qapi: add 'if' to union members

Add 'if' key to union members:

{ 'union': 'TestIfUnion', 'data':
    'mem': { 'type': 'str', 'if': 'COND'} }

The generated code remains unconditional for now. Later patches
generate the conditionals.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181213123724.4866-16-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

1 files changed, 8 insertions, 7 deletions

diff --git a/scripts/qapi/common.py b/scripts/qapi/common.py
index 98e9d6f..44fe886 100644
--- a/scripts/qapi/common.py
+++ b/scripts/qapi/common.py
@@ -803,7 +803,7 @@ def check_union(expr, info):
         check_name(info, "Member of union '%s'" % name, key)
 
         check_known_keys(info, "member '%s' of union '%s'" % (key, name),
-                         value, ['type'], [])
+                         value, ['type'], ['if'])
         # Each value must name a known type
         check_type(info, "Member '%s' of union '%s'" % (key, name),
                    value['type'],
@@ -1483,8 +1483,8 @@ class QAPISchemaObjectTypeVariants(object):
 class QAPISchemaObjectTypeVariant(QAPISchemaObjectTypeMember):
     role = 'branch'
 
-    def __init__(self, name, typ):
-        QAPISchemaObjectTypeMember.__init__(self, name, typ, False)
+    def __init__(self, name, typ, ifcond=None):
+        QAPISchemaObjectTypeMember.__init__(self, name, typ, False, ifcond)
 
 
 class QAPISchemaAlternateType(QAPISchemaType):
@@ -1757,14 +1757,14 @@ class QAPISchema(object):
     def _make_variant(self, case, typ):
         return QAPISchemaObjectTypeVariant(case, typ)
 
-    def _make_simple_variant(self, case, typ, info):
+    def _make_simple_variant(self, case, typ, ifcond, info):
         if isinstance(typ, list):
             assert len(typ) == 1
             typ = self._make_array_type(typ[0], info)
         typ = self._make_implicit_object_type(
             typ, info, None, self.lookup_type(typ),
             'wrapper', [self._make_member('data', typ, None, info)])
-        return QAPISchemaObjectTypeVariant(case, typ)
+        return QAPISchemaObjectTypeVariant(case, typ, ifcond)
 
     def _def_union_type(self, expr, info, doc):
         name = expr['union']
@@ -1782,9 +1782,10 @@ class QAPISchema(object):
                         for (key, value) in data.items()]
             members = []
         else:
-            variants = [self._make_simple_variant(key, value['type'], info)
+            variants = [self._make_simple_variant(key, value['type'],
+                                                  value.get('if'), info)
                         for (key, value) in data.items()]
-            enum = [{'name': v.name} for v in variants]
+            enum = [{'name': v.name, 'if': v.ifcond} for v in variants]
             typ = self._make_implicit_enum_type(name, info, ifcond, enum)
             tag_member = QAPISchemaObjectTypeMember('type', typ, False)
             members = [tag_member]