[PATCH v2 03/19] qapi: create QAPISchemaDefinition

John Snow posted 19 patches 10 months ago
Maintainers: Markus Armbruster <armbru@redhat.com>, Michael Roth <michael.roth@amd.com>
There is a newer version of this series
[PATCH v2 03/19] qapi: create QAPISchemaDefinition
Posted by John Snow 10 months ago
Include entities don't have names, but we generally expect "entities" to
have names. Reclassify all entities with names as *definitions*, leaving
the nameless include entities as QAPISchemaEntity instances.

This is primarily to help simplify typing around expectations of what
callers expect for properties of an "entity".

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
---
 scripts/qapi/schema.py | 117 ++++++++++++++++++++++++-----------------
 1 file changed, 70 insertions(+), 47 deletions(-)

diff --git a/scripts/qapi/schema.py b/scripts/qapi/schema.py
index b7830672e57..e39ed972a80 100644
--- a/scripts/qapi/schema.py
+++ b/scripts/qapi/schema.py
@@ -55,14 +55,14 @@ def is_present(self):
 
 
 class QAPISchemaEntity:
-    meta: Optional[str] = None
+    """
+    QAPISchemaEntity represents all schema entities.
 
-    def __init__(self, name: str, info, doc, ifcond=None, features=None):
-        assert name is None or isinstance(name, str)
-        for f in features or []:
-            assert isinstance(f, QAPISchemaFeature)
-            f.set_defined_in(name)
-        self.name = name
+    Notably, this includes both named and un-named entities, such as
+    include directives. Entities with names are represented by the
+    more specific sub-class `QAPISchemaDefinition` instead.
+    """
+    def __init__(self, info):
         self._module = None
         # For explicitly defined entities, info points to the (explicit)
         # definition.  For builtins (and their arrays), info is None.
@@ -70,14 +70,50 @@ def __init__(self, name: str, info, doc, ifcond=None, features=None):
         # triggered the implicit definition (there may be more than one
         # such place).
         self.info = info
+        self._checked = False
+
+    def __repr__(self):
+        return "<%s at 0x%x>" % (type(self).__name__, id(self))
+
+    def check(self, schema):
+        # pylint: disable=unused-argument
+        self._checked = True
+
+    def connect_doc(self, doc=None):
+        pass
+
+    def check_doc(self):
+        pass
+
+    def _set_module(self, schema, info):
+        assert self._checked
+        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
+        self._module = schema.module_by_fname(fname)
+        self._module.add_entity(self)
+
+    def set_module(self, schema):
+        self._set_module(schema, self.info)
+
+    def visit(self, visitor):
+        # pylint: disable=unused-argument
+        assert self._checked
+
+
+class QAPISchemaDefinition(QAPISchemaEntity):
+    meta: Optional[str] = None
+
+    def __init__(self, name: str, info, doc, ifcond=None, features=None):
+        assert isinstance(name, str)
+        super().__init__(info)
+        for f in features or []:
+            assert isinstance(f, QAPISchemaFeature)
+            f.set_defined_in(name)
+        self.name = name
         self.doc = doc
         self._ifcond = ifcond or QAPISchemaIfCond()
         self.features = features or []
-        self._checked = False
 
     def __repr__(self):
-        if self.name is None:
-            return "<%s at 0x%x>" % (type(self).__name__, id(self))
         return "<%s:%s at 0x%x>" % (type(self).__name__, self.name,
                                     id(self))
 
@@ -102,15 +138,6 @@ def check_doc(self):
         if self.doc:
             self.doc.check()
 
-    def _set_module(self, schema, info):
-        assert self._checked
-        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
-        self._module = schema.module_by_fname(fname)
-        self._module.add_entity(self)
-
-    def set_module(self, schema):
-        self._set_module(schema, self.info)
-
     @property
     def ifcond(self):
         assert self._checked
@@ -119,10 +146,6 @@ def ifcond(self):
     def is_implicit(self):
         return not self.info
 
-    def visit(self, visitor):
-        # pylint: disable=unused-argument
-        assert self._checked
-
     def describe(self):
         assert self.meta
         return "%s '%s'" % (self.meta, self.name)
@@ -222,7 +245,7 @@ def visit(self, visitor):
 
 class QAPISchemaInclude(QAPISchemaEntity):
     def __init__(self, sub_module, info):
-        super().__init__(None, info, None)
+        super().__init__(info)
         self._sub_module = sub_module
 
     def visit(self, visitor):
@@ -230,7 +253,7 @@ def visit(self, visitor):
         visitor.visit_include(self._sub_module.name, self.info)
 
 
-class QAPISchemaType(QAPISchemaEntity):
+class QAPISchemaType(QAPISchemaDefinition):
     # Return the C type for common use.
     # For the types we commonly box, this is a pointer type.
     def c_type(self):
@@ -801,7 +824,7 @@ def __init__(self, name, info, typ, ifcond=None):
         super().__init__(name, info, typ, False, ifcond)
 
 
-class QAPISchemaCommand(QAPISchemaEntity):
+class QAPISchemaCommand(QAPISchemaDefinition):
     meta = 'command'
 
     def __init__(self, name, info, doc, ifcond, features,
@@ -872,7 +895,7 @@ def visit(self, visitor):
             self.coroutine)
 
 
-class QAPISchemaEvent(QAPISchemaEntity):
+class QAPISchemaEvent(QAPISchemaDefinition):
     meta = 'event'
 
     def __init__(self, name, info, doc, ifcond, features, arg_type, boxed):
@@ -943,11 +966,12 @@ def __init__(self, fname):
         self.check()
 
     def _def_entity(self, ent):
+        self._entity_list.append(ent)
+
+    def _def_definition(self, ent):
         # Only the predefined types are allowed to not have info
         assert ent.info or self._predefining
-        self._entity_list.append(ent)
-        if ent.name is None:
-            return
+        self._def_entity(ent)
         # TODO reject names that differ only in '_' vs. '.'  vs. '-',
         # because they're liable to clash in generated C.
         other_ent = self._entity_dict.get(ent.name)
@@ -1001,7 +1025,7 @@ def _def_include(self, expr: QAPIExpression):
             QAPISchemaInclude(self._make_module(include), expr.info))
 
     def _def_builtin_type(self, name, json_type, c_type):
-        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
+        self._def_definition(QAPISchemaBuiltinType(name, json_type, c_type))
         # Instantiating only the arrays that are actually used would
         # be nice, but we can't as long as their generated code
         # (qapi-builtin-types.[ch]) may be shared by some other
@@ -1027,15 +1051,15 @@ def _def_predefineds(self):
             self._def_builtin_type(*t)
         self.the_empty_object_type = QAPISchemaObjectType(
             'q_empty', None, None, None, None, None, [], None)
-        self._def_entity(self.the_empty_object_type)
+        self._def_definition(self.the_empty_object_type)
 
         qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
                   'qbool']
         qtype_values = self._make_enum_members(
             [{'name': n} for n in qtypes], None)
 
-        self._def_entity(QAPISchemaEnumType('QType', None, None, None, None,
-                                            qtype_values, 'QTYPE'))
+        self._def_definition(QAPISchemaEnumType('QType', None, None, None,
+                                                None, qtype_values, 'QTYPE'))
 
     def _make_features(self, features, info):
         if features is None:
@@ -1057,7 +1081,7 @@ def _make_enum_members(self, values, info):
     def _make_array_type(self, element_type, info):
         name = element_type + 'List'    # reserved by check_defn_name_str()
         if not self.lookup_type(name):
-            self._def_entity(QAPISchemaArrayType(name, info, element_type))
+            self._def_definition(QAPISchemaArrayType(name, info, element_type))
         return name
 
     def _make_implicit_object_type(self, name, info, ifcond, role, members):
@@ -1072,7 +1096,7 @@ def _make_implicit_object_type(self, name, info, ifcond, role, members):
             # later.
             pass
         else:
-            self._def_entity(QAPISchemaObjectType(
+            self._def_definition(QAPISchemaObjectType(
                 name, info, None, ifcond, None, None, members, None))
         return name
 
@@ -1083,7 +1107,7 @@ def _def_enum_type(self, expr: QAPIExpression):
         ifcond = QAPISchemaIfCond(expr.get('if'))
         info = expr.info
         features = self._make_features(expr.get('features'), info)
-        self._def_entity(QAPISchemaEnumType(
+        self._def_definition(QAPISchemaEnumType(
             name, info, expr.doc, ifcond, features,
             self._make_enum_members(data, info), prefix))
 
