OpenE2K
/
qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

qapi/introspect.py: create a typed 'Annotated' data strutcure 

Presently, we use a tuple to attach a dict containing annotations
(comments and compile-time conditionals) to a tree node. This is
undesirable because dicts are difficult to strongly type; promoting it
to a real class allows us to name the values and types of the
annotations we are expecting.

In terms of typing, the Annotated<T> type serves as a generic container
where the annotated node's type is preserved, allowing for greater
specificity than we'd be able to provide without a generic.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210216021809.134886-11-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This commit is contained in:
John Snow 2021-02-15 21:18:00 -05:00 committed by Markus Armbruster
parent 9db2734613
commit 4f7f97a7b3
1 changed files with 45 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

78
scripts/qapi/introspect.py
View File

@ -13,8 +13,12 @@ See the COPYING file in the top-level directory.
from typing import (
Any,
Dict,
Generic,
Iterable,
List,
Optional,
Tuple,
TypeVar,
Union,
)
@ -52,15 +56,25 @@ _Stub = Any
_Scalar = Union[str, bool, None]
_NonScalar = Union[Dict[str, _Stub], List[_Stub]]
_Value = Union[_Scalar, _NonScalar]
# JSONValue = TODO, in a forthcoming commit.
JSONValue = Union[_Value, 'Annotated[_Value]']
def _make_tree(obj, ifcond, comment=None):
extra = {
'if': ifcond,
'comment': comment
}
return (obj, extra)
_ValueT = TypeVar('_ValueT', bound=_Value)
class Annotated(Generic[_ValueT]):
"""
Annotated generally contains a SchemaInfo-like type (as a dict),
But it also used to wrap comments/ifconds around scalar leaf values,
for the benefit of features and enums.
"""
# TODO: Remove after Python 3.7 adds @dataclass:
# pylint: disable=too-few-public-methods
def __init__(self, value: _ValueT, ifcond: Iterable[str],
comment: Optional[str] = None):
self.value = value
self.comment: Optional[str] = comment
self.ifcond: Tuple[str, ...] = tuple(ifcond)
def _tree_to_qlit(obj, level=0, dict_value=False):
@ -68,11 +82,7 @@ def _tree_to_qlit(obj, level=0, dict_value=False):
def indent(level):
return level * 4 * ' '
if isinstance(obj, tuple):
ifobj, extra = obj
ifcond = extra.get('if')
comment = extra.get('comment')
if isinstance(obj, Annotated):
# NB: _tree_to_qlit is called recursively on the values of a
# key:value pair; those values can't be decorated with
# comments or conditionals.
@ -80,13 +90,13 @@ def _tree_to_qlit(obj, level=0, dict_value=False):
assert not dict_value, msg
ret = ''
if comment:
ret += indent(level) + '/* %s */\n' % comment
if ifcond:
ret += gen_if(ifcond)
ret += _tree_to_qlit(ifobj, level)
if ifcond:
ret += '\n' + gen_endif(ifcond)
if obj.comment:
ret += indent(level) + '/* %s */\n' % obj.comment
if obj.ifcond:
ret += gen_if(obj.ifcond)
ret += _tree_to_qlit(obj.value, level)
if obj.ifcond:
ret += '\n' + gen_endif(obj.ifcond)
return ret
ret = ''
@ -203,7 +213,7 @@ const QLitObject %(c_name)s = %(c_string)s;
@staticmethod
def _gen_features(features):
return [_make_tree(f.name, f.ifcond) for f in features]
return [Annotated(f.name, f.ifcond) for f in features]
def _gen_tree(self, name, mtype, obj, ifcond, features):
comment: Optional[str] = None
@ -217,7 +227,7 @@ const QLitObject %(c_name)s = %(c_string)s;
obj['meta-type'] = mtype
if features:
obj['features'] = self._gen_features(features)
self._trees.append(_make_tree(obj, ifcond, comment))
self._trees.append(Annotated(obj, ifcond, comment))
def _gen_member(self, member):
obj = {'name': member.name, 'type': self._use_type(member.type)}
@ -225,7 +235,7 @@ const QLitObject %(c_name)s = %(c_string)s;
obj['default'] = None
if member.features:
obj['features'] = self._gen_features(member.features)
return _make_tree(obj, member.ifcond)
return Annotated(obj, member.ifcond)
def _gen_variants(self, tag_name, variants):
return {'tag': tag_name,
@ -233,16 +243,17 @@ const QLitObject %(c_name)s = %(c_string)s;
def _gen_variant(self, variant):
obj = {'case': variant.name, 'type': self._use_type(variant.type)}
return _make_tree(obj, variant.ifcond)
return Annotated(obj, variant.ifcond)
def visit_builtin_type(self, name, info, json_type):
self._gen_tree(name, 'builtin', {'json-type': json_type}, [], None)
def visit_enum_type(self, name, info, ifcond, features, members, prefix):
self._gen_tree(name, 'enum',
{'values': [_make_tree(m.name, m.ifcond, None)
for m in members]},
ifcond, features)
self._gen_tree(
name, 'enum',
{'values': [Annotated(m.name, m.ifcond) for m in members]},
ifcond, features
)
def visit_array_type(self, name, info, ifcond, element_type):
element = self._use_type(element_type)
@ -259,12 +270,13 @@ const QLitObject %(c_name)s = %(c_string)s;
self._gen_tree(name, 'object', obj, ifcond, features)
def visit_alternate_type(self, name, info, ifcond, features, variants):
self._gen_tree(name, 'alternate',
{'members': [
_make_tree({'type': self._use_type(m.type)},
m.ifcond, None)
for m in variants.variants]},
ifcond, features)
self._gen_tree(
name, 'alternate',
{'members': [Annotated({'type': self._use_type(m.type)},
m.ifcond)
for m in variants.variants]},
ifcond, features
)
def visit_command(self, name, info, ifcond, features,
arg_type, ret_type, gen, success_response, boxed,