cpython/Lib/test/test_sys.py

# -*- coding: iso-8859-1 -*-
import unittest, test.test_support
import sys, cStringIO, os
import struct

class SysModuleTest(unittest.TestCase):

    def test_original_displayhook(self):
        import __builtin__
        savestdout = sys.stdout
        out = cStringIO.StringIO()
        sys.stdout = out

        dh = sys.__displayhook__

        self.assertRaises(TypeError, dh)
        if hasattr(__builtin__, "_"):
            del __builtin__._

        dh(None)
        self.assertEqual(out.getvalue(), "")
        self.assert_(not hasattr(__builtin__, "_"))
        dh(42)
        self.assertEqual(out.getvalue(), "42\n")
        self.assertEqual(__builtin__._, 42)

        del sys.stdout
        self.assertRaises(RuntimeError, dh, 42)

        sys.stdout = savestdout

    def test_lost_displayhook(self):
        olddisplayhook = sys.displayhook
        del sys.displayhook
        code = compile("42", "<string>", "single")
        self.assertRaises(RuntimeError, eval, code)
        sys.displayhook = olddisplayhook

    def test_custom_displayhook(self):
        olddisplayhook = sys.displayhook
        def baddisplayhook(obj):
            raise ValueError
        sys.displayhook = baddisplayhook
        code = compile("42", "<string>", "single")
        self.assertRaises(ValueError, eval, code)
        sys.displayhook = olddisplayhook

    def test_original_excepthook(self):
        savestderr = sys.stderr
        err = cStringIO.StringIO()
        sys.stderr = err

        eh = sys.__excepthook__

        self.assertRaises(TypeError, eh)
        try:
            raise ValueError(42)
        except ValueError, exc:
            eh(*sys.exc_info())

        sys.stderr = savestderr
        self.assert_(err.getvalue().endswith("ValueError: 42\n"))

    # FIXME: testing the code for a lost or replaced excepthook in
    # Python/pythonrun.c::PyErr_PrintEx() is tricky.

    def test_exc_clear(self):
        self.assertRaises(TypeError, sys.exc_clear, 42)

        # Verify that exc_info is present and matches exc, then clear it, and
        # check that it worked.
        def clear_check(exc):
            typ, value, traceback = sys.exc_info()
            self.assert_(typ is not None)
            self.assert_(value is exc)
            self.assert_(traceback is not None)

            sys.exc_clear()

            typ, value, traceback = sys.exc_info()
            self.assert_(typ is None)
            self.assert_(value is None)
            self.assert_(traceback is None)

        def clear():
            try:
                raise ValueError, 42
            except ValueError, exc:
                clear_check(exc)

        # Raise an exception and check that it can be cleared
        clear()

        # Verify that a frame currently handling an exception is
        # unaffected by calling exc_clear in a nested frame.
        try:
            raise ValueError, 13
        except ValueError, exc:
            typ1, value1, traceback1 = sys.exc_info()
            clear()
            typ2, value2, traceback2 = sys.exc_info()

            self.assert_(typ1 is typ2)
            self.assert_(value1 is exc)
            self.assert_(value1 is value2)
            self.assert_(traceback1 is traceback2)

        # Check that an exception can be cleared outside of an except block
        clear_check(exc)

    def test_exit(self):
        self.assertRaises(TypeError, sys.exit, 42, 42)

        # call without argument
        try:
            sys.exit(0)
        except SystemExit, exc:
            self.assertEquals(exc.code, 0)
        except:
            self.fail("wrong exception")
        else:
            self.fail("no exception")

        # call with tuple argument with one entry
        # entry will be unpacked
        try:
            sys.exit(42)
        except SystemExit, exc:
            self.assertEquals(exc.code, 42)
        except:
            self.fail("wrong exception")
        else:
            self.fail("no exception")

        # call with integer argument
        try:
            sys.exit((42,))
        except SystemExit, exc:
            self.assertEquals(exc.code, 42)
        except:
            self.fail("wrong exception")
        else:
            self.fail("no exception")

