[v8,08/40] qapi: Add some union tests

diff --git a/tests/Makefile b/tests/Makefile
index 3865a61..3978c3d 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -217,10 +217,18 @@  check-qapi-schema-y := $(addprefix tests/qapi-schema/, \
 	qapi-schema-test.json quoted-structural-chars.json \
 	trailing-comma-list.json trailing-comma-object.json \
 	unclosed-list.json unclosed-object.json unclosed-string.json \
-	duplicate-key.json union-invalid-base.json flat-union-no-base.json \
-	flat-union-invalid-discriminator.json \
+	duplicate-key.json union-invalid-base.json union-bad-branch.json \
+	union-optional-branch.json union-unknown.json union-max.json \
+	flat-union-optional-discriminator.json flat-union-no-base.json \
+	flat-union-invalid-discriminator.json flat-union-inline.json \
 	flat-union-invalid-branch-key.json flat-union-reverse-define.json \
-	flat-union-string-discriminator.json \
+	flat-union-string-discriminator.json union-base-no-discriminator.json \
+	flat-union-bad-discriminator.json flat-union-bad-base.json \
+	flat-union-base-star.json flat-union-int-branch.json \
+	flat-union-base-union.json flat-union-branch-clash.json \
+	alternate-nested.json alternate-unknown.json alternate-clash.json \
+	alternate-good.json alternate-base.json alternate-array.json \
+	alternate-conflict-string.json alternate-conflict-dict.json \
 	include-simple.json include-relpath.json include-format-err.json \
 	include-non-file.json include-no-file.json include-before-err.json \
 	include-nested-err.json include-self-cycle.json include-cycle.json \
diff --git a/tests/qapi-schema/alternate-array.err b/tests/qapi-schema/alternate-array.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/alternate-array.exit b/tests/qapi-schema/alternate-array.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/alternate-array.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/alternate-array.json b/tests/qapi-schema/alternate-array.json
new file mode 100644
index 0000000..25224c6
--- /dev/null
+++ b/tests/qapi-schema/alternate-array.json
@@ -0,0 +1,8 @@ 
+# FIXME: we should not allow array branches in anonymous unions
+# TODO: should we support this?
+{ 'type': 'One',
+  'data': { 'name': 'str' } }
+{ 'union': 'MyUnion',
+  'discriminator': {},
+  'data': { 'one': 'One',
+            'two': [ 'int' ] } }
diff --git a/tests/qapi-schema/alternate-array.out b/tests/qapi-schema/alternate-array.out
new file mode 100644
index 0000000..90dc22c
--- /dev/null
+++ b/tests/qapi-schema/alternate-array.out
@@ -0,0 +1,4 @@ 
+[OrderedDict([('type', 'One'), ('data', OrderedDict([('name', 'str')]))]),
+ OrderedDict([('union', 'MyUnion'), ('discriminator', OrderedDict()), ('data', OrderedDict([('one', 'One'), ('two', ['int'])]))])]
+[{'enum_name': 'MyUnionKind', 'enum_values': None}]
+[OrderedDict([('type', 'One'), ('data', OrderedDict([('name', 'str')]))])]
diff --git a/tests/qapi-schema/alternate-base.err b/tests/qapi-schema/alternate-base.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/alternate-base.exit b/tests/qapi-schema/alternate-base.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/alternate-base.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/alternate-base.json b/tests/qapi-schema/alternate-base.json
new file mode 100644
index 0000000..2d36db1
--- /dev/null
+++ b/tests/qapi-schema/alternate-base.json
@@ -0,0 +1,7 @@ 
+# FIXME: we should reject anonymous union with base type
+{ 'type': 'Base',
+  'data': { 'string': 'str' } }
+{ 'union': 'MyUnion',
+  'base': 'Base',
+  'discriminator': {},
+  'data': { 'number': 'int' } }
diff --git a/tests/qapi-schema/alternate-base.out b/tests/qapi-schema/alternate-base.out
new file mode 100644
index 0000000..7fb31f5
--- /dev/null
+++ b/tests/qapi-schema/alternate-base.out
@@ -0,0 +1,4 @@ 
+[OrderedDict([('type', 'Base'), ('data', OrderedDict([('string', 'str')]))]),
+ OrderedDict([('union', 'MyUnion'), ('base', 'Base'), ('discriminator', OrderedDict()), ('data', OrderedDict([('number', 'int')]))])]
+[{'enum_name': 'MyUnionKind', 'enum_values': None}]
+[OrderedDict([('type', 'Base'), ('data', OrderedDict([('string', 'str')]))])]
diff --git a/tests/qapi-schema/alternate-clash.err b/tests/qapi-schema/alternate-clash.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/alternate-clash.exit b/tests/qapi-schema/alternate-clash.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/alternate-clash.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/alternate-clash.json b/tests/qapi-schema/alternate-clash.json
