blob: 3a013b0459d13d538f56570492fd91b3d717f883 [file] [log] [blame]
"""Oddball cases for testing coverage.py"""
import os, sys
import coverage
from tests.coveragetest import CoverageTest
from tests import osinfo
class ThreadingTest(CoverageTest):
"""Tests of the threading support."""
def test_threading(self):
self.check_coverage("""\
import threading
def fromMainThread():
return "called from main thread"
def fromOtherThread():
return "called from other thread"
def neverCalled():
return "no one calls me"
other = threading.Thread(target=fromOtherThread)
other.start()
fromMainThread()
other.join()
""",
[1,3,4,6,7,9,10,12,13,14,15], "10")
def test_thread_run(self):
self.check_coverage("""\
import threading
class TestThread(threading.Thread):
def run(self):
self.a = 5
self.do_work()
self.a = 7
def do_work(self):
self.a = 10
thd = TestThread()
thd.start()
thd.join()
""",
[1,3,4,5,6,7,9,10,12,13,14], "")
class RecursionTest(CoverageTest):
"""Check what happens when recursive code gets near limits."""
def test_short_recursion(self):
# We can definitely get close to 500 stack frames.
self.check_coverage("""\
def recur(n):
if n == 0:
return 0
else:
return recur(n-1)+1
recur(495) # We can get at least this many stack frames.
i = 8 # and this line will be traced
""",
[1,2,3,5,7,8], "")
def test_long_recursion(self):
# We can't finish a very deep recursion, but we don't crash.
with self.assertRaises(RuntimeError):
self.check_coverage("""\
def recur(n):
if n == 0:
return 0
else:
return recur(n-1)+1
recur(100000) # This is definitely too many frames.
""",
[1,2,3,5,7], ""
)
def test_long_recursion_recovery(self):
# Test the core of bug 93: http://bitbucket.org/ned/coveragepy/issue/93
# When recovering from a stack overflow, the Python trace function is
# disabled, but the C trace function is not. So if we're using a
# Python trace function, we won't trace anything after the stack
# overflow, and there should be a warning about it. If we're using
# the C trace function, only line 3 will be missing, and all else
# will be traced.
self.make_file("recur.py", """\
def recur(n):
if n == 0:
return 0 # never hit
else:
return recur(n-1)+1
try:
recur(100000) # This is definitely too many frames.
except RuntimeError:
i = 10
i = 11
""")
cov = coverage.coverage()
self.start_import_stop(cov, "recur")
pytrace = (cov.collector.tracer_name() == "PyTracer")
expected_missing = [3]
if pytrace:
expected_missing += [9,10,11]
_, statements, missing, _ = cov.analysis("recur.py")
self.assertEqual(statements, [1,2,3,5,7,8,9,10,11])
self.assertEqual(missing, expected_missing)
# Get a warning about the stackoverflow effect on the tracing function.
if pytrace:
self.assertEqual(cov._warnings,
["Trace function changed, measurement is likely wrong: None"]
)
else:
self.assertEqual(cov._warnings, [])
class MemoryLeakTest(CoverageTest):
"""Attempt the impossible: test that memory doesn't leak.
Note: this test is truly unusual, and has had a colorful history. See
for example: https://bitbucket.org/ned/coveragepy/issue/186
It may still fail occasionally, especially on PyPy.
"""
def test_for_leaks(self):
# Our original bad memory leak only happened on line numbers > 255, so
# make a code object with more lines than that. Ugly string mumbo
# jumbo to get 300 blank lines at the beginning..
code = """\
# blank line\n""" * 300 + """\
def once(x): # line 301
if x % 100 == 0:
raise Exception("100!")
elif x % 2:
return 10
else: # line 306
return 11
i = 0 # Portable loop without alloc'ing memory.
while i < ITERS:
try:
once(i)
except:
pass
i += 1 # line 315
"""
lines = list(range(301, 315))
lines.remove(306) # Line 306 is the "else".
# This is a non-deterministic test, so try it a few times, and fail it
# only if it predominantly fails.
fails = 0
for _ in range(10):
ram_0 = osinfo.process_ram()
self.check_coverage(code.replace("ITERS", "10"), lines, "")
ram_10 = osinfo.process_ram()
self.check_coverage(code.replace("ITERS", "10000"), lines, "")
ram_10k = osinfo.process_ram()
# Running the code 10k times shouldn't grow the ram much more than
# running it 10 times.
ram_growth = (ram_10k - ram_10) - (ram_10 - ram_0)
if ram_growth > 100000:
fails += 1
if fails > 8: # pragma: only failure
self.fail("RAM grew by %d" % (ram_growth))
class PyexpatTest(CoverageTest):
"""Pyexpat screws up tracing. Make sure we've counter-defended properly."""
