tracing. Please modify the appropriate tests if you change one of the
+# functions. Absolute line numbers don't matter.
+#
+
+def traced_func_linear(x, y):
+    a = x
+    b = y
+    c = a + b
+    return c
+
+def traced_func_loop(x, y):
+    c = x
+    for i in range(5):
+        c += y
+    return c
+
+def traced_func_importing(x, y):
+    return x + y + testmod.func(1)
+
+def traced_func_simple_caller(x):
+    c = traced_func_linear(x, x)
+    return c + x
+
+def traced_func_importing_caller(x):
+    k = traced_func_simple_caller(x)
+    k += traced_func_importing(k, x)
+    return k
+
+def traced_func_generator(num):
+    c = 5       # executed once
+    for i in range(num):
+        yield i + c
+
+def traced_func_calling_generator():
+    k = 0
+    for i in traced_func_generator(10):
+        k += i
+
+def traced_doubler(num):
+    return num * 2
+
+def traced_caller_list_comprehension():
+    k = 10
+    mylist = [traced_doubler(i) for i in range(k)]
+    return mylist
+
+
+class TracedClass(object):
+    def __init__(self, x):
+        self.a = x
+
+    def inst_method_linear(self, y):
+        return self.a + y
+
+    def inst_method_calling(self, x):
+        c = self.inst_method_linear(x)
+        return c + traced_func_linear(x, c)
+
+    @classmethod
+    def class_method_linear(cls, y):
+        return y * 2
+
+    @staticmethod
+    def static_method_linear(y):
+        return y * 2
+
+
+#------------------------------ Test cases -----------------------------------#
+
+
+class TestLineCounts(unittest.TestCase):
+    """White-box testing of line-counting, via runfunc"""
+    def setUp(self):
+        self.tracer = Trace(count=1, trace=0, countfuncs=0, countcallers=0)
+        self.my_py_filename = fix_ext_py(__file__)
+
+    def test_traced_func_linear(self):
+        result = self.tracer.runfunc(traced_func_linear, 2, 5)
+        self.assertEqual(result, 7)
+
+        # all lines are executed once
+        expected = {}
+        firstlineno = get_firstlineno(traced_func_linear)
+        for i in range(1, 5):
+            expected[(self.my_py_filename, firstlineno +  i)] = 1
+
+        self.assertEqual(self.tracer.results().counts, expected)
+
+    def test_traced_func_loop(self):
+        self.tracer.runfunc(traced_func_loop, 2, 3)
+
+        firstlineno = get_firstlineno(traced_func_loop)
+        expected = {
+            (self.my_py_filename, firstlineno + 1): 1,
+            (self.my_py_filename, firstlineno + 2): 6,
+            (self.my_py_filename, firstlineno + 3): 5,
+            (self.my_py_filename, firstlineno + 4): 1,
+        }
+        self.assertEqual(self.tracer.results().counts, expected)
+
+    def test_traced_func_importing(self):
+        self.tracer.runfunc(traced_func_importing, 2, 5)
+
+        firstlineno = get_firstlineno(traced_func_importing)
+        expected = {
+            (self.my_py_filename, firstlineno + 1): 1,
+            (fix_ext_py(testmod.__file__), 2): 1,
+            (fix_ext_py(testmod.__file__), 3): 1,
+        }
+
+        self.assertEqual(self.tracer.results().counts, expected)
+
+    def test_trace_func_generator(self):
+        self.tracer.runfunc(traced_func_calling_generator)
+
+        firstlineno_calling = get_firstlineno(traced_func_calling_generator)
+        firstlineno_gen = get_firstlineno(traced_func_generator)
+        expected = {
+            (self.my_py_filename, firstlineno_calling + 1): 1,
+            (self.my_py_filename, firstlineno_calling + 2): 11,
+            (self.my_py_filename, firstlineno_calling + 3): 10,
+            (self.my_py_filename, firstlineno_gen + 1): 1,
+            (self.my_py_filename, firstlineno_gen + 2): 11,
+            (self.my_py_filename, firstlineno_gen + 3): 10,
+        }
+        self.assertEqual(self.tracer.results().counts, expected)
+
+    def test_trace_list_comprehension(self):
+        self.tracer.runfunc(traced_caller_list_comprehension)
+
+        firstlineno_calling = get_firstlineno(traced_caller_list_comprehension)
+        firstlineno_called = get_firstlineno(traced_doubler)
+        expected = {
+            (self.my_py_filename, firstlineno_calling + 1): 1,
+            (self.my_py_filename, firstlineno_calling + 2): 11,
+            (self.my_py_filename, firstlineno_calling + 3): 1,
+            (self.my_py_filename, firstlineno_called + 1): 10,
+        }
+        self.assertEqual(self.tracer.results().counts, expected)
+
+
+    def test_linear_methods(self):
+        # XXX todo: later add 'static_method_linear' and 'class_method_linear'
+        # here, once issue1764286 is resolved