        # call with string argument
        try:
            sys.exit("exit")
        except SystemExit, exc:
            self.assertEquals(exc.code, "exit")
        except:
            self.fail("wrong exception")
        else:
            self.fail("no exception")

        # call with tuple argument with two entries
        try:
            sys.exit((17, 23))
        except SystemExit, exc:
            self.assertEquals(exc.code, (17, 23))
        except:
            self.fail("wrong exception")
        else:
            self.fail("no exception")

        # test that the exit machinery handles SystemExits properly
        import subprocess
        # both unnormalized...
        rc = subprocess.call([sys.executable, "-c",
                              "raise SystemExit, 46"])
        self.assertEqual(rc, 46)
        # ... and normalized
        rc = subprocess.call([sys.executable, "-c",
                              "raise SystemExit(47)"])
        self.assertEqual(rc, 47)


    def test_getdefaultencoding(self):
        if test.test_support.have_unicode:
            self.assertRaises(TypeError, sys.getdefaultencoding, 42)
            # can't check more than the type, as the user might have changed it
            self.assert_(isinstance(sys.getdefaultencoding(), str))

    # testing sys.settrace() is done in test_trace.py
    # testing sys.setprofile() is done in test_profile.py

    def test_setcheckinterval(self):
        self.assertRaises(TypeError, sys.setcheckinterval)
        orig = sys.getcheckinterval()
        for n in 0, 100, 120, orig: # orig last to restore starting state
            sys.setcheckinterval(n)
            self.assertEquals(sys.getcheckinterval(), n)

    def test_recursionlimit(self):
        self.assertRaises(TypeError, sys.getrecursionlimit, 42)
        oldlimit = sys.getrecursionlimit()
        self.assertRaises(TypeError, sys.setrecursionlimit)
        self.assertRaises(ValueError, sys.setrecursionlimit, -42)
        sys.setrecursionlimit(10000)
        self.assertEqual(sys.getrecursionlimit(), 10000)
        sys.setrecursionlimit(oldlimit)

    def test_getwindowsversion(self):
        if hasattr(sys, "getwindowsversion"):
            v = sys.getwindowsversion()
            self.assert_(isinstance(v, tuple))
            self.assertEqual(len(v), 5)
            self.assert_(isinstance(v[0], int))
            self.assert_(isinstance(v[1], int))
            self.assert_(isinstance(v[2], int))
            self.assert_(isinstance(v[3], int))
            self.assert_(isinstance(v[4], str))

    def test_dlopenflags(self):
        if hasattr(sys, "setdlopenflags"):
            self.assert_(hasattr(sys, "getdlopenflags"))
            self.assertRaises(TypeError, sys.getdlopenflags, 42)
            oldflags = sys.getdlopenflags()
            self.assertRaises(TypeError, sys.setdlopenflags)
            sys.setdlopenflags(oldflags+1)
            self.assertEqual(sys.getdlopenflags(), oldflags+1)
            sys.setdlopenflags(oldflags)

    def test_refcount(self):
        self.assertRaises(TypeError, sys.getrefcount)
        c = sys.getrefcount(None)
        n = None
        self.assertEqual(sys.getrefcount(None), c+1)
        del n
        self.assertEqual(sys.getrefcount(None), c)
        if hasattr(sys, "gettotalrefcount"):
            self.assert_(isinstance(sys.gettotalrefcount(), int))

    def test_getframe(self):
        self.assertRaises(TypeError, sys._getframe, 42, 42)
        self.assertRaises(ValueError, sys._getframe, 2000000000)
        self.assert_(
            SysModuleTest.test_getframe.im_func.func_code \
            is sys._getframe().f_code
        )

    # sys._current_frames() is a CPython-only gimmick.
    def test_current_frames(self):
        have_threads = True
        try:
            import thread
        except ImportError:
            have_threads = False

        if have_threads:
            self.current_frames_with_threads()
        else:
            self.current_frames_without_threads()

