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|
# Testing the line trace facility.
from test import support
import unittest
import sys
import difflib
import gc
from functools import wraps
import asyncio
class tracecontext:
"""Context manager that traces its enter and exit."""
def __init__(self, output, value):
self.output = output
self.value = value
def __enter__(self):
self.output.append(self.value)
def __exit__(self, *exc_info):
self.output.append(-self.value)
class asynctracecontext:
"""Asynchronous context manager that traces its aenter and aexit."""
def __init__(self, output, value):
self.output = output
self.value = value
async def __aenter__(self):
self.output.append(self.value)
async def __aexit__(self, *exc_info):
self.output.append(-self.value)
async def asynciter(iterable):
"""Convert an iterable to an asynchronous iterator."""
for x in iterable:
yield x
# A very basic example. If this fails, we're in deep trouble.
def basic():
return 1
basic.events = [(0, 'call'),
(1, 'line'),
(1, 'return')]
# Many of the tests below are tricky because they involve pass statements.
# If there is implicit control flow around a pass statement (in an except
# clause or else clause) under what conditions do you set a line number
# following that clause?
# Some constructs like "while 0:", "if 0:" or "if 1:...else:..." are optimized
# away. No code # exists for them, so the line numbers skip directly from
# "del x" to "x = 1".
def arigo_example0():
x = 1
del x
while 0:
pass
x = 1
arigo_example0.events = [(0, 'call'),
(1, 'line'),
(2, 'line'),
(5, 'line'),
(5, 'return')]
def arigo_example1():
x = 1
del x
if 0:
pass
x = 1
arigo_example1.events = [(0, 'call'),
(1, 'line'),
(2, 'line'),
(5, 'line'),
(5, 'return')]
def arigo_example2():
x = 1
del x
if 1:
x = 1
else:
pass
return None
arigo_example2.events = [(0, 'call'),
(1, 'line'),
(2, 'line'),
(4, 'line'),
(7, 'line'),
(7, 'return')]
# check that lines consisting of just one instruction get traced:
def one_instr_line():
x = 1
del x
x = 1
one_instr_line.events = [(0, 'call'),
(1, 'line'),
(2, 'line'),
(3, 'line'),
(3, 'return')]
def no_pop_tops(): # 0
x = 1 # 1
for a in range(2): # 2
if a: # 3
x = 1 # 4
else: # 5
x = 1 # 6
no_pop_tops.events = [(0, 'call'),
(1, 'line'),
(2, 'line'),
(3, 'line'),
(6, 'line'),
(2, 'line'),
(3, 'line'),
(4, 'line'),
(2, 'line'),
(2, 'return')]
def no_pop_blocks():
y = 1
while not y:
bla
x = 1
no_pop_blocks.events = [(0, 'call'),
(1, 'line'),
(2, 'line'),
(4, 'line'),
(4, 'return')]
def called(): # line -3
x = 1
def call(): # line 0
called()
call.events = [(0, 'call'),
(1, 'line'),
(-3, 'call'),
(-2, 'line'),
(-2, 'return'),
(1, 'return')]
def raises():
raise Exception
def test_raise():
try:
raises()
except Exception:
pass
test_raise.events = [(0, 'call'),
(1, 'line'),
(2, 'line'),
(-3, 'call'),
(-2, 'line'),
(-2, 'exception'),
(-2, 'return'),
(2, 'exception'),
(3, 'line'),
(4, 'line'),
(4, 'return')]
def _settrace_and_return(tracefunc):
sys.settrace(tracefunc)
sys._getframe().f_back.f_trace = tracefunc
def settrace_and_return(tracefunc):
_settrace_and_return(tracefunc)
settrace_and_return.events = [(1, 'return')]
def _settrace_and_raise(tracefunc):
sys.settrace(tracefunc)
sys._getframe().f_back.f_trace = tracefunc
raise RuntimeError
def settrace_and_raise(tracefunc):
try:
_settrace_and_raise(tracefunc)
except RuntimeError:
pass
settrace_and_raise.events = [(2, 'exception'),
(3, 'line'),
(4, 'line'),
(4, 'return')]
