[PATCH v6 17/19] qapi/introspect.py: Type _gen_tree variants as Sequence[str]

John Snow posted 19 patches 4 years, 11 months ago
Maintainers: Markus Armbruster <armbru@redhat.com>, Michael Roth <michael.roth@amd.com>
[PATCH v6 17/19] qapi/introspect.py: Type _gen_tree variants as Sequence[str]
Posted by John Snow 4 years, 11 months ago
Optional[List] is clunky; an empty sequence can more elegantly convey
"no variants". By downgrading "List" to "Sequence", we can also accept
tuples; this is useful for the empty tuple specifically, which we may
use as a default parameter because it is immutable.

Signed-off-by: John Snow <jsnow@redhat.com>
---
 scripts/qapi/introspect.py | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/scripts/qapi/introspect.py b/scripts/qapi/introspect.py
index 649225988d1..e4d31a59503 100644
--- a/scripts/qapi/introspect.py
+++ b/scripts/qapi/introspect.py
@@ -247,13 +247,13 @@ def _use_type(self, typ: QAPISchemaType) -> str:
         return self._name(typ.name)
 
     @staticmethod
-    def _gen_features(features: List[QAPISchemaFeature]
+    def _gen_features(features: Sequence[QAPISchemaFeature]
                       ) -> List[Annotated[str]]:
         return [Annotated(f.name, f.ifcond) for f in features]
 
     def _gen_tree(self, name: str, mtype: str, obj: Dict[str, object],
                   ifcond: Sequence[str],
-                  features: Optional[List[QAPISchemaFeature]]) -> None:
+                  features: Sequence[QAPISchemaFeature] = ()) -> None:
         """
         Build and append a SchemaInfo object to self._trees.
 
@@ -261,7 +261,8 @@ def _gen_tree(self, name: str, mtype: str, obj: Dict[str, object],
         :param mtype: The entity's meta-type.
         :param obj: Additional entity fields, as appropriate for the meta-type.
         :param ifcond: Sequence of conditionals that apply to this entity.
-        :param features: Optional features field for SchemaInfo.
+        :param features: Optional, The features field for SchemaInfo.
+                         Will be omitted from the output if empty.
         """
         comment: Optional[str] = None
         if mtype not in ('command', 'event', 'builtin', 'array'):
@@ -298,7 +299,7 @@ def _gen_variant(self, variant: QAPISchemaVariant
 
     def visit_builtin_type(self, name: str, info: Optional[QAPISourceInfo],
                            json_type: str) -> None:
-        self._gen_tree(name, 'builtin', {'json-type': json_type}, [], None)
+        self._gen_tree(name, 'builtin', {'json-type': json_type}, [])
 
     def visit_enum_type(self, name: str, info: Optional[QAPISourceInfo],
                         ifcond: Sequence[str],
@@ -316,7 +317,7 @@ def visit_array_type(self, name: str, info: Optional[QAPISourceInfo],
                          element_type: QAPISchemaType) -> None:
         element = self._use_type(element_type)
         self._gen_tree('[' + element + ']', 'array', {'element-type': element},
-                       ifcond, None)
+                       ifcond)
 
     def visit_object_type_flat(self, name: str, info: Optional[QAPISourceInfo],
                                ifcond: Sequence[str],
-- 
2.29.2


Re: [PATCH v6 17/19] qapi/introspect.py: Type _gen_tree variants as Sequence[str]
Posted by Markus Armbruster 4 years, 11 months ago
John Snow <jsnow@redhat.com> writes:

> Optional[List] is clunky; an empty sequence can more elegantly convey
> "no variants". By downgrading "List" to "Sequence", we can also accept
> tuples; this is useful for the empty tuple specifically, which we may
> use as a default parameter because it is immutable.
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
>  scripts/qapi/introspect.py | 11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/scripts/qapi/introspect.py b/scripts/qapi/introspect.py
> index 649225988d1..e4d31a59503 100644
> --- a/scripts/qapi/introspect.py
> +++ b/scripts/qapi/introspect.py
> @@ -247,13 +247,13 @@ def _use_type(self, typ: QAPISchemaType) -> str:
>          return self._name(typ.name)
>  
>      @staticmethod
> -    def _gen_features(features: List[QAPISchemaFeature]
> +    def _gen_features(features: Sequence[QAPISchemaFeature]
>                        ) -> List[Annotated[str]]:
>          return [Annotated(f.name, f.ifcond) for f in features]
>  
>      def _gen_tree(self, name: str, mtype: str, obj: Dict[str, object],
>                    ifcond: Sequence[str],
> -                  features: Optional[List[QAPISchemaFeature]]) -> None:
> +                  features: Sequence[QAPISchemaFeature] = ()) -> None:
>          """
>          Build and append a SchemaInfo object to self._trees.
>  
> @@ -261,7 +261,8 @@ def _gen_tree(self, name: str, mtype: str, obj: Dict[str, object],
>          :param mtype: The entity's meta-type.
>          :param obj: Additional entity fields, as appropriate for the meta-type.
>          :param ifcond: Sequence of conditionals that apply to this entity.
> -        :param features: Optional features field for SchemaInfo.
> +        :param features: Optional, The features field for SchemaInfo.

Downcase "The".