    # Test sys._current_frames() in a WITH_THREADS build.
    def current_frames_with_threads(self):
        import threading, thread
        import traceback

        # Spawn a thread that blocks at a known place.  Then the main
        # thread does sys._current_frames(), and verifies that the frames
        # returned make sense.
        entered_g = threading.Event()
        leave_g = threading.Event()
        thread_info = []  # the thread's id

        def f123():
            g456()

        def g456():
            thread_info.append(thread.get_ident())
            entered_g.set()
            leave_g.wait()

        t = threading.Thread(target=f123)
        t.start()
        entered_g.wait()

        # At this point, t has finished its entered_g.set(), although it's
        # impossible to guess whether it's still on that line or has moved on
        # to its leave_g.wait().
        self.assertEqual(len(thread_info), 1)
        thread_id = thread_info[0]

        d = sys._current_frames()

        main_id = thread.get_ident()
        self.assert_(main_id in d)
        self.assert_(thread_id in d)

        # Verify that the captured main-thread frame is _this_ frame.
        frame = d.pop(main_id)
        self.assert_(frame is sys._getframe())

        # Verify that the captured thread frame is blocked in g456, called
        # from f123.  This is a litte tricky, since various bits of
        # threading.py are also in the thread's call stack.
        frame = d.pop(thread_id)
        stack = traceback.extract_stack(frame)
        for i, (filename, lineno, funcname, sourceline) in enumerate(stack):
            if funcname == "f123":
                break
        else:
            self.fail("didn't find f123() on thread's call stack")

        self.assertEqual(sourceline, "g456()")

        # And the next record must be for g456().
        filename, lineno, funcname, sourceline = stack[i+1]
        self.assertEqual(funcname, "g456")
        self.assert_(sourceline in ["leave_g.wait()", "entered_g.set()"])

        # Reap the spawned thread.
        leave_g.set()
        t.join()

    # Test sys._current_frames() when thread support doesn't exist.
    def current_frames_without_threads(self):
        # Not much happens here:  there is only one thread, with artificial
        # "thread id" 0.
        d = sys._current_frames()
        self.assertEqual(len(d), 1)
        self.assert_(0 in d)
        self.assert_(d[0] is sys._getframe())

    def test_attributes(self):
        self.assert_(isinstance(sys.api_version, int))
        self.assert_(isinstance(sys.argv, list))
        self.assert_(sys.byteorder in ("little", "big"))
        self.assert_(isinstance(sys.builtin_module_names, tuple))
        self.assert_(isinstance(sys.copyright, basestring))
        self.assert_(isinstance(sys.exec_prefix, basestring))
        self.assert_(isinstance(sys.executable, basestring))
        self.assertEqual(len(sys.float_info), 11)
        self.assertEqual(sys.float_info.radix, 2)
        self.assert_(isinstance(sys.hexversion, int))
        self.assert_(isinstance(sys.maxint, int))
        if test.test_support.have_unicode:
            self.assert_(isinstance(sys.maxunicode, int))
        self.assert_(isinstance(sys.platform, basestring))
        self.assert_(isinstance(sys.prefix, basestring))
        self.assert_(isinstance(sys.version, basestring))
        vi = sys.version_info
        self.assert_(isinstance(vi, tuple))
        self.assertEqual(len(vi), 5)
        self.assert_(isinstance(vi[0], int))
        self.assert_(isinstance(vi[1], int))
        self.assert_(isinstance(vi[2], int))
        self.assert_(vi[3] in ("alpha", "beta", "candidate", "final"))
        self.assert_(isinstance(vi[4], int))

    def test_43581(self):
        # Can't use sys.stdout, as this is a cStringIO object when
        # the test runs under regrtest.
        self.assert_(sys.__stdout__.encoding == sys.__stderr__.encoding)