@@ -1111,7 +1135,7 @@ def _def_struct_type(self, expr: QAPIExpression):
         info = expr.info
         ifcond = QAPISchemaIfCond(expr.get('if'))
         features = self._make_features(expr.get('features'), info)
-        self._def_entity(QAPISchemaObjectType(
+        self._def_definition(QAPISchemaObjectType(
             name, info, expr.doc, ifcond, features, base,
             self._make_members(data, info),
             None))
@@ -1141,7 +1165,7 @@ def _def_union_type(self, expr: QAPIExpression):
                                info)
             for (key, value) in data.items()]
         members: List[QAPISchemaObjectTypeMember] = []
-        self._def_entity(
+        self._def_definition(
             QAPISchemaObjectType(name, info, expr.doc, ifcond, features,
                                  base, members,
                                  QAPISchemaVariants(
@@ -1160,7 +1184,7 @@ def _def_alternate_type(self, expr: QAPIExpression):
                                info)
             for (key, value) in data.items()]
         tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
-        self._def_entity(
+        self._def_definition(
             QAPISchemaAlternateType(
                 name, info, expr.doc, ifcond, features,
                 QAPISchemaVariants(None, info, tag_member, variants)))
@@ -1185,11 +1209,10 @@ def _def_command(self, expr: QAPIExpression):
         if isinstance(rets, list):
             assert len(rets) == 1
             rets = self._make_array_type(rets[0], info)
-        self._def_entity(QAPISchemaCommand(name, info, expr.doc, ifcond,
-                                           features, data, rets,
-                                           gen, success_response,
-                                           boxed, allow_oob, allow_preconfig,
-                                           coroutine))
+        self._def_definition(
+            QAPISchemaCommand(name, info, expr.doc, ifcond, features, data,
+                              rets, gen, success_response, boxed, allow_oob,
+                              allow_preconfig, coroutine))
 
     def _def_event(self, expr: QAPIExpression):
         name = expr['event']
@@ -1202,8 +1225,8 @@ def _def_event(self, expr: QAPIExpression):
             data = self._make_implicit_object_type(
                 name, info, ifcond,
                 'arg', self._make_members(data, info))
-        self._def_entity(QAPISchemaEvent(name, info, expr.doc, ifcond,
-                                         features, data, boxed))
+        self._def_definition(QAPISchemaEvent(name, info, expr.doc, ifcond,
+                                             features, data, boxed))
 
     def _def_exprs(self, exprs):
         for expr in exprs:
-- 
2.43.0
Re: [PATCH v2 03/19] qapi: create QAPISchemaDefinition
Posted by Markus Armbruster 10 months ago
John Snow <jsnow@redhat.com> writes:

> Include entities don't have names, but we generally expect "entities" to
> have names. Reclassify all entities with names as *definitions*, leaving
> the nameless include entities as QAPISchemaEntity instances.
>
> This is primarily to help simplify typing around expectations of what
> callers expect for properties of an "entity".
>
> Suggested-by: Markus Armbruster <armbru@redhat.com>
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
>  scripts/qapi/schema.py | 117 ++++++++++++++++++++++++-----------------
>  1 file changed, 70 insertions(+), 47 deletions(-)
>
> diff --git a/scripts/qapi/schema.py b/scripts/qapi/schema.py
> index b7830672e57..e39ed972a80 100644
> --- a/scripts/qapi/schema.py
> +++ b/scripts/qapi/schema.py
> @@ -55,14 +55,14 @@ def is_present(self):
>  
>  
>  class QAPISchemaEntity:
> -    meta: Optional[str] = None
> +    """
> +    QAPISchemaEntity represents all schema entities.
>  
> -    def __init__(self, name: str, info, doc, ifcond=None, features=None):
> -        assert name is None or isinstance(name, str)
> -        for f in features or []:
> -            assert isinstance(f, QAPISchemaFeature)
> -            f.set_defined_in(name)
> -        self.name = name
> +    Notably, this includes both named and un-named entities, such as
> +    include directives. Entities with names are represented by the
> +    more specific sub-class `QAPISchemaDefinition` instead.
> +    """

Hmm.  What about:

       """
       A schema entity.

       This is either a directive, such as include, or a definition.
       The latter use sub-class `QAPISchemaDefinition`.
       """

> +    def __init__(self, info):
>          self._module = None
>          # For explicitly defined entities, info points to the (explicit)
>          # definition.  For builtins (and their arrays), info is None.
> @@ -70,14 +70,50 @@ def __init__(self, name: str, info, doc, ifcond=None, features=None):
>          # triggered the implicit definition (there may be more than one
>          # such place).
>          self.info = info
> +        self._checked = False
> +
> +    def __repr__(self):
> +        return "<%s at 0x%x>" % (type(self).__name__, id(self))
> +
> +    def check(self, schema):
> +        # pylint: disable=unused-argument
> +        self._checked = True
> +
> +    def connect_doc(self, doc=None):
> +        pass
> +
> +    def check_doc(self):
> +        pass
> +
> +    def _set_module(self, schema, info):
> +        assert self._checked
> +        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
> +        self._module = schema.module_by_fname(fname)
> +        self._module.add_entity(self)
> +
> +    def set_module(self, schema):
> +        self._set_module(schema, self.info)
> +
> +    def visit(self, visitor):
> +        # pylint: disable=unused-argument
> +        assert self._checked
> +
> +
> +class QAPISchemaDefinition(QAPISchemaEntity):
> +    meta: Optional[str] = None
> +
> +    def __init__(self, name: str, info, doc, ifcond=None, features=None):
> +        assert isinstance(name, str)
> +        super().__init__(info)
> +        for f in features or []:
> +            assert isinstance(f, QAPISchemaFeature)
> +            f.set_defined_in(name)
> +        self.name = name
>          self.doc = doc
>          self._ifcond = ifcond or QAPISchemaIfCond()
>          self.features = features or []
> -        self._checked = False
>  
>      def __repr__(self):
> -        if self.name is None:
> -            return "<%s at 0x%x>" % (type(self).__name__, id(self))
>          return "<%s:%s at 0x%x>" % (type(self).__name__, self.name,
>                                      id(self))
>  
> @@ -102,15 +138,6 @@ def check_doc(self):
       def check(self, schema):
           # pylint: disable=unused-argument
           assert not self._checked
           seen = {}
           for f in self.features:
               f.check_clash(self.info, seen)
           self._checked = True

       def connect_doc(self, doc=None):
           doc = doc or self.doc
           if doc:
               for f in self.features:
                   doc.connect_feature(f)

       def check_doc(self):
>          if self.doc:
>              self.doc.check()

No super().FOO()?

>  
> -    def _set_module(self, schema, info):
> -        assert self._checked
> -        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
> -        self._module = schema.module_by_fname(fname)
> -        self._module.add_entity(self)
> -
> -    def set_module(self, schema):
> -        self._set_module(schema, self.info)
> -
>      @property
>      def ifcond(self):
>          assert self._checked
> @@ -119,10 +146,6 @@ def ifcond(self):
>      def is_implicit(self):
>          return not self.info
>  
> -    def visit(self, visitor):
> -        # pylint: disable=unused-argument
> -        assert self._checked
> -
>      def describe(self):
>          assert self.meta
>          return "%s '%s'" % (self.meta, self.name)
> @@ -222,7 +245,7 @@ def visit(self, visitor):
>  
>  class QAPISchemaInclude(QAPISchemaEntity):
>      def __init__(self, sub_module, info):
> -        super().__init__(None, info, None)
> +        super().__init__(info)
>          self._sub_module = sub_module
>  
>      def visit(self, visitor):
> @@ -230,7 +253,7 @@ def visit(self, visitor):
>          visitor.visit_include(self._sub_module.name, self.info)
>  
>  
> -class QAPISchemaType(QAPISchemaEntity):
> +class QAPISchemaType(QAPISchemaDefinition):
>      # Return the C type for common use.
>      # For the types we commonly box, this is a pointer type.
>      def c_type(self):
> @@ -801,7 +824,7 @@ def __init__(self, name, info, typ, ifcond=None):
>          super().__init__(name, info, typ, False, ifcond)
>  
>  
> -class QAPISchemaCommand(QAPISchemaEntity):
> +class QAPISchemaCommand(QAPISchemaDefinition):
>      meta = 'command'
>  
>      def __init__(self, name, info, doc, ifcond, features,
> @@ -872,7 +895,7 @@ def visit(self, visitor):
>              self.coroutine)
>  
>  
> -class QAPISchemaEvent(QAPISchemaEntity):
> +class QAPISchemaEvent(QAPISchemaDefinition):
>      meta = 'event'
>  
>      def __init__(self, name, info, doc, ifcond, features, arg_type, boxed):
> @@ -943,11 +966,12 @@ def __init__(self, fname):
>          self.check()
>  
>      def _def_entity(self, ent):
> +        self._entity_list.append(ent)
> +
> +    def _def_definition(self, ent):

Name the argument @defn instead of @ent?

