qapi: Drop simple unions

Simple unions predate flat unions.  Having both complicates the QAPI
schema language and the QAPI generator.  We haven't been using simple
unions in new code for a long time, because they are less flexible and
somewhat awkward on the wire.

The previous commits eliminated simple union from the tree.  Now drop
them from the QAPI schema language entirely, and update mentions of
"flat union" to just "union".

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210917143134.412106-22-armbru@redhat.com>

10 files changed, 10 insertions, 10 deletions

diff --git a/tests/qapi-schema/flat-union-array-branch.json b/tests/qapi-schema/flat-union-array-branch.json
index 0b98820a8f..6dda7ec379 100644
--- a/tests/qapi-schema/flat-union-array-branch.json
+++ b/tests/qapi-schema/flat-union-array-branch.json
@@ -1,4 +1,4 @@
-# we require flat union branches to be a struct
+# we require union branches to be a struct
 { 'enum': 'TestEnum',
   'data': [ 'value1', 'value2' ] }
 { 'struct': 'Base',
diff --git a/tests/qapi-schema/flat-union-empty.json b/tests/qapi-schema/flat-union-empty.json
index 83e1cc7b96..584ed6098c 100644
--- a/tests/qapi-schema/flat-union-empty.json
+++ b/tests/qapi-schema/flat-union-empty.json
@@ -1,4 +1,4 @@
-# flat union discriminator cannot be empty
+# union discriminator enum cannot be empty
 { 'enum': 'Empty', 'data': [ ] }
 { 'struct': 'Base', 'data': { 'type': 'Empty' } }
 { 'union': 'Union', 'base': 'Base', 'discriminator': 'type', 'data': { } }
diff --git a/tests/qapi-schema/flat-union-int-branch.json b/tests/qapi-schema/flat-union-int-branch.json
index 9370c349e8..567043d9d2 100644
--- a/tests/qapi-schema/flat-union-int-branch.json
+++ b/tests/qapi-schema/flat-union-int-branch.json
@@ -1,4 +1,4 @@
-# we require flat union branches to be a struct
+# we require union branches to be a struct
 { 'enum': 'TestEnum',
   'data': [ 'value1', 'value2' ] }
 { 'struct': 'Base',
diff --git a/tests/qapi-schema/flat-union-no-base.err b/tests/qapi-schema/flat-union-no-base.err
index 5167565b00..c60482f96b 100644
--- a/tests/qapi-schema/flat-union-no-base.err
+++ b/tests/qapi-schema/flat-union-no-base.err
@@ -1,2 +1,2 @@
 flat-union-no-base.json: In union 'TestUnion':
-flat-union-no-base.json:8: 'discriminator' requires 'base'
+flat-union-no-base.json:8: union misses key 'base'
diff --git a/tests/qapi-schema/flat-union-no-base.json b/tests/qapi-schema/flat-union-no-base.json
index 327877b563..f6fe12da3b 100644
--- a/tests/qapi-schema/flat-union-no-base.json
+++ b/tests/qapi-schema/flat-union-no-base.json
@@ -1,4 +1,4 @@
-# flat unions require a base
+# unions require a base
 { 'struct': 'TestTypeA',
   'data': { 'string': 'str' } }
 { 'struct': 'TestTypeB',
diff --git a/tests/qapi-schema/qapi-schema-test.json b/tests/qapi-schema/qapi-schema-test.json
index 20f4cc0cfa..2ec50109cb 100644
--- a/tests/qapi-schema/qapi-schema-test.json
+++ b/tests/qapi-schema/qapi-schema-test.json
@@ -30,7 +30,7 @@
 { 'struct': 'Empty1', 'data': { } }
 { 'struct': 'Empty2', 'base': 'Empty1', 'data': { } }
 
-# Likewise for an empty flat union
+# Likewise for an empty union
 { 'union': 'Union',
   'base': { 'type': 'EnumOne' }, 'discriminator': 'type',
   'data': { } }
diff --git a/tests/qapi-schema/reserved-member-u.json b/tests/qapi-schema/reserved-member-u.json
index 2bfb8f59b6..d982ab5e0c 100644
--- a/tests/qapi-schema/reserved-member-u.json
+++ b/tests/qapi-schema/reserved-member-u.json
@@ -2,6 +2,6 @@
 # We reject use of 'u' as a member name, to allow it for internal use in
 # putting union branch members in a separate namespace from QMP members.
 # This is true even for non-unions, because it is possible to convert a
-# struct to flat union while remaining backwards compatible in QMP.
+# struct to union while remaining backwards compatible in QMP.
 # TODO - we could munge the member name to 'q_u' to avoid the collision
 { 'struct': 'Oops', 'data': { '*u': 'str' } }
diff --git a/tests/qapi-schema/union-base-empty.json b/tests/qapi-schema/union-base-empty.json
index d1843d33b4..6f8ef000db 100644
--- a/tests/qapi-schema/union-base-empty.json
+++ b/tests/qapi-schema/union-base-empty.json
@@ -1,4 +1,4 @@
-# Flat union with empty base and therefore without discriminator
+# Union with empty base and therefore without discriminator
 
 { 'struct': 'Empty', 'data': { } }
 
diff --git a/tests/qapi-schema/union-base-no-discriminator.err b/tests/qapi-schema/union-base-no-discriminator.err
index 9cd5d11b0b..a730b7fd3c 100644
--- a/tests/qapi-schema/union-base-no-discriminator.err
+++ b/tests/qapi-schema/union-base-no-discriminator.err
@@ -1,2 +1,2 @@
 union-base-no-discriminator.json: In union 'TestUnion':
-union-base-no-discriminator.json:11: 'base' requires 'discriminator'
+union-base-no-discriminator.json:11: union misses key 'discriminator'
diff --git a/tests/qapi-schema/union-base-no-discriminator.json b/tests/qapi-schema/union-base-no-discriminator.json
index 1409cf5c9e..2e7cae9b22 100644
--- a/tests/qapi-schema/union-base-no-discriminator.json
+++ b/tests/qapi-schema/union-base-no-discriminator.json
@@ -1,4 +1,4 @@
-# we reject simple unions with a base (or flat unions without discriminator)
+# we reject unions without discriminator
 { 'struct': 'TestTypeA',
   'data': { 'string': 'str' } }