Merge flask framework and other stuff from master

1 files changed, 311 insertions, 0 deletions

diff --git a/python/click/decorators.py b/python/click/decorators.py
new file mode 100644
index 0000000..c57c530
--- /dev/null
+++ b/python/click/decorators.py
@@ -0,0 +1,311 @@
+import sys
+import inspect
+
+from functools import update_wrapper
+
+from ._compat import iteritems
+from ._unicodefun import _check_for_unicode_literals
+from .utils import echo
+from .globals import get_current_context
+
+
+def pass_context(f):
+    """Marks a callback as wanting to receive the current context
+    object as first argument.
+    """
+    def new_func(*args, **kwargs):
+        return f(get_current_context(), *args, **kwargs)
+    return update_wrapper(new_func, f)
+
+
+def pass_obj(f):
+    """Similar to :func:`pass_context`, but only pass the object on the
+    context onwards (:attr:`Context.obj`).  This is useful if that object
+    represents the state of a nested system.
+    """
+    def new_func(*args, **kwargs):
+        return f(get_current_context().obj, *args, **kwargs)
+    return update_wrapper(new_func, f)
+
+
+def make_pass_decorator(object_type, ensure=False):
+    """Given an object type this creates a decorator that will work
+    similar to :func:`pass_obj` but instead of passing the object of the
+    current context, it will find the innermost context of type
+    :func:`object_type`.
+
+    This generates a decorator that works roughly like this::
+
+        from functools import update_wrapper
+
+        def decorator(f):
+            @pass_context
+            def new_func(ctx, *args, **kwargs):
+                obj = ctx.find_object(object_type)
+                return ctx.invoke(f, obj, *args, **kwargs)
+            return update_wrapper(new_func, f)
+        return decorator
+
+    :param object_type: the type of the object to pass.
+    :param ensure: if set to `True`, a new object will be created and
+                   remembered on the context if it's not there yet.
+    """
+    def decorator(f):
+        def new_func(*args, **kwargs):
+            ctx = get_current_context()
+            if ensure:
+                obj = ctx.ensure_object(object_type)
+            else:
+                obj = ctx.find_object(object_type)
+            if obj is None:
+                raise RuntimeError('Managed to invoke callback without a '
+                                   'context object of type %r existing'
+                                   % object_type.__name__)
+            return ctx.invoke(f, obj, *args, **kwargs)
+        return update_wrapper(new_func, f)
+    return decorator
+
+
+def _make_command(f, name, attrs, cls):
+    if isinstance(f, Command):
+        raise TypeError('Attempted to convert a callback into a '
+                        'command twice.')
+    try:
+        params = f.__click_params__
+        params.reverse()
+        del f.__click_params__
+    except AttributeError:
+        params = []
+    help = attrs.get('help')
+    if help is None:
+        help = inspect.getdoc(f)
+        if isinstance(help, bytes):
+            help = help.decode('utf-8')
+    else:
+        help = inspect.cleandoc(help)
+    attrs['help'] = help
+    _check_for_unicode_literals()
+    return cls(name=name or f.__name__.lower().replace('_', '-'),
+               callback=f, params=params, **attrs)
+
+
+def command(name=None, cls=None, **attrs):
+    r"""Creates a new :class:`Command` and uses the decorated function as
+    callback.  This will also automatically attach all decorated
+    :func:`option`\s and :func:`argument`\s as parameters to the command.
+
+    The name of the command defaults to the name of the function.  If you
+    want to change that, you can pass the intended name as the first
+    argument.
+
+    All keyword arguments are forwarded to the underlying command class.
+
+    Once decorated the function turns into a :class:`Command` instance
+    that can be invoked as a command line utility or be attached to a
+    command :class:`Group`.
+
+    :param name: the name of the command.  This defaults to the function
+                 name with underscores replaced by dashes.
+    :param cls: the command class to instantiate.  This defaults to
+                :class:`Command`.
+    """
+    if cls is None:
+        cls = Command
+    def decorator(f):
+        cmd = _make_command(f, name, attrs, cls)
+        cmd.__doc__ = f.__doc__
+        return cmd
+    return decorator
+
+
+def group(name=None, **attrs):
+    """Creates a new :class:`Group` with a function as callback.  This
+    works otherwise the same as :func:`command` just that the `cls`
+    parameter is set to :class:`Group`.
+    """
+    attrs.setdefault('cls', Group)
+    return command(name, **attrs)
+
+
+def _param_memo(f, param):
+    if isinstance(f, Command):
+        f.params.append(param)
+    else:
+        if not hasattr(f, '__click_params__'):
+            f.__click_params__ = []
+        f.__click_params__.append(param)
+
+
+def argument(*param_decls, **attrs):
+    """Attaches an argument to the command.  All positional arguments are
+    passed as parameter declarations to :class:`Argument`; all keyword
+    arguments are forwarded unchanged (except ``cls``).
+    This is equivalent to creating an :class:`Argument` instance manually
+    and attaching it to the :attr:`Command.params` list.
+
+    :param cls: the argument class to instantiate.  This defaults to
+                :class:`Argument`.
+    """
+    def decorator(f):
+        ArgumentClass = attrs.pop('cls', Argument)
+        _param_memo(f, ArgumentClass(param_decls, **attrs))
+        return f
+    return decorator
+
+
+def option(*param_decls, **attrs):
+    """Attaches an option to the command.  All positional arguments are
+    passed as parameter declarations to :class:`Option`; all keyword
+    arguments are forwarded unchanged (except ``cls``).