>          # Only the predefined types are allowed to not have info
>          assert ent.info or self._predefining
> -        self._entity_list.append(ent)
> -        if ent.name is None:
> -            return
> +        self._def_entity(ent)
>          # TODO reject names that differ only in '_' vs. '.'  vs. '-',
>          # because they're liable to clash in generated C.
>          other_ent = self._entity_dict.get(ent.name)
> @@ -1001,7 +1025,7 @@ def _def_include(self, expr: QAPIExpression):
>              QAPISchemaInclude(self._make_module(include), expr.info))
>  
>      def _def_builtin_type(self, name, json_type, c_type):
> -        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
> +        self._def_definition(QAPISchemaBuiltinType(name, json_type, c_type))
>          # Instantiating only the arrays that are actually used would
>          # be nice, but we can't as long as their generated code
>          # (qapi-builtin-types.[ch]) may be shared by some other
> @@ -1027,15 +1051,15 @@ def _def_predefineds(self):
>              self._def_builtin_type(*t)
>          self.the_empty_object_type = QAPISchemaObjectType(
>              'q_empty', None, None, None, None, None, [], None)
> -        self._def_entity(self.the_empty_object_type)
> +        self._def_definition(self.the_empty_object_type)
>  
>          qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
>                    'qbool']
>          qtype_values = self._make_enum_members(
>              [{'name': n} for n in qtypes], None)
>  
> -        self._def_entity(QAPISchemaEnumType('QType', None, None, None, None,
> -                                            qtype_values, 'QTYPE'))
> +        self._def_definition(QAPISchemaEnumType('QType', None, None, None,
> +                                                None, qtype_values, 'QTYPE'))

The long identifiers squeeze the (also long) argument list against the
right margin.  What about:

           self._def_definition(QAPISchemaEnumType(
               'QType', None, None, None, None, qtype_values, 'QTYPE'))

or

           self._def_definition(
               QAPISchemaEnumType('QType', None, None, None, None,
                                  qtype_values, 'QTYPE'))

We already use the former style elsewhere, visible below.

You add one in the latter style in the second to last hunk.

Pick one style and stick ot it?

>  
>      def _make_features(self, features, info):
>          if features is None:
> @@ -1057,7 +1081,7 @@ def _make_enum_members(self, values, info):
>      def _make_array_type(self, element_type, info):
>          name = element_type + 'List'    # reserved by check_defn_name_str()
>          if not self.lookup_type(name):
> -            self._def_entity(QAPISchemaArrayType(name, info, element_type))
> +            self._def_definition(QAPISchemaArrayType(name, info, element_type))

               self._def_definition(QAPISchemaArrayType(
                   name, info, element_type))

or

               self._def_definition(
                   QAPISchemaArrayType(name, info, element_type))

>          return name
>  
>      def _make_implicit_object_type(self, name, info, ifcond, role, members):
> @@ -1072,7 +1096,7 @@ def _make_implicit_object_type(self, name, info, ifcond, role, members):
>              # later.
>              pass
>          else:
> -            self._def_entity(QAPISchemaObjectType(
> +            self._def_definition(QAPISchemaObjectType(
>                  name, info, None, ifcond, None, None, members, None))
>          return name
>  
> @@ -1083,7 +1107,7 @@ def _def_enum_type(self, expr: QAPIExpression):
>          ifcond = QAPISchemaIfCond(expr.get('if'))
>          info = expr.info
>          features = self._make_features(expr.get('features'), info)
> -        self._def_entity(QAPISchemaEnumType(
> +        self._def_definition(QAPISchemaEnumType(
>              name, info, expr.doc, ifcond, features,
>              self._make_enum_members(data, info), prefix))
>  
> @@ -1111,7 +1135,7 @@ def _def_struct_type(self, expr: QAPIExpression):
>          info = expr.info
>          ifcond = QAPISchemaIfCond(expr.get('if'))
>          features = self._make_features(expr.get('features'), info)
> -        self._def_entity(QAPISchemaObjectType(
> +        self._def_definition(QAPISchemaObjectType(
>              name, info, expr.doc, ifcond, features, base,
>              self._make_members(data, info),
>              None))
> @@ -1141,7 +1165,7 @@ def _def_union_type(self, expr: QAPIExpression):
>                                 info)
>              for (key, value) in data.items()]
>          members: List[QAPISchemaObjectTypeMember] = []
> -        self._def_entity(
> +        self._def_definition(
>              QAPISchemaObjectType(name, info, expr.doc, ifcond, features,
>                                   base, members,
>                                   QAPISchemaVariants(
> @@ -1160,7 +1184,7 @@ def _def_alternate_type(self, expr: QAPIExpression):
>                                 info)
>              for (key, value) in data.items()]
>          tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
> -        self._def_entity(
> +        self._def_definition(
>              QAPISchemaAlternateType(
>                  name, info, expr.doc, ifcond, features,
>                  QAPISchemaVariants(None, info, tag_member, variants)))
> @@ -1185,11 +1209,10 @@ def _def_command(self, expr: QAPIExpression):
>          if isinstance(rets, list):
>              assert len(rets) == 1
>              rets = self._make_array_type(rets[0], info)
> -        self._def_entity(QAPISchemaCommand(name, info, expr.doc, ifcond,
> -                                           features, data, rets,
> -                                           gen, success_response,
> -                                           boxed, allow_oob, allow_preconfig,
> -                                           coroutine))
> +        self._def_definition(
> +            QAPISchemaCommand(name, info, expr.doc, ifcond, features, data,
> +                              rets, gen, success_response, boxed, allow_oob,
> +                              allow_preconfig, coroutine))
>  
>      def _def_event(self, expr: QAPIExpression):
>          name = expr['event']
> @@ -1202,8 +1225,8 @@ def _def_event(self, expr: QAPIExpression):
>              data = self._make_implicit_object_type(
>                  name, info, ifcond,
>                  'arg', self._make_members(data, info))
> -        self._def_entity(QAPISchemaEvent(name, info, expr.doc, ifcond,
> -                                         features, data, boxed))
> +        self._def_definition(QAPISchemaEvent(name, info, expr.doc, ifcond,
> +                                             features, data, boxed))
>  
>      def _def_exprs(self, exprs):
>          for expr in exprs:

Slightly more code, but with slightly fewer conditionals.  Feels a bit
cleaner.
Re: [PATCH v2 03/19] qapi: create QAPISchemaDefinition
Posted by John Snow 10 months ago
On Mon, Jan 15, 2024 at 8:16 AM Markus Armbruster <armbru@redhat.com> wrote:
>
> John Snow <jsnow@redhat.com> writes:
>
> > Include entities don't have names, but we generally expect "entities" to
> > have names. Reclassify all entities with names as *definitions*, leaving
> > the nameless include entities as QAPISchemaEntity instances.
> >
> > This is primarily to help simplify typing around expectations of what
> > callers expect for properties of an "entity".
> >
> > Suggested-by: Markus Armbruster <armbru@redhat.com>
> > Signed-off-by: John Snow <jsnow@redhat.com>
> > ---
> >  scripts/qapi/schema.py | 117 ++++++++++++++++++++++++-----------------
> >  1 file changed, 70 insertions(+), 47 deletions(-)
> >
> > diff --git a/scripts/qapi/schema.py b/scripts/qapi/schema.py
> > index b7830672e57..e39ed972a80 100644
> > --- a/scripts/qapi/schema.py
> > +++ b/scripts/qapi/schema.py
> > @@ -55,14 +55,14 @@ def is_present(self):
> >
> >
> >  class QAPISchemaEntity:
> > -    meta: Optional[str] = None
> > +    """
> > +    QAPISchemaEntity represents all schema entities.
> >
> > -    def __init__(self, name: str, info, doc, ifcond=None, features=None):
> > -        assert name is None or isinstance(name, str)
> > -        for f in features or []:
> > -            assert isinstance(f, QAPISchemaFeature)
> > -            f.set_defined_in(name)
> > -        self.name = name
> > +    Notably, this includes both named and un-named entities, such as
> > +    include directives. Entities with names are represented by the
> > +    more specific sub-class `QAPISchemaDefinition` instead.
> > +    """
>
> Hmm.  What about:
>
>        """
>        A schema entity.
>
>        This is either a directive, such as include, or a definition.
>        The latter use sub-class `QAPISchemaDefinition`.
>        """
>

Sure. Key point was just the cookie crumb to the sub-class.

