python类install_hooks()的实例源码

def install_hooks():
    """
    This function installs the future.standard_library import hook into
    sys.meta_path.
    """
    if PY3:
        return

    install_aliases()

    flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
    flog.debug('Installing hooks ...')

    # Add it unless it's there already
    newhook = RenameImport(RENAMES)
    if not detect_hooks():
        sys.meta_path.append(newhook)
    flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))

def detect_hooks():
    """
    Returns True if the import hooks are installed, False if not.
    """
    flog.debug('Detecting hooks ...')
    present = any([hasattr(hook, 'RENAMER') for hook in sys.meta_path])
    if present:
        flog.debug('Detected.')
    else:
        flog.debug('Not detected.')
    return present


# As of v0.12, this no longer happens implicitly:
# if not PY3:
#     install_hooks()

def test_remove_hooks_then_requests(self):
        code = """
            from future import standard_library
            standard_library.install_hooks()

            import builtins
            import http.client
            import html.parser
            """
        with write_module(code, self.tempdir):
            import test_imports_future_stdlib
            standard_library.remove_hooks()
            try:
                import requests
            except ImportError:
                print("Requests doesn't seem to be available. Skipping requests test ...")
            else:
                r = requests.get('http://google.com')
                self.assertTrue(r)
            self.assertTrue(True)

def test_import_failure_from_module(self):
        """
        Tests whether e.g. "import socketserver" succeeds in a module
        imported by another module that has used and removed the stdlib hooks.
        We want this to fail; the stdlib hooks should not bleed to imported
        modules too without their explicitly invoking them.
        """
        code1 = '''
                from future import standard_library
                standard_library.install_hooks()
                standard_library.remove_hooks()
                import importme2
                '''
        code2 = '''
                import socketserver
                print('Uh oh. importme2 should have raised an ImportError.')
                '''
        self._write_test_script(code1, 'importme1.py')
        self._write_test_script(code2, 'importme2.py')
        with self.assertRaises(CalledProcessError):
            output = self._run_test_script('importme1.py')

def detect_hooks():
    """
    Returns True if the import hooks are installed, False if not.
    """
    flog.debug('Detecting hooks ...')
    present = any([hasattr(hook, 'RENAMER') for hook in sys.meta_path])
    if present:
        flog.debug('Detected.')
    else:
        flog.debug('Not detected.')
    return present


# As of v0.12, this no longer happens implicitly:
# if not PY3:
#     install_hooks()

def install_hooks():
    """
    This function installs the future.standard_library import hook into
    sys.meta_path.
    """
    if PY3:
        return

    install_aliases()

    flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
    flog.debug('Installing hooks ...')

    # Add it unless it's there already
    newhook = RenameImport(RENAMES)
    if not detect_hooks():
        sys.meta_path.append(newhook)
    flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))

def install_hooks():
    """
    This function installs the future.standard_library import hook into
    sys.meta_path.
    """
    if PY3:
        return

    install_aliases()

    flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
    flog.debug('Installing hooks ...')

    # Add it unless it's there already
    newhook = RenameImport(RENAMES)
    if not detect_hooks():
        sys.meta_path.append(newhook)
    flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))

def install_hooks():
    """
    This function installs the future.standard_library import hook into
    sys.meta_path.
    """
    if PY3:
        return

    install_aliases()

    flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
    flog.debug('Installing hooks ...')

    # Add it unless it's there already
    newhook = RenameImport(RENAMES)
    if not detect_hooks():
        sys.meta_path.append(newhook)
    flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))

def install_hooks():
    """
    This function installs the future.standard_library import hook into
    sys.meta_path.
    """
    if PY3:
        return

    install_aliases()

    flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
    flog.debug('Installing hooks ...')

    # Add it unless it's there already
    newhook = RenameImport(RENAMES)
    if not detect_hooks():
        sys.meta_path.append(newhook)
    flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))

def install_hooks():
    """
    This function installs the future.standard_library import hook into
    sys.meta_path.
    """
    if PY3:
        return

    install_aliases()

    flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
    flog.debug('Installing hooks ...')

    # Add it unless it's there already
    newhook = RenameImport(RENAMES)
    if not detect_hooks():
        sys.meta_path.append(newhook)
    flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))

def install_hooks():
    """
    This function installs the future.standard_library import hook into
    sys.meta_path.
    """
    if PY3:
        return

    install_aliases()

    flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
    flog.debug('Installing hooks ...')

    # Add it unless it's there already
    newhook = RenameImport(RENAMES)
    if not detect_hooks():
        sys.meta_path.append(newhook)
    flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))

def install_hooks():
    """
    This function installs the future.standard_library import hook into
    sys.meta_path.
    """
    if PY3:
        return

    install_aliases()

    flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
    flog.debug('Installing hooks ...')

    # Add it unless it's there already
    newhook = RenameImport(RENAMES)
    if not detect_hooks():
        sys.meta_path.append(newhook)
    flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))

def install_hooks():
    """
    This function installs the future.standard_library import hook into
    sys.meta_path.
    """
    if PY3:
        return

    install_aliases()

    flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
    flog.debug('Installing hooks ...')

    # Add it unless it's there already
    newhook = RenameImport(RENAMES)
    if not detect_hooks():
        sys.meta_path.append(newhook)
    flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))

def install_hooks():
    """
    This function installs the future.standard_library import hook into
    sys.meta_path.
    """
    if PY3:
        return

    install_aliases()

    flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
    flog.debug('Installing hooks ...')