new file mode 100644
index 0000000..7e2ef23
--- /dev/null
+++ b/tests/qapi-schema/alternate-clash.json
@@ -0,0 +1,4 @@ 
+# FIXME: we should detect C enum collisions in an anonymous union
+{ 'union': 'Union1',
+  'discriminator': {},
+  'data': { 'one': 'str', 'ONE': 'int' } }
diff --git a/tests/qapi-schema/alternate-clash.out b/tests/qapi-schema/alternate-clash.out
new file mode 100644
index 0000000..c6687fa
--- /dev/null
+++ b/tests/qapi-schema/alternate-clash.out
@@ -0,0 +1,3 @@ 
+[OrderedDict([('union', 'Union1'), ('discriminator', OrderedDict()), ('data', OrderedDict([('one', 'str'), ('ONE', 'int')]))])]
+[{'enum_name': 'Union1Kind', 'enum_values': None}]
+[]
diff --git a/tests/qapi-schema/alternate-conflict-dict.err b/tests/qapi-schema/alternate-conflict-dict.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/alternate-conflict-dict.exit b/tests/qapi-schema/alternate-conflict-dict.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/alternate-conflict-dict.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/alternate-conflict-dict.json b/tests/qapi-schema/alternate-conflict-dict.json
new file mode 100644
index 0000000..d2ed9de
--- /dev/null
+++ b/tests/qapi-schema/alternate-conflict-dict.json
@@ -0,0 +1,9 @@ 
+# FIXME: we should reject anonymous unions with multiple object branches
+{ 'type': 'One',
+  'data': { 'name': 'str' } }
+{ 'type': 'Two',
+  'data': { 'value': 'int' } }
+{ 'union': 'MyUnion',
+  'discriminator': {},
+  'data': { 'one': 'One',
+            'two': 'Two' } }
diff --git a/tests/qapi-schema/alternate-conflict-dict.out b/tests/qapi-schema/alternate-conflict-dict.out
new file mode 100644
index 0000000..b9ac945
--- /dev/null
+++ b/tests/qapi-schema/alternate-conflict-dict.out
@@ -0,0 +1,6 @@ 
+[OrderedDict([('type', 'One'), ('data', OrderedDict([('name', 'str')]))]),
+ OrderedDict([('type', 'Two'), ('data', OrderedDict([('value', 'int')]))]),
+ OrderedDict([('union', 'MyUnion'), ('discriminator', OrderedDict()), ('data', OrderedDict([('one', 'One'), ('two', 'Two')]))])]
+[{'enum_name': 'MyUnionKind', 'enum_values': None}]
+[OrderedDict([('type', 'One'), ('data', OrderedDict([('name', 'str')]))]),
+ OrderedDict([('type', 'Two'), ('data', OrderedDict([('value', 'int')]))])]
diff --git a/tests/qapi-schema/alternate-conflict-string.err b/tests/qapi-schema/alternate-conflict-string.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/alternate-conflict-string.exit b/tests/qapi-schema/alternate-conflict-string.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/alternate-conflict-string.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/alternate-conflict-string.json b/tests/qapi-schema/alternate-conflict-string.json
new file mode 100644
index 0000000..35245a3
--- /dev/null
+++ b/tests/qapi-schema/alternate-conflict-string.json
@@ -0,0 +1,7 @@ 
+# FIXME: we should reject anonymous unions with multiple string-like branches
+{ 'enum': 'Enum',
+  'data': [ 'hello', 'world' ] }
+{ 'union': 'MyUnion',
+  'discriminator': {},
+  'data': { 'one': 'str',
+            'two': 'Enum' } }
diff --git a/tests/qapi-schema/alternate-conflict-string.out b/tests/qapi-schema/alternate-conflict-string.out
new file mode 100644
index 0000000..e7b39a2
--- /dev/null
+++ b/tests/qapi-schema/alternate-conflict-string.out
@@ -0,0 +1,5 @@ 
+[OrderedDict([('enum', 'Enum'), ('data', ['hello', 'world'])]),
+ OrderedDict([('union', 'MyUnion'), ('discriminator', OrderedDict()), ('data', OrderedDict([('one', 'str'), ('two', 'Enum')]))])]
+[{'enum_name': 'Enum', 'enum_values': ['hello', 'world']},
+ {'enum_name': 'MyUnionKind', 'enum_values': None}]
+[]
diff --git a/tests/qapi-schema/alternate-good.err b/tests/qapi-schema/alternate-good.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/alternate-good.exit b/tests/qapi-schema/alternate-good.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/alternate-good.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/alternate-good.json b/tests/qapi-schema/alternate-good.json
new file mode 100644
index 0000000..73d0993
--- /dev/null
+++ b/tests/qapi-schema/alternate-good.json
@@ -0,0 +1,10 @@ 
+# Working example of anonymous union
