Re: [PATCH v3 08/16] qapi/expr.py: add type hint annotations

[Markus Armbruster <armbru@redhat.com>]

John Snow <jsnow@redhat.com> writes:

> Annotations do not change runtime behavior.
> This commit *only* adds annotations.
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
> Reviewed-by: Cleber Rosa <crosa@redhat.com>
> ---
>  scripts/qapi/expr.py  | 71 ++++++++++++++++++++++++++++---------------
>  scripts/qapi/mypy.ini |  5 ---
>  2 files changed, 46 insertions(+), 30 deletions(-)
>
> diff --git a/scripts/qapi/expr.py b/scripts/qapi/expr.py
> index f45d6be1f4c..df6c64950fa 100644
> --- a/scripts/qapi/expr.py
> +++ b/scripts/qapi/expr.py
> @@ -15,7 +15,14 @@
>  # See the COPYING file in the top-level directory.
>  
>  import re
> -from typing import MutableMapping, Optional, cast
> +from typing import (
> +    Iterable,
> +    List,
> +    MutableMapping,
> +    Optional,
> +    Union,
> +    cast,
> +)
>  
>  from .common import c_name
>  from .error import QAPISemError
> @@ -23,9 +30,10 @@
>  from .source import QAPISourceInfo
>  
>  
> -# Expressions in their raw form are JSON-like structures with arbitrary forms.
> -# Minimally, their top-level form must be a mapping of strings to values.
> -Expression = MutableMapping[str, object]
> +# Arbitrary form for a JSON-like object.
> +_JSObject = MutableMapping[str, object]
> +# Expressions in their raw form are (just) JSON-like objects.
> +Expression = _JSObject

Wat?

