Python test.support.import_module() Examples

def test_select_unbuffered(self):
        # Issue #11459: bufsize=0 should really set the pipes as
        # unbuffered (and therefore let select() work properly).
        select = support.import_module("select")
        p = subprocess.Popen([sys.executable, "-c",
                              'import sys;'
                              'sys.stdout.write("apple")'],
                             stdout=subprocess.PIPE,
                             bufsize=0)
        f = p.stdout
        self.addCleanup(f.close)
        try:
            self.assertEqual(f.read(4), b"appl")
            self.assertIn(f, select.select([f], [], [], 0.0)[0])
        finally:
            p.wait() 

def test_aswidecharstring(self):
        from _testcapi import unicode_aswidecharstring
        support.import_module('ctypes')
        from ctypes import c_wchar, sizeof

        wchar, size = unicode_aswidecharstring('abc')
        self.assertEqual(size, 3)
        self.assertEqual(wchar, 'abc\0')

        wchar, size = unicode_aswidecharstring('abc\0def')
        self.assertEqual(size, 7)
        self.assertEqual(wchar, 'abc\0def\0')

        nonbmp = chr(0x10ffff)
        if sizeof(c_wchar) == 2:
            nchar = 2
        else: # sizeof(c_wchar) == 4
            nchar = 1
        wchar, size = unicode_aswidecharstring(nonbmp)
        self.assertEqual(size, nchar)
        self.assertEqual(wchar, nonbmp + '\0')

    # Test PyUnicode_AsUCS4() 

def test_aswidecharstring(self):
        from _testcapi import unicode_aswidecharstring
        support.import_module('ctypes')
        from ctypes import c_wchar, sizeof

        wchar, size = unicode_aswidecharstring('abc')
        self.assertEqual(size, 3)
        self.assertEqual(wchar, 'abc\0')

        wchar, size = unicode_aswidecharstring('abc\0def')
        self.assertEqual(size, 7)
        self.assertEqual(wchar, 'abc\0def\0')

        nonbmp = chr(0x10ffff)
        if sizeof(c_wchar) == 2:
            nchar = 2
        else: # sizeof(c_wchar) == 4
            nchar = 1
        wchar, size = unicode_aswidecharstring(nonbmp)
        self.assertEqual(size, nchar)
        self.assertEqual(wchar, nonbmp + '\0') 

def test_aswidecharstring(self):
        from _testcapi import unicode_aswidecharstring
        support.import_module('ctypes')
        from ctypes import c_wchar, sizeof

        wchar, size = unicode_aswidecharstring('abc')
        self.assertEqual(size, 3)
        self.assertEqual(wchar, 'abc\0')

        wchar, size = unicode_aswidecharstring('abc\0def')
        self.assertEqual(size, 7)
        self.assertEqual(wchar, 'abc\0def\0')

        nonbmp = chr(0x10ffff)
        if sizeof(c_wchar) == 2:
            nchar = 2
        else: # sizeof(c_wchar) == 4
            nchar = 1
        wchar, size = unicode_aswidecharstring(nonbmp)
        self.assertEqual(size, nchar)
        self.assertEqual(wchar, nonbmp + '\0')

    # Test PyUnicode_AsUCS4() 

def test_select_unbuffered(self):
        # Issue #11459: bufsize=0 should really set the pipes as
        # unbuffered (and therefore let select() work properly).
        select = support.import_module("select")
        p = subprocess.Popen([sys.executable, "-c",
                              'import sys;'
                              'sys.stdout.write("apple")'],
                             stdout=subprocess.PIPE,
                             bufsize=0)
        f = p.stdout
        self.addCleanup(f.close)
        try:
            self.assertEqual(f.read(4), b"appl")
            self.assertIn(f, select.select([f], [], [], 0.0)[0])
        finally:
            p.wait() 

def collect_in_thread(period=0.0001):
    """
    Ensure GC collections happen in a different thread, at a high frequency.
    """
    threading = support.import_module('threading')
    please_stop = False