+{ 'type': 'Data',
+  'data': { '*number': 'int', '*name': 'str' } }
+{ 'enum': 'Enum',
+  'data': [ 'hello', 'world' ] }
+{ 'union': 'MyUnion',
+  'discriminator': {},
+  'data': { 'value': 'int',
+            'string': 'Enum',
+            'struct': 'Data' } }
diff --git a/tests/qapi-schema/alternate-good.out b/tests/qapi-schema/alternate-good.out
new file mode 100644
index 0000000..b5117d1
--- /dev/null
+++ b/tests/qapi-schema/alternate-good.out
@@ -0,0 +1,6 @@ 
+[OrderedDict([('type', 'Data'), ('data', OrderedDict([('*number', 'int'), ('*name', 'str')]))]),
+ OrderedDict([('enum', 'Enum'), ('data', ['hello', 'world'])]),
+ OrderedDict([('union', 'MyUnion'), ('discriminator', OrderedDict()), ('data', OrderedDict([('value', 'int'), ('string', 'Enum'), ('struct', 'Data')]))])]
+[{'enum_name': 'Enum', 'enum_values': ['hello', 'world']},
+ {'enum_name': 'MyUnionKind', 'enum_values': None}]
+[OrderedDict([('type', 'Data'), ('data', OrderedDict([('*number', 'int'), ('*name', 'str')]))])]
diff --git a/tests/qapi-schema/alternate-nested.err b/tests/qapi-schema/alternate-nested.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/alternate-nested.exit b/tests/qapi-schema/alternate-nested.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/alternate-nested.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/alternate-nested.json b/tests/qapi-schema/alternate-nested.json
new file mode 100644
index 0000000..d5812bf
--- /dev/null
+++ b/tests/qapi-schema/alternate-nested.json
@@ -0,0 +1,7 @@ 
+# FIXME: we should reject a nested anonymous union branch
+{ 'union': 'Union1',
+  'discriminator': {},
+  'data': { 'name': 'str', 'value': 'int' } }
+{ 'union': 'Union2',
+  'discriminator': {},
+  'data': { 'nested': 'Union1' } }
diff --git a/tests/qapi-schema/alternate-nested.out b/tests/qapi-schema/alternate-nested.out
new file mode 100644
index 0000000..0137c1f
--- /dev/null
+++ b/tests/qapi-schema/alternate-nested.out
@@ -0,0 +1,5 @@ 
+[OrderedDict([('union', 'Union1'), ('discriminator', OrderedDict()), ('data', OrderedDict([('name', 'str'), ('value', 'int')]))]),
+ OrderedDict([('union', 'Union2'), ('discriminator', OrderedDict()), ('data', OrderedDict([('nested', 'Union1')]))])]
+[{'enum_name': 'Union1Kind', 'enum_values': None},
+ {'enum_name': 'Union2Kind', 'enum_values': None}]
+[]
diff --git a/tests/qapi-schema/alternate-unknown.err b/tests/qapi-schema/alternate-unknown.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/alternate-unknown.exit b/tests/qapi-schema/alternate-unknown.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/alternate-unknown.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/alternate-unknown.json b/tests/qapi-schema/alternate-unknown.json
new file mode 100644
index 0000000..0bab9c2
--- /dev/null
+++ b/tests/qapi-schema/alternate-unknown.json
@@ -0,0 +1,4 @@ 
+# FIXME: we should reject an anonymous union with unknown type in branch
+{ 'union': 'Union',
+  'discriminator': {},
+  'data': { 'unknown': 'MissingType' } }
diff --git a/tests/qapi-schema/alternate-unknown.out b/tests/qapi-schema/alternate-unknown.out
new file mode 100644
index 0000000..0911cdc
--- /dev/null
+++ b/tests/qapi-schema/alternate-unknown.out
@@ -0,0 +1,3 @@ 
+[OrderedDict([('union', 'Union'), ('discriminator', OrderedDict()), ('data', OrderedDict([('unknown', 'MissingType')]))])]
+[{'enum_name': 'UnionKind', 'enum_values': None}]
+[]
diff --git a/tests/qapi-schema/flat-union-bad-base.err b/tests/qapi-schema/flat-union-bad-base.err
new file mode 100644
index 0000000..5962ff4
--- /dev/null
+++ b/tests/qapi-schema/flat-union-bad-base.err
@@ -0,0 +1 @@ 
+tests/qapi-schema/flat-union-bad-base.json:9: Base 'OrderedDict([('enum1', 'TestEnum'), ('kind', 'str')])' is not a valid type
diff --git a/tests/qapi-schema/flat-union-bad-base.exit b/tests/qapi-schema/flat-union-bad-base.exit
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/tests/qapi-schema/flat-union-bad-base.exit
@@ -0,0 +1 @@ 
+1
diff --git a/tests/qapi-schema/flat-union-bad-base.json b/tests/qapi-schema/flat-union-bad-base.json
new file mode 100644
index 0000000..6c14132
--- /dev/null
+++ b/tests/qapi-schema/flat-union-bad-base.json
@@ -0,0 +1,13 @@ 
+# FIXME: poor message: we require the base to be an existing complex type
+# TODO: should we allow an anonymous inline base type?