# implicit return example
# This test is interesting because of the else: pass
# part of the code. The code generate for the true
# part of the if contains a jump past the else branch.
# The compiler then generates an implicit "return None"
# Internally, the compiler visits the pass statement
# and stores its line number for use on the next instruction.
# The next instruction is the implicit return None.
def ireturn_example():
a = 5
b = 5
if a == b:
b = a+1
else:
pass
ireturn_example.events = [(0, 'call'),
(1, 'line'),
(2, 'line'),
(3, 'line'),
(4, 'line'),
(6, 'line'),
(6, 'return')]
# Tight loop with while(1) example (SF #765624)
def tightloop_example():
items = range(0, 3)
try:
i = 0
while 1:
b = items[i]; i+=1
except IndexError:
pass
tightloop_example.events = [(0, 'call'),
(1, 'line'),
(2, 'line'),
(3, 'line'),
(5, 'line'),
(5, 'line'),
(5, 'line'),
(5, 'line'),
(5, 'exception'),
(6, 'line'),
(7, 'line'),
(7, 'return')]
def tighterloop_example():
items = range(1, 4)
try:
i = 0
while 1: i = items[i]
except IndexError:
pass
tighterloop_example.events = [(0, 'call'),
(1, 'line'),
(2, 'line'),
(3, 'line'),
(4, 'line'),
(4, 'line'),
(4, 'line'),
(4, 'line'),
(4, 'exception'),
(5, 'line'),
(6, 'line'),
(6, 'return')]
def generator_function():
try:
yield True
"continued"
finally:
"finally"
def generator_example():
# any() will leave the generator before its end
x = any(generator_function())
# the following lines were not traced
for x in range(10):
y = x
generator_example.events = ([(0, 'call'),
(2, 'line'),
(-6, 'call'),
(-5, 'line'),
(-4, 'line'),
(-4, 'return'),
(-4, 'call'),
(-4, 'exception'),
(-1, 'line'),
(-1, 'return')] +
[(5, 'line'), (6, 'line')] * 10 +
[(5, 'line'), (5, 'return')])
class Tracer:
def __init__(self, trace_line_events=None, trace_opcode_events=None):
self.trace_line_events = trace_line_events
self.trace_opcode_events = trace_opcode_events
self.events = []
def _reconfigure_frame(self, frame):
if self.trace_line_events is not None:
frame.f_trace_lines = self.trace_line_events
if self.trace_opcode_events is not None:
frame.f_trace_opcodes = self.trace_opcode_events
def trace(self, frame, event, arg):
self._reconfigure_frame(frame)
self.events.append((frame.f_lineno, event))
return self.trace
def traceWithGenexp(self, frame, event, arg):
self._reconfigure_frame(frame)
(o for o in [1])
self.events.append((frame.f_lineno, event))
return self.trace
class TraceTestCase(unittest.TestCase):
# Disable gc collection when tracing, otherwise the
# deallocators may be traced as well.
def setUp(self):
self.using_gc = gc.isenabled()
gc.disable()
self.addCleanup(sys.settrace, sys.gettrace())
def tearDown(self):
if self.using_gc:
gc.enable()
@staticmethod
def make_tracer():
"""Helper to allow test subclasses to configure tracers differently"""
return Tracer()
def compare_events(self, line_offset, events, expected_events):
events = [(l - line_offset, e) for (l, e) in events]
if events != expected_events:
self.fail(
"events did not match expectation:\n" +
"\n".join(difflib.ndiff([str(x) for x in expected_events],
[str(x) for x in events])))
def run_and_compare(self, func, events):
tracer = self.make_tracer()
sys.settrace(tracer.trace)
func()
sys.settrace(None)
self.compare_events(func.__code__.co_firstlineno,
tracer.events, events)
def run_test(self, func):
self.run_and_compare(func, func.events)
def run_test2(self, func):
tracer = self.make_tracer()
func(tracer.trace)
sys.settrace(None)
self.compare_events(func.__code__.co_firstlineno,
tracer.events, func.events)
def test_set_and_retrieve_none(self):
sys.settrace(None)
assert sys.gettrace() is None
def test_set_and_retrieve_func(self):
def fn(*args):
pass
sys.settrace(fn)
try:
assert sys.gettrace() is fn
finally:
sys.settrace(None)
def test_01_basic(self):
self.run_test(basic)
def test_02_arigo0(self):
self.run_test(arigo_example0)
def test_02_arigo1(self):
self.run_test(arigo_example1)
def test_02_arigo2(self):
self.run_test(arigo_example2)
def test_03_one_instr(self):
self.run_test(one_instr_line)
def test_04_no_pop_blocks(self):
self.run_test(no_pop_blocks)
def test_05_no_pop_tops(self):
self.run_test(no_pop_tops)
def test_06_call(self):
self.run_test(call)
def test_07_raise(self):
self.run_test(test_raise)
def test_08_settrace_and_return(self):
self.run_test2(settrace_and_return)
def test_09_settrace_and_raise(self):
self.run_test2(settrace_and_raise)
def test_10_ireturn(self):
self.run_test(ireturn_example)
def test_11_tightloop(self):
self.run_test(tightloop_example)
def test_12_tighterloop(self):
self.run_test(tighterloop_example)
def test_13_genexp(self):
self.run_test(generator_example)