    def test_sys_flags(self):
        self.failUnless(sys.flags)
        attrs = ("debug", "py3k_warning", "division_warning", "division_new",
                 "inspect", "interactive", "optimize", "dont_write_bytecode",
                 "no_site", "ignore_environment", "tabcheck", "verbose",
                 "unicode", "bytes_warning")
        for attr in attrs:
            self.assert_(hasattr(sys.flags, attr), attr)
            self.assertEqual(type(getattr(sys.flags, attr)), int, attr)
        self.assert_(repr(sys.flags))

    def test_clear_type_cache(self):
        sys._clear_type_cache()

    def test_compact_freelists(self):
        sys._compact_freelists()
        r = sys._compact_freelists()
##        # freed blocks shouldn't change
##        self.assertEqual(r[0][2], 0)
##        self.assertEqual(r[1][2], 0)
##        # fill freelists
##        ints = list(range(10000))
##        floats = [float(i) for i in ints]
##        del ints
##        del floats
##        # should free more than 200 blocks each
##        r = sys._compact_freelists()
##        self.assert_(r[0][1] > 100, r[0][1])
##        self.assert_(r[1][2] > 100, r[1][1])
##
##        self.assert_(r[0][2] > 100, r[0][2])
##        self.assert_(r[1][2] > 100, r[1][2])

    def test_ioencoding(self):
        import subprocess,os
        env = dict(os.environ)

        # Test character: cent sign, encoded as 0x4A (ASCII J) in CP424,
        # not representable in ASCII.

        env["PYTHONIOENCODING"] = "cp424"
        p = subprocess.Popen([sys.executable, "-c", 'print unichr(0xa2)'],
                             stdout = subprocess.PIPE, env=env)
        out = p.stdout.read().strip()
        self.assertEqual(out, unichr(0xa2).encode("cp424"))

        env["PYTHONIOENCODING"] = "ascii:replace"
        p = subprocess.Popen([sys.executable, "-c", 'print unichr(0xa2)'],
                             stdout = subprocess.PIPE, env=env)
        out = p.stdout.read().strip()
        self.assertEqual(out, '?')


class SizeofTest(unittest.TestCase):

    def setUp(self):
        self.c = len(struct.pack('c', ' '))
        self.H = len(struct.pack('H', 0))
        self.i = len(struct.pack('i', 0))
        self.l = len(struct.pack('l', 0))
        self.P = len(struct.pack('P', 0))
        # due to missing size_t information from struct, it is assumed that
        # sizeof(Py_ssize_t) = sizeof(void*)
        self.header = 'PP'
        if hasattr(sys, "gettotalrefcount"):
            self.header += '2P'
        self.file = open(test.test_support.TESTFN, 'wb')

    def tearDown(self):
        self.file.close()
        test.test_support.unlink(test.test_support.TESTFN)

    def check_sizeof(self, o, size, size2=None):
        """Check size of o. Possible are size and optionally size2)."""
        result = sys.getsizeof(o)
        msg = 'wrong size for %s: got %d, expected ' % (type(o), result)
        if (size2 != None) and (result != size):
            self.assertEqual(result, size2, msg + str(size2))
        else:
            self.assertEqual(result, size, msg + str(size))

    def calcsize(self, fmt):
        """Wrapper around struct.calcsize which enforces the alignment of the
        end of a structure to the alignment requirement of pointer.

        Note: This wrapper should only be used if a pointer member is included
        and no member with a size larger than a pointer exists.
        """
        return struct.calcsize(fmt + '0P')