+{ 'enum': 'TestEnum',
+  'data': [ 'value1', 'value2' ] }
+{ 'type': 'TestTypeA',
+  'data': { 'string': 'str' } }
+{ 'type': 'TestTypeB',
+  'data': { 'integer': 'int' } }
+{ 'union': 'TestUnion',
+  'base': { 'enum1': 'TestEnum', 'kind': 'str' },
+  'discriminator': 'enum1',
+  'data': { 'value1': 'TestTypeA',
+            'value2': 'TestTypeB' } }
diff --git a/tests/qapi-schema/flat-union-bad-base.out b/tests/qapi-schema/flat-union-bad-base.out
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/flat-union-bad-discriminator.err b/tests/qapi-schema/flat-union-bad-discriminator.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/flat-union-bad-discriminator.exit b/tests/qapi-schema/flat-union-bad-discriminator.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/flat-union-bad-discriminator.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/flat-union-bad-discriminator.json b/tests/qapi-schema/flat-union-bad-discriminator.json
new file mode 100644
index 0000000..1599a59
--- /dev/null
+++ b/tests/qapi-schema/flat-union-bad-discriminator.json
@@ -0,0 +1,14 @@ 
+# FIXME: we should require the discriminator to be a string naming a base-type member
+{ 'enum': 'TestEnum',
+  'data': [ 'value1', 'value2' ] }
+{ 'type': 'TestBase',
+  'data': { 'enum1': 'TestEnum', 'kind': 'str' } }
+{ 'type': 'TestTypeA',
+  'data': { 'string': 'str' } }
+{ 'type': 'TestTypeB',
+  'data': { 'integer': 'int' } }
+{ 'union': 'TestUnion',
+  'base': 'TestBase',
+  'discriminator': [],
+  'data': { 'kind1': 'TestTypeA',
+            'kind2': 'TestTypeB' } }
diff --git a/tests/qapi-schema/flat-union-bad-discriminator.out b/tests/qapi-schema/flat-union-bad-discriminator.out
new file mode 100644
index 0000000..b6ce217
--- /dev/null
+++ b/tests/qapi-schema/flat-union-bad-discriminator.out
@@ -0,0 +1,10 @@ 
+[OrderedDict([('enum', 'TestEnum'), ('data', ['value1', 'value2'])]),
+ OrderedDict([('type', 'TestBase'), ('data', OrderedDict([('enum1', 'TestEnum'), ('kind', 'str')]))]),
+ OrderedDict([('type', 'TestTypeA'), ('data', OrderedDict([('string', 'str')]))]),
+ OrderedDict([('type', 'TestTypeB'), ('data', OrderedDict([('integer', 'int')]))]),
+ OrderedDict([('union', 'TestUnion'), ('base', 'TestBase'), ('discriminator', []), ('data', OrderedDict([('kind1', 'TestTypeA'), ('kind2', 'TestTypeB')]))])]
+[{'enum_name': 'TestEnum', 'enum_values': ['value1', 'value2']},
+ {'enum_name': 'TestUnionKind', 'enum_values': None}]
+[OrderedDict([('type', 'TestBase'), ('data', OrderedDict([('enum1', 'TestEnum'), ('kind', 'str')]))]),
+ OrderedDict([('type', 'TestTypeA'), ('data', OrderedDict([('string', 'str')]))]),
+ OrderedDict([('type', 'TestTypeB'), ('data', OrderedDict([('integer', 'int')]))])]
diff --git a/tests/qapi-schema/flat-union-base-star.err b/tests/qapi-schema/flat-union-base-star.err
new file mode 100644
index 0000000..60e47ef
--- /dev/null
+++ b/tests/qapi-schema/flat-union-base-star.err
@@ -0,0 +1 @@ 
+tests/qapi-schema/flat-union-base-star.json:8: Base '**' is not a valid type
diff --git a/tests/qapi-schema/flat-union-base-star.exit b/tests/qapi-schema/flat-union-base-star.exit
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/tests/qapi-schema/flat-union-base-star.exit
@@ -0,0 +1 @@ 
+1
diff --git a/tests/qapi-schema/flat-union-base-star.json b/tests/qapi-schema/flat-union-base-star.json
new file mode 100644
index 0000000..994533a
--- /dev/null
+++ b/tests/qapi-schema/flat-union-base-star.json
@@ -0,0 +1,12 @@ 
+# we require the base to be an existing complex type
+{ 'enum': 'TestEnum',
+  'data': [ 'value1', 'value2' ] }
+{ 'type': 'TestTypeA',
+  'data': { 'string': 'str' } }
+{ 'type': 'TestTypeB',
+  'data': { 'integer': 'int' } }
+{ 'union': 'TestUnion',
+  'base': '**',
+  'discriminator': 'enum1',
+  'data': { 'value1': 'TestTypeA',
+            'value2': 'TestTypeB' } }
diff --git a/tests/qapi-schema/flat-union-base-star.out b/tests/qapi-schema/flat-union-base-star.out
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/flat-union-base-union.err b/tests/qapi-schema/flat-union-base-union.err
new file mode 100644
index 0000000..185bf51
--- /dev/null
+++ b/tests/qapi-schema/flat-union-base-union.err
