tests/qapi-schema: Clean up positive test for conditionals

Union TestIfUnion is conditional on macros TEST_IF_UNION and
TEST_IF_STRUCT.  It uses TestIfEnum, which is conditional on macro
TEST_IF_ENUM.  If TEST_IF_UNION and TEST_IF_STRUCT are defined, but
TEST_IF_ENUM isn't, the generated code won't compile.

Command test-if-cmd is conditional an macros TEST_IF_CMD and
TEST_IF_STRUCT, and uses TestIfEnum.  Similar issue.

Event TEST_IF_EVENT is conditional an macros TEST_IF_EVT and
TEST_IF_STRUCT, and uses TestIfEnum.  Similar issue.

Replace the uses of TestIfEnum in the latter two by str.

TestIfUnion is now TestIfEnum's only user.  Change TestIfEnum's
condition to TEST_IF_UNION.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230316071325.492471-12-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Commit message corrected]

tests/qapi-schema/qapi-schema-test.json

@@ -225,7 +225,7 @@
 
 { 'enum': 'TestIfEnum',
   'data': [ 'foo', { 'name' : 'bar', 'if': 'TEST_IF_ENUM_MEMBER' } ],
-  'if': 'TEST_IF_ENUM' }
+  'if': 'TEST_IF_UNION' }
 
 { 'union': 'TestIfUnion',
   'base': { 'type': 'TestIfEnum' },
@@ -250,7 +250,7 @@
 { 'command': 'test-if-cmd',
   'data': {
     'foo': 'TestIfStruct',
-    'bar': { 'type': 'TestIfEnum', 'if': 'TEST_IF_CMD_ARG' } },
+    'bar': { 'type': 'str', 'if': 'TEST_IF_CMD_ARG' } },
   'returns': 'UserDefThree',
   'if': { 'all': ['TEST_IF_CMD', 'TEST_IF_STRUCT'] } }
 
@@ -258,7 +258,7 @@
 
 { 'event': 'TEST_IF_EVENT',
   'data': { 'foo': 'TestIfStruct',
-            'bar': { 'type': ['TestIfEnum'], 'if': 'TEST_IF_EVT_ARG' } },
+            'bar': { 'type': ['str'], 'if': 'TEST_IF_EVT_ARG' } },
   'if': { 'all': ['TEST_IF_EVT', 'TEST_IF_STRUCT'] } }
 
 { 'event': 'TEST_IF_EVENT2', 'data': {},

tests/qapi-schema/qapi-schema-test.out

@@ -252,7 +252,7 @@ enum TestIfEnum
     member foo
     member bar
         if TEST_IF_ENUM_MEMBER
-    if TEST_IF_ENUM
+    if TEST_IF_UNION
 object q_obj_TestIfUnion-base
     member type: TestIfEnum optional=False
     if {'all': ['TEST_IF_UNION', 'TEST_IF_STRUCT']}
@@ -283,7 +283,7 @@ command test-if-alternate-cmd q_obj_test-if-alternate-cmd-arg -> None
     if {'all': ['TEST_IF_ALT', 'TEST_IF_STRUCT']}
 object q_obj_test-if-cmd-arg
     member foo: TestIfStruct optional=False
-    member bar: TestIfEnum optional=False
+    member bar: str optional=False
         if TEST_IF_CMD_ARG
     if {'all': ['TEST_IF_CMD', 'TEST_IF_STRUCT']}
 command test-if-cmd q_obj_test-if-cmd-arg -> UserDefThree
@@ -291,11 +291,9 @@ command test-if-cmd q_obj_test-if-cmd-arg -> UserDefThree
     if {'all': ['TEST_IF_CMD', 'TEST_IF_STRUCT']}
 command test-cmd-return-def-three None -> UserDefThree
     gen=True success_response=True boxed=False oob=False preconfig=False
-array TestIfEnumList TestIfEnum
-    if TEST_IF_ENUM
 object q_obj_TEST_IF_EVENT-arg
     member foo: TestIfStruct optional=False
-    member bar: TestIfEnumList optional=False
+    member bar: strList optional=False
         if TEST_IF_EVT_ARG
     if {'all': ['TEST_IF_EVT', 'TEST_IF_STRUCT']}
 event TEST_IF_EVENT q_obj_TEST_IF_EVENT-arg