[Qemu-devel] [PATCH v7 03/15] qapi: Require all branches of flat union enum to be covered

[Eric Blake <eblake@redhat.com>]

We were previously enforcing that all flat union branches were
found in the corresponding enum, but not that all enum values
were covered by branches.  The resulting generated code would
abort() if the user passes the uncovered enum value.

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

---
v7: new patch
---
 scripts/qapi.py                                     | 8 ++++++++
 tests/Makefile                                      | 1 +
 tests/qapi-schema/flat-union-incomplete-branch.err  | 1 +
 tests/qapi-schema/flat-union-incomplete-branch.exit | 1 +
 tests/qapi-schema/flat-union-incomplete-branch.json | 9 +++++++++
 tests/qapi-schema/flat-union-incomplete-branch.out  | 0
 6 files changed, 20 insertions(+)
 create mode 100644 tests/qapi-schema/flat-union-incomplete-branch.err
 create mode 100644 tests/qapi-schema/flat-union-incomplete-branch.exit
 create mode 100644 tests/qapi-schema/flat-union-incomplete-branch.json
 create mode 100644 tests/qapi-schema/flat-union-incomplete-branch.out

diff --git a/scripts/qapi.py b/scripts/qapi.py
index 4dde43a..82d96e2 100644
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -612,6 +612,14 @@ def check_union(expr, expr_info):
                                     "enum '%s'" %
                                     (key, enum_define["enum_name"]))

+    # If discriminator is user-defined, ensure all values are covered
+    if enum_define:
+        for value in enum_define['enum_values']:
+            if value not in members.keys():
+                raise QAPIExprError(expr_info,
+                                    "Union '%s' data missing '%s' branch"
+                                    % (name, value))
+

 def check_alternate(expr, expr_info):
     name = expr['alternate']
diff --git a/tests/Makefile b/tests/Makefile
index 0d06406..c608f9a 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -314,6 +314,7 @@ qapi-schema += flat-union-base-any.json
 qapi-schema += flat-union-base-union.json
 qapi-schema += flat-union-clash-member.json
 qapi-schema += flat-union-empty.json
+qapi-schema += flat-union-incomplete-branch.json
 qapi-schema += flat-union-inline.json
 qapi-schema += flat-union-int-branch.json
 qapi-schema += flat-union-invalid-branch-key.json
diff --git a/tests/qapi-schema/flat-union-incomplete-branch.err b/tests/qapi-schema/flat-union-incomplete-branch.err
new file mode 100644
index 0000000..e826bf0
--- /dev/null
+++ b/tests/qapi-schema/flat-union-incomplete-branch.err
@@ -0,0 +1 @@
+tests/qapi-schema/flat-union-incomplete-branch.json:6: Union 'TestUnion' data missing 'value2' branch
diff --git a/tests/qapi-schema/flat-union-incomplete-branch.exit b/tests/qapi-schema/flat-union-incomplete-branch.exit
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/tests/qapi-schema/flat-union-incomplete-branch.exit
@@ -0,0 +1 @@
+1
diff --git a/tests/qapi-schema/flat-union-incomplete-branch.json b/tests/qapi-schema/flat-union-incomplete-branch.json
new file mode 100644
index 0000000..25a411b
--- /dev/null
+++ b/tests/qapi-schema/flat-union-incomplete-branch.json
@@ -0,0 +1,9 @@
+# we require all branches of the union to be covered
+{ 'enum': 'TestEnum',
+  'data': [ 'value1', 'value2' ] }
+{ 'struct': 'TestTypeA',
+  'data': { 'string': 'str' } }
+{ 'union': 'TestUnion',
+  'base': { 'type': 'TestEnum' },
+  'discriminator': 'type',
+  'data': { 'value1': 'TestTypeA' } }
diff --git a/tests/qapi-schema/flat-union-incomplete-branch.out b/tests/qapi-schema/flat-union-incomplete-branch.out
new file mode 100644
index 0000000..e69de29
-- 
2.5.5