> > +    def __init__(self, info):
> >          self._module = None
> >          # For explicitly defined entities, info points to the (explicit)
> >          # definition.  For builtins (and their arrays), info is None.
> > @@ -70,14 +70,50 @@ def __init__(self, name: str, info, doc, ifcond=None, features=None):
> >          # triggered the implicit definition (there may be more than one
> >          # such place).
> >          self.info = info
> > +        self._checked = False
> > +
> > +    def __repr__(self):
> > +        return "<%s at 0x%x>" % (type(self).__name__, id(self))
> > +
> > +    def check(self, schema):
> > +        # pylint: disable=unused-argument
> > +        self._checked = True
> > +
> > +    def connect_doc(self, doc=None):
> > +        pass
> > +
> > +    def check_doc(self):
> > +        pass
> > +
> > +    def _set_module(self, schema, info):
> > +        assert self._checked
> > +        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
> > +        self._module = schema.module_by_fname(fname)
> > +        self._module.add_entity(self)
> > +
> > +    def set_module(self, schema):
> > +        self._set_module(schema, self.info)
> > +
> > +    def visit(self, visitor):
> > +        # pylint: disable=unused-argument
> > +        assert self._checked
> > +
> > +
> > +class QAPISchemaDefinition(QAPISchemaEntity):
> > +    meta: Optional[str] = None
> > +
> > +    def __init__(self, name: str, info, doc, ifcond=None, features=None):
> > +        assert isinstance(name, str)
> > +        super().__init__(info)
> > +        for f in features or []:
> > +            assert isinstance(f, QAPISchemaFeature)
> > +            f.set_defined_in(name)
> > +        self.name = name
> >          self.doc = doc
> >          self._ifcond = ifcond or QAPISchemaIfCond()
> >          self.features = features or []
> > -        self._checked = False
> >
> >      def __repr__(self):
> > -        if self.name is None:
> > -            return "<%s at 0x%x>" % (type(self).__name__, id(self))
> >          return "<%s:%s at 0x%x>" % (type(self).__name__, self.name,
> >                                      id(self))
> >
> > @@ -102,15 +138,6 @@ def check_doc(self):
>        def check(self, schema):
>            # pylint: disable=unused-argument
>            assert not self._checked
>            seen = {}
>            for f in self.features:
>                f.check_clash(self.info, seen)
>            self._checked = True
>
>        def connect_doc(self, doc=None):
>            doc = doc or self.doc
>            if doc:
>                for f in self.features:
>                    doc.connect_feature(f)
>
>        def check_doc(self):
> >          if self.doc:
> >              self.doc.check()
>
> No super().FOO()?
>

Ah, just an oversight. It worked out because the super method doesn't
do anything anyway. check() and connect_doc() should also use the
super call, probably.

> >
> > -    def _set_module(self, schema, info):
> > -        assert self._checked
> > -        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
> > -        self._module = schema.module_by_fname(fname)
> > -        self._module.add_entity(self)
> > -
> > -    def set_module(self, schema):
> > -        self._set_module(schema, self.info)
> > -
> >      @property
> >      def ifcond(self):
> >          assert self._checked
> > @@ -119,10 +146,6 @@ def ifcond(self):
> >      def is_implicit(self):
> >          return not self.info
> >
> > -    def visit(self, visitor):
> > -        # pylint: disable=unused-argument
> > -        assert self._checked
> > -
> >      def describe(self):
> >          assert self.meta
> >          return "%s '%s'" % (self.meta, self.name)
> > @@ -222,7 +245,7 @@ def visit(self, visitor):
> >
> >  class QAPISchemaInclude(QAPISchemaEntity):
> >      def __init__(self, sub_module, info):
> > -        super().__init__(None, info, None)
> > +        super().__init__(info)
> >          self._sub_module = sub_module
> >
> >      def visit(self, visitor):
> > @@ -230,7 +253,7 @@ def visit(self, visitor):
> >          visitor.visit_include(self._sub_module.name, self.info)
> >
> >
> > -class QAPISchemaType(QAPISchemaEntity):
> > +class QAPISchemaType(QAPISchemaDefinition):
> >      # Return the C type for common use.
> >      # For the types we commonly box, this is a pointer type.
> >      def c_type(self):
> > @@ -801,7 +824,7 @@ def __init__(self, name, info, typ, ifcond=None):
> >          super().__init__(name, info, typ, False, ifcond)
> >
> >
> > -class QAPISchemaCommand(QAPISchemaEntity):
> > +class QAPISchemaCommand(QAPISchemaDefinition):
> >      meta = 'command'
> >
> >      def __init__(self, name, info, doc, ifcond, features,
> > @@ -872,7 +895,7 @@ def visit(self, visitor):
> >              self.coroutine)
> >
> >
> > -class QAPISchemaEvent(QAPISchemaEntity):
> > +class QAPISchemaEvent(QAPISchemaDefinition):
> >      meta = 'event'
> >
> >      def __init__(self, name, info, doc, ifcond, features, arg_type, boxed):
> > @@ -943,11 +966,12 @@ def __init__(self, fname):
> >          self.check()
> >
> >      def _def_entity(self, ent):
> > +        self._entity_list.append(ent)
> > +
> > +    def _def_definition(self, ent):
>
> Name the argument @defn instead of @ent?
>

OK. (Was aiming for less diffstat, but yes.)

> >          # Only the predefined types are allowed to not have info
> >          assert ent.info or self._predefining
> > -        self._entity_list.append(ent)
> > -        if ent.name is None:
> > -            return
> > +        self._def_entity(ent)
> >          # TODO reject names that differ only in '_' vs. '.'  vs. '-',
> >          # because they're liable to clash in generated C.
> >          other_ent = self._entity_dict.get(ent.name)
> > @@ -1001,7 +1025,7 @@ def _def_include(self, expr: QAPIExpression):
> >              QAPISchemaInclude(self._make_module(include), expr.info))
> >
> >      def _def_builtin_type(self, name, json_type, c_type):
> > -        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
> > +        self._def_definition(QAPISchemaBuiltinType(name, json_type, c_type))
> >          # Instantiating only the arrays that are actually used would
> >          # be nice, but we can't as long as their generated code
> >          # (qapi-builtin-types.[ch]) may be shared by some other
> > @@ -1027,15 +1051,15 @@ def _def_predefineds(self):
> >              self._def_builtin_type(*t)
> >          self.the_empty_object_type = QAPISchemaObjectType(
> >              'q_empty', None, None, None, None, None, [], None)
> > -        self._def_entity(self.the_empty_object_type)
> > +        self._def_definition(self.the_empty_object_type)
> >
> >          qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
> >                    'qbool']
> >          qtype_values = self._make_enum_members(
> >              [{'name': n} for n in qtypes], None)
> >
> > -        self._def_entity(QAPISchemaEnumType('QType', None, None, None, None,
> > -                                            qtype_values, 'QTYPE'))
> > +        self._def_definition(QAPISchemaEnumType('QType', None, None, None,
> > +                                                None, qtype_values, 'QTYPE'))
>
> The long identifiers squeeze the (also long) argument list against the
> right margin.  What about:
>
>            self._def_definition(QAPISchemaEnumType(
>                'QType', None, None, None, None, qtype_values, 'QTYPE'))

This is fine to my eyes.

>
> or
>
>            self._def_definition(
>                QAPISchemaEnumType('QType', None, None, None, None,
>                                   qtype_values, 'QTYPE'))
>
> We already use the former style elsewhere, visible below.
>
> You add one in the latter style in the second to last hunk.
>
> Pick one style and stick ot it?

Yeah. I might try to run the black formatter in the end and just stick
to that, if you don't mind a bit of churn in exchange for having it be
a bit more mindless. It would be a big hassle to run it at the
beginning of the series now, though... but I'll fix this instance for
now.

>
> >
> >      def _make_features(self, features, info):
> >          if features is None:
> > @@ -1057,7 +1081,7 @@ def _make_enum_members(self, values, info):
> >      def _make_array_type(self, element_type, info):
> >          name = element_type + 'List'    # reserved by check_defn_name_str()
> >          if not self.lookup_type(name):
> > -            self._def_entity(QAPISchemaArrayType(name, info, element_type))
> > +            self._def_definition(QAPISchemaArrayType(name, info, element_type))
>
>                self._def_definition(QAPISchemaArrayType(
>                    name, info, element_type))
>
> or
>
>                self._def_definition(
>                    QAPISchemaArrayType(name, info, element_type))
>

OK. (79 columns too long for ya?)