+    This is equivalent to creating an :class:`Option` instance manually
+    and attaching it to the :attr:`Command.params` list.
+
+    :param cls: the option class to instantiate.  This defaults to
+                :class:`Option`.
+    """
+    def decorator(f):
+        # Issue 926, copy attrs, so pre-defined options can re-use the same cls=
+        option_attrs = attrs.copy()
+
+        if 'help' in option_attrs:
+            option_attrs['help'] = inspect.cleandoc(option_attrs['help'])
+        OptionClass = option_attrs.pop('cls', Option)
+        _param_memo(f, OptionClass(param_decls, **option_attrs))
+        return f
+    return decorator
+
+
+def confirmation_option(*param_decls, **attrs):
+    """Shortcut for confirmation prompts that can be ignored by passing
+    ``--yes`` as parameter.
+
+    This is equivalent to decorating a function with :func:`option` with
+    the following parameters::
+
+        def callback(ctx, param, value):
+            if not value:
+                ctx.abort()
+
+        @click.command()
+        @click.option('--yes', is_flag=True, callback=callback,
+                      expose_value=False, prompt='Do you want to continue?')
+        def dropdb():
+            pass
+    """
+    def decorator(f):
+        def callback(ctx, param, value):
+            if not value:
+                ctx.abort()
+        attrs.setdefault('is_flag', True)
+        attrs.setdefault('callback', callback)
+        attrs.setdefault('expose_value', False)
+        attrs.setdefault('prompt', 'Do you want to continue?')
+        attrs.setdefault('help', 'Confirm the action without prompting.')
+        return option(*(param_decls or ('--yes',)), **attrs)(f)
+    return decorator
+
+
+def password_option(*param_decls, **attrs):
+    """Shortcut for password prompts.
+
+    This is equivalent to decorating a function with :func:`option` with
+    the following parameters::
+
+        @click.command()
+        @click.option('--password', prompt=True, confirmation_prompt=True,
+                      hide_input=True)
+        def changeadmin(password):
+            pass
+    """
+    def decorator(f):
+        attrs.setdefault('prompt', True)
+        attrs.setdefault('confirmation_prompt', True)
+        attrs.setdefault('hide_input', True)
+        return option(*(param_decls or ('--password',)), **attrs)(f)
+    return decorator
+
+
+def version_option(version=None, *param_decls, **attrs):
+    """Adds a ``--version`` option which immediately ends the program
+    printing out the version number.  This is implemented as an eager
+    option that prints the version and exits the program in the callback.
+
+    :param version: the version number to show.  If not provided Click
+                    attempts an auto discovery via setuptools.
+    :param prog_name: the name of the program (defaults to autodetection)
+    :param message: custom message to show instead of the default
+                    (``'%(prog)s, version %(version)s'``)
+    :param others: everything else is forwarded to :func:`option`.
+    """
+    if version is None:
+        if hasattr(sys, '_getframe'):
+            module = sys._getframe(1).f_globals.get('__name__')
+        else:
+            module = ''
+
+    def decorator(f):
+        prog_name = attrs.pop('prog_name', None)
+        message = attrs.pop('message', '%(prog)s, version %(version)s')
+
+        def callback(ctx, param, value):
+            if not value or ctx.resilient_parsing:
+                return
+            prog = prog_name
+            if prog is None:
+                prog = ctx.find_root().info_name
+            ver = version
+            if ver is None:
+                try:
+                    import pkg_resources
+                except ImportError:
+                    pass
+                else:
+                    for dist in pkg_resources.working_set:
+                        scripts = dist.get_entry_map().get('console_scripts') or {}
+                        for script_name, entry_point in iteritems(scripts):
+                            if entry_point.module_name == module:
+                                ver = dist.version
+                                break
+                if ver is None:
+                    raise RuntimeError('Could not determine version')
+            echo(message % {
+                'prog': prog,
+                'version': ver,
+            }, color=ctx.color)
+            ctx.exit()
+
+        attrs.setdefault('is_flag', True)
+        attrs.setdefault('expose_value', False)
+        attrs.setdefault('is_eager', True)
+        attrs.setdefault('help', 'Show the version and exit.')
+        attrs['callback'] = callback
+        return option(*(param_decls or ('--version',)), **attrs)(f)
+    return decorator
+
+
+def help_option(*param_decls, **attrs):
+    """Adds a ``--help`` option which immediately ends the program
+    printing out the help page.  This is usually unnecessary to add as
+    this is added by default to all commands unless suppressed.
+
+    Like :func:`version_option`, this is implemented as eager option that
+    prints in the callback and exits.
+
+    All arguments are forwarded to :func:`option`.
+    """
+    def decorator(f):
+        def callback(ctx, param, value):
+            if value and not ctx.resilient_parsing:
+                echo(ctx.get_help(), color=ctx.color)
+                ctx.exit()
+        attrs.setdefault('is_flag', True)
+        attrs.setdefault('expose_value', False)
+        attrs.setdefault('help', 'Show this message and exit.')
+        attrs.setdefault('is_eager', True)
+        attrs['callback'] = callback
+        return option(*(param_decls or ('--help',)), **attrs)(f)
+    return decorator
+
+
+# Circular dependencies between core and decorators
+from .core import Command, Group, Argument, Option