@@ -0,0 +1 @@ 
+tests/qapi-schema/flat-union-base-union.json:11: Base 'UnionBase' is not a valid type
diff --git a/tests/qapi-schema/flat-union-base-union.exit b/tests/qapi-schema/flat-union-base-union.exit
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/tests/qapi-schema/flat-union-base-union.exit
@@ -0,0 +1 @@ 
+1
diff --git a/tests/qapi-schema/flat-union-base-union.json b/tests/qapi-schema/flat-union-base-union.json
new file mode 100644
index 0000000..838986c
--- /dev/null
+++ b/tests/qapi-schema/flat-union-base-union.json
@@ -0,0 +1,15 @@ 
+# FIXME: the error message needs help: we require the base to be a struct
+{ 'enum': 'TestEnum',
+  'data': [ 'value1', 'value2' ] }
+{ 'type': 'TestTypeA',
+  'data': { 'string': 'str' } }
+{ 'type': 'TestTypeB',
+  'data': { 'integer': 'int' } }
+{ 'union': 'UnionBase',
+  'data': { 'kind1': 'TestTypeA',
+            'kind2': 'TestTypeB' } }
+{ 'union': 'TestUnion',
+  'base': 'UnionBase',
+  'discriminator': 'type',
+  'data': { 'kind1': 'TestTypeA',
+            'kind2': 'TestTypeB' } }
diff --git a/tests/qapi-schema/flat-union-base-union.out b/tests/qapi-schema/flat-union-base-union.out
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/flat-union-branch-clash.err b/tests/qapi-schema/flat-union-branch-clash.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/flat-union-branch-clash.exit b/tests/qapi-schema/flat-union-branch-clash.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/flat-union-branch-clash.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/flat-union-branch-clash.json b/tests/qapi-schema/flat-union-branch-clash.json
new file mode 100644
index 0000000..4091477
--- /dev/null
+++ b/tests/qapi-schema/flat-union-branch-clash.json
@@ -0,0 +1,14 @@ 
+# FIXME: we should check for no duplicate keys between branches and base
+{ 'enum': 'TestEnum',
+  'data': [ 'value1', 'value2' ] }
+{ 'type': 'Base',
+  'data': { 'enum1': 'TestEnum', 'name': 'str' } }
+{ 'type': 'Branch1',
+  'data': { 'name': 'str' } }
+{ 'type': 'Branch2',
+  'data': { 'value': 'int' } }
+{ 'union': 'TestUnion',
+  'base': 'Base',
+  'discriminator': 'enum1',
+  'data': { 'value1': 'Branch1',
+            'value2': 'Branch2' } }
diff --git a/tests/qapi-schema/flat-union-branch-clash.out b/tests/qapi-schema/flat-union-branch-clash.out
new file mode 100644
index 0000000..5d54113
--- /dev/null
+++ b/tests/qapi-schema/flat-union-branch-clash.out
@@ -0,0 +1,9 @@ 
+[OrderedDict([('enum', 'TestEnum'), ('data', ['value1', 'value2'])]),
+ OrderedDict([('type', 'Base'), ('data', OrderedDict([('enum1', 'TestEnum'), ('name', 'str')]))]),
+ OrderedDict([('type', 'Branch1'), ('data', OrderedDict([('name', 'str')]))]),
+ OrderedDict([('type', 'Branch2'), ('data', OrderedDict([('value', 'int')]))]),
+ OrderedDict([('union', 'TestUnion'), ('base', 'Base'), ('discriminator', 'enum1'), ('data', OrderedDict([('value1', 'Branch1'), ('value2', 'Branch2')]))])]
+[{'enum_name': 'TestEnum', 'enum_values': ['value1', 'value2']}]
+[OrderedDict([('type', 'Base'), ('data', OrderedDict([('enum1', 'TestEnum'), ('name', 'str')]))]),
+ OrderedDict([('type', 'Branch1'), ('data', OrderedDict([('name', 'str')]))]),
+ OrderedDict([('type', 'Branch2'), ('data', OrderedDict([('value', 'int')]))])]
diff --git a/tests/qapi-schema/flat-union-inline.err b/tests/qapi-schema/flat-union-inline.err
new file mode 100644
index 0000000..51fbe54
--- /dev/null
+++ b/tests/qapi-schema/flat-union-inline.err
@@ -0,0 +1 @@ 
+tests/qapi-schema/flat-union-inline.json:7: Base 'OrderedDict([('enum1', 'TestEnum'), ('kind', 'str')])' is not a valid type
diff --git a/tests/qapi-schema/flat-union-inline.exit b/tests/qapi-schema/flat-union-inline.exit
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/tests/qapi-schema/flat-union-inline.exit
@@ -0,0 +1 @@ 
+1
diff --git a/tests/qapi-schema/flat-union-inline.json b/tests/qapi-schema/flat-union-inline.json
new file mode 100644
index 0000000..2bdffeb
--- /dev/null
+++ b/tests/qapi-schema/flat-union-inline.json
@@ -0,0 +1,11 @@ 
+# FIXME: poor message: we require branches to be a complex type name
+# TODO: should we allow anonymous inline types?