> >          return name
> >
> >      def _make_implicit_object_type(self, name, info, ifcond, role, members):
> > @@ -1072,7 +1096,7 @@ def _make_implicit_object_type(self, name, info, ifcond, role, members):
> >              # later.
> >              pass
> >          else:
> > -            self._def_entity(QAPISchemaObjectType(
> > +            self._def_definition(QAPISchemaObjectType(
> >                  name, info, None, ifcond, None, None, members, None))
> >          return name
> >
> > @@ -1083,7 +1107,7 @@ def _def_enum_type(self, expr: QAPIExpression):
> >          ifcond = QAPISchemaIfCond(expr.get('if'))
> >          info = expr.info
> >          features = self._make_features(expr.get('features'), info)
> > -        self._def_entity(QAPISchemaEnumType(
> > +        self._def_definition(QAPISchemaEnumType(
> >              name, info, expr.doc, ifcond, features,
> >              self._make_enum_members(data, info), prefix))
> >
> > @@ -1111,7 +1135,7 @@ def _def_struct_type(self, expr: QAPIExpression):
> >          info = expr.info
> >          ifcond = QAPISchemaIfCond(expr.get('if'))
> >          features = self._make_features(expr.get('features'), info)
> > -        self._def_entity(QAPISchemaObjectType(
> > +        self._def_definition(QAPISchemaObjectType(
> >              name, info, expr.doc, ifcond, features, base,
> >              self._make_members(data, info),
> >              None))
> > @@ -1141,7 +1165,7 @@ def _def_union_type(self, expr: QAPIExpression):
> >                                 info)
> >              for (key, value) in data.items()]
> >          members: List[QAPISchemaObjectTypeMember] = []
> > -        self._def_entity(
> > +        self._def_definition(
> >              QAPISchemaObjectType(name, info, expr.doc, ifcond, features,
> >                                   base, members,
> >                                   QAPISchemaVariants(
> > @@ -1160,7 +1184,7 @@ def _def_alternate_type(self, expr: QAPIExpression):
> >                                 info)
> >              for (key, value) in data.items()]
> >          tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
> > -        self._def_entity(
> > +        self._def_definition(
> >              QAPISchemaAlternateType(
> >                  name, info, expr.doc, ifcond, features,
> >                  QAPISchemaVariants(None, info, tag_member, variants)))
> > @@ -1185,11 +1209,10 @@ def _def_command(self, expr: QAPIExpression):
> >          if isinstance(rets, list):
> >              assert len(rets) == 1
> >              rets = self._make_array_type(rets[0], info)
> > -        self._def_entity(QAPISchemaCommand(name, info, expr.doc, ifcond,
> > -                                           features, data, rets,
> > -                                           gen, success_response,
> > -                                           boxed, allow_oob, allow_preconfig,
> > -                                           coroutine))
> > +        self._def_definition(
> > +            QAPISchemaCommand(name, info, expr.doc, ifcond, features, data,
> > +                              rets, gen, success_response, boxed, allow_oob,
> > +                              allow_preconfig, coroutine))
> >
> >      def _def_event(self, expr: QAPIExpression):
> >          name = expr['event']
> > @@ -1202,8 +1225,8 @@ def _def_event(self, expr: QAPIExpression):
> >              data = self._make_implicit_object_type(
> >                  name, info, ifcond,
> >                  'arg', self._make_members(data, info))
> > -        self._def_entity(QAPISchemaEvent(name, info, expr.doc, ifcond,
> > -                                         features, data, boxed))
> > +        self._def_definition(QAPISchemaEvent(name, info, expr.doc, ifcond,
> > +                                             features, data, boxed))
> >
> >      def _def_exprs(self, exprs):
> >          for expr in exprs:
>
> Slightly more code, but with slightly fewer conditionals.  Feels a bit
> cleaner.
>

Probably a few more asserts and things that can come out, too. It's
nicer for static types at the expense of more OO boilerplate.
Re: [PATCH v2 03/19] qapi: create QAPISchemaDefinition
Posted by Markus Armbruster 10 months ago
John Snow <jsnow@redhat.com> writes:

> On Mon, Jan 15, 2024 at 8:16 AM Markus Armbruster <armbru@redhat.com> wrote:
>>
>> John Snow <jsnow@redhat.com> writes:
>>
>> > Include entities don't have names, but we generally expect "entities" to
>> > have names. Reclassify all entities with names as *definitions*, leaving
>> > the nameless include entities as QAPISchemaEntity instances.
>> >
>> > This is primarily to help simplify typing around expectations of what
>> > callers expect for properties of an "entity".
>> >
>> > Suggested-by: Markus Armbruster <armbru@redhat.com>
>> > Signed-off-by: John Snow <jsnow@redhat.com>
>> > ---
>> >  scripts/qapi/schema.py | 117 ++++++++++++++++++++++++-----------------
>> >  1 file changed, 70 insertions(+), 47 deletions(-)
>> >
>> > diff --git a/scripts/qapi/schema.py b/scripts/qapi/schema.py
>> > index b7830672e57..e39ed972a80 100644
>> > --- a/scripts/qapi/schema.py
>> > +++ b/scripts/qapi/schema.py
>> > @@ -55,14 +55,14 @@ def is_present(self):
>> >
>> >
>> >  class QAPISchemaEntity:
>> > -    meta: Optional[str] = None
>> > +    """
>> > +    QAPISchemaEntity represents all schema entities.
>> >
>> > -    def __init__(self, name: str, info, doc, ifcond=None, features=None):
>> > -        assert name is None or isinstance(name, str)
>> > -        for f in features or []:
>> > -            assert isinstance(f, QAPISchemaFeature)
>> > -            f.set_defined_in(name)
>> > -        self.name = name
>> > +    Notably, this includes both named and un-named entities, such as
>> > +    include directives. Entities with names are represented by the
>> > +    more specific sub-class `QAPISchemaDefinition` instead.
>> > +    """
>>
>> Hmm.  What about:
>>
>>        """
>>        A schema entity.
>>
>>        This is either a directive, such as include, or a definition.
>>        The latter use sub-class `QAPISchemaDefinition`.

Or is it "uses"?  Not a native speaker...

>>        """
>>
>
> Sure. Key point was just the cookie crumb to the sub-class.
>
>> > +    def __init__(self, info):
>> >          self._module = None
>> >          # For explicitly defined entities, info points to the (explicit)
>> >          # definition.  For builtins (and their arrays), info is None.
>> > @@ -70,14 +70,50 @@ def __init__(self, name: str, info, doc, ifcond=None, features=None):
>> >          # triggered the implicit definition (there may be more than one
>> >          # such place).
>> >          self.info = info
>> > +        self._checked = False
>> > +
>> > +    def __repr__(self):
>> > +        return "<%s at 0x%x>" % (type(self).__name__, id(self))
>> > +
>> > +    def check(self, schema):
>> > +        # pylint: disable=unused-argument
>> > +        self._checked = True
>> > +
>> > +    def connect_doc(self, doc=None):
>> > +        pass
>> > +
>> > +    def check_doc(self):
>> > +        pass
>> > +
>> > +    def _set_module(self, schema, info):
>> > +        assert self._checked
>> > +        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
>> > +        self._module = schema.module_by_fname(fname)
>> > +        self._module.add_entity(self)
>> > +
>> > +    def set_module(self, schema):
>> > +        self._set_module(schema, self.info)
>> > +
>> > +    def visit(self, visitor):
>> > +        # pylint: disable=unused-argument
>> > +        assert self._checked
>> > +
>> > +
>> > +class QAPISchemaDefinition(QAPISchemaEntity):
>> > +    meta: Optional[str] = None
>> > +
>> > +    def __init__(self, name: str, info, doc, ifcond=None, features=None):
>> > +        assert isinstance(name, str)
>> > +        super().__init__(info)
>> > +        for f in features or []:
>> > +            assert isinstance(f, QAPISchemaFeature)
>> > +            f.set_defined_in(name)
>> > +        self.name = name
>> >          self.doc = doc
>> >          self._ifcond = ifcond or QAPISchemaIfCond()
>> >          self.features = features or []
>> > -        self._checked = False
>> >
>> >      def __repr__(self):
>> > -        if self.name is None:
>> > -            return "<%s at 0x%x>" % (type(self).__name__, id(self))
>> >          return "<%s:%s at 0x%x>" % (type(self).__name__, self.name,
>> >                                      id(self))
>> >
>> > @@ -102,15 +138,6 @@ def check_doc(self):
>>        def check(self, schema):
>>            # pylint: disable=unused-argument
>>            assert not self._checked
>>            seen = {}
>>            for f in self.features:
>>                f.check_clash(self.info, seen)
>>            self._checked = True
>>
>>        def connect_doc(self, doc=None):
>>            doc = doc or self.doc
>>            if doc:
>>                for f in self.features:
>>                    doc.connect_feature(f)
>>
>>        def check_doc(self):
>> >          if self.doc:
>> >              self.doc.check()
>>
>> No super().FOO()?
>
> Ah, just an oversight. It worked out because the super method doesn't
> do anything anyway. check() and connect_doc() should also use the
> super call, probably.

Yes, please; it's a good habit.

