[Qemu-devel] [PATCH v6 09/16] qapi: Reuse code for flat union base validation

[Eric Blake <eblake@redhat.com>]

Rather than open-code the check for a valid base type, we
should reuse the common functionality. This allows for
consistent error messages, and also makes it easier for a
later patch to turn on support for inline anonymous base
structures.

Test flat-union-inline is updated to test only one feature
(anonymous branch dictionaries), which can be implemented
independently (test flat-union-bad-base already covers the
idea of an anonymous base dictionary).

Signed-off-by: Eric Blake <eblake@redhat.com>

---
v6: rebase to earlier testsuite improvements, wording tweak
---
 scripts/qapi.py                             | 11 +++++------
 tests/qapi-schema/flat-union-bad-base.err   |  2 +-
 tests/qapi-schema/flat-union-base-any.err   |  2 +-
 tests/qapi-schema/flat-union-base-union.err |  2 +-
 tests/qapi-schema/flat-union-cycle.err      |  2 +-
 tests/qapi-schema/flat-union-inline.err     |  2 +-
 tests/qapi-schema/flat-union-inline.json    |  4 ++--
 tests/qapi-schema/flat-union-no-base.err    |  2 +-
 tests/qapi-schema/union-invalid-base.err    |  2 +-
 9 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/scripts/qapi.py b/scripts/qapi.py
index ec450a6..4825e62 100644
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -560,15 +560,14 @@ def check_union(expr, expr_info):
     # Else, it's a flat union.
     else:
         # The object must have a string member 'base'.
-        if not isinstance(base, str):
+        check_type(expr_info, "'base' for union '%s'" % name,
+                   base, allow_metas=['struct'])
+        if not base:
             raise QAPIExprError(expr_info,
-                                "Flat union '%s' must have a string base field"
+                                "Flat union '%s' must have a base"
                                 % name)
         base_fields = find_base_fields(base)
-        if not base_fields:
-            raise QAPIExprError(expr_info,
-                                "Base '%s' is not a valid struct"
-                                % base)
+        assert base_fields

         # The value of member 'discriminator' must name a non-optional
         # member of the base struct.
diff --git a/tests/qapi-schema/flat-union-bad-base.err b/tests/qapi-schema/flat-union-bad-base.err
index f9c31b2..79b8a71 100644
--- a/tests/qapi-schema/flat-union-bad-base.err
+++ b/tests/qapi-schema/flat-union-bad-base.err
@@ -1 +1 @@
-tests/qapi-schema/flat-union-bad-base.json:9: Flat union 'TestUnion' must have a string base field
+tests/qapi-schema/flat-union-bad-base.json:9: 'base' for union 'TestUnion' should be a type name
diff --git a/tests/qapi-schema/flat-union-base-any.err b/tests/qapi-schema/flat-union-base-any.err
index ad4d629..646f1c9 100644
--- a/tests/qapi-schema/flat-union-base-any.err
+++ b/tests/qapi-schema/flat-union-base-any.err
@@ -1 +1 @@
-tests/qapi-schema/flat-union-base-any.json:8: Base 'any' is not a valid struct
+tests/qapi-schema/flat-union-base-any.json:8: 'base' for union 'TestUnion' cannot use built-in type 'any'
diff --git a/tests/qapi-schema/flat-union-base-union.err b/tests/qapi-schema/flat-union-base-union.err
index ede9859..d50e687 100644
--- a/tests/qapi-schema/flat-union-base-union.err
+++ b/tests/qapi-schema/flat-union-base-union.err
@@ -1 +1 @@
-tests/qapi-schema/flat-union-base-union.json:11: Base 'UnionBase' is not a valid struct
+tests/qapi-schema/flat-union-base-union.json:11: 'base' for union 'TestUnion' cannot use union type 'UnionBase'
diff --git a/tests/qapi-schema/flat-union-cycle.err b/tests/qapi-schema/flat-union-cycle.err
index d4f2a09..834d3f3 100644
--- a/tests/qapi-schema/flat-union-cycle.err
+++ b/tests/qapi-schema/flat-union-cycle.err
@@ -1 +1 @@
-tests/qapi-schema/flat-union-cycle.json:6: Base 'Union' is not a valid struct
+tests/qapi-schema/flat-union-cycle.json:6: 'base' for union 'Union' cannot use union type 'Union'
diff --git a/tests/qapi-schema/flat-union-inline.err b/tests/qapi-schema/flat-union-inline.err
index ec58627..2333358 100644
--- a/tests/qapi-schema/flat-union-inline.err
+++ b/tests/qapi-schema/flat-union-inline.err
@@ -1 +1 @@
-tests/qapi-schema/flat-union-inline.json:7: Flat union 'TestUnion' must have a string base field
+tests/qapi-schema/flat-union-inline.json:7: Member 'value1' of union 'TestUnion' should be a type name
diff --git a/tests/qapi-schema/flat-union-inline.json b/tests/qapi-schema/flat-union-inline.json
index 6bfdd65..62c7cda 100644
--- a/tests/qapi-schema/flat-union-inline.json
+++ b/tests/qapi-schema/flat-union-inline.json
@@ -1,11 +1,11 @@
 # we require branches to be a struct name
-# TODO: should we allow anonymous inline types?
+# TODO: should we allow anonymous inline branch types?
 { 'enum': 'TestEnum',
   'data': [ 'value1', 'value2' ] }
 { 'struct': 'Base',
   'data': { 'enum1': 'TestEnum', 'kind': 'str' } }
 { 'union': 'TestUnion',
-  'base': { 'enum1': 'TestEnum', 'kind': 'str' },
+  'base': 'Base',
   'discriminator': 'enum1',
   'data': { 'value1': { 'string': 'str' },
             'value2': { 'integer': 'int' } } }
diff --git a/tests/qapi-schema/flat-union-no-base.err b/tests/qapi-schema/flat-union-no-base.err
index bb3f708..841c93b 100644
--- a/tests/qapi-schema/flat-union-no-base.err
+++ b/tests/qapi-schema/flat-union-no-base.err
@@ -1 +1 @@
-tests/qapi-schema/flat-union-no-base.json:9: Flat union 'TestUnion' must have a string base field
+tests/qapi-schema/flat-union-no-base.json:9: Flat union 'TestUnion' must have a base
diff --git a/tests/qapi-schema/union-invalid-base.err b/tests/qapi-schema/union-invalid-base.err
index 9f63796..03d7b97 100644
--- a/tests/qapi-schema/union-invalid-base.err
+++ b/tests/qapi-schema/union-invalid-base.err
@@ -1 +1 @@
-tests/qapi-schema/union-invalid-base.json:8: Base 'int' is not a valid struct
+tests/qapi-schema/union-invalid-base.json:8: 'base' for union 'TestUnion' cannot use built-in type 'int'
-- 
2.4.3