+{ 'enum': 'TestEnum',
+  'data': [ 'value1', 'value2' ] }
+{ 'type': 'Base',
+  'data': { 'enum1': 'TestEnum', 'kind': 'str' } }
+{ 'union': 'TestUnion',
+  'base': { 'enum1': 'TestEnum', 'kind': 'str' },
+  'discriminator': 'enum1',
+  'data': { 'value1': { 'string': 'str' },
+            'value2': { 'integer': 'int' } } }
diff --git a/tests/qapi-schema/flat-union-inline.out b/tests/qapi-schema/flat-union-inline.out
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/flat-union-int-branch.err b/tests/qapi-schema/flat-union-int-branch.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/flat-union-int-branch.exit b/tests/qapi-schema/flat-union-int-branch.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/flat-union-int-branch.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/flat-union-int-branch.json b/tests/qapi-schema/flat-union-int-branch.json
new file mode 100644
index 0000000..3543215
--- /dev/null
+++ b/tests/qapi-schema/flat-union-int-branch.json
@@ -0,0 +1,12 @@ 
+# FIXME: we should require flat union branches to be a complex type
+{ 'enum': 'TestEnum',
+  'data': [ 'value1', 'value2' ] }
+{ 'type': 'Base',
+  'data': { 'enum1': 'TestEnum' } }
+{ 'type': 'TestTypeB',
+  'data': { 'integer': 'int' } }
+{ 'union': 'TestUnion',
+  'base': 'Base',
+  'discriminator': 'enum1',
+  'data': { 'value1': 'int',
+            'value2': 'TestTypeB' } }
diff --git a/tests/qapi-schema/flat-union-int-branch.out b/tests/qapi-schema/flat-union-int-branch.out
new file mode 100644
index 0000000..cd40e6c
--- /dev/null
+++ b/tests/qapi-schema/flat-union-int-branch.out
@@ -0,0 +1,7 @@ 
+[OrderedDict([('enum', 'TestEnum'), ('data', ['value1', 'value2'])]),
+ OrderedDict([('type', 'Base'), ('data', OrderedDict([('enum1', 'TestEnum')]))]),
+ OrderedDict([('type', 'TestTypeB'), ('data', OrderedDict([('integer', 'int')]))]),
+ OrderedDict([('union', 'TestUnion'), ('base', 'Base'), ('discriminator', 'enum1'), ('data', OrderedDict([('value1', 'int'), ('value2', 'TestTypeB')]))])]
+[{'enum_name': 'TestEnum', 'enum_values': ['value1', 'value2']}]
+[OrderedDict([('type', 'Base'), ('data', OrderedDict([('enum1', 'TestEnum')]))]),
+ OrderedDict([('type', 'TestTypeB'), ('data', OrderedDict([('integer', 'int')]))])]
diff --git a/tests/qapi-schema/flat-union-no-base.err b/tests/qapi-schema/flat-union-no-base.err
index a59749e..97323a0 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:7: Flat union 'TestUnion' must have a base field
+tests/qapi-schema/flat-union-no-base.json:9: Flat union 'TestUnion' must have a base field
diff --git a/tests/qapi-schema/flat-union-no-base.json b/tests/qapi-schema/flat-union-no-base.json
index 50f2673..08a0247 100644
--- a/tests/qapi-schema/flat-union-no-base.json
+++ b/tests/qapi-schema/flat-union-no-base.json
@@ -1,10 +1,12 @@ 
+# FIXME: flat unions should require a base
+# TODO: simple unions should be able to use an enum discriminator
 { 'type': 'TestTypeA',
   'data': { 'string': 'str' } }
-
 { 'type': 'TestTypeB',
   'data': { 'integer': 'int' } }
-
+{ 'enum': 'Enum',
+  'data': [ 'value1', 'value2' ] }
 { 'union': 'TestUnion',
-  'discriminator': 'enum1',
+  'discriminator': 'Enum',
   'data': { 'value1': 'TestTypeA',
             'value2': 'TestTypeB' } }
diff --git a/tests/qapi-schema/flat-union-optional-discriminator.err b/tests/qapi-schema/flat-union-optional-discriminator.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/flat-union-optional-discriminator.exit b/tests/qapi-schema/flat-union-optional-discriminator.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/flat-union-optional-discriminator.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/flat-union-optional-discriminator.json b/tests/qapi-schema/flat-union-optional-discriminator.json
new file mode 100644
index 0000000..ece0d31
--- /dev/null
+++ b/tests/qapi-schema/flat-union-optional-discriminator.json
@@ -0,0 +1,10 @@ 
+# FIXME: we should require the discriminator to be non-optional
+{ 'enum': 'Enum', 'data': [ 'one', 'two' ] }
+{ 'type': 'Base',
+  'data': { '*switch': 'Enum' } }