>> >
>> > -    def _set_module(self, schema, info):
>> > -        assert self._checked
>> > -        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
>> > -        self._module = schema.module_by_fname(fname)
>> > -        self._module.add_entity(self)
>> > -
>> > -    def set_module(self, schema):
>> > -        self._set_module(schema, self.info)
>> > -
>> >      @property
>> >      def ifcond(self):
>> >          assert self._checked
>> > @@ -119,10 +146,6 @@ def ifcond(self):
>> >      def is_implicit(self):
>> >          return not self.info
>> >
>> > -    def visit(self, visitor):
>> > -        # pylint: disable=unused-argument
>> > -        assert self._checked
>> > -
>> >      def describe(self):
>> >          assert self.meta
>> >          return "%s '%s'" % (self.meta, self.name)
>> > @@ -222,7 +245,7 @@ def visit(self, visitor):
>> >
>> >  class QAPISchemaInclude(QAPISchemaEntity):
>> >      def __init__(self, sub_module, info):
>> > -        super().__init__(None, info, None)
>> > +        super().__init__(info)
>> >          self._sub_module = sub_module
>> >
>> >      def visit(self, visitor):
>> > @@ -230,7 +253,7 @@ def visit(self, visitor):
>> >          visitor.visit_include(self._sub_module.name, self.info)
>> >
>> >
>> > -class QAPISchemaType(QAPISchemaEntity):
>> > +class QAPISchemaType(QAPISchemaDefinition):
>> >      # Return the C type for common use.
>> >      # For the types we commonly box, this is a pointer type.
>> >      def c_type(self):
>> > @@ -801,7 +824,7 @@ def __init__(self, name, info, typ, ifcond=None):
>> >          super().__init__(name, info, typ, False, ifcond)
>> >
>> >
>> > -class QAPISchemaCommand(QAPISchemaEntity):
>> > +class QAPISchemaCommand(QAPISchemaDefinition):
>> >      meta = 'command'
>> >
>> >      def __init__(self, name, info, doc, ifcond, features,
>> > @@ -872,7 +895,7 @@ def visit(self, visitor):
>> >              self.coroutine)
>> >
>> >
>> > -class QAPISchemaEvent(QAPISchemaEntity):
>> > +class QAPISchemaEvent(QAPISchemaDefinition):
>> >      meta = 'event'
>> >
>> >      def __init__(self, name, info, doc, ifcond, features, arg_type, boxed):
>> > @@ -943,11 +966,12 @@ def __init__(self, fname):
>> >          self.check()
>> >
>> >      def _def_entity(self, ent):
>> > +        self._entity_list.append(ent)
>> > +
>> > +    def _def_definition(self, ent):
>>
>> Name the argument @defn instead of @ent?
>
> OK. (Was aiming for less diffstat, but yes.)

Yes, the churn from the rename is annoying.  More annoying than the now
odd name?  Not sure.

>> >          # Only the predefined types are allowed to not have info
>> >          assert ent.info or self._predefining
>> > -        self._entity_list.append(ent)
>> > -        if ent.name is None:
>> > -            return
>> > +        self._def_entity(ent)
>> >          # TODO reject names that differ only in '_' vs. '.'  vs. '-',
>> >          # because they're liable to clash in generated C.
>> >          other_ent = self._entity_dict.get(ent.name)
>> > @@ -1001,7 +1025,7 @@ def _def_include(self, expr: QAPIExpression):
>> >              QAPISchemaInclude(self._make_module(include), expr.info))
>> >
>> >      def _def_builtin_type(self, name, json_type, c_type):
>> > -        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
>> > +        self._def_definition(QAPISchemaBuiltinType(name, json_type, c_type))
>> >          # Instantiating only the arrays that are actually used would
>> >          # be nice, but we can't as long as their generated code
>> >          # (qapi-builtin-types.[ch]) may be shared by some other
>> > @@ -1027,15 +1051,15 @@ def _def_predefineds(self):
>> >              self._def_builtin_type(*t)
>> >          self.the_empty_object_type = QAPISchemaObjectType(
>> >              'q_empty', None, None, None, None, None, [], None)
>> > -        self._def_entity(self.the_empty_object_type)
>> > +        self._def_definition(self.the_empty_object_type)
>> >
>> >          qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
>> >                    'qbool']
>> >          qtype_values = self._make_enum_members(
>> >              [{'name': n} for n in qtypes], None)
>> >
>> > -        self._def_entity(QAPISchemaEnumType('QType', None, None, None, None,
>> > -                                            qtype_values, 'QTYPE'))
>> > +        self._def_definition(QAPISchemaEnumType('QType', None, None, None,
>> > +                                                None, qtype_values, 'QTYPE'))
>>
>> The long identifiers squeeze the (also long) argument list against the
>> right margin.  What about:
>>
>>            self._def_definition(QAPISchemaEnumType(
>>                'QType', None, None, None, None, qtype_values, 'QTYPE'))
>
> This is fine to my eyes.
>
>>
>> or
>>
>>            self._def_definition(
>>                QAPISchemaEnumType('QType', None, None, None, None,
>>                                   qtype_values, 'QTYPE'))
>>
>> We already use the former style elsewhere, visible below.
>>
>> You add one in the latter style in the second to last hunk.
>>
>> Pick one style and stick ot it?
>
> Yeah. I might try to run the black formatter in the end and just stick
> to that, if you don't mind a bit of churn in exchange for having it be
> a bit more mindless. It would be a big hassle to run it at the
> beginning of the series now, though... but I'll fix this instance for
> now.

I gave black a quick try a few months ago: the churn is massive.
Not sure it's worth it.

>> >      def _make_features(self, features, info):
>> >          if features is None:
>> > @@ -1057,7 +1081,7 @@ def _make_enum_members(self, values, info):
>> >      def _make_array_type(self, element_type, info):
>> >          name = element_type + 'List'    # reserved by check_defn_name_str()
>> >          if not self.lookup_type(name):
>> > -            self._def_entity(QAPISchemaArrayType(name, info, element_type))
>> > +            self._def_definition(QAPISchemaArrayType(name, info, element_type))
>>
>>                self._def_definition(QAPISchemaArrayType(
>>                    name, info, element_type))
>>
>> or
>>
>>                self._def_definition(
>>                    QAPISchemaArrayType(name, info, element_type))
>>
>
> OK. (79 columns too long for ya?)

I generally aim for 70, accept 75 without thought, and longer when the
alternative looks worse.  Deeply indented lines get a bit of extra
leeway.

>> >          return name
>> >
>> >      def _make_implicit_object_type(self, name, info, ifcond, role, members):
>> > @@ -1072,7 +1096,7 @@ def _make_implicit_object_type(self, name, info, ifcond, role, members):
>> >              # later.
>> >              pass
>> >          else:
>> > -            self._def_entity(QAPISchemaObjectType(
>> > +            self._def_definition(QAPISchemaObjectType(
>> >                  name, info, None, ifcond, None, None, members, None))
>> >          return name
>> >
>> > @@ -1083,7 +1107,7 @@ def _def_enum_type(self, expr: QAPIExpression):
>> >          ifcond = QAPISchemaIfCond(expr.get('if'))
>> >          info = expr.info
>> >          features = self._make_features(expr.get('features'), info)
>> > -        self._def_entity(QAPISchemaEnumType(
>> > +        self._def_definition(QAPISchemaEnumType(
>> >              name, info, expr.doc, ifcond, features,
>> >              self._make_enum_members(data, info), prefix))
>> >
>> > @@ -1111,7 +1135,7 @@ def _def_struct_type(self, expr: QAPIExpression):
>> >          info = expr.info
>> >          ifcond = QAPISchemaIfCond(expr.get('if'))
>> >          features = self._make_features(expr.get('features'), info)
>> > -        self._def_entity(QAPISchemaObjectType(
>> > +        self._def_definition(QAPISchemaObjectType(
>> >              name, info, expr.doc, ifcond, features, base,
>> >              self._make_members(data, info),
>> >              None))
>> > @@ -1141,7 +1165,7 @@ def _def_union_type(self, expr: QAPIExpression):
>> >                                 info)
>> >              for (key, value) in data.items()]
>> >          members: List[QAPISchemaObjectTypeMember] = []
>> > -        self._def_entity(
>> > +        self._def_definition(
>> >              QAPISchemaObjectType(name, info, expr.doc, ifcond, features,
>> >                                   base, members,
>> >                                   QAPISchemaVariants(
>> > @@ -1160,7 +1184,7 @@ def _def_alternate_type(self, expr: QAPIExpression):
>> >                                 info)
>> >              for (key, value) in data.items()]
>> >          tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
>> > -        self._def_entity(
>> > +        self._def_definition(
>> >              QAPISchemaAlternateType(
>> >                  name, info, expr.doc, ifcond, features,
>> >                  QAPISchemaVariants(None, info, tag_member, variants)))
>> > @@ -1185,11 +1209,10 @@ def _def_command(self, expr: QAPIExpression):
>> >          if isinstance(rets, list):
>> >              assert len(rets) == 1
>> >              rets = self._make_array_type(rets[0], info)
>> > -        self._def_entity(QAPISchemaCommand(name, info, expr.doc, ifcond,
>> > -                                           features, data, rets,
>> > -                                           gen, success_response,
>> > -                                           boxed, allow_oob, allow_preconfig,
>> > -                                           coroutine))
>> > +        self._def_definition(
>> > +            QAPISchemaCommand(name, info, expr.doc, ifcond, features, data,
>> > +                              rets, gen, success_response, boxed, allow_oob,
>> > +                              allow_preconfig, coroutine))
>> >
>> >      def _def_event(self, expr: QAPIExpression):
>> >          name = expr['event']
>> > @@ -1202,8 +1225,8 @@ def _def_event(self, expr: QAPIExpression):
>> >              data = self._make_implicit_object_type(
>> >                  name, info, ifcond,
>> >                  'arg', self._make_members(data, info))
>> > -        self._def_entity(QAPISchemaEvent(name, info, expr.doc, ifcond,
>> > -                                         features, data, boxed))
>> > +        self._def_definition(QAPISchemaEvent(name, info, expr.doc, ifcond,
>> > +                                             features, data, boxed))
>> >
>> >      def _def_exprs(self, exprs):
>> >          for expr in exprs:
>>
>> Slightly more code, but with slightly fewer conditionals.  Feels a bit
>> cleaner.
>>
>
> Probably a few more asserts and things that can come out, too. It's
> nicer for static types at the expense of more OO boilerplate.