# issue1265: if the trace function contains a generator,
# and if the traced function contains another generator
# that is not completely exhausted, the trace stopped.
# Worse: the 'finally' clause was not invoked.
tracer = self.make_tracer()
sys.settrace(tracer.traceWithGenexp)
generator_example()
sys.settrace(None)
self.compare_events(generator_example.__code__.co_firstlineno,
tracer.events, generator_example.events)
def test_14_onliner_if(self):
def onliners():
if True: x=False
else: x=True
return 0
self.run_and_compare(
onliners,
[(0, 'call'),
(1, 'line'),
(3, 'line'),
(3, 'return')])
def test_15_loops(self):
# issue1750076: "while" expression is skipped by debugger
def for_example():
for x in range(2):
pass
self.run_and_compare(
for_example,
[(0, 'call'),
(1, 'line'),
(2, 'line'),
(1, 'line'),
(2, 'line'),
(1, 'line'),
(1, 'return')])
def while_example():
# While expression should be traced on every loop
x = 2
while x > 0:
x -= 1
self.run_and_compare(
while_example,
[(0, 'call'),
(2, 'line'),
(3, 'line'),
(4, 'line'),
(3, 'line'),
(4, 'line'),
(3, 'line'),
(3, 'return')])
def test_16_blank_lines(self):
namespace = {}
exec("def f():\n" + "\n" * 256 + " pass", namespace)
self.run_and_compare(
namespace["f"],
[(0, 'call'),
(257, 'line'),
(257, 'return')])
def test_17_none_f_trace(self):
# Issue 20041: fix TypeError when f_trace is set to None.
def func():
sys._getframe().f_trace = None
lineno = 2
self.run_and_compare(func,
[(0, 'call'),
(1, 'line')])
def test_18_except_with_name(self):
def func():
try:
try:
raise Exception
except Exception as e:
raise
x = "Something"
y = "Something"
except Exception:
pass
self.run_and_compare(func,
[(0, 'call'),
(1, 'line'),
(2, 'line'),
(3, 'line'),
(3, 'exception'),
(4, 'line'),
(5, 'line'),
(8, 'line'),
(9, 'line'),
(9, 'return')])
def test_19_except_with_finally(self):
def func():
try:
try:
raise Exception
finally:
y = "Something"
except Exception:
b = 23
self.run_and_compare(func,
[(0, 'call'),
(1, 'line'),
(2, 'line'),
(3, 'line'),
(3, 'exception'),
(5, 'line'),
(6, 'line'),
(7, 'line'),
(7, 'return')])
def test_20_async_for_loop(self):
class AsyncIteratorWrapper:
def __init__(self, obj):
self._it = iter(obj)
def __aiter__(self):
return self
async def __anext__(self):
try:
return next(self._it)
except StopIteration:
raise StopAsyncIteration
async def doit_async():
async for letter in AsyncIteratorWrapper("abc"):
x = letter
y = 42
def run(tracer):
x = doit_async()
try:
sys.settrace(tracer)
x.send(None)
finally:
sys.settrace(None)
tracer = self.make_tracer()
events = [
(0, 'call'),
(1, 'line'),
(-12, 'call'),
(-11, 'line'),
(-11, 'return'),
(-9, 'call'),
(-8, 'line'),
(-8, 'return'),
(-6, 'call'),
(-5, 'line'),
(-4, 'line'),
(-4, 'return'),
(1, 'exception'),
(2, 'line'),
(1, 'line'),
(-6, 'call'),
(-5, 'line'),
(-4, 'line'),
(-4, 'return'),
(1, 'exception'),
(2, 'line'),
(1, 'line'),
(-6, 'call'),
(-5, 'line'),
(-4, 'line'),
(-4, 'return'),
(1, 'exception'),
(2, 'line'),
(1, 'line'),
(-6, 'call'),
(-5, 'line'),
(-4, 'line'),
(-4, 'exception'),
(-3, 'line'),
(-2, 'line'),
(-2, 'exception'),
(-2, 'return'),
(1, 'exception'),
(3, 'line'),
(3, 'return')]
try:
run(tracer.trace)
except Exception:
pass
self.compare_events(doit_async.__code__.co_firstlineno,
tracer.events, events)
class SkipLineEventsTraceTestCase(TraceTestCase):
"""Repeat the trace tests, but with per-line events skipped"""
def compare_events(self, line_offset, events, expected_events):
skip_line_events = [e for e in expected_events if e[1] != 'line']
super().compare_events(line_offset, events, skip_line_events)
@staticmethod
def make_tracer():
return Tracer(trace_line_events=False)
@support.cpython_only
class TraceOpcodesTestCase(TraceTestCase):
"""Repeat the trace tests, but with per-opcodes events enabled"""
def compare_events(self, line_offset, events, expected_events):
skip_opcode_events = [e for e in events if e[1] != 'opcode']
if len(events) > 1:
self.assertLess(len(skip_opcode_events), len(events),
msg="No 'opcode' events received by the tracer")
super().compare_events(line_offset, skip_opcode_events, expected_events)
@staticmethod
def make_tracer():
return Tracer(trace_opcode_events=True)
class RaisingTraceFuncTestCase(unittest.TestCase):
def setUp(self):
self.addCleanup(sys.settrace, sys.gettrace())
def trace(self, frame, event, arg):
"""A trace function that raises an exception in response to a
specific trace event."""