    def collect():
        while not please_stop:
            time.sleep(period)
            gc.collect()

    with support.disable_gc():
        t = threading.Thread(target=collect)
        t.start()
        try:
            yield
        finally:
            please_stop = True
            t.join() 

def test_select_unbuffered(self):
        # Issue #11459: bufsize=0 should really set the pipes as
        # unbuffered (and therefore let select() work properly).
        select = support.import_module("select")
        p = subprocess.Popen([sys.executable, "-c",
                              'import sys;'
                              'sys.stdout.write("apple")'],
                             stdout=subprocess.PIPE,
                             bufsize=0)
        f = p.stdout
        self.addCleanup(f.close)
        try:
            self.assertEqual(f.read(4), b"appl")
            self.assertIn(f, select.select([f], [], [], 0.0)[0])
        finally:
            p.wait() 

def test_multiprocessing_exceptions(self):
        module = support.import_module('multiprocessing.context')
        for name, exc in get_exceptions(module):
            with self.subTest(name):
                self.assertEqual(reverse_mapping('multiprocessing.context', name),
                                 ('multiprocessing', name))
                self.assertEqual(mapping('multiprocessing', name),
                                 ('multiprocessing.context', name)) 

def test_import_module(self):
        support.import_module("ftplib")
        self.assertRaises(unittest.SkipTest, support.import_module, "foo") 

def test_CleanImport(self):
        import importlib
        with support.CleanImport("asyncore"):
            importlib.import_module("asyncore") 

def test_expanduser(self):
        P = self.cls
        support.import_module('pwd')
        import pwd
        pwdent = pwd.getpwuid(os.getuid())
        username = pwdent.pw_name
        userhome = pwdent.pw_dir.rstrip('/') or '/'
        # find arbitrary different user (if exists)
        for pwdent in pwd.getpwall():
            othername = pwdent.pw_name
            otherhome = pwdent.pw_dir.rstrip('/')
            if othername != username and otherhome:
                break

        p1 = P('~/Documents')
        p2 = P('~' + username + '/Documents')
        p3 = P('~' + othername + '/Documents')
        p4 = P('../~' + username + '/Documents')
        p5 = P('/~' + username + '/Documents')
        p6 = P('')
        p7 = P('~fakeuser/Documents')

        with support.EnvironmentVarGuard() as env:
            env.pop('HOME', None)

            self.assertEqual(p1.expanduser(), P(userhome) / 'Documents')
            self.assertEqual(p2.expanduser(), P(userhome) / 'Documents')
            self.assertEqual(p3.expanduser(), P(otherhome) / 'Documents')
            self.assertEqual(p4.expanduser(), p4)
            self.assertEqual(p5.expanduser(), p5)
            self.assertEqual(p6.expanduser(), p6)
            self.assertRaises(RuntimeError, p7.expanduser)

            env['HOME'] = '/tmp'
            self.assertEqual(p1.expanduser(), P('/tmp/Documents'))
            self.assertEqual(p2.expanduser(), P(userhome) / 'Documents')
            self.assertEqual(p3.expanduser(), P(otherhome) / 'Documents')
            self.assertEqual(p4.expanduser(), p4)
            self.assertEqual(p5.expanduser(), p5)
            self.assertEqual(p6.expanduser(), p6)
            self.assertRaises(RuntimeError, p7.expanduser) 

def test_asyncio_1(self):
        # asyncio cannot be imported when Python is compiled without thread
        # support
        asyncio = support.import_module('asyncio')

        class MyException(Exception):
            pass

        buffer = []

        class CM:
            async def __aenter__(self):
                buffer.append(1)
                await asyncio.sleep(0.01)
                buffer.append(2)
                return self

            async def __aexit__(self, exc_type, exc_val, exc_tb):
                await asyncio.sleep(0.01)
                buffer.append(exc_type.__name__)

        async def f():
            async with CM() as c:
                await asyncio.sleep(0.01)
                raise MyException
            buffer.append('unreachable')