Let's do it.
Re: [PATCH v2 03/19] qapi: create QAPISchemaDefinition
Posted by John Snow 10 months ago
On Tue, Jan 16, 2024 at 2:22 AM Markus Armbruster <armbru@redhat.com> wrote:
>
> John Snow <jsnow@redhat.com> writes:
>
> > On Mon, Jan 15, 2024 at 8:16 AM Markus Armbruster <armbru@redhat.com> wrote:
> >>
> >> John Snow <jsnow@redhat.com> writes:
> >>
> >> > Include entities don't have names, but we generally expect "entities" to
> >> > have names. Reclassify all entities with names as *definitions*, leaving
> >> > the nameless include entities as QAPISchemaEntity instances.
> >> >
> >> > This is primarily to help simplify typing around expectations of what
> >> > callers expect for properties of an "entity".
> >> >
> >> > Suggested-by: Markus Armbruster <armbru@redhat.com>
> >> > Signed-off-by: John Snow <jsnow@redhat.com>
> >> > ---
> >> >  scripts/qapi/schema.py | 117 ++++++++++++++++++++++++-----------------
> >> >  1 file changed, 70 insertions(+), 47 deletions(-)
> >> >
> >> > diff --git a/scripts/qapi/schema.py b/scripts/qapi/schema.py
> >> > index b7830672e57..e39ed972a80 100644
> >> > --- a/scripts/qapi/schema.py
> >> > +++ b/scripts/qapi/schema.py
> >> > @@ -55,14 +55,14 @@ def is_present(self):
> >> >
> >> >
> >> >  class QAPISchemaEntity:
> >> > -    meta: Optional[str] = None
> >> > +    """
> >> > +    QAPISchemaEntity represents all schema entities.
> >> >
> >> > -    def __init__(self, name: str, info, doc, ifcond=None, features=None):
> >> > -        assert name is None or isinstance(name, str)
> >> > -        for f in features or []:
> >> > -            assert isinstance(f, QAPISchemaFeature)
> >> > -            f.set_defined_in(name)
> >> > -        self.name = name
> >> > +    Notably, this includes both named and un-named entities, such as
> >> > +    include directives. Entities with names are represented by the
> >> > +    more specific sub-class `QAPISchemaDefinition` instead.
> >> > +    """
> >>
> >> Hmm.  What about:
> >>
> >>        """
> >>        A schema entity.
> >>
> >>        This is either a directive, such as include, or a definition.
> >>        The latter use sub-class `QAPISchemaDefinition`.
>
> Or is it "uses"?  Not a native speaker...

American English: collective nouns are treated as singular ("Congress
has passed a law")
British English: collective nouns are treated as plural ("Parliament
have enacted a new regulation")

>
> >>        """
> >>
> >
> > Sure. Key point was just the cookie crumb to the sub-class.
> >
> >> > +    def __init__(self, info):
> >> >          self._module = None
> >> >          # For explicitly defined entities, info points to the (explicit)
> >> >          # definition.  For builtins (and their arrays), info is None.
> >> > @@ -70,14 +70,50 @@ def __init__(self, name: str, info, doc, ifcond=None, features=None):
> >> >          # triggered the implicit definition (there may be more than one
> >> >          # such place).
> >> >          self.info = info
> >> > +        self._checked = False
> >> > +
> >> > +    def __repr__(self):
> >> > +        return "<%s at 0x%x>" % (type(self).__name__, id(self))
> >> > +
> >> > +    def check(self, schema):
> >> > +        # pylint: disable=unused-argument
> >> > +        self._checked = True
> >> > +
> >> > +    def connect_doc(self, doc=None):
> >> > +        pass
> >> > +
> >> > +    def check_doc(self):
> >> > +        pass
> >> > +
> >> > +    def _set_module(self, schema, info):
> >> > +        assert self._checked
> >> > +        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
> >> > +        self._module = schema.module_by_fname(fname)
> >> > +        self._module.add_entity(self)
> >> > +
> >> > +    def set_module(self, schema):
> >> > +        self._set_module(schema, self.info)
> >> > +
> >> > +    def visit(self, visitor):
> >> > +        # pylint: disable=unused-argument
> >> > +        assert self._checked
> >> > +
> >> > +
> >> > +class QAPISchemaDefinition(QAPISchemaEntity):
> >> > +    meta: Optional[str] = None
> >> > +
> >> > +    def __init__(self, name: str, info, doc, ifcond=None, features=None):
> >> > +        assert isinstance(name, str)
> >> > +        super().__init__(info)
> >> > +        for f in features or []:
> >> > +            assert isinstance(f, QAPISchemaFeature)
> >> > +            f.set_defined_in(name)
> >> > +        self.name = name
> >> >          self.doc = doc
> >> >          self._ifcond = ifcond or QAPISchemaIfCond()
> >> >          self.features = features or []
> >> > -        self._checked = False
> >> >
> >> >      def __repr__(self):
> >> > -        if self.name is None:
> >> > -            return "<%s at 0x%x>" % (type(self).__name__, id(self))
> >> >          return "<%s:%s at 0x%x>" % (type(self).__name__, self.name,
> >> >                                      id(self))
> >> >
> >> > @@ -102,15 +138,6 @@ def check_doc(self):
> >>        def check(self, schema):
> >>            # pylint: disable=unused-argument
> >>            assert not self._checked
> >>            seen = {}
> >>            for f in self.features:
> >>                f.check_clash(self.info, seen)
> >>            self._checked = True
> >>
> >>        def connect_doc(self, doc=None):
> >>            doc = doc or self.doc
> >>            if doc:
> >>                for f in self.features:
> >>                    doc.connect_feature(f)
> >>
> >>        def check_doc(self):
> >> >          if self.doc:
> >> >              self.doc.check()
> >>
> >> No super().FOO()?
> >
> > Ah, just an oversight. It worked out because the super method doesn't
> > do anything anyway. check() and connect_doc() should also use the
> > super call, probably.
>
> Yes, please; it's a good habit.
>
> >> >
> >> > -    def _set_module(self, schema, info):
> >> > -        assert self._checked
> >> > -        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
> >> > -        self._module = schema.module_by_fname(fname)
> >> > -        self._module.add_entity(self)
> >> > -
> >> > -    def set_module(self, schema):
> >> > -        self._set_module(schema, self.info)
> >> > -
> >> >      @property
> >> >      def ifcond(self):
> >> >          assert self._checked
> >> > @@ -119,10 +146,6 @@ def ifcond(self):
> >> >      def is_implicit(self):
> >> >          return not self.info
> >> >
> >> > -    def visit(self, visitor):
> >> > -        # pylint: disable=unused-argument
> >> > -        assert self._checked
> >> > -
> >> >      def describe(self):
> >> >          assert self.meta
> >> >          return "%s '%s'" % (self.meta, self.name)
> >> > @@ -222,7 +245,7 @@ def visit(self, visitor):
> >> >
> >> >  class QAPISchemaInclude(QAPISchemaEntity):
> >> >      def __init__(self, sub_module, info):
> >> > -        super().__init__(None, info, None)
> >> > +        super().__init__(info)
> >> >          self._sub_module = sub_module
> >> >
> >> >      def visit(self, visitor):
> >> > @@ -230,7 +253,7 @@ def visit(self, visitor):
> >> >          visitor.visit_include(self._sub_module.name, self.info)
> >> >
> >> >
> >> > -class QAPISchemaType(QAPISchemaEntity):
> >> > +class QAPISchemaType(QAPISchemaDefinition):
> >> >      # Return the C type for common use.
> >> >      # For the types we commonly box, this is a pointer type.
> >> >      def c_type(self):
> >> > @@ -801,7 +824,7 @@ def __init__(self, name, info, typ, ifcond=None):
> >> >          super().__init__(name, info, typ, False, ifcond)
> >> >
> >> >
> >> > -class QAPISchemaCommand(QAPISchemaEntity):
> >> > +class QAPISchemaCommand(QAPISchemaDefinition):
> >> >      meta = 'command'
> >> >
> >> >      def __init__(self, name, info, doc, ifcond, features,
> >> > @@ -872,7 +895,7 @@ def visit(self, visitor):
> >> >              self.coroutine)
> >> >
> >> >
> >> > -class QAPISchemaEvent(QAPISchemaEntity):
> >> > +class QAPISchemaEvent(QAPISchemaDefinition):
> >> >      meta = 'event'
> >> >
> >> >      def __init__(self, name, info, doc, ifcond, features, arg_type, boxed):
> >> > @@ -943,11 +966,12 @@ def __init__(self, fname):
> >> >          self.check()
> >> >
> >> >      def _def_entity(self, ent):
> >> > +        self._entity_list.append(ent)
> >> > +
> >> > +    def _def_definition(self, ent):
> >>
> >> Name the argument @defn instead of @ent?
> >
> > OK. (Was aiming for less diffstat, but yes.)
>
> Yes, the churn from the rename is annoying.  More annoying than the now
> odd name?  Not sure.
>
> >> >          # Only the predefined types are allowed to not have info
> >> >          assert ent.info or self._predefining
> >> > -        self._entity_list.append(ent)
> >> > -        if ent.name is None:
> >> > -            return
> >> > +        self._def_entity(ent)
> >> >          # TODO reject names that differ only in '_' vs. '.'  vs. '-',
> >> >          # because they're liable to clash in generated C.
> >> >          other_ent = self._entity_dict.get(ent.name)
> >> > @@ -1001,7 +1025,7 @@ def _def_include(self, expr: QAPIExpression):
> >> >              QAPISchemaInclude(self._make_module(include), expr.info))
> >> >
> >> >      def _def_builtin_type(self, name, json_type, c_type):
> >> > -        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
> >> > +        self._def_definition(QAPISchemaBuiltinType(name, json_type, c_type))
> >> >          # Instantiating only the arrays that are actually used would
> >> >          # be nice, but we can't as long as their generated code
> >> >          # (qapi-builtin-types.[ch]) may be shared by some other
> >> > @@ -1027,15 +1051,15 @@ def _def_predefineds(self):
> >> >              self._def_builtin_type(*t)
> >> >          self.the_empty_object_type = QAPISchemaObjectType(
> >> >              'q_empty', None, None, None, None, None, [], None)
> >> > -        self._def_entity(self.the_empty_object_type)
> >> > +        self._def_definition(self.the_empty_object_type)
> >> >
> >> >          qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
> >> >                    'qbool']
> >> >          qtype_values = self._make_enum_members(
> >> >              [{'name': n} for n in qtypes], None)
> >> >
> >> > -        self._def_entity(QAPISchemaEnumType('QType', None, None, None, None,
> >> > -                                            qtype_values, 'QTYPE'))
> >> > +        self._def_definition(QAPISchemaEnumType('QType', None, None, None,
> >> > +                                                None, qtype_values, 'QTYPE'))
> >>
> >> The long identifiers squeeze the (also long) argument list against the
> >> right margin.  What about:
> >>
> >>            self._def_definition(QAPISchemaEnumType(
> >>                'QType', None, None, None, None, qtype_values, 'QTYPE'))
> >
> > This is fine to my eyes.
> >
> >>
> >> or
> >>
> >>            self._def_definition(
> >>                QAPISchemaEnumType('QType', None, None, None, None,
> >>                                   qtype_values, 'QTYPE'))
> >>
> >> We already use the former style elsewhere, visible below.
> >>
> >> You add one in the latter style in the second to last hunk.
> >>
> >> Pick one style and stick ot it?
> >
> > Yeah. I might try to run the black formatter in the end and just stick
> > to that, if you don't mind a bit of churn in exchange for having it be
> > a bit more mindless. It would be a big hassle to run it at the
> > beginning of the series now, though... but I'll fix this instance for
> > now.
>
> I gave black a quick try a few months ago: the churn is massive.
> Not sure it's worth it.
>