+{ 'type': 'Branch', 'data': { 'name': 'str' } }
+{ 'union': 'MyUnion',
+  'base': 'Base',
+  'discriminator': '*switch',
+  'data': { 'one': 'Branch',
+            'two': 'Branch' } }
diff --git a/tests/qapi-schema/flat-union-optional-discriminator.out b/tests/qapi-schema/flat-union-optional-discriminator.out
new file mode 100644
index 0000000..bb7db00
--- /dev/null
+++ b/tests/qapi-schema/flat-union-optional-discriminator.out
@@ -0,0 +1,7 @@ 
+[OrderedDict([('enum', 'Enum'), ('data', ['one', 'two'])]),
+ OrderedDict([('type', 'Base'), ('data', OrderedDict([('*switch', 'Enum')]))]),
+ OrderedDict([('type', 'Branch'), ('data', OrderedDict([('name', 'str')]))]),
+ OrderedDict([('union', 'MyUnion'), ('base', 'Base'), ('discriminator', '*switch'), ('data', OrderedDict([('one', 'Branch'), ('two', 'Branch')]))])]
+[{'enum_name': 'Enum', 'enum_values': ['one', 'two']}]
+[OrderedDict([('type', 'Base'), ('data', OrderedDict([('*switch', 'Enum')]))]),
+ OrderedDict([('type', 'Branch'), ('data', OrderedDict([('name', 'str')]))])]
diff --git a/tests/qapi-schema/union-bad-branch.err b/tests/qapi-schema/union-bad-branch.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/union-bad-branch.exit b/tests/qapi-schema/union-bad-branch.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/union-bad-branch.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/union-bad-branch.json b/tests/qapi-schema/union-bad-branch.json
new file mode 100644
index 0000000..11e46de
--- /dev/null
+++ b/tests/qapi-schema/union-bad-branch.json
@@ -0,0 +1,8 @@ 
+# FIXME: we should reject normal unions where branches would collide in C
+{ 'type': 'One',
+  'data': { 'string': 'str' } }
+{ 'type': 'Two',
+  'data': { 'number': 'int' } }
+{ 'union': 'MyUnion',
+  'data': { 'one': 'One',
+            'ONE': 'Two' } }
diff --git a/tests/qapi-schema/union-bad-branch.out b/tests/qapi-schema/union-bad-branch.out
new file mode 100644
index 0000000..6baf01b
--- /dev/null
+++ b/tests/qapi-schema/union-bad-branch.out
@@ -0,0 +1,6 @@ 
+[OrderedDict([('type', 'One'), ('data', OrderedDict([('string', 'str')]))]),
+ OrderedDict([('type', 'Two'), ('data', OrderedDict([('number', 'int')]))]),
+ OrderedDict([('union', 'MyUnion'), ('data', OrderedDict([('one', 'One'), ('ONE', 'Two')]))])]
+[{'enum_name': 'MyUnionKind', 'enum_values': None}]
+[OrderedDict([('type', 'One'), ('data', OrderedDict([('string', 'str')]))]),
+ OrderedDict([('type', 'Two'), ('data', OrderedDict([('number', 'int')]))])]
diff --git a/tests/qapi-schema/union-base-no-discriminator.err b/tests/qapi-schema/union-base-no-discriminator.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/union-base-no-discriminator.exit b/tests/qapi-schema/union-base-no-discriminator.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/union-base-no-discriminator.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/union-base-no-discriminator.json b/tests/qapi-schema/union-base-no-discriminator.json
new file mode 100644
index 0000000..c8cba3a
--- /dev/null
+++ b/tests/qapi-schema/union-base-no-discriminator.json
@@ -0,0 +1,14 @@ 
+# FIXME: we should reject simple unions with a base
+{ 'type': 'TestTypeA',
+  'data': { 'string': 'str' } }
+
+{ 'type': 'TestTypeB',
+  'data': { 'integer': 'int' } }
+
+{ 'type': 'Base',
+  'data': { 'string': 'str' } }
+
+{ 'union': 'TestUnion',
+  'base': 'Base',
+  'data': { 'value1': 'TestTypeA',
+            'value2': 'TestTypeB' } }
diff --git a/tests/qapi-schema/union-base-no-discriminator.out b/tests/qapi-schema/union-base-no-discriminator.out
new file mode 100644
index 0000000..505fd57
--- /dev/null
+++ b/tests/qapi-schema/union-base-no-discriminator.out
@@ -0,0 +1,8 @@ 
+[OrderedDict([('type', 'TestTypeA'), ('data', OrderedDict([('string', 'str')]))]),
+ OrderedDict([('type', 'TestTypeB'), ('data', OrderedDict([('integer', 'int')]))]),
+ OrderedDict([('type', 'Base'), ('data', OrderedDict([('string', 'str')]))]),
+ OrderedDict([('union', 'TestUnion'), ('base', 'Base'), ('data', OrderedDict([('value1', 'TestTypeA'), ('value2', 'TestTypeB')]))])]
+[{'enum_name': 'TestUnionKind', 'enum_values': None}]