        loop = asyncio.new_event_loop()
        asyncio.set_event_loop(loop)
        try:
            loop.run_until_complete(f())
        except MyException:
            pass
        finally:
            loop.close()
            asyncio.set_event_loop(None)

        self.assertEqual(buffer, [1, 2, 'MyException']) 

def test_response_fileno(self):
        # Make sure fd returned by fileno is valid.
        threading = support.import_module("threading")

        serv = socket.socket(
            socket.AF_INET, socket.SOCK_STREAM, socket.IPPROTO_TCP)
        self.addCleanup(serv.close)
        serv.bind((HOST, 0))
        serv.listen()

        result = None
        def run_server():
            [conn, address] = serv.accept()
            with conn, conn.makefile("rb") as reader:
                # Read the request header until a blank line
                while True:
                    line = reader.readline()
                    if not line.rstrip(b"\r\n"):
                        break
                conn.sendall(b"HTTP/1.1 200 Connection established\r\n\r\n")
                nonlocal result
                result = reader.read()

        thread = threading.Thread(target=run_server)
        thread.start()
        conn = client.HTTPConnection(*serv.getsockname())
        conn.request("CONNECT", "dummy:1234")
        response = conn.getresponse()
        try:
            self.assertEqual(response.status, client.OK)
            s = socket.socket(fileno=response.fileno())
            try:
                s.sendall(b"proxied data\n")
            finally:
                s.detach()
        finally:
            response.close()
            conn.close()
            thread.join()
        self.assertEqual(result, b"proxied data\n") 

def test_coverage(coverdir):
    trace = support.import_module('trace')
    tracer = trace.Trace(ignoredirs=[sys.base_prefix, sys.base_exec_prefix,],
                         trace=0, count=1)
    tracer.run('test_main()')
    r = tracer.results()
    print('Writing coverage results...')
    r.write_results(show_missing=True, summary=True,
                    coverdir=coverdir) 

def test_CleanImport(self):
        import importlib
        with support.CleanImport("asyncore"):
            importlib.import_module("asyncore") 

def test_coverage(coverdir):
    trace = support.import_module('trace')
    tracer=trace.Trace(ignoredirs=[sys.base_prefix, sys.base_exec_prefix,],
                        trace=0, count=1)
    tracer.run('import importlib; importlib.reload(cmd); test_main()')
    r=tracer.results()
    print("Writing coverage results...")
    r.write_results(show_missing=True, summary=True, coverdir=coverdir) 

def test_import_module(self):
        support.import_module("ftplib")
        self.assertRaises(unittest.SkipTest, support.import_module, "foo") 

def test_CleanImport(self):
        import importlib
        with support.CleanImport("asyncore"):
            importlib.import_module("asyncore") 

def test_asyncio_1(self):
        # asyncio cannot be imported when Python is compiled without thread
        # support
        asyncio = support.import_module('asyncio')

        class MyException(Exception):
            pass

        buffer = []

        class CM:
            async def __aenter__(self):
                buffer.append(1)
                await asyncio.sleep(0.01)
                buffer.append(2)
                return self

            async def __aexit__(self, exc_type, exc_val, exc_tb):
                await asyncio.sleep(0.01)
                buffer.append(exc_type.__name__)

        async def f():
            async with CM() as c:
                await asyncio.sleep(0.01)
                raise MyException
            buffer.append('unreachable')

        loop = asyncio.new_event_loop()
        asyncio.set_event_loop(loop)
        try:
            loop.run_until_complete(f())
        except MyException:
            pass
        finally:
            loop.close()
            asyncio.set_event_loop(None)

        self.assertEqual(buffer, [1, 2, 'MyException']) 