def test_pyexpat(self):
# pyexpat calls the trace function explicitly (inexplicably), and does
# it wrong for exceptions. Parsing a DOCTYPE for some reason throws
# an exception internally, and triggers its wrong behavior. This test
# checks that our fake PyTrace_RETURN hack in tracer.c works. It will
# also detect if the pyexpat bug is fixed unbeknownst to us, meaning
# we'd see two RETURNs where there should only be one.
self.make_file("trydom.py", """\
import xml.dom.minidom
XML = '''\\
<!DOCTYPE fooey SYSTEM "http://www.example.com/example.dtd">
<root><child/><child/></root>
'''
def foo():
dom = xml.dom.minidom.parseString(XML)
assert len(dom.getElementsByTagName('child')) == 2
a = 11
foo()
""")
self.make_file("outer.py", "\n"*100 + "import trydom\na = 102\n")
cov = coverage.coverage()
cov.erase()
# Import the python file, executing it.
self.start_import_stop(cov, "outer")
_, statements, missing, _ = cov.analysis("trydom.py")
self.assertEqual(statements, [1,3,8,9,10,11,13])
self.assertEqual(missing, [])
_, statements, missing, _ = cov.analysis("outer.py")
self.assertEqual(statements, [101,102])
self.assertEqual(missing, [])
class ExceptionTest(CoverageTest):
"""I suspect different versions of Python deal with exceptions differently
in the trace function.
"""
def test_exception(self):
# Python 2.3's trace function doesn't get called with "return" if the
# scope is exiting due to an exception. This confounds our trace
# function which relies on scope announcements to track which files to
# trace.
#
# This test is designed to sniff this out. Each function in the call
# stack is in a different file, to try to trip up the tracer. Each
# file has active lines in a different range so we'll see if the lines
# get attributed to the wrong file.
self.make_file("oops.py", """\
def oops(args):
a = 2
raise Exception("oops")
a = 4
""")
self.make_file("fly.py", "\n"*100 + """\
def fly(calls):
a = 2
calls[0](calls[1:])
a = 4
""")
self.make_file("catch.py", "\n"*200 + """\
def catch(calls):
try:
a = 3
calls[0](calls[1:])
a = 5
except:
a = 7
""")
self.make_file("doit.py", "\n"*300 + """\
def doit(calls):
try:
calls[0](calls[1:])
except:
a = 5
""")
# Import all the modules before starting coverage, so the def lines
# won't be in all the results.
for mod in "oops fly catch doit".split():
self.import_local_file(mod)
# Each run nests the functions differently to get different
# combinations of catching exceptions and letting them fly.
runs = [
("doit fly oops", {
'doit.py': [302,303,304,305],
'fly.py': [102,103],
'oops.py': [2,3],
}),
("doit catch oops", {
'doit.py': [302,303],
'catch.py': [202,203,204,206,207],
'oops.py': [2,3],
}),
("doit fly catch oops", {
'doit.py': [302,303],
'fly.py': [102,103,104],
'catch.py': [202,203,204,206,207],
'oops.py': [2,3],
}),
("doit catch fly oops", {
'doit.py': [302,303],
'catch.py': [202,203,204,206,207],
'fly.py': [102,103],
'oops.py': [2,3],
}),
]
for callnames, lines_expected in runs:
# Make the list of functions we'll call for this test.
calls = [getattr(sys.modules[cn], cn) for cn in callnames.split()]
cov = coverage.coverage()
cov.start()
# Call our list of functions: invoke the first, with the rest as
# an argument.
calls[0](calls[1:]) # pragma: nested
cov.stop() # pragma: nested
# Clean the line data and compare to expected results.
# The filenames are absolute, so keep just the base.
cov._harvest_data() # private! sshhh...
lines = cov.data.line_data()
clean_lines = {}
for f, llist in lines.items():
# f is a path to a python module, so we drop the '.py' to get
# a callname
basename = os.path.basename(f)
assert basename.endswith(".py")
if basename[:-3] in callnames:
clean_lines[basename] = llist
self.assertEqual(clean_lines, lines_expected)
class DoctestTest(CoverageTest):
"""Tests invoked with doctest should measure properly."""
def setUp(self):
super(DoctestTest, self).setUp()
# Oh, the irony! This test case exists because Python 2.4's
# doctest module doesn't play well with coverage. But nose fixes
# the problem by monkeypatching doctest. I want to undo the
# monkeypatch to be sure I'm getting the doctest module that users
# of coverage will get. Deleting the imported module here is
# enough: when the test imports doctest again, it will get a fresh
# copy without the monkeypatch.
del sys.modules['doctest']
def test_doctest(self):
self.check_coverage('''\
def return_arg_or_void(arg):
"""If <arg> is None, return "Void"; otherwise return <arg>
>>> return_arg_or_void(None)
'Void'
>>> return_arg_or_void("arg")
'arg'
>>> return_arg_or_void("None")
'None'
"""
if arg is None:
return "Void"
else:
return arg
import doctest, sys
doctest.testmod(sys.modules[__name__]) # we're not __main__ :(
''',
[1,11,12,14,16,17], "")
class GettraceTest(CoverageTest):
"""Tests that we work properly with `sys.gettrace()`."""
def test_round_trip(self):
self.check_coverage('''\
import sys
def foo(n):
return 3*n
def bar(n):
return 5*n
a = foo(6)
sys.settrace(sys.gettrace())
a = bar(8)
''',
[1,2,3,4,5,6,7,8], "")
def test_multi_layers(self):
self.check_coverage('''\
import sys
def level1():
a = 3
level2()
b = 5
def level2():
c = 7
sys.settrace(sys.gettrace())
d = 9
e = 10
level1()
f = 12
''',
[1,2,3,4,5,6,7,8,9,10,11,12], "")