>  
>  
>  # Names must be letters, numbers, -, and _.  They must start with letter,
> @@ -35,14 +43,19 @@
>                          '[a-zA-Z][a-zA-Z0-9_-]*$')
>  
>  
> -def check_name_is_str(name, info, source):
> +def check_name_is_str(name: object,
> +                      info: QAPISourceInfo,
> +                      source: str) -> None:
>      if not isinstance(name, str):
>          raise QAPISemError(info, "%s requires a string name" % source)
>  
>  
> -def check_name_str(name, info, source,
> -                   allow_optional=False, enum_member=False,
> -                   permit_upper=False):
> +def check_name_str(name: str,
> +                   info: QAPISourceInfo,
> +                   source: str,
> +                   allow_optional: bool = False,
> +                   enum_member: bool = False,
> +                   permit_upper: bool = False) -> None:
>      membername = name
>  
>      if allow_optional and name.startswith('*'):
> @@ -62,16 +75,20 @@ def check_name_str(name, info, source,
>      assert not membername.startswith('*')
>  
>  
> -def check_defn_name_str(name, info, meta):
> +def check_defn_name_str(name: str, info: QAPISourceInfo, meta: str) -> None:
>      check_name_str(name, info, meta, permit_upper=True)
>      if name.endswith('Kind') or name.endswith('List'):
>          raise QAPISemError(
>              info, "%s name should not end in '%s'" % (meta, name[-4:]))
>  
>  
> -def check_keys(value, info, source, required, optional):
> +def check_keys(value: _JSObject,
> +               info: QAPISourceInfo,
> +               source: str,
> +               required: List[str],
> +               optional: List[str]) -> None:
>  
> -    def pprint(elems):
> +    def pprint(elems: Iterable[str]) -> str:
>          return ', '.join("'" + e + "'" for e in sorted(elems))
>  
>      missing = set(required) - set(value)
> @@ -91,7 +108,7 @@ def pprint(elems):
>                 pprint(unknown), pprint(allowed)))
>  
>  
> -def check_flags(expr, info):
> +def check_flags(expr: Expression, info: QAPISourceInfo) -> None:
>      for key in ['gen', 'success-response']:
>          if key in expr and expr[key] is not False:
>              raise QAPISemError(
> @@ -109,9 +126,9 @@ def check_flags(expr, info):
>                                   "are incompatible")
>  
>  
> -def check_if(expr, info, source):
> +def check_if(expr: _JSObject, info: QAPISourceInfo, source: str) -> None:
>  
> -    def check_if_str(ifcond):
> +    def check_if_str(ifcond: object) -> None:
>          if not isinstance(ifcond, str):
>              raise QAPISemError(
>                  info,
> @@ -137,7 +154,7 @@ def check_if_str(ifcond):
>          expr['if'] = [ifcond]
>  
>  
> -def normalize_members(members):
> +def normalize_members(members: object) -> None:
>      if isinstance(members, dict):
>          for key, arg in members.items():
>              if isinstance(arg, dict):
> @@ -145,8 +162,11 @@ def normalize_members(members):
>              members[key] = {'type': arg}
>  
>  
> -def check_type(value, info, source,
> -               allow_array=False, allow_dict=False):
> +def check_type(value: Optional[object],
> +               info: QAPISourceInfo,
> +               source: str,
> +               allow_array: bool = False,
> +               allow_dict: Union[bool, str] = False) -> None:
>      if value is None:
>          return
>  
> @@ -190,7 +210,8 @@ def check_type(value, info, source,
>          check_type(arg['type'], info, key_source, allow_array=True)
>  
>  
> -def check_features(features, info):
> +def check_features(features: Optional[object],
> +                   info: QAPISourceInfo) -> None:
>      if features is None:
>          return
>      if not isinstance(features, list):
> @@ -207,7 +228,7 @@ def check_features(features, info):
>          check_if(f, info, source)
>  
>  
> -def check_enum(expr, info):
> +def check_enum(expr: Expression, info: QAPISourceInfo) -> None:
>      name = expr['enum']
>      members = expr['data']
>      prefix = expr.get('prefix')
> @@ -231,7 +252,7 @@ def check_enum(expr, info):
>          check_if(member, info, source)
>  
>  
> -def check_struct(expr, info):
> +def check_struct(expr: Expression, info: QAPISourceInfo) -> None:
>      name = cast(str, expr['struct'])  # Asserted in check_exprs
>      members = expr['data']
>  
> @@ -239,7 +260,7 @@ def check_struct(expr, info):
>      check_type(expr.get('base'), info, "'base'")
>  
>  
> -def check_union(expr, info):
> +def check_union(expr: Expression, info: QAPISourceInfo) -> None:
>      name = cast(str, expr['union'])  # Asserted in check_exprs
>      base = expr.get('base')
>      discriminator = expr.get('discriminator')
> @@ -265,7 +286,7 @@ def check_union(expr, info):
>          check_type(value['type'], info, source, allow_array=not base)
>  
>  
> -def check_alternate(expr, info):
> +def check_alternate(expr: Expression, info: QAPISourceInfo) -> None:
>      members = expr['data']
>  
>      if not members:
> @@ -282,7 +303,7 @@ def check_alternate(expr, info):
>          check_type(value['type'], info, source)
>  
>  
> -def check_command(expr, info):
> +def check_command(expr: Expression, info: QAPISourceInfo) -> None:
>      args = expr.get('data')
>      rets = expr.get('returns')
>      boxed = expr.get('boxed', False)
> @@ -293,7 +314,7 @@ def check_command(expr, info):
>      check_type(rets, info, "'returns'", allow_array=True)
>  
>  
> -def check_event(expr, info):
> +def check_event(expr: Expression, info: QAPISourceInfo) -> None:
>      args = expr.get('data')
>      boxed = expr.get('boxed', False)
>  
> @@ -302,7 +323,7 @@ def check_event(expr, info):
>      check_type(args, info, "'data'", allow_dict=not boxed)
>  
>  
> -def check_exprs(exprs):
> +def check_exprs(exprs: List[_JSObject]) -> List[_JSObject]:
>      for expr_elem in exprs:
>          # Expression
>          assert isinstance(expr_elem['expr'], dict)
> diff --git a/scripts/qapi/mypy.ini b/scripts/qapi/mypy.ini
> index 0a000d58b37..7797c834328 100644
> --- a/scripts/qapi/mypy.ini
> +++ b/scripts/qapi/mypy.ini
> @@ -8,11 +8,6 @@ disallow_untyped_defs = False
>  disallow_incomplete_defs = False
>  check_untyped_defs = False
>  
> -[mypy-qapi.expr]
> -disallow_untyped_defs = False
> -disallow_incomplete_defs = False
> -check_untyped_defs = False
> -
>  [mypy-qapi.parser]
>  disallow_untyped_defs = False
>  disallow_incomplete_defs = False

When to use _JSObject, and when Expression?