| # Copyright 2013-2021 The Meson development team |
| |
| # Licensed under the Apache License, Version 2.0 (the "License"); |
| # you may not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| from __future__ import annotations |
| |
| from .. import mparser |
| from .exceptions import InvalidCode, InvalidArguments |
| from .helpers import flatten, resolve_second_level_holders |
| from .operator import MesonOperator |
| from ..mesonlib import HoldableObject, MesonBugException |
| import textwrap |
| |
| import typing as T |
| from abc import ABCMeta |
| from contextlib import AbstractContextManager |
| |
| if T.TYPE_CHECKING: |
| from typing_extensions import Protocol |
| |
| # Object holders need the actual interpreter |
| from ..interpreter import Interpreter |
| |
| __T = T.TypeVar('__T', bound='TYPE_var', contravariant=True) |
| |
| class OperatorCall(Protocol[__T]): |
| def __call__(self, other: __T) -> 'TYPE_var': ... |
| |
| |
| TV_func = T.TypeVar('TV_func', bound=T.Callable[..., T.Any]) |
| |
| TYPE_elementary = T.Union[str, int, bool, T.List[T.Any], T.Dict[str, T.Any]] |
| TYPE_var = T.Union[TYPE_elementary, HoldableObject, 'MesonInterpreterObject'] |
| TYPE_nvar = T.Union[TYPE_var, mparser.BaseNode] |
| TYPE_kwargs = T.Dict[str, TYPE_var] |
| TYPE_nkwargs = T.Dict[str, TYPE_nvar] |
| TYPE_key_resolver = T.Callable[[mparser.BaseNode], str] |
| |
| SubProject = T.NewType('SubProject', str) |
| |
| class InterpreterObject: |
| def __init__(self, *, subproject: T.Optional['SubProject'] = None) -> None: |
| self.methods: T.Dict[ |
| str, |
| T.Callable[[T.List[TYPE_var], TYPE_kwargs], TYPE_var] |
| ] = {} |
| self.operators: T.Dict[MesonOperator, 'OperatorCall'] = {} |
| self.trivial_operators: T.Dict[ |
| MesonOperator, |
| T.Tuple[ |
| T.Union[T.Type, T.Tuple[T.Type, ...]], |
| 'OperatorCall' |
| ] |
| ] = {} |
| # Current node set during a method call. This can be used as location |
| # when printing a warning message during a method call. |
| self.current_node: mparser.BaseNode = None |
| self.subproject = subproject or SubProject('') |
| |
| # Some default operators supported by all objects |
| self.operators.update({ |
| MesonOperator.EQUALS: self.op_equals, |
| MesonOperator.NOT_EQUALS: self.op_not_equals, |
| }) |
| |
| # The type of the object that can be printed to the user |
| def display_name(self) -> str: |
| return type(self).__name__ |
| |
| def method_call( |
| self, |
| method_name: str, |
| args: T.List[TYPE_var], |
| kwargs: TYPE_kwargs |
| ) -> TYPE_var: |
| if method_name in self.methods: |
| method = self.methods[method_name] |
| if not getattr(method, 'no-args-flattening', False): |
| args = flatten(args) |
| if not getattr(method, 'no-second-level-holder-flattening', False): |
| args, kwargs = resolve_second_level_holders(args, kwargs) |
| return method(args, kwargs) |
| raise InvalidCode(f'Unknown method "{method_name}" in object {self} of type {type(self).__name__}.') |
| |
| def operator_call(self, operator: MesonOperator, other: TYPE_var) -> TYPE_var: |
| if operator in self.trivial_operators: |
| op = self.trivial_operators[operator] |
| if op[0] is None and other is not None: |
| raise MesonBugException(f'The unary operator `{operator.value}` of {self.display_name()} was passed the object {other} of type {type(other).__name__}') |
| if op[0] is not None and not isinstance(other, op[0]): |
| raise InvalidArguments(f'The `{operator.value}` operator of {self.display_name()} does not accept objects of type {type(other).__name__} ({other})') |
| return op[1](other) |
| if operator in self.operators: |
| return self.operators[operator](other) |
| raise InvalidCode(f'Object {self} of type {self.display_name()} does not support the `{operator.value}` operator.') |
| |