+        #
+        for methname in ['inst_method_linear',]:
+            tracer = Trace(count=1, trace=0, countfuncs=0, countcallers=0)
+            traced_obj = TracedClass(25)
+            method = getattr(traced_obj, methname)
+            tracer.runfunc(method, 20)
+
+            firstlineno = get_firstlineno(method)
+            expected = {
+                (self.my_py_filename, firstlineno + 1): 1,
+            }
+            self.assertEqual(tracer.results().counts, expected)
+
+
+class TestRunExecCounts(unittest.TestCase):
+    """A simple sanity test of line-counting, via runctx (exec)"""
+    def setUp(self):
+        self.my_py_filename = fix_ext_py(__file__)
+
+    def test_exec_counts(self):
+        self.tracer = Trace(count=1, trace=0, countfuncs=0, countcallers=0)
+        code = r'''traced_func_loop(2, 5)'''
+        code = compile(code, __file__, 'exec')
+        self.tracer.runctx(code, globals(), vars())
+
+        firstlineno = get_firstlineno(traced_func_loop)
+        expected = {
+            (self.my_py_filename, firstlineno + 1): 1,
+            (self.my_py_filename, firstlineno + 2): 6,
+            (self.my_py_filename, firstlineno + 3): 5,
+            (self.my_py_filename, 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.tracer.results().counts[k], expected[k])
+
+
+class TestFuncs(unittest.TestCase):
+    """White-box testing of funcs tracing"""
+    def setUp(self):
+        self.tracer = Trace(count=0, trace=0, countfuncs=1)
+        self.filemod = my_file_and_modname()
+        self.maxDiff = None
+    def test_simple_caller(self):
+        self.tracer.runfunc(traced_func_simple_caller, 1)
+
+        expected = {
+            self.filemod + ('traced_func_simple_caller',): 1,
+            self.filemod + ('traced_func_linear',): 1,
+        }
+        self.assertEqual(self.tracer.results().calledfuncs, expected)
+
+    def test_loop_caller_importing(self):
+        self.tracer.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,
+            (fix_ext_py(testmod.__file__), 'testmod', 'func'): 1,
+        }
+        self.assertEqual(self.tracer.results().calledfuncs, expected)
+
+    def test_inst_method_calling(self):
+        obj = TracedClass(20)
+        self.tracer.runfunc(obj.inst_method_calling, 1)
+
+        expected = {
+            self.filemod + ('TracedClass.inst_method_calling',): 1,
+            self.filemod + ('TracedClass.inst_method_linear',): 1,
+            self.filemod + ('traced_func_linear',): 1,
+        }
+        self.assertEqual(self.tracer.results().calledfuncs, expected)
+
+
+class TestCallers(unittest.TestCase):
+    """White-box testing of callers tracing"""
+    def setUp(self):
+        self.tracer = Trace(count=0, trace=0, countcallers=1)
+        self.filemod = my_file_and_modname()
+
+    def test_loop_caller_importing(self):
+        self.tracer.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',)),
+                (fix_ext_py(testmod.__file__), 'testmod', 'func')): 1,
+        }
+        self.assertEqual(self.tracer.results().callers, expected)
+
+
+# Created separately for issue #3821
+class TestCoverage(unittest.TestCase):
+    def tearDown(self):
+        rmtree(TESTFN)
+        unlink(TESTFN)
+
+    def _coverage(self, tracer):
+        tracer.run('from test import test_pprint; test_pprint.test_main()')
+        r = tracer.results()
+        r.write_results(show_missing=True, summary=True, coverdir=TESTFN)
+
+    def test_coverage(self):
+        tracer = trace.Trace(trace=0, count=1)
+        with captured_stdout() as stdout:
+            self._coverage(tracer)
+        stdout = stdout.getvalue()
+        self.assertTrue("pprint.py" in stdout)
+        self.assertTrue("case.py" in stdout)   # from unittest
+        files = os.listdir(TESTFN)
+        self.assertTrue("pprint.cover" in files)
+        self.assertTrue("unittest.case.cover" in files)
+
+    def test_coverage_ignore(self):
+        # Ignore all files, nothing should be traced nor printed
+        libpath = os.path.normpath(os.path.dirname(os.__file__))
+        # sys.prefix does not work when running from a checkout
+        tracer = trace.Trace(ignoredirs=[sys.prefix, sys.exec_prefix, libpath],
+                             trace=0, count=1)
+        with captured_stdout() as stdout:
+            self._coverage(tracer)
+        if os.path.exists(TESTFN):
+            files = os.listdir(TESTFN)
+            self.assertEquals(files, [])
+
+
+def test_main():
+    run_unittest(__name__)
+
+
+if __name__ == '__main__':
+    test_main()

