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-rw-r--r--Lib/test/test_trace.py790
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diff --git a/Lib/test/test_trace.py b/Lib/test/test_trace.py
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+# Testing the line trace facility.
+
+from test import support
+import unittest
+import sys
+import difflib
+import gc
+
+# 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 caluse) under what conditions do you set a line number
+# following that clause?
+
+
+# The entire "while 0:" statement is optimized away. No code
+# exists for it, so the line numbers skip directly from "del x"
+# to "x = 1".
+def arigo_example():
+ x = 1
+ del x
+ while 0:
+ pass
+ x = 1
+
+arigo_example.events = [(0, 'call'),
+ (1, 'line'),
+ (2, 'line'),
+ (5, 'line'),
+ (5, '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 as exc:
+ x = 1
+
+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 as exc:
+ 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'),
+ (4, '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):
+ self.events = []
+ def trace(self, frame, event, arg):
+ self.events.append((frame.f_lineno, event))
+ return self.trace
+ def traceWithGenexp(self, frame, event, arg):
+ (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()
+
+ def tearDown(self):
+ if self.using_gc:
+ gc.enable()
+
+ 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 = 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 = Tracer()
+ func(tracer.trace)
+ sys.settrace(None)
+ self.compare_events(func.__code__.co_firstlineno,
+ tracer.events, func.events)
+
+ def set_and_retrieve_none(self):
+ sys.settrace(None)
+ assert sys.gettrace() is None
+
+ def 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_arigo(self):
+ self.run_test(arigo_example)
+ 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 = 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: False
+ else: 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')])
+
+
+class RaisingTraceFuncTestCase(unittest.TestCase):
+ 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 thrown!")
+ 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")
+
+
+# '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,
+ with the source and destination lines of the jump being defined by
+ the 'jump' property of the function under test."""
+
+ def __init__(self, function):
+ self.function = function
+ self.jumpFrom = function.jump[0]
+ self.jumpTo = function.jump[1]
+ self.done = False
+
+ def trace(self, frame, event, arg):
+ if not self.done and frame.f_code == self.function.__code__:
+ firstLine = frame.f_code.co_firstlineno
+ if event == 'line' and frame.f_lineno == firstLine + self.jumpFrom:
+ # Cope with non-integer self.jumpTo (because of
+ # no_jump_to_non_integers below).
+ try:
+ frame.f_lineno = firstLine + self.jumpTo
+ except TypeError:
+ frame.f_lineno = self.jumpTo
+ self.done = True
+ return self.trace
+
+# The first set of 'jump' tests are for things that are allowed:
+
+def jump_simple_forwards(output):
+ output.append(1)
+ output.append(2)
+ output.append(3)
+
+jump_simple_forwards.jump = (1, 3)
+jump_simple_forwards.output = [3]
+
+def jump_simple_backwards(output):
+ output.append(1)
+ output.append(2)
+
+jump_simple_backwards.jump = (2, 1)
+jump_simple_backwards.output = [1, 1, 2]
+
+def 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_out_of_block_forwards.jump = (3, 5)
+jump_out_of_block_forwards.output = [2, 5]
+
+def 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)
+
+jump_out_of_block_backwards.jump = (6, 1)
+jump_out_of_block_backwards.output = [1, 3, 5, 1, 3, 5, 6, 7]
+
+def jump_to_codeless_line(output):
+ output.append(1)
+ # Jumping to this line should skip to the next one.
+ output.append(3)
+
+jump_to_codeless_line.jump = (1, 2)
+jump_to_codeless_line.output = [3]
+
+def jump_to_same_line(output):
+ output.append(1)
+ output.append(2)
+ output.append(3)
+
+jump_to_same_line.jump = (2, 2)
+jump_to_same_line.output = [1, 2, 3]
+
+# Tests jumping within a finally block, and over one.
+def 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_in_nested_finally.jump = (4, 9)
+jump_in_nested_finally.output = [2, 9]
+
+# The second set of 'jump' tests are for things that are not allowed:
+
+def no_jump_too_far_forwards(output):
+ try:
+ output.append(2)
+ output.append(3)
+ except ValueError as e:
+ output.append('after' in str(e))
+
+no_jump_too_far_forwards.jump = (3, 6)
+no_jump_too_far_forwards.output = [2, True]
+
+def no_jump_too_far_backwards(output):
+ try:
+ output.append(2)
+ output.append(3)
+ except ValueError as e:
+ output.append('before' in str(e))
+
+no_jump_too_far_backwards.jump = (3, -1)
+no_jump_too_far_backwards.output = [2, True]
+
+# Test each kind of 'except' line.
