[PATCH v2 08/16] qapi/expr.py: add type hint annotations

[John Snow <jsnow@redhat.com>]

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 b8720b723377..b393ccd30e92 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
 
 
 # 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 c0f2a58306de..df9b05e4ab36 100644
--- a/scripts/qapi/mypy.ini
+++ b/scripts/qapi/mypy.ini
@@ -9,11 +9,6 @@ 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
-- 
2.26.2