if event == self.raiseOnEvent:
raise ValueError # just something that isn't RuntimeError
else:
return self.trace
def f(self):
"""The function to trace; raises an exception if that's the case
we're testing, so that the 'exception' trace event fires."""
if self.raiseOnEvent == 'exception':
x = 0
y = 1/x
else:
return 1
def run_test_for_event(self, event):
"""Tests that an exception raised in response to the given event is
handled OK."""
self.raiseOnEvent = event
try:
for i in range(sys.getrecursionlimit() + 1):
sys.settrace(self.trace)
try:
self.f()
except ValueError:
pass
else:
self.fail("exception not raised!")
except RuntimeError:
self.fail("recursion counter not reset")
# Test the handling of exceptions raised by each kind of trace event.
def test_call(self):
self.run_test_for_event('call')
def test_line(self):
self.run_test_for_event('line')
def test_return(self):
self.run_test_for_event('return')
def test_exception(self):
self.run_test_for_event('exception')
def test_trash_stack(self):
def f():
for i in range(5):
print(i) # line tracing will raise an exception at this line
def g(frame, why, extra):
if (why == 'line' and
frame.f_lineno == f.__code__.co_firstlineno + 2):
raise RuntimeError("i am crashing")
return g
sys.settrace(g)
try:
f()
except RuntimeError:
# the test is really that this doesn't segfault:
import gc
gc.collect()
else:
self.fail("exception not propagated")
def test_exception_arguments(self):
def f():
x = 0
# this should raise an error
x.no_such_attr
def g(frame, event, arg):
if (event == 'exception'):
type, exception, trace = arg
self.assertIsInstance(exception, Exception)
return g
existing = sys.gettrace()
try:
sys.settrace(g)
try:
f()
except AttributeError:
# this is expected
pass
finally:
sys.settrace(existing)
# 'Jump' tests: assigning to frame.f_lineno within a trace function
# moves the execution position - it's how debuggers implement a Jump
# command (aka. "Set next statement").
class JumpTracer:
"""Defines a trace function that jumps from one place to another."""
def __init__(self, function, jumpFrom, jumpTo, event='line',
decorated=False):
self.code = function.__code__
self.jumpFrom = jumpFrom
self.jumpTo = jumpTo
self.event = event
self.firstLine = None if decorated else self.code.co_firstlineno
self.done = False
def trace(self, frame, event, arg):
if self.done:
return
# frame.f_code.co_firstlineno is the first line of the decorator when
# 'function' is decorated and the decorator may be written using
# multiple physical lines when it is too long. Use the first line
# trace event in 'function' to find the first line of 'function'.
if (self.firstLine is None and frame.f_code == self.code and
event == 'line'):
self.firstLine = frame.f_lineno - 1
if (event == self.event and self.firstLine and
frame.f_lineno == self.firstLine + self.jumpFrom):
f = frame
while f is not None and f.f_code != self.code:
f = f.f_back
if f is not None:
# Cope with non-integer self.jumpTo (because of
# no_jump_to_non_integers below).
try:
frame.f_lineno = self.firstLine + self.jumpTo
except TypeError:
frame.f_lineno = self.jumpTo
self.done = True
return self.trace
# This verifies the line-numbers-must-be-integers rule.
def no_jump_to_non_integers(output):
try:
output.append(2)
except ValueError as e:
output.append('integer' in str(e))
# This verifies that you can't set f_lineno via _getframe or similar
# trickery.
def no_jump_without_trace_function():
try:
previous_frame = sys._getframe().f_back
previous_frame.f_lineno = previous_frame.f_lineno
except ValueError as e:
# This is the exception we wanted; make sure the error message
# talks about trace functions.
if 'trace' not in str(e):
raise
else:
# Something's wrong - the expected exception wasn't raised.
raise AssertionError("Trace-function-less jump failed to fail")
class JumpTestCase(unittest.TestCase):
def setUp(self):
self.addCleanup(sys.settrace, sys.gettrace())
sys.settrace(None)
def compare_jump_output(self, expected, received):
if received != expected:
self.fail( "Outputs don't match:\n" +
"Expected: " + repr(expected) + "\n" +
"Received: " + repr(received))
def run_test(self, func, jumpFrom, jumpTo, expected, error=None,
event='line', decorated=False):
tracer = JumpTracer(func, jumpFrom, jumpTo, event, decorated)
sys.settrace(tracer.trace)
output = []
if error is None:
func(output)
else:
with self.assertRaisesRegex(*error):
func(output)
sys.settrace(None)
self.compare_jump_output(expected, output)
def run_async_test(self, func, jumpFrom, jumpTo, expected, error=None,
event='line', decorated=False):
tracer = JumpTracer(func, jumpFrom, jumpTo, event, decorated)
sys.settrace(tracer.trace)
output = []
if error is None:
asyncio.run(func(output))
else:
with self.assertRaisesRegex(*error):
asyncio.run(func(output))
sys.settrace(None)
asyncio.set_event_loop_policy(None)
self.compare_jump_output(expected, output)
def jump_test(jumpFrom, jumpTo, expected, error=None, event='line'):
"""Decorator that creates a test that makes a jump
from one place to another in the following code.