def test_empty_namespace_package(self):
        pkg_name = 'doctest_empty_pkg'
        with tempfile.TemporaryDirectory() as parent_dir:
            pkg_dir = os.path.join(parent_dir, pkg_name)
            os.mkdir(pkg_dir)
            sys.path.append(parent_dir)
            try:
                mod = importlib.import_module(pkg_name)
            finally:
                support.forget(pkg_name)
                sys.path.pop()
            assert doctest.DocTestFinder().find(mod) == [] 

def test_coverage(coverdir):
    trace = support.import_module('trace')
    tracer = trace.Trace(ignoredirs=[sys.base_prefix, sys.base_exec_prefix,],
                         trace=0, count=1)
    tracer.run('test_main()')
    r = tracer.results()
    print('Writing coverage results...')
    r.write_results(show_missing=True, summary=True,
                    coverdir=coverdir) 

def test_expanduser_pwd(self):
        pwd = support.import_module('pwd')

        self.assertIsInstance(posixpath.expanduser("~/"), str)
        self.assertIsInstance(posixpath.expanduser(b"~/"), bytes)

        # if home directory == root directory, this test makes no sense
        if posixpath.expanduser("~") != '/':
            self.assertEqual(
                posixpath.expanduser("~") + "/",
                posixpath.expanduser("~/")
            )
            self.assertEqual(
                posixpath.expanduser(b"~") + b"/",
                posixpath.expanduser(b"~/")
            )
        self.assertIsInstance(posixpath.expanduser("~root/"), str)
        self.assertIsInstance(posixpath.expanduser("~foo/"), str)
        self.assertIsInstance(posixpath.expanduser(b"~root/"), bytes)
        self.assertIsInstance(posixpath.expanduser(b"~foo/"), bytes)

        with support.EnvironmentVarGuard() as env:
            # expanduser should fall back to using the password database
            del env['HOME']

            home = pwd.getpwuid(os.getuid()).pw_dir
            # $HOME can end with a trailing /, so strip it (see #17809)
            home = home.rstrip("/") or '/'
            self.assertEqual(posixpath.expanduser("~"), home)

            # bpo-10496: If the HOME environment variable is not set and the
            # user (current identifier or name in the path) doesn't exist in
            # the password database (pwd.getuid() or pwd.getpwnam() fail),
            # expanduser() must return the path unchanged.
            with mock.patch.object(pwd, 'getpwuid', side_effect=KeyError), \
                 mock.patch.object(pwd, 'getpwnam', side_effect=KeyError):
                for path in ('~', '~/.local', '~vstinner/'):
                    self.assertEqual(posixpath.expanduser(path), path) 

def test_issue13210(self):
        # invoking "continue" on a non-main thread triggered an exception
        # inside signal.signal

        # raises SkipTest if python was built without threads
        support.import_module('threading')

        with open(support.TESTFN, 'wb') as f:
            f.write(textwrap.dedent("""
                import threading
                import pdb

                def start_pdb():
                    pdb.Pdb().set_trace()
                    x = 1
                    y = 1

                t = threading.Thread(target=start_pdb)
                t.start()""").encode('ascii'))
        cmd = [sys.executable, '-u', support.TESTFN]
        proc = subprocess.Popen(cmd,
            stdout=subprocess.PIPE,
            stdin=subprocess.PIPE,
            stderr=subprocess.STDOUT,
            )
        self.addCleanup(proc.stdout.close)
        stdout, stderr = proc.communicate(b'cont\n')
        self.assertNotIn('Error', stdout.decode(),
                         "Got an error running test script under PDB") 

def test_import_module(self):
        support.import_module("ftplib")
        self.assertRaises(unittest.SkipTest, support.import_module, "foo") 

def test_finalize_runnning_thread(self):
        # Issue 1402: the PyGILState_Ensure / _Release functions may be called
        # very late on python exit: on deallocation of a running thread for
        # example.
        import_module("ctypes")

        rc, out, err = assert_python_failure("-c", """if 1:
            import ctypes, sys, time, _thread

