tests/qapi-schema/union-bad-branch.json

# we 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' } }