You can reduce the churn:

black --line-length=79 --skip-string-normalization schema.py

It still churns a lot, but it's a lot less. I like not having to think
about the formatting, but we can worry about that after this series.

> >> >      def _make_features(self, features, info):
> >> >          if features is None:
> >> > @@ -1057,7 +1081,7 @@ def _make_enum_members(self, values, info):
> >> >      def _make_array_type(self, element_type, info):
> >> >          name = element_type + 'List'    # reserved by check_defn_name_str()
> >> >          if not self.lookup_type(name):
> >> > -            self._def_entity(QAPISchemaArrayType(name, info, element_type))
> >> > +            self._def_definition(QAPISchemaArrayType(name, info, element_type))
> >>
> >>                self._def_definition(QAPISchemaArrayType(
> >>                    name, info, element_type))
> >>
> >> or
> >>
> >>                self._def_definition(
> >>                    QAPISchemaArrayType(name, info, element_type))
> >>
> >
> > OK. (79 columns too long for ya?)
>
> I generally aim for 70, accept 75 without thought, and longer when the
> alternative looks worse.  Deeply indented lines get a bit of extra
> leeway.
>
> >> >          return name
> >> >
> >> >      def _make_implicit_object_type(self, name, info, ifcond, role, members):
> >> > @@ -1072,7 +1096,7 @@ def _make_implicit_object_type(self, name, info, ifcond, role, members):
> >> >              # later.
> >> >              pass
> >> >          else:
> >> > -            self._def_entity(QAPISchemaObjectType(
> >> > +            self._def_definition(QAPISchemaObjectType(
> >> >                  name, info, None, ifcond, None, None, members, None))
> >> >          return name
> >> >
> >> > @@ -1083,7 +1107,7 @@ def _def_enum_type(self, expr: QAPIExpression):
> >> >          ifcond = QAPISchemaIfCond(expr.get('if'))
> >> >          info = expr.info
> >> >          features = self._make_features(expr.get('features'), info)
> >> > -        self._def_entity(QAPISchemaEnumType(
> >> > +        self._def_definition(QAPISchemaEnumType(
> >> >              name, info, expr.doc, ifcond, features,
> >> >              self._make_enum_members(data, info), prefix))
> >> >
> >> > @@ -1111,7 +1135,7 @@ def _def_struct_type(self, expr: QAPIExpression):
> >> >          info = expr.info
> >> >          ifcond = QAPISchemaIfCond(expr.get('if'))
> >> >          features = self._make_features(expr.get('features'), info)
> >> > -        self._def_entity(QAPISchemaObjectType(
> >> > +        self._def_definition(QAPISchemaObjectType(
> >> >              name, info, expr.doc, ifcond, features, base,
> >> >              self._make_members(data, info),
> >> >              None))
> >> > @@ -1141,7 +1165,7 @@ def _def_union_type(self, expr: QAPIExpression):
> >> >                                 info)
> >> >              for (key, value) in data.items()]
> >> >          members: List[QAPISchemaObjectTypeMember] = []
> >> > -        self._def_entity(
> >> > +        self._def_definition(
> >> >              QAPISchemaObjectType(name, info, expr.doc, ifcond, features,
> >> >                                   base, members,
> >> >                                   QAPISchemaVariants(
> >> > @@ -1160,7 +1184,7 @@ def _def_alternate_type(self, expr: QAPIExpression):
> >> >                                 info)
> >> >              for (key, value) in data.items()]
> >> >          tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
> >> > -        self._def_entity(
> >> > +        self._def_definition(
> >> >              QAPISchemaAlternateType(
> >> >                  name, info, expr.doc, ifcond, features,
> >> >                  QAPISchemaVariants(None, info, tag_member, variants)))
> >> > @@ -1185,11 +1209,10 @@ def _def_command(self, expr: QAPIExpression):
> >> >          if isinstance(rets, list):
> >> >              assert len(rets) == 1
> >> >              rets = self._make_array_type(rets[0], info)
> >> > -        self._def_entity(QAPISchemaCommand(name, info, expr.doc, ifcond,
> >> > -                                           features, data, rets,
> >> > -                                           gen, success_response,
> >> > -                                           boxed, allow_oob, allow_preconfig,
> >> > -                                           coroutine))
> >> > +        self._def_definition(
> >> > +            QAPISchemaCommand(name, info, expr.doc, ifcond, features, data,
> >> > +                              rets, gen, success_response, boxed, allow_oob,
> >> > +                              allow_preconfig, coroutine))
> >> >
> >> >      def _def_event(self, expr: QAPIExpression):
> >> >          name = expr['event']
> >> > @@ -1202,8 +1225,8 @@ def _def_event(self, expr: QAPIExpression):
> >> >              data = self._make_implicit_object_type(
> >> >                  name, info, ifcond,
> >> >                  'arg', self._make_members(data, info))
> >> > -        self._def_entity(QAPISchemaEvent(name, info, expr.doc, ifcond,
> >> > -                                         features, data, boxed))
> >> > +        self._def_definition(QAPISchemaEvent(name, info, expr.doc, ifcond,
> >> > +                                             features, data, boxed))
> >> >
> >> >      def _def_exprs(self, exprs):
> >> >          for expr in exprs:
> >>
> >> Slightly more code, but with slightly fewer conditionals.  Feels a bit
> >> cleaner.
> >>
> >
> > Probably a few more asserts and things that can come out, too. It's
> > nicer for static types at the expense of more OO boilerplate.
>
> Let's do it.
>