> +                         Will be omitted from the output if empty.
>          """
>          comment: Optional[str] = None
>          if mtype not in ('command', 'event', 'builtin', 'array'):
> @@ -298,7 +299,7 @@ def _gen_variant(self, variant: QAPISchemaVariant
>  
>      def visit_builtin_type(self, name: str, info: Optional[QAPISourceInfo],
>                             json_type: str) -> None:
> -        self._gen_tree(name, 'builtin', {'json-type': json_type}, [], None)
> +        self._gen_tree(name, 'builtin', {'json-type': json_type}, [])
>  
>      def visit_enum_type(self, name: str, info: Optional[QAPISourceInfo],
>                          ifcond: Sequence[str],
> @@ -316,7 +317,7 @@ def visit_array_type(self, name: str, info: Optional[QAPISourceInfo],
>                           element_type: QAPISchemaType) -> None:
>          element = self._use_type(element_type)
>          self._gen_tree('[' + element + ']', 'array', {'element-type': element},
> -                       ifcond, None)
> +                       ifcond)
>  
>      def visit_object_type_flat(self, name: str, info: Optional[QAPISourceInfo],
>                                 ifcond: Sequence[str],

Marginal by itself.  Might be worth it as part of a more general move
away from Optional[List[...]].  See also next patch.


Re: [PATCH v6 17/19] qapi/introspect.py: Type _gen_tree variants as Sequence[str]
Posted by John Snow 4 years, 11 months ago
On 2/16/21 4:10 AM, Markus Armbruster wrote:
> John Snow <jsnow@redhat.com> writes:
> 
>> Optional[List] is clunky; an empty sequence can more elegantly convey
>> "no variants". By downgrading "List" to "Sequence", we can also accept
>> tuples; this is useful for the empty tuple specifically, which we may
>> use as a default parameter because it is immutable.
>>
>> Signed-off-by: John Snow <jsnow@redhat.com>
>> ---
>>   scripts/qapi/introspect.py | 11 ++++++-----
>>   1 file changed, 6 insertions(+), 5 deletions(-)
>>
>> diff --git a/scripts/qapi/introspect.py b/scripts/qapi/introspect.py
>> index 649225988d1..e4d31a59503 100644
>> --- a/scripts/qapi/introspect.py
>> +++ b/scripts/qapi/introspect.py
>> @@ -247,13 +247,13 @@ def _use_type(self, typ: QAPISchemaType) -> str:
>>           return self._name(typ.name)
>>   
>>       @staticmethod
>> -    def _gen_features(features: List[QAPISchemaFeature]
>> +    def _gen_features(features: Sequence[QAPISchemaFeature]
>>                         ) -> List[Annotated[str]]:
>>           return [Annotated(f.name, f.ifcond) for f in features]
>>   
>>       def _gen_tree(self, name: str, mtype: str, obj: Dict[str, object],
>>                     ifcond: Sequence[str],
>> -                  features: Optional[List[QAPISchemaFeature]]) -> None:
>> +                  features: Sequence[QAPISchemaFeature] = ()) -> None:
>>           """
>>           Build and append a SchemaInfo object to self._trees.
>>   
>> @@ -261,7 +261,8 @@ def _gen_tree(self, name: str, mtype: str, obj: Dict[str, object],
>>           :param mtype: The entity's meta-type.
>>           :param obj: Additional entity fields, as appropriate for the meta-type.
>>           :param ifcond: Sequence of conditionals that apply to this entity.
>> -        :param features: Optional features field for SchemaInfo.
>> +        :param features: Optional, The features field for SchemaInfo.
> 
> Downcase "The".
> 
>> +                         Will be omitted from the output if empty.
>>           """
>>           comment: Optional[str] = None
>>           if mtype not in ('command', 'event', 'builtin', 'array'):
>> @@ -298,7 +299,7 @@ def _gen_variant(self, variant: QAPISchemaVariant
>>   
>>       def visit_builtin_type(self, name: str, info: Optional[QAPISourceInfo],
>>                              json_type: str) -> None:
>> -        self._gen_tree(name, 'builtin', {'json-type': json_type}, [], None)
>> +        self._gen_tree(name, 'builtin', {'json-type': json_type}, [])
>>   
>>       def visit_enum_type(self, name: str, info: Optional[QAPISourceInfo],
>>                           ifcond: Sequence[str],
>> @@ -316,7 +317,7 @@ def visit_array_type(self, name: str, info: Optional[QAPISourceInfo],
>>                            element_type: QAPISchemaType) -> None:
>>           element = self._use_type(element_type)
>>           self._gen_tree('[' + element + ']', 'array', {'element-type': element},
>> -                       ifcond, None)
>> +                       ifcond)
>>   
>>       def visit_object_type_flat(self, name: str, info: Optional[QAPISourceInfo],
>>                                  ifcond: Sequence[str],
> 
> Marginal by itself.  Might be worth it as part of a more general move
> away from Optional[List[...]].  See also next patch.
> 

Yep, it's tiny. Still, maybe worth taking just to remove a bad habit 
from the code in case of cargo-culting?

Go with whatcha feel, it's a style nit you raised -- I'm not sure I'll 
remember to do a more thorough pass after pt6 is done.

ACK to change the comment casing if you take these.

--js