            # This lock is used as a simple event variable.
            ready = _thread.allocate_lock()
            ready.acquire()

            # Module globals are cleared before __del__ is run
            # So we save the functions in class dict
            class C:
                ensure = ctypes.pythonapi.PyGILState_Ensure
                release = ctypes.pythonapi.PyGILState_Release
                def __del__(self):
                    state = self.ensure()
                    self.release(state)

            def waitingThread():
                x = C()
                ready.release()
                time.sleep(100)

            _thread.start_new_thread(waitingThread, ())
            ready.acquire()  # Be sure the other thread is waiting.
            sys.exit(42)
            """)
        self.assertEqual(rc, 42) 

def test_import_module(self):
        support.import_module("ftplib")
        self.assertRaises(unittest.SkipTest, support.import_module, "foo") 

def test_CleanImport(self):
        import importlib
        with support.CleanImport("asyncore"):
            importlib.import_module("asyncore") 

def test_expanduser(self):
        P = self.cls
        support.import_module('pwd')
        import pwd
        pwdent = pwd.getpwuid(os.getuid())
        username = pwdent.pw_name
        userhome = pwdent.pw_dir.rstrip('/')
        # find arbitrary different user (if exists)
        for pwdent in pwd.getpwall():
            othername = pwdent.pw_name
            otherhome = pwdent.pw_dir.rstrip('/')
            if othername != username and otherhome:
                break

        p1 = P('~/Documents')
        p2 = P('~' + username + '/Documents')
        p3 = P('~' + othername + '/Documents')
        p4 = P('../~' + username + '/Documents')
        p5 = P('/~' + username + '/Documents')
        p6 = P('')
        p7 = P('~fakeuser/Documents')

        with support.EnvironmentVarGuard() as env:
            env.pop('HOME', None)

            self.assertEqual(p1.expanduser(), P(userhome) / 'Documents')
            self.assertEqual(p2.expanduser(), P(userhome) / 'Documents')
            self.assertEqual(p3.expanduser(), P(otherhome) / 'Documents')
            self.assertEqual(p4.expanduser(), p4)
            self.assertEqual(p5.expanduser(), p5)
            self.assertEqual(p6.expanduser(), p6)
            self.assertRaises(RuntimeError, p7.expanduser)

            env['HOME'] = '/tmp'
            self.assertEqual(p1.expanduser(), P('/tmp/Documents'))
            self.assertEqual(p2.expanduser(), P(userhome) / 'Documents')
            self.assertEqual(p3.expanduser(), P(otherhome) / 'Documents')
            self.assertEqual(p4.expanduser(), p4)
            self.assertEqual(p5.expanduser(), p5)
            self.assertEqual(p6.expanduser(), p6)
            self.assertRaises(RuntimeError, p7.expanduser) 

def test_asyncio_1(self):
        # asyncio cannot be imported when Python is compiled without thread
        # support
        asyncio = support.import_module('asyncio')

        class MyException(Exception):
            pass

        buffer = []

        class CM:
            async def __aenter__(self):
                buffer.append(1)
                await asyncio.sleep(0.01)
                buffer.append(2)
                return self

            async def __aexit__(self, exc_type, exc_val, exc_tb):
                await asyncio.sleep(0.01)
                buffer.append(exc_type.__name__)

        async def f():
            async with CM() as c:
                await asyncio.sleep(0.01)
                raise MyException
            buffer.append('unreachable')

        loop = asyncio.new_event_loop()
        asyncio.set_event_loop(loop)
        try:
            loop.run_until_complete(f())
        except MyException:
            pass
        finally:
            loop.close()
            asyncio.set_event_loop(None)

        self.assertEqual(buffer, [1, 2, 'MyException']) 

def test_coverage(coverdir):
    trace = support.import_module('trace')
    tracer = trace.Trace(ignoredirs=[sys.base_prefix, sys.base_exec_prefix,],
                         trace=0, count=1)
    tracer.run('test_main()')
    r = tracer.results()
    print('Writing coverage results...')
    r.write_results(show_missing=True, summary=True,
                    coverdir=coverdir)