John Snow <js...@redhat.com> writes: > This patch creates a new type, QAPIExpression, which represents a parsed > expression complete with QAPIDoc and QAPISourceInfo. > > This patch turns parser.exprs into a list of QAPIExpression instead, > and adjusts expr.py to match. > > This allows the types we specify in parser.py to be "remembered" all the > way through expr.py and into schema.py. Several assertions around > packing and unpacking this data can be removed as a result. > > NB: This necessitates a change of typing for check_if() and > check_keys(), because mypy does not believe UserDict[str, object] ⊆ > Dict[str, object]. It will, however, accept Mapping or > MutableMapping. In this case, the immutable form is preferred as an > input parameter because we don't actually mutate the input. > > Without this change, we will observe: > qapi/expr.py:631: error: Argument 1 to "check_keys" has incompatible > type "QAPIExpression"; expected "Dict[str, object]" > > NB2: Python 3.6 has an oversight for typing UserDict that makes it > impossible to type for both runtime and analysis time. The problem is > described in detail at https://github.com/python/typing/issues/60 - this > workaround can be safely removed when 3.7 is our minimum version. > > Signed-off-by: John Snow <js...@redhat.com> > ---
Looks good to me, just one question: [...] > diff --git a/scripts/qapi/parser.py b/scripts/qapi/parser.py > index 1b006cdc133..87b46db7fba 100644 > --- a/scripts/qapi/parser.py > +++ b/scripts/qapi/parser.py > @@ -14,13 +14,14 @@ > # This work is licensed under the terms of the GNU GPL, version 2. > # See the COPYING file in the top-level directory. > > -from collections import OrderedDict > +from collections import OrderedDict, UserDict > import os > import re > from typing import ( > TYPE_CHECKING, > Dict, > List, > + Mapping, > Optional, > Set, > Union, > @@ -37,15 +38,30 @@ > from .schema import QAPISchemaFeature, QAPISchemaMember > > > -#: Represents a single Top Level QAPI schema expression. > -TopLevelExpr = Dict[str, object] > - > # Return value alias for get_expr(). > _ExprValue = Union[List[object], Dict[str, object], str, bool] > > -# FIXME: Consolidate and centralize definitions for TopLevelExpr, > -# _ExprValue, _JSONValue, and _JSONObject; currently scattered across > -# several modules. > + > +# FIXME: Consolidate and centralize definitions for _ExprValue, > +# JSONValue, and _JSONObject; currently scattered across several > +# modules. > + > + > +# 3.6 workaround: can be removed when Python 3.7+ is our required version. > +if TYPE_CHECKING: > + _UserDict = UserDict[str, object] > +else: > + _UserDict = UserDict > + > + > +class QAPIExpression(_UserDict): Can we subclass dict instead? > + def __init__(self, > + initialdata: Mapping[str, object], > + info: QAPISourceInfo, > + doc: Optional['QAPIDoc'] = None): > + super().__init__(initialdata) > + self.info = info > + self.doc: Optional['QAPIDoc'] = doc > > > class QAPIParseError(QAPISourceError): [...]