+def no_jump_to_except_1(output):
+ try:
+ output.append(2)
+ except:
+ e = sys.exc_info()[1]
+ output.append('except' in str(e))
+
+no_jump_to_except_1.jump = (2, 3)
+no_jump_to_except_1.output = [True]
+
+def no_jump_to_except_2(output):
+ try:
+ output.append(2)
+ except ValueError:
+ e = sys.exc_info()[1]
+ output.append('except' in str(e))
+
+no_jump_to_except_2.jump = (2, 3)
+no_jump_to_except_2.output = [True]
+
+def no_jump_to_except_3(output):
+ try:
+ output.append(2)
+ except ValueError as e:
+ output.append('except' in str(e))
+
+no_jump_to_except_3.jump = (2, 3)
+no_jump_to_except_3.output = [True]
+
+def no_jump_to_except_4(output):
+ try:
+ output.append(2)
+ except (ValueError, RuntimeError) as e:
+ output.append('except' in str(e))
+
+no_jump_to_except_4.jump = (2, 3)
+no_jump_to_except_4.output = [True]
+
+def no_jump_forwards_into_block(output):
+ try:
+ output.append(2)
+ for i in 1, 2:
+ output.append(4)
+ except ValueError as e:
+ output.append('into' in str(e))
+
+no_jump_forwards_into_block.jump = (2, 4)
+no_jump_forwards_into_block.output = [True]
+
+def no_jump_backwards_into_block(output):
+ try:
+ for i in 1, 2:
+ output.append(3)
+ output.append(4)
+ except ValueError as e:
+ output.append('into' in str(e))
+
+no_jump_backwards_into_block.jump = (4, 3)
+no_jump_backwards_into_block.output = [3, 3, True]
+
+def no_jump_into_finally_block(output):
+ try:
+ try:
+ output.append(3)
+ x = 1
+ finally:
+ output.append(6)
+ except ValueError as e:
+ output.append('finally' in str(e))
+
+no_jump_into_finally_block.jump = (4, 6)
+no_jump_into_finally_block.output = [3, 6, True] # The 'finally' still runs
+
+def no_jump_out_of_finally_block(output):
+ try:
+ try:
+ output.append(3)
+ finally:
+ output.append(5)
+ output.append(6)
+ except ValueError as e:
+ output.append('finally' in str(e))
+
+no_jump_out_of_finally_block.jump = (5, 1)
+no_jump_out_of_finally_block.output = [3, True]
+
+# 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))
+
+no_jump_to_non_integers.jump = (2, "Spam")
+no_jump_to_non_integers.output = [True]
+
+# 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 RuntimeError("Trace-function-less jump failed to fail")
+
+
+class JumpTestCase(unittest.TestCase):
+ 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):
+ tracer = JumpTracer(func)
+ sys.settrace(tracer.trace)
+ output = []
+ func(output)
+ sys.settrace(None)
+ self.compare_jump_output(func.output, output)
+
+ def test_01_jump_simple_forwards(self):
+ self.run_test(jump_simple_forwards)
+ def test_02_jump_simple_backwards(self):
+ self.run_test(jump_simple_backwards)
+ def test_03_jump_out_of_block_forwards(self):
+ self.run_test(jump_out_of_block_forwards)
+ def test_04_jump_out_of_block_backwards(self):
+ self.run_test(jump_out_of_block_backwards)
+ def test_05_jump_to_codeless_line(self):
+ self.run_test(jump_to_codeless_line)
+ def test_06_jump_to_same_line(self):
+ self.run_test(jump_to_same_line)
+ def test_07_jump_in_nested_finally(self):
+ self.run_test(jump_in_nested_finally)
+ def test_08_no_jump_too_far_forwards(self):
+ self.run_test(no_jump_too_far_forwards)
+ def test_09_no_jump_too_far_backwards(self):
+ self.run_test(no_jump_too_far_backwards)
+ def test_10_no_jump_to_except_1(self):
+ self.run_test(no_jump_to_except_1)
+ def test_11_no_jump_to_except_2(self):
+ self.run_test(no_jump_to_except_2)
+ def test_12_no_jump_to_except_3(self):
+ self.run_test(no_jump_to_except_3)
+ def test_13_no_jump_to_except_4(self):
+ self.run_test(no_jump_to_except_4)
+ def test_14_no_jump_forwards_into_block(self):
+ self.run_test(no_jump_forwards_into_block)
+ def test_15_no_jump_backwards_into_block(self):
+ self.run_test(no_jump_backwards_into_block)
+ def test_16_no_jump_into_finally_block(self):
+ self.run_test(no_jump_into_finally_block)
+ def test_17_no_jump_out_of_finally_block(self):
+ self.run_test(no_jump_out_of_finally_block)
+ def test_18_no_jump_to_non_integers(self):
+ self.run_test(no_jump_to_non_integers)
+ def test_19_no_jump_without_trace_function(self):
+ no_jump_without_trace_function()
+
+ def test_20_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']
+
+ f.jump = (2, 1007)
+ f.output = [0]
+ self.run_test(f)
+
+ 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
+ jump = (2, 0)
+ tracer = JumpTracer(fake_function)
+ sys.settrace(tracer.trace)
+ namespace = {"output": []}
+ exec(code, namespace)
+ sys.settrace(None)
+ self.compare_jump_output([2, 3, 2, 3, 4], namespace["output"])
+
+
+def test_main():
+ support.run_unittest(
+ TraceTestCase,
+ RaisingTraceFuncTestCase,
+ JumpTestCase
+ )
+
+if __name__ == "__main__":
+ test_main()
generated by cgit v0.12 at 2024-11-24 23:30:55 (GMT)