"""
def decorator(func):
@wraps(func)
def test(self):
self.run_test(func, jumpFrom, jumpTo, expected,
error=error, event=event, decorated=True)
return test
return decorator
def async_jump_test(jumpFrom, jumpTo, expected, error=None, event='line'):
"""Decorator that creates a test that makes a jump
from one place to another in the following asynchronous code.
"""
def decorator(func):
@wraps(func)
def test(self):
self.run_async_test(func, jumpFrom, jumpTo, expected,
error=error, event=event, decorated=True)
return test
return decorator
## The first set of 'jump' tests are for things that are allowed:
@jump_test(1, 3, [3])
def test_jump_simple_forwards(output):
output.append(1)
output.append(2)
output.append(3)
@jump_test(2, 1, [1, 1, 2])
def test_jump_simple_backwards(output):
output.append(1)
output.append(2)
@jump_test(3, 5, [2, 5])
def test_jump_out_of_block_forwards(output):
for i in 1, 2:
output.append(2)
for j in [3]: # Also tests jumping over a block
output.append(4)
output.append(5)
@jump_test(6, 1, [1, 3, 5, 1, 3, 5, 6, 7])
def test_jump_out_of_block_backwards(output):
output.append(1)
for i in [1]:
output.append(3)
for j in [2]: # Also tests jumping over a block
output.append(5)
output.append(6)
output.append(7)
@async_jump_test(4, 5, [3, 5])
async def test_jump_out_of_async_for_block_forwards(output):
for i in [1]:
async for i in asynciter([1, 2]):
output.append(3)
output.append(4)
output.append(5)
@async_jump_test(5, 2, [2, 4, 2, 4, 5, 6])
async def test_jump_out_of_async_for_block_backwards(output):
for i in [1]:
output.append(2)
async for i in asynciter([1]):
output.append(4)
output.append(5)
output.append(6)
@jump_test(1, 2, [3])
def test_jump_to_codeless_line(output):
output.append(1)
# Jumping to this line should skip to the next one.
output.append(3)
@jump_test(2, 2, [1, 2, 3])
def test_jump_to_same_line(output):
output.append(1)
output.append(2)
output.append(3)
# Tests jumping within a finally block, and over one.
@jump_test(4, 9, [2, 9])
def test_jump_in_nested_finally(output):
try:
output.append(2)
finally:
output.append(4)
try:
output.append(6)
finally:
output.append(8)
output.append(9)
@jump_test(6, 7, [2, 7], (ZeroDivisionError, ''))
def test_jump_in_nested_finally_2(output):
try:
output.append(2)
1/0
return
finally:
output.append(6)
output.append(7)
output.append(8)
@jump_test(6, 11, [2, 11], (ZeroDivisionError, ''))
def test_jump_in_nested_finally_3(output):
try:
output.append(2)
1/0
return
finally:
output.append(6)
try:
output.append(8)
finally:
output.append(10)
output.append(11)
output.append(12)
@jump_test(5, 11, [2, 4, 12])
def test_jump_over_return_try_finally_in_finally_block(output):
try:
output.append(2)
finally:
output.append(4)
output.append(5)
return
try:
output.append(8)
finally:
output.append(10)
pass
output.append(12)
@jump_test(3, 4, [1, 4])
def test_jump_infinite_while_loop(output):
output.append(1)
while True:
output.append(3)
output.append(4)
@jump_test(2, 4, [4, 4])
def test_jump_forwards_into_while_block(output):
i = 1
output.append(2)
while i <= 2:
output.append(4)
i += 1
@jump_test(5, 3, [3, 3, 3, 5])
def test_jump_backwards_into_while_block(output):
i = 1
while i <= 2:
output.append(3)
i += 1
output.append(5)
@jump_test(2, 3, [1, 3])
def test_jump_forwards_out_of_with_block(output):
with tracecontext(output, 1):
output.append(2)
output.append(3)
@async_jump_test(2, 3, [1, 3])
async def test_jump_forwards_out_of_async_with_block(output):
async with asynctracecontext(output, 1):
output.append(2)
output.append(3)
@jump_test(3, 1, [1, 2, 1, 2, 3, -2])
def test_jump_backwards_out_of_with_block(output):
output.append(1)
with tracecontext(output, 2):
output.append(3)
@async_jump_test(3, 1, [1, 2, 1, 2, 3, -2])
async def test_jump_backwards_out_of_async_with_block(output):
output.append(1)
async with asynctracecontext(output, 2):
output.append(3)
@jump_test(2, 5, [5])
def test_jump_forwards_out_of_try_finally_block(output):
try:
output.append(2)
finally:
output.append(4)
output.append(5)
@jump_test(3, 1, [1, 1, 3, 5])
def test_jump_backwards_out_of_try_finally_block(output):
output.append(1)
try:
output.append(3)
finally:
output.append(5)
@jump_test(2, 6, [6])
def test_jump_forwards_out_of_try_except_block(output):