+[OrderedDict([('type', 'TestTypeA'), ('data', OrderedDict([('string', 'str')]))]),
+ OrderedDict([('type', 'TestTypeB'), ('data', OrderedDict([('integer', 'int')]))]),
+ OrderedDict([('type', 'Base'), ('data', OrderedDict([('string', 'str')]))])]
diff --git a/tests/qapi-schema/union-invalid-base.err b/tests/qapi-schema/union-invalid-base.err
index 938f969..3cc82c0 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:7: Base 'TestBaseWrong' is not a valid type
+tests/qapi-schema/union-invalid-base.json:8: Base 'int' is not a valid type
diff --git a/tests/qapi-schema/union-invalid-base.json b/tests/qapi-schema/union-invalid-base.json
index 1fa4930..bc5dc8d 100644
--- a/tests/qapi-schema/union-invalid-base.json
+++ b/tests/qapi-schema/union-invalid-base.json
@@ -1,3 +1,4 @@ 
+# a union base type must be a struct
 { 'type': 'TestTypeA',
   'data': { 'string': 'str' } }

@@ -5,6 +6,7 @@ 
   'data': { 'integer': 'int' } }

 { 'union': 'TestUnion',
-  'base': 'TestBaseWrong',
+  'base': 'int',
+  'discriminator': 'int',
   'data': { 'value1': 'TestTypeA',
             'value2': 'TestTypeB' } }
diff --git a/tests/qapi-schema/union-max.err b/tests/qapi-schema/union-max.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/union-max.exit b/tests/qapi-schema/union-max.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/union-max.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/union-max.json b/tests/qapi-schema/union-max.json
new file mode 100644
index 0000000..45648c4
--- /dev/null
+++ b/tests/qapi-schema/union-max.json
@@ -0,0 +1,3 @@ 
+# FIXME: we should reject 'max' branch in a union, for collision with C enum
+{ 'union': 'Union',
+  'data': { 'max': 'int' } }
diff --git a/tests/qapi-schema/union-max.out b/tests/qapi-schema/union-max.out
new file mode 100644
index 0000000..2757d36
--- /dev/null
+++ b/tests/qapi-schema/union-max.out
@@ -0,0 +1,3 @@ 
+[OrderedDict([('union', 'Union'), ('data', OrderedDict([('max', 'int')]))])]
+[{'enum_name': 'UnionKind', 'enum_values': None}]
+[]
diff --git a/tests/qapi-schema/union-optional-branch.err b/tests/qapi-schema/union-optional-branch.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/union-optional-branch.exit b/tests/qapi-schema/union-optional-branch.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/union-optional-branch.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/union-optional-branch.json b/tests/qapi-schema/union-optional-branch.json
new file mode 100644
index 0000000..c513db7
--- /dev/null
+++ b/tests/qapi-schema/union-optional-branch.json
@@ -0,0 +1,2 @@ 
+# FIXME: union branches cannot be optional
+{ 'union': 'Union', 'data': { '*a': 'int', 'b': 'str' } }
diff --git a/tests/qapi-schema/union-optional-branch.out b/tests/qapi-schema/union-optional-branch.out
new file mode 100644
index 0000000..b03b5d2
--- /dev/null
+++ b/tests/qapi-schema/union-optional-branch.out
@@ -0,0 +1,3 @@ 
+[OrderedDict([('union', 'Union'), ('data', OrderedDict([('*a', 'int'), ('b', 'str')]))])]
+[{'enum_name': 'UnionKind', 'enum_values': None}]
+[]
diff --git a/tests/qapi-schema/union-unknown.err b/tests/qapi-schema/union-unknown.err
new file mode 100644
index 0000000..e69de29
diff --git a/tests/qapi-schema/union-unknown.exit b/tests/qapi-schema/union-unknown.exit
new file mode 100644
index 0000000..573541a
--- /dev/null
+++ b/tests/qapi-schema/union-unknown.exit
@@ -0,0 +1 @@ 
+0
diff --git a/tests/qapi-schema/union-unknown.json b/tests/qapi-schema/union-unknown.json
new file mode 100644
index 0000000..258f1d3
--- /dev/null
+++ b/tests/qapi-schema/union-unknown.json
@@ -0,0 +1,3 @@ 
+# FIXME: we should reject a union with unknown type in branch
+{ 'union': 'Union',
+  'data': { 'unknown': 'MissingType' } }
diff --git a/tests/qapi-schema/union-unknown.out b/tests/qapi-schema/union-unknown.out
new file mode 100644
index 0000000..8223dcf
--- /dev/null
+++ b/tests/qapi-schema/union-unknown.out
@@ -0,0 +1,3 @@ 
+[OrderedDict([('union', 'Union'), ('data', OrderedDict([('unknown', 'MissingType')]))])]
+[{'enum_name': 'UnionKind', 'enum_values': None}]
+[]