Source code for beartype._conf.confenum

#!/usr/bin/env python3
# --------------------( LICENSE                            )--------------------
# Copyright (c) 2014-2024 Beartype authors.
# See "LICENSE" for further details.

'''
Beartype **configuration enumerations** (i.e., public enumerations whose members
may be passed as initialization-time parameters to the
:meth:`beartype._conf.confcls.BeartypeConf.__init__` constructor to configure
:mod:`beartype` with optional runtime type-checking behaviours).

Most of the public attributes defined by this private submodule are explicitly
exported to external users in our top-level :mod:`beartype.__init__` submodule.
This private submodule is *not* intended for direct importation by downstream
callers.
'''

# ....................{ IMPORTS                            }....................
from enum import (
    Enum,
    IntEnum,
    auto as next_enum_member_value,
    unique as die_unless_enum_member_values_unique,
)

# ....................{ ENUMERATIONS                       }....................
@die_unless_enum_member_values_unique
class BeartypeDecorationPosition(Enum):
    '''
    Enumeration of all kinds of **import hook decorator positions** (i.e.,
    competing locations to which the :func:`beartype.beartype` decorator will be
    implicitly injected into existing chains of one or more decorators
    decorating classes and callables defined by modules imported under
    :mod:`beartype.claw` import hooks, each with concomitant tradeoffs with
    respect to decorator interoperability and quality assurance).

    Attributes
    ----------
    FIRST : EnumMemberType
        **First (i.e., bottom-most) decorator position**, configuring
        :mod:`beartype.claw` import hooks to inject the
        :func:`beartype.beartype` decorator as the first (i.e., bottom-most)
        decorator in relevant decorator chains.

        Note that this position is *not* the default (and thus need be
        explicitly passed anywhere). Why? Various hand-wavy reasons, the most
        compelling of which is that this position ignores standard decorators
        and **thus violates PEP standards.** Notably, this position ignores:

        * The :pep:`484`-compliant :func:`typing.no_type_check` decorator, which
          then erroneously instructs :func:`beartye.beartype` to type-check
          classes and callables that should *not* be type-checked.
        * The :pep:`557`-compliant :func:`dataclasses.dataclass` decorator,
          which then prevents :func:`beartye.beartype` from type-checking
          dataclasses.
        * Explicitly configured :func:`beartype.beartype` decorators (e.g.,
          ``@beartype(conf=BeartypeConf(...))``), which then instructs
          :func:`beartye.beartype` to type-check classes and callables under
          differing configurations.

        When this position is used, implicit :func:`beartype.beartype`
        decorators injected by :mod:`beartype.claw` import hooks assume
        precedence over *all* other decorators (including those listed above),
        with predictably catastrophic results. Since this is almost never what
        anyone wants, this is *not* the default: e.g.,

        .. code-block:: python

           # Registering this import hook...
           from beartype import beartype, BeartypeConf, BeartypeDecorationPosition
           from beartype.claw import beartype_this_package
           beartype_this_package(conf=BeartypeConf(
               claw_decoration_position_types=BeartypeDecorationPosition.FIRST))

           # ...transforms chains of class decorators like this...
           from dataclasses import dataclass
           @beartype(conf=BeartypeConf(is_debug=True))
           @dataclass
           class ClassyData(object):
               integral_datum: int

           # ...into chains of class decorators like this.
           from dataclasses import dataclass
           @beartype(conf=BeartypeConf(is_debug=True))  # <-- *IGNORED*
           @dataclass  # <-- *IGNORED* by the @beartype decorator injected below
           @beartype   # <-- @beartype now ignores all of the above decorators!!
           class ClassyData(object):
               integral_datum: int

        In the above example, the default :func:`beartype.beartype` decorator
        injected by the :func:`beartype.claw.beartype_this_package` silently
        fails to type-check the :func:`dataclasses.dataclass` decorator and then
        overwrites the ``@beartype(conf=BeartypeConf(is_debug=True))`` decorator
        manually configured by the author of that third-party package.
        Consequently, caveats apply to usage of this position:

        * This position should only be applied to codebases that avoid
          explicitly decorating classes and/or callables with standard
          decorators, including:

          * The :pep:`484`-compliant :func:`typing.no_type_check` decorator.
          * The :pep:`557`-compliant :func:`dataclasses.dataclass` decorator.
          * The :func:`beartype.beartype` decorator itself.

        * Equivalently, this position should only be applied to codebases that
          implicitly decorate *all* classes and callables with
          :mod:`beartype.claw` import hooks.
        * Equivalently, if a codebase explicitly decorates even a single class
          or callable with the :func:`typing.no_type_check`,
          :func:`dataclasses.dataclass`, or :func:`beartype.beartype`
          decorators, this position should *not* be used.
        * Consequently, this position should *not* be applied to other packages
          outside your direct control.
        * In particular, this position should *not* be applied to all packages
          with the :func:`beartype.claw.beartype_all` import hook: e.g.,

          .. code-block:: python

             # Never do this. Srsly. Never do this. Srsly! Read this and weep.
             from beartype import BeartypeConf, BeartypeDecorationPosition
             from beartype.claw import beartype_all
             beartype_all(conf=BeartypeConf(
                 claw_decoration_position_types=BeartypeDecorationPosition.FIRST))
    LAST : EnumMemberType
        **Last (i.e., top-most) decorator position**, configuring
        :mod:`beartype.claw` import hooks to inject the
        :func:`beartype.beartype` decorator as the last (i.e., top-most)
        decorator in relevant decorator chains.