try:
output.append(2)
except:
output.append(4)
raise
output.append(6)
@jump_test(3, 1, [1, 1, 3])
def test_jump_backwards_out_of_try_except_block(output):
output.append(1)
try:
output.append(3)
except:
output.append(5)
raise
@jump_test(5, 7, [4, 7, 8])
def test_jump_between_except_blocks(output):
try:
1/0
except ZeroDivisionError:
output.append(4)
output.append(5)
except FloatingPointError:
output.append(7)
output.append(8)
@jump_test(5, 6, [4, 6, 7])
def test_jump_within_except_block(output):
try:
1/0
except:
output.append(4)
output.append(5)
output.append(6)
output.append(7)
@jump_test(2, 4, [1, 4, 5, -4])
def test_jump_across_with(output):
output.append(1)
with tracecontext(output, 2):
output.append(3)
with tracecontext(output, 4):
output.append(5)
@async_jump_test(2, 4, [1, 4, 5, -4])
async def test_jump_across_async_with(output):
output.append(1)
async with asynctracecontext(output, 2):
output.append(3)
async with asynctracecontext(output, 4):
output.append(5)
@jump_test(4, 5, [1, 3, 5, 6])
def test_jump_out_of_with_block_within_for_block(output):
output.append(1)
for i in [1]:
with tracecontext(output, 3):
output.append(4)
output.append(5)
output.append(6)
@async_jump_test(4, 5, [1, 3, 5, 6])
async def test_jump_out_of_async_with_block_within_for_block(output):
output.append(1)
for i in [1]:
async with asynctracecontext(output, 3):
output.append(4)
output.append(5)
output.append(6)
@jump_test(4, 5, [1, 2, 3, 5, -2, 6])
def test_jump_out_of_with_block_within_with_block(output):
output.append(1)
with tracecontext(output, 2):
with tracecontext(output, 3):
output.append(4)
output.append(5)
output.append(6)
@async_jump_test(4, 5, [1, 2, 3, 5, -2, 6])
async def test_jump_out_of_async_with_block_within_with_block(output):
output.append(1)
with tracecontext(output, 2):
async with asynctracecontext(output, 3):
output.append(4)
output.append(5)
output.append(6)
@jump_test(5, 6, [2, 4, 6, 7])
def test_jump_out_of_with_block_within_finally_block(output):
try:
output.append(2)
finally:
with tracecontext(output, 4):
output.append(5)
output.append(6)
output.append(7)
@async_jump_test(5, 6, [2, 4, 6, 7])
async def test_jump_out_of_async_with_block_within_finally_block(output):
try:
output.append(2)
finally:
async with asynctracecontext(output, 4):
output.append(5)
output.append(6)
output.append(7)
@jump_test(8, 11, [1, 3, 5, 11, 12])
def test_jump_out_of_complex_nested_blocks(output):
output.append(1)
for i in [1]:
output.append(3)
for j in [1, 2]:
output.append(5)
try:
for k in [1, 2]:
output.append(8)
finally:
output.append(10)
output.append(11)
output.append(12)
@jump_test(3, 5, [1, 2, 5])
def test_jump_out_of_with_assignment(output):
output.append(1)
with tracecontext(output, 2) \
as x:
output.append(4)
output.append(5)
@async_jump_test(3, 5, [1, 2, 5])
async def test_jump_out_of_async_with_assignment(output):
output.append(1)
async with asynctracecontext(output, 2) \
as x:
output.append(4)
output.append(5)
@jump_test(3, 6, [1, 6, 8, 9])
def test_jump_over_return_in_try_finally_block(output):
output.append(1)
try:
output.append(3)
if not output: # always false
return
output.append(6)
finally:
output.append(8)
output.append(9)
@jump_test(5, 8, [1, 3, 8, 10, 11, 13])
def test_jump_over_break_in_try_finally_block(output):
output.append(1)
while True:
output.append(3)
try:
output.append(5)
if not output: # always false
break
output.append(8)
finally:
output.append(10)
output.append(11)
break
output.append(13)
@jump_test(1, 7, [7, 8])
def test_jump_over_for_block_before_else(output):
output.append(1)
if not output: # always false
for i in [3]:
output.append(4)
else:
output.append(6)
output.append(7)
output.append(8)
@async_jump_test(1, 7, [7, 8])
async def test_jump_over_async_for_block_before_else(output):
output.append(1)
if not output: # always false
async for i in asynciter([3]):
output.append(4)
else:
output.append(6)
output.append(7)
output.append(8)
# The second set of 'jump' tests are for things that are not allowed:
@jump_test(2, 3, [1], (ValueError, 'after'))
def test_no_jump_too_far_forwards(output):
output.append(1)
output.append(2)
@jump_test(2, -2, [1], (ValueError, 'before'))
def test_no_jump_too_far_backwards(output):
output.append(1)
output.append(2)
