[Qemu-devel] [PATCH v7 04/14] qapi: Don't use info as witness of implicit object type

[Eric Blake]

A future patch will enable error reporting from the various
QAPISchema*.check() methods.  But to report an error related
to an implicit type, we'll need to associate a location with
the type (the same location as the top-level entity that is
causing the creation of the implicit type), and once we do
that, keying off of whether foo.info exists is no longer a
viable way to determine if foo is an implicit type.

Instead, add an is_implicit() method to QAPISchemaEntity, with
an internal helper overridden for ObjectType and EnumType, and
use that function where needed.

Signed-off-by: Eric Blake <address@hidden>

---
v7: declare at the Entity level, with an optional argument for
filtering by sub-class
v6: split 11/46 into pieces; don't rename _info yet; rework atop
nicer filtering mechanism, including no need to change visitor
signature
---
 scripts/qapi-types.py |  2 +-
 scripts/qapi-visit.py |  2 +-
 scripts/qapi.py       | 24 +++++++++++++++++++++---
 3 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/scripts/qapi-types.py b/scripts/qapi-types.py
index 2a29c6e..227ea5c 100644
--- a/scripts/qapi-types.py
+++ b/scripts/qapi-types.py
@@ -235,7 +235,7 @@ class QAPISchemaGenTypeVisitor(QAPISchemaVisitor):

     def visit_needed(self, entity):
         # Visit everything except implicit objects
-        return not isinstance(entity, QAPISchemaObjectType) or entity.info
+        return not entity.is_implicit(QAPISchemaObjectType)

     def _gen_type_cleanup(self, name):
         self.decl += gen_type_cleanup_decl(name)
diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py
index 9fc79a7..56b8390 100644
--- a/scripts/qapi-visit.py
+++ b/scripts/qapi-visit.py
@@ -335,7 +335,7 @@ class QAPISchemaGenVisitVisitor(QAPISchemaVisitor):

     def visit_needed(self, entity):
         # Visit everything except implicit objects
-        return not isinstance(entity, QAPISchemaObjectType) or entity.info
+        return not entity.is_implicit(QAPISchemaObjectType)

     def visit_enum_type(self, name, info, values, prefix):
         self.decl += gen_visit_decl(name, scalar=True)
diff --git a/scripts/qapi.py b/scripts/qapi.py
index 4573599..19cc78e 100644
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -801,6 +801,16 @@ class QAPISchemaEntity(object):
     def check(self, schema):
         pass

+    # Return True if this entity is implicit
+    # If @typ, only return True if entity is also an instance of that type
+    def is_implicit(self, typ=None):
+        if typ and not isinstance(self, typ):
+            return False
+        return self._is_implicit()
+
+    def _is_implicit(self):
+        return not self.info
+
     def visit(self, visitor):
         pass

@@ -903,6 +913,10 @@ class QAPISchemaEnumType(QAPISchemaType):
     def check(self, schema):
         assert len(set(self.values)) == len(self.values)

+    def _is_implicit(self):
+        # See QAPISchema._make_implicit_enum_type()
+        return self.name[-4:] == 'Kind'
+
     def c_type(self, is_param=False):
         return c_name(self.name)

@@ -973,12 +987,16 @@ class QAPISchemaObjectType(QAPISchemaType):
             self.variants.check(schema, members, seen)
         self.members = members

+    def _is_implicit(self):
+        # See QAPISchema._make_implicit_object_type()
+        return self.name[0] == ':'
+
     def c_name(self):
-        assert self.info
+        assert not self.is_implicit()
         return QAPISchemaType.c_name(self)

     def c_type(self, is_param=False):
-        assert self.info
+        assert not self.is_implicit()
         return QAPISchemaType.c_type(self)

     def json_type(self):
@@ -1046,7 +1064,7 @@ class 
QAPISchemaObjectTypeVariant(QAPISchemaObjectTypeMember):
     # This function exists to support ugly simple union special cases
     # TODO get rid of them, and drop the function
     def simple_union_type(self):
-        if isinstance(self.type, QAPISchemaObjectType) and not self.type.info:
+        if self.type.is_implicit(QAPISchemaObjectType):
             assert len(self.type.members) == 1
             assert not self.type.variants
             return self.type.members[0].type
-- 
2.4.3