    def test_standardtypes(self):
        h = self.header
        size = self.calcsize
        # bool
        self.check_sizeof(True, size(h + 'l'))
        # buffer
        self.check_sizeof(buffer(''), size(h + '2P2Pil'))
        # cell
        def get_cell():
            x = 42
            def inner():
                return x
            return inner
        self.check_sizeof(get_cell().func_closure[0], size(h + 'P'))
        # old-style class
        class class_oldstyle():
            def method():
                pass
        self.check_sizeof(class_oldstyle, size(h + '6P'))
        # instance
        self.check_sizeof(class_oldstyle(), size(h + '3P'))
        # method
        self.check_sizeof(class_oldstyle().method, size(h + '4P'))
        # code
        self.check_sizeof(get_cell().func_code, size(h + '4i8Pi2P'))
        # complex
        self.check_sizeof(complex(0,1), size(h + '2d'))
        # enumerate
        self.check_sizeof(enumerate([]), size(h + 'l3P'))
        # reverse
        self.check_sizeof(reversed(''), size(h + 'PP'))
        # file
        self.check_sizeof(self.file, size(h + '4P2i4P3i3Pi'))
        # float
        self.check_sizeof(float(0), size(h + 'd'))
        # function
        def func(): pass
        self.check_sizeof(func, size(h + '9P'))
        class c():
            @staticmethod
            def foo():
                pass
            @classmethod
            def bar(cls):
                pass
            # staticmethod
            self.check_sizeof(foo, size(h + 'P'))
            # classmethod
            self.check_sizeof(bar, size(h + 'P'))
        # generator
        def get_gen(): yield 1
        self.check_sizeof(get_gen(), size(h + 'Pi2P'))
        # integer
        self.check_sizeof(1, size(h + 'l'))
        # builtin_function_or_method
        self.check_sizeof(abs, size(h + '3P'))
        # module
        self.check_sizeof(unittest, size(h + 'P'))
        # xrange
        self.check_sizeof(xrange(1), size(h + '3l'))
        # slice
        self.check_sizeof(slice(0), size(h + '3P'))

        h += 'P'
        # new-style class
        class class_newstyle(object):
            def method():
                pass
        # type (PyTypeObject + PyNumberMethods +  PyMappingMethods +
        #       PySequenceMethods + PyBufferProcs)
        self.check_sizeof(class_newstyle, size('P2P15Pl4PP9PP11PI') +\
                                          size(h + '41P 10P 3P 6P'))

    def test_specialtypes(self):
        h = self.header
        size = self.calcsize
        # dict
        self.check_sizeof({}, size(h + '3P2P') + 8*size('P2P'))
        longdict = {1:1, 2:2, 3:3, 4:4, 5:5, 6:6, 7:7, 8:8}
        self.check_sizeof(longdict, size(h + '3P2P') + (8+16)*size('P2P'))
        # unicode
        usize = len(u'\0'.encode('unicode-internal'))
        samples = [u'', u'1'*100]
        # we need to test for both sizes, because we don't know if the string
        # has been cached
        for s in samples:
            basicsize =  size(h + 'PPlP') + usize * (len(s) + 1)
            self.check_sizeof(s, basicsize,\
                                  size2=basicsize + sys.getsizeof(str(s)))
        # XXX trigger caching encoded version as Python string
        s = samples[1]
        try:
            getattr(sys, s)
        except AttributeError:
            pass
        finally:
            self.check_sizeof(s, basicsize + sys.getsizeof(str(s)))

        h += 'P'
        # list
        self.check_sizeof([], size(h + 'PP'))
        self.check_sizeof([1, 2, 3], size(h + 'PP') + 3*self.P)
        # long
        self.check_sizeof(0L, size(h + 'H'))
        self.check_sizeof(1L, size(h + 'H'))
        self.check_sizeof(-1L, size(h + 'H'))
        self.check_sizeof(32768L, size(h + 'H') + self.H)
        self.check_sizeof(32768L*32768L-1, size(h + 'H') + self.H)
        self.check_sizeof(32768L*32768L, size(h + 'H') + 2*self.H)
        # string
        self.check_sizeof('', size(h + 'lic'))
        self.check_sizeof('abc', size(h + 'lic') + 3*self.c)
        # tuple
        self.check_sizeof((), size(h))
        self.check_sizeof((1,2,3), size(h) + 3*self.P)


def test_main():
    test_classes = (SysModuleTest, SizeofTest)

    test.test_support.run_unittest(*test_classes)

if __name__ == "__main__":
    test_main()