# Test each kind of 'except' line.
@jump_test(2, 3, [4], (ValueError, 'except'))
def test_no_jump_to_except_1(output):
try:
output.append(2)
except:
output.append(4)
raise
@jump_test(2, 3, [4], (ValueError, 'except'))
def test_no_jump_to_except_2(output):
try:
output.append(2)
except ValueError:
output.append(4)
raise
@jump_test(2, 3, [4], (ValueError, 'except'))
def test_no_jump_to_except_3(output):
try:
output.append(2)
except ValueError as e:
output.append(4)
raise e
@jump_test(2, 3, [4], (ValueError, 'except'))
def test_no_jump_to_except_4(output):
try:
output.append(2)
except (ValueError, RuntimeError) as e:
output.append(4)
raise e
@jump_test(1, 3, [], (ValueError, 'into'))
def test_no_jump_forwards_into_for_block(output):
output.append(1)
for i in 1, 2:
output.append(3)
@async_jump_test(1, 3, [], (ValueError, 'into'))
async def test_no_jump_forwards_into_async_for_block(output):
output.append(1)
async for i in asynciter([1, 2]):
output.append(3)
@jump_test(3, 2, [2, 2], (ValueError, 'into'))
def test_no_jump_backwards_into_for_block(output):
for i in 1, 2:
output.append(2)
output.append(3)
@async_jump_test(3, 2, [2, 2], (ValueError, 'into'))
async def test_no_jump_backwards_into_async_for_block(output):
async for i in asynciter([1, 2]):
output.append(2)
output.append(3)
@jump_test(1, 3, [], (ValueError, 'into'))
def test_no_jump_forwards_into_with_block(output):
output.append(1)
with tracecontext(output, 2):
output.append(3)
@async_jump_test(1, 3, [], (ValueError, 'into'))
async def test_no_jump_forwards_into_async_with_block(output):
output.append(1)
async with asynctracecontext(output, 2):
output.append(3)
@jump_test(3, 2, [1, 2, -1], (ValueError, 'into'))
def test_no_jump_backwards_into_with_block(output):
with tracecontext(output, 1):
output.append(2)
output.append(3)
@async_jump_test(3, 2, [1, 2, -1], (ValueError, 'into'))
async def test_no_jump_backwards_into_async_with_block(output):
async with asynctracecontext(output, 1):
output.append(2)
output.append(3)
@jump_test(1, 3, [], (ValueError, 'into'))
def test_no_jump_forwards_into_try_finally_block(output):
output.append(1)
try:
output.append(3)
finally:
output.append(5)
@jump_test(5, 2, [2, 4], (ValueError, 'into'))
def test_no_jump_backwards_into_try_finally_block(output):
try:
output.append(2)
finally:
output.append(4)
output.append(5)
@jump_test(1, 3, [], (ValueError, 'into'))
def test_no_jump_forwards_into_try_except_block(output):
output.append(1)
try:
output.append(3)
except:
output.append(5)
raise
@jump_test(6, 2, [2], (ValueError, 'into'))
def test_no_jump_backwards_into_try_except_block(output):
try:
output.append(2)
except:
output.append(4)
raise
output.append(6)
# 'except' with a variable creates an implicit finally block
@jump_test(5, 7, [4], (ValueError, 'into'))
def test_no_jump_between_except_blocks_2(output):
try:
1/0
except ZeroDivisionError:
output.append(4)
output.append(5)
except FloatingPointError as e:
output.append(7)
output.append(8)
@jump_test(1, 5, [], (ValueError, "into a 'finally'"))
def test_no_jump_into_finally_block(output):
output.append(1)
try:
output.append(3)
finally:
output.append(5)
@jump_test(3, 6, [2, 5, 6], (ValueError, "into a 'finally'"))
def test_no_jump_into_finally_block_from_try_block(output):
try:
output.append(2)
output.append(3)
finally: # still executed if the jump is failed
output.append(5)
output.append(6)
output.append(7)
@jump_test(5, 1, [1, 3], (ValueError, "out of a 'finally'"))
def test_no_jump_out_of_finally_block(output):
output.append(1)
try:
output.append(3)
finally:
output.append(5)
@jump_test(1, 5, [], (ValueError, "into an 'except'"))
def test_no_jump_into_bare_except_block(output):
output.append(1)
try:
output.append(3)
except:
output.append(5)
@jump_test(1, 5, [], (ValueError, "into an 'except'"))
def test_no_jump_into_qualified_except_block(output):
output.append(1)
try:
output.append(3)
except Exception:
output.append(5)
@jump_test(3, 6, [2, 5, 6], (ValueError, "into an 'except'"))