        Note that this position is already the default (and thus need *not* be
        explicitly passed anywhere). Why? Various hand-wavy reasons, the most
        compelling of which is that this position respects explicitly configured
        :func:`beartype.beartype` decorations (e.g.,
        ``@beartype(conf=BeartypeConf(...))``). When this position is used,
        explicit :func:`beartype.beartype` decorations assume precedence over
        implicit :func:`beartype.beartype` decorations injected by
        :mod:`beartype.claw` import hooks. Since that is almost always what
        everyone wants, this is the default position: e.g.,

        .. code-block:: python

           # Registering this import hook...
           from beartype import beartype, BeartypeConf, BeartypeDecorationPosition
           from beartype.claw import beartype_this_package
           beartype_this_package(conf=BeartypeConf(
               claw_decoration_position_funcs=BeartypeDecorationPosition.LAST))

           # ...transforms chains of function decorators like this...
           from functools import cache
           @cache
           @beartype(conf=BeartypeConf(is_debug=True))
           def chad_func() -> int:
               return 42

           # ...into chains of function decorators like this.
           from functools import cache
           @beartype  # <-- @beartype decorates last rather than first! \\o/
           @cache
           @beartype(conf=BeartypeConf(is_debug=True))
           def chad_func() -> int:
               return 42

        In the above example, the default :func:`beartype.beartype` decorator
        injected by the :func:`beartype.claw.beartype_this_package` import hook
        is silently ignored in favour of the non-default
        ``@beartype(conf=BeartypeConf(is_debug=True))`` decorator manually
        configured by the author of that third-party package.
    '''

    FIRST = next_enum_member_value()
    LAST = next_enum_member_value()


[docs] @die_unless_enum_member_values_unique class BeartypeStrategy(Enum): ''' Enumeration of all kinds of **type-checking strategies** (i.e., competing procedures for type-checking objects passed to or returned from :func:`beartype.beartype`-decorated callables, each with concomitant tradeoffs with respect to runtime complexity and quality assurance). Strategies are intentionally named according to `conventional Big O notation <Big O_>`__ (e.g., :attr:`BeartypeStrategy.On` enables the ``O(n)`` strategy). Strategies are established per-decoration at the fine-grained level of callables decorated by the :func:`beartype.beartype` decorator by setting the :attr:`beartype.BeartypeConf.strategy` parameter of the :class:`beartype.BeartypeConf` object passed as the optional ``conf`` parameter to that decorator. Strategies enforce their corresponding runtime complexities (e.g., ``O(n)``) across *all* type-checks performed for callables enabling those strategies. For example, a callable configured by the :attr:`BeartypeStrategy.On` strategy will exhibit linear ``O(n)`` complexity as its overhead for type-checking each nesting level of each container passed to and returned from that callable. .. _Big O: https://en.wikipedia.org/wiki/Big_O_notation Attributes ---------- O0 : EnumMemberType **No-time strategy** (i.e, disabling type-checking for a decorated callable by reducing :func:`beartype.beartype` to the identity decorator for that callable). Although seemingly useless, this strategy enables users to selectively blacklist (prevent) callables from being type-checked by our as-yet-unimplemented import hook. When implemented, that hook will type-check all callables within a package or module *except* those callables explicitly decorated by this strategy. O1 : EnumMemberType **Constant-time strategy** (i.e., the default ``O(1)`` strategy, type-checking a single randomly selected item of each container). As the default, this strategy need *not* be explicitly enabled. Ologn : EnumMemberType **Logarithmic-time strategy** (i.e., the ``O(log n)`` strategy, type-checking a randomly selected number of items ``log(len(obj))`` of each container ``obj``). This strategy is **currently unimplemented.** (*To be implemented by a future beartype release.*) On : EnumMemberType **Linear-time strategy** (i.e., the ``O(n)`` strategy, type-checking *all* items of a container). This strategy is **currently unimplemented.** (*To be implemented by a future beartype release.*) ''' O0 = next_enum_member_value() O1 = next_enum_member_value() Ologn = next_enum_member_value() On = next_enum_member_value()
@die_unless_enum_member_values_unique class BeartypeViolationVerbosity(IntEnum): ''' Enumeration of all kinds of **violation verbosities** (i.e., positive integers in the inclusive range ``[1, 5]`` governing the verbosity of exception messages raised by type-checking wrappers generated by the :func:`beartype.beartype` decorator when either receiving parameters *or* returning values violating their annotated type hints). Verbosities transparently reduce to integers and can thus be used wherever integers are used (e.g., ``BeartypeViolationVerbosity.DEFAULT + 1`` is the next level of verbosity beyond that of the default). Verbosities are established per-decoration at the fine-grained level of callables decorated by the :func:`beartype.beartype` decorator by setting the :attr:`beartype.BeartypeConf.violation_verbosity` parameter of the :class:`beartype.BeartypeConf` object passed as the optional ``conf`` parameter to that decorator. Attributes ---------- MINIMAL : EnumMemberType **Minimal verbosity,** intended for end users potentially lacking core expertise in Python. DEFAULT : EnumMemberType **Default verbosity,** intended for a general developer audience assumed to be fluent in Python. MAXIMAL : EnumMemberType **Maximum verbosity,** extending the default verbosity with additional contextual metadata intended for debugging violations. This includes: * A machine-readable representation of the beartype configuration under which the current violation occurred. ''' MINIMAL = next_enum_member_value() DEFAULT = next_enum_member_value() MAXIMAL = next_enum_member_value()