Lib/test/tracedmodules/__init__.py

+"""This package contains modules that help testing the trace.py module. Note
+that the exact location of functions in these modules is important, as trace.py
+takes the real line numbers into account.
+"""

Lib/test/tracedmodules/testmod.py

+def func(x):
+    b = x + 1
+    return b + 2

Lib/trace.py

@@ -56,7 +56,7 @@ import threading
 import time
 import token
 import tokenize
-import types
+import inspect
 import gc
 
 try:
@@ -398,7 +398,7 @@ def find_lines(code, strs):
 
     # and check the constants for references to other code objects
     for c in code.co_consts:
-        if isinstance(c, types.CodeType):
+        if inspect.iscode(c):
             # find another code object, so recurse into it
             linenos.update(find_lines(c, strs))
     return linenos
@@ -545,7 +545,7 @@ class Trace:
             ## use of gc.get_referrers() was suggested by Michael Hudson
             # all functions which refer to this code object
             funcs = [f for f in gc.get_referrers(code)
-                         if hasattr(f, "func_doc")]
+                         if inspect.isfunction(f)]
             # require len(func) == 1 to avoid ambiguity caused by calls to
             # new.function(): "In the face of ambiguity, refuse the
             # temptation to guess."
@@ -557,17 +557,13 @@ class Trace:
                                    if hasattr(c, "__bases__")]
                     if len(classes) == 1:
                         # ditto for new.classobj()
-                        clsname = str(classes[0])
+                        clsname = classes[0].__name__
                         # cache the result - assumption is that new.* is
                         # not called later to disturb this relationship
                         # _caller_cache could be flushed if functions in
                         # the new module get called.
                         self._caller_cache[code] = clsname
         if clsname is not None:
-            # final hack - module name shows up in str(cls), but we've already
-            # computed module name, so remove it
-            clsname = clsname.split(".")[1:]
-            clsname = ".".join(clsname)
             funcname = "%s.%s" % (clsname, funcname)
 
         return filename, modulename, funcname

Misc/NEWS

@@ -255,6 +255,9 @@ Library
 
 - Issue #9164: Ensure sysconfig handles dupblice archs while building on OSX
 
+- Issue #9315: Fix for the trace module to record correct class name
+  for tracing methods.
+
 Extension Modules
 -----------------
 
@@ -337,6 +340,8 @@ Build
 Tests
 -----
 
+- Issue #9315: Added tests for the trace module.  Patch by Eli Bendersky.
+ 
 - Strengthen test_unicode with explicit type checking for assertEqual tests.
 
 - Issue #8857: Provide a test case for socket.getaddrinfo.