def test_no_jump_into_bare_except_block_from_try_block(output):
try:
output.append(2)
output.append(3)
except: # executed if the jump is failed
output.append(5)
output.append(6)
raise
output.append(8)
@jump_test(3, 6, [2], (ValueError, "into an 'except'"))
def test_no_jump_into_qualified_except_block_from_try_block(output):
try:
output.append(2)
output.append(3)
except ZeroDivisionError:
output.append(5)
output.append(6)
raise
output.append(8)
@jump_test(7, 1, [1, 3, 6], (ValueError, "out of an 'except'"))
def test_no_jump_out_of_bare_except_block(output):
output.append(1)
try:
output.append(3)
1/0
except:
output.append(6)
output.append(7)
@jump_test(7, 1, [1, 3, 6], (ValueError, "out of an 'except'"))
def test_no_jump_out_of_qualified_except_block(output):
output.append(1)
try:
output.append(3)
1/0
except Exception:
output.append(6)
output.append(7)
@jump_test(3, 5, [1, 2, -2], (ValueError, 'into'))
def test_no_jump_between_with_blocks(output):
output.append(1)
with tracecontext(output, 2):
output.append(3)
with tracecontext(output, 4):
output.append(5)
@async_jump_test(3, 5, [1, 2, -2], (ValueError, 'into'))
async def test_no_jump_between_async_with_blocks(output):
output.append(1)
async with asynctracecontext(output, 2):
output.append(3)
async with asynctracecontext(output, 4):
output.append(5)
@jump_test(5, 7, [2, 4], (ValueError, 'finally'))
def test_no_jump_over_return_out_of_finally_block(output):
try:
output.append(2)
finally:
output.append(4)
output.append(5)
return
output.append(7)
@jump_test(7, 4, [1, 6], (ValueError, 'into'))
def test_no_jump_into_for_block_before_else(output):
output.append(1)
if not output: # always false
for i in [3]:
output.append(4)
else:
output.append(6)
output.append(7)
output.append(8)
@async_jump_test(7, 4, [1, 6], (ValueError, 'into'))
async def test_no_jump_into_async_for_block_before_else(output):
output.append(1)
if not output: # always false
async for i in asynciter([3]):
output.append(4)
else:
output.append(6)
output.append(7)
output.append(8)
def test_no_jump_to_non_integers(self):
self.run_test(no_jump_to_non_integers, 2, "Spam", [True])
def test_no_jump_without_trace_function(self):
# Must set sys.settrace(None) in setUp(), else condition is not
# triggered.
no_jump_without_trace_function()
def test_large_function(self):
d = {}
exec("""def f(output): # line 0
x = 0 # line 1
y = 1 # line 2
''' # line 3
%s # lines 4-1004
''' # line 1005
x += 1 # line 1006
output.append(x) # line 1007
return""" % ('\n' * 1000,), d)
f = d['f']
self.run_test(f, 2, 1007, [0])
def test_jump_to_firstlineno(self):
# This tests that PDB can jump back to the first line in a
# file. See issue #1689458. It can only be triggered in a
# function call if the function is defined on a single line.
code = compile("""
# Comments don't count.
output.append(2) # firstlineno is here.
output.append(3)
output.append(4)
""", "<fake module>", "exec")
class fake_function:
__code__ = code
tracer = JumpTracer(fake_function, 2, 0)
sys.settrace(tracer.trace)
namespace = {"output": []}
exec(code, namespace)
sys.settrace(None)
self.compare_jump_output([2, 3, 2, 3, 4], namespace["output"])
@jump_test(2, 3, [1], event='call', error=(ValueError, "can't jump from"
" the 'call' trace event of a new frame"))
def test_no_jump_from_call(output):
output.append(1)
def nested():
output.append(3)
nested()
output.append(5)
@jump_test(2, 1, [1], event='return', error=(ValueError,
"can only jump from a 'line' trace event"))
def test_no_jump_from_return_event(output):
output.append(1)
return
@jump_test(2, 1, [1], event='exception', error=(ValueError,
"can only jump from a 'line' trace event"))
def test_no_jump_from_exception_event(output):
output.append(1)
1 / 0
@jump_test(3, 2, [2], event='return', error=(ValueError,
"can't jump from a 'yield' statement"))
def test_no_jump_from_yield(output):
def gen():
output.append(2)
yield 3
next(gen())
output.append(5)
if __name__ == "__main__":
unittest.main()
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