cpython/Lib/test/test_lltrace.py

112 lines
3.7 KiB
Python

import dis
import textwrap
import unittest
from test import support
from test.support import os_helper
from test.support.script_helper import assert_python_ok
def example():
x = []
for i in range(0):
x.append(i)
x = "this is"
y = "an example"
print(x, y)
@unittest.skipUnless(support.Py_DEBUG, "lltrace requires Py_DEBUG")
class TestLLTrace(unittest.TestCase):
def run_code(self, code):
code = textwrap.dedent(code).strip()
with open(os_helper.TESTFN, 'w', encoding='utf-8') as fd:
self.addCleanup(os_helper.unlink, os_helper.TESTFN)
fd.write(code)
status, stdout, stderr = assert_python_ok(os_helper.TESTFN)
self.assertEqual(stderr, b"")
self.assertEqual(status, 0)
result = stdout.decode('utf-8')
if support.verbose:
print("\n\n--- code ---")
print(code)
print("\n--- stdout ---")
print(result)
print()
return result
def test_lltrace(self):
stdout = self.run_code("""
def dont_trace_1():
a = "a"
a = 10 * a
def trace_me():
for i in range(3):
+i
def dont_trace_2():
x = 42
y = -x
dont_trace_1()
__lltrace__ = 1
trace_me()
del __lltrace__
dont_trace_2()
""")
self.assertIn("GET_ITER", stdout)
self.assertIn("FOR_ITER", stdout)
self.assertIn("CALL_INTRINSIC_1", stdout)
self.assertIn("POP_TOP", stdout)
self.assertNotIn("BINARY_OP", stdout)
self.assertNotIn("UNARY_NEGATIVE", stdout)
self.assertIn("'trace_me' in module '__main__'", stdout)
self.assertNotIn("dont_trace_1", stdout)
self.assertNotIn("'dont_trace_2' in module", stdout)
def test_lltrace_different_module(self):
stdout = self.run_code("""
from test import test_lltrace
test_lltrace.__lltrace__ = 1
test_lltrace.example()
""")
self.assertIn("'example' in module 'test.test_lltrace'", stdout)
self.assertIn('LOAD_CONST', stdout)
self.assertIn('FOR_ITER', stdout)
self.assertIn('this is an example', stdout)
# check that offsets match the output of dis.dis()
instr_map = {i.offset: i for i in dis.get_instructions(example, adaptive=True)}
for line in stdout.splitlines():
offset, colon, opname_oparg = line.partition(":")
if not colon:
continue
offset = int(offset)
opname_oparg = opname_oparg.split()
if len(opname_oparg) == 2:
opname, oparg = opname_oparg
oparg = int(oparg)
else:
(opname,) = opname_oparg
oparg = None
self.assertEqual(instr_map[offset].opname, opname)
self.assertEqual(instr_map[offset].arg, oparg)
def test_lltrace_does_not_crash_on_subscript_operator(self):
# If this test fails, it will reproduce a crash reported as
# bpo-34113. The crash happened at the command line console of
# debug Python builds with __lltrace__ enabled (only possible in console),
# when the internal Python stack was negatively adjusted
stdout = self.run_code("""
import code
console = code.InteractiveConsole()
console.push('__lltrace__ = 1')
console.push('a = [1, 2, 3]')
console.push('a[0] = 1')
print('unreachable if bug exists')
""")
self.assertIn("unreachable if bug exists", stdout)
if __name__ == "__main__":
unittest.main()