| # Default comparison operator support |
| def _throw_comp_exception(self, other: TYPE_var, opt_type: str) -> T.NoReturn: |
| raise InvalidArguments(textwrap.dedent( |
| f''' |
| Trying to compare values of different types ({self.display_name()}, {type(other).__name__}) using {opt_type}. |
| This was deprecated and undefined behavior previously and is as of 0.60.0 a hard error. |
| ''' |
| )) |
| |
| def op_equals(self, other: TYPE_var) -> bool: |
| # We use `type(...) == type(...)` here to enforce an *exact* match for comparison. We |
| # don't want comparisons to be possible where `isinstance(derived_obj, type(base_obj))` |
| # would pass because this comparison must never be true: `derived_obj == base_obj` |
| if type(self) is not type(other): |
| self._throw_comp_exception(other, '==') |
| return self == other |
| |
| def op_not_equals(self, other: TYPE_var) -> bool: |
| if type(self) is not type(other): |
| self._throw_comp_exception(other, '!=') |
| return self != other |
| |
| class MesonInterpreterObject(InterpreterObject): |
| ''' All non-elementary objects and non-object-holders should be derived from this ''' |
| |
| class MutableInterpreterObject: |
| ''' Dummy class to mark the object type as mutable ''' |
| |
| HoldableTypes = (HoldableObject, int, bool, str, list, dict) |
| TYPE_HoldableTypes = T.Union[TYPE_elementary, HoldableObject] |
| InterpreterObjectTypeVar = T.TypeVar('InterpreterObjectTypeVar', bound=TYPE_HoldableTypes) |
| |
| class ObjectHolder(InterpreterObject, T.Generic[InterpreterObjectTypeVar]): |
| def __init__(self, obj: InterpreterObjectTypeVar, interpreter: 'Interpreter') -> None: |
| super().__init__(subproject=interpreter.subproject) |
| # This causes some type checkers to assume that obj is a base |
| # HoldableObject, not the specialized type, so only do this assert in |
| # non-type checking situations |
| if not T.TYPE_CHECKING: |
| assert isinstance(obj, HoldableTypes), f'This is a bug: Trying to hold object of type `{type(obj).__name__}` that is not in `{HoldableTypes}`' |
| self.held_object = obj |
| self.interpreter = interpreter |
| self.env = self.interpreter.environment |
| |
| # Hide the object holder abstraction from the user |
| def display_name(self) -> str: |
| return type(self.held_object).__name__ |
| |
| # Override default comparison operators for the held object |
| def op_equals(self, other: TYPE_var) -> bool: |
| # See the comment from InterpreterObject why we are using `type()` here. |
| if type(self.held_object) is not type(other): |
| self._throw_comp_exception(other, '==') |
| return self.held_object == other |
| |
| def op_not_equals(self, other: TYPE_var) -> bool: |
| if type(self.held_object) is not type(other): |
| self._throw_comp_exception(other, '!=') |
| return self.held_object != other |
| |
| def __repr__(self) -> str: |
| return f'<[{type(self).__name__}] holds [{type(self.held_object).__name__}]: {self.held_object!r}>' |
| |
| class IterableObject(metaclass=ABCMeta): |
| '''Base class for all objects that can be iterated over in a foreach loop''' |
| |
| def iter_tuple_size(self) -> T.Optional[int]: |
| '''Return the size of the tuple for each iteration. Returns None if only a single value is returned.''' |
| raise MesonBugException(f'iter_tuple_size not implemented for {self.__class__.__name__}') |
| |
| def iter_self(self) -> T.Iterator[T.Union[TYPE_var, T.Tuple[TYPE_var, ...]]]: |
| raise MesonBugException(f'iter not implemented for {self.__class__.__name__}') |
| |
| def size(self) -> int: |
| raise MesonBugException(f'size not implemented for {self.__class__.__name__}') |
| |
| class ContextManagerObject(MesonInterpreterObject, AbstractContextManager): |
| def __init__(self, subproject: 'SubProject') -> None: |
| super().__init__(subproject=subproject) |