    # Add it unless it's there already
    newhook = RenameImport(RENAMES)
    if not detect_hooks():
        sys.meta_path.append(newhook)
    flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))

def __enter__(self):
        # flog.debug('Entering hooks context manager')
        self.old_sys_modules = copy.copy(sys.modules)
        self.hooks_were_installed = detect_hooks()
        # self.scrubbed = scrub_py2_sys_modules()
        install_hooks()
        return self

def __exit__(self, *args):
        if self.hooks_were_installed:
            install_hooks()
        # restore_sys_modules(self.scrubbed)

def enable_hooks():
    """
    Deprecated. Use install_hooks() instead. This will be removed by
    ``future`` v1.0.
    """
    install_hooks()

def test_disable_hooks(self):
        """
        Tests the old (deprecated) names. These deprecated aliases should be
        removed by version 1.0
        """
        example_PY2_check = False

        standard_library.enable_hooks()   # deprecated name
        old_meta_path = copy.copy(sys.meta_path)

        standard_library.disable_hooks()
        standard_library.scrub_future_sys_modules()
        if utils.PY2:
            self.assertTrue(len(old_meta_path) == len(sys.meta_path) + 1)
        else:
            self.assertTrue(len(old_meta_path) == len(sys.meta_path))

        # An example of fragile import code that we don't want to break:
        try:
            import builtins
        except ImportError:
            example_PY2_check = True
        if utils.PY2:
            self.assertTrue(example_PY2_check)
        else:
            self.assertFalse(example_PY2_check)

        standard_library.install_hooks()

        # Imports should succeed again now:
        import builtins
        import configparser
        if utils.PY2:
            self.assertTrue(standard_library.detect_hooks())
            self.assertTrue(len(old_meta_path) == len(sys.meta_path))

def test_remove_hooks2(self):
        """
        As above, but with the new names
        """
        example_PY2_check = False

        standard_library.install_hooks()
        old_meta_path = copy.copy(sys.meta_path)

        standard_library.remove_hooks()
        standard_library.scrub_future_sys_modules()
        if utils.PY2:
            self.assertTrue(len(old_meta_path) == len(sys.meta_path) + 1)
        else:
            self.assertTrue(len(old_meta_path) == len(sys.meta_path))

        # An example of fragile import code that we don't want to break:
        try:
            import builtins
        except ImportError:
            example_PY2_check = True
        if utils.PY2:
            self.assertTrue(example_PY2_check)
        else:
            self.assertFalse(example_PY2_check)
        standard_library.install_hooks()
        # The import should succeed again now:
        import builtins
        self.assertTrue(len(old_meta_path) == len(sys.meta_path))

def test_detect_hooks(self):
        """
        Tests whether the future.standard_library.detect_hooks is doing
        its job.
        """
        standard_library.install_hooks()
        if utils.PY2:
            self.assertTrue(standard_library.detect_hooks())

        meta_path = copy.copy(sys.meta_path)

        standard_library.remove_hooks()
        if utils.PY2:
            self.assertEqual(len(meta_path), len(sys.meta_path) + 1)
            self.assertFalse(standard_library.detect_hooks())

def write_and_import(self, code, modulename='mymodule'):
        self.assertTrue('.py' not in modulename)
        filename = modulename + '.py'
        if isinstance(code, bytes):
            code = code.decode('utf-8')
        # Be explicit about encoding the temp file as UTF-8 (issue #63):
        with io.open(self.tempdir + filename, 'w', encoding='utf-8') as f:
            f.write(textwrap.dedent(code).strip() + '\n')

        # meta_path_len = len(sys.meta_path)
        install_hooks(modulename)
        # print('Hooks installed')
        # assert len(sys.meta_path) == 1 + meta_path_len
        # print('sys.meta_path is: {0}'.format(sys.meta_path))
        module = None

        sys.path.insert(0, self.tempdir)
        try:
            module = __import__(modulename)
        except SyntaxError:
            print('Bombed!')
        else:
            print('Succeeded!')
        finally:
            remove_hooks()
            # print('Hooks removed')
            sys.path.remove(self.tempdir)
        return module

def test_import_future_standard_library(self):
        """
        Does futurized Py3-like code like this work under autotranslation??
        """
        code = """
        from future import standard_library
        standard_library.install_hooks()
        import configparser
        """
        module = self.write_and_import(code, 'future_standard_library')
        self.assertTrue('configparser' in dir(module))
        from future import standard_library
        standard_library.remove_hooks()

def transform(self, node, results):
        # TODO: add a blank line between any __future__ imports and this?
        touch_import_top(u'future', u'standard_library', node)
        # TODO: also add standard_library.install_hooks()

def __enter__(self):
        # flog.debug('Entering hooks context manager')
        self.old_sys_modules = copy.copy(sys.modules)
        self.hooks_were_installed = detect_hooks()
        # self.scrubbed = scrub_py2_sys_modules()
        install_hooks()
        return self

def __exit__(self, *args):
        if self.hooks_were_installed:
            install_hooks()
        # restore_sys_modules(self.scrubbed)

def enable_hooks():
    """
    Deprecated. Use install_hooks() instead. This will be removed by
    ``future`` v1.0.
    """
    install_hooks()

def transform(self, node, results):
        # TODO: add a blank line between any __future__ imports and this?
        touch_import_top(u'future', u'standard_library', node)
        # TODO: also add standard_library.install_hooks()

def __enter__(self):
        # flog.debug('Entering hooks context manager')
        self.old_sys_modules = copy.copy(sys.modules)
        self.hooks_were_installed = detect_hooks()
        # self.scrubbed = scrub_py2_sys_modules()
        install_hooks()
        return self

def __exit__(self, *args):
        if self.hooks_were_installed:
            install_hooks()
        # restore_sys_modules(self.scrubbed)

def enable_hooks():
    """
    Deprecated. Use install_hooks() instead. This will be removed by
    ``future`` v1.0.
    """
    install_hooks()