tests/qapi-schema/struct-base-clash-deep.json

# Reject attempts to duplicate QMP members
# Here, 'name' would have to appear twice on the wire, locally and
# indirectly for the grandparent base; the collision doesn't care that
# one instance is optional.
{ 'struct': 'Base',
  'data': { 'name': 'str' } }
{ 'struct': 'Mid',
  'base': 'Base',
  'data': { 'value': 'int' } }
{ 'struct': 'Sub',
  'base': 'Mid',
  'data': { '*name': 'str' } }
qapi: Test for various name collisions Expose some weaknesses in the generator: we don't always forbid the generation of structs that contain multiple members that map to the same C or QMP name. This has already been marked FIXME in qapi.py in commit d90675f, but having more tests will make sure future patches produce desired behavior; and updating existing patches to better document things doesn't hurt, either. Some of these collisions are already caught in the old-style parser checks, but ultimately we want all collisions to be caught in the new-style QAPISchema*.check() methods. This patch focuses on C struct members, and does not consider collisions between commands and events (affecting C function names), or even collisions between generated C type names with user type names (for things like automatic FOOList struct representing array types or FOOKind for an implicit enum). There are two types of struct collisions we want to catch: 1) Collision between two keys in a JSON object. qapi.py prevents that within a single struct (see test duplicate-key), but it is possible to have collisions between a type's members and its base type's members (existing tests struct-base-clash, struct-base-clash-deep), and its flat union variant members (renamed test flat-union-clash-member). 2) Collision between two members of the C struct that is generated for a given QAPI type: a) Multiple QAPI names map to the same C name (new test args-name-clash) b) A QAPI name maps to a C name that is used for another purpose (new tests flat-union-clash-branch, struct-base-clash-base, union-clash-data). We already fixed some such cases in commit 0f61af3e and 1e6c1616, but more remain. c) Two C names generated for other purposes clash (updated test alternate-clash, new test union-clash-branches, union-clash-type, flat-union-clash-type) Ultimately, if we need to have a flat union where a tag value clashes with a base member name, we could change the generator to name the union (using 'foo.u.value' rather than 'foo.value') or otherwise munge the C name corresponding to tag values. But unless such a need arises, it will probably be easier to just forbid these collisions. Some of these negative tests will be deleted later, and positive tests added to qapi-schema-test.json in their place, when the generator code is reworked to avoid particular code generation collisions in class 2). [Note that viewing this patch with git rename detection enabled may see some confusion due to renaming some tests while adding others, but where the content is similar enough that git picks the wrong pre- and post-patch files to associate] Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1443565276-4535-6-git-send-email-eblake@redhat.com> [Improve commit message and comments a bit, drop an unrelated test] Signed-off-by: Markus Armbruster <armbru@redhat.com> 2015-09-29 16:21:03 -06:00			`# Reject attempts to duplicate QMP members`
			`# Here, 'name' would have to appear twice on the wire, locally and`
			`# indirectly for the grandparent base; the collision doesn't care that`
			`# one instance is optional.`
qapi: Check for member name conflicts with a base class Our type inheritance for both 'struct' and for flat 'union' merges key/value pairs from the base class with those from the type in question. Although the C code currently boxes things so that there is a distinction between which member is referred to, the QMP wire format does not allow passing a key more than once in a single object. Besides, if we ever change the generated C code to not be quite so boxy, we'd want to avoid duplicate member names there, too. Fix a testsuite entry added in an earlier patch, as well as adding a couple more tests to ensure we have appropriate coverage. Ensure that collisions are detected, regardless of whether there is a difference in opinion on whether the member name is optional. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> 2015-05-04 09:05:37 -06:00			`{ 'struct': 'Base',`
			`'data': { 'name': 'str' } }`
			`{ 'struct': 'Mid',`
			`'base': 'Base',`
			`'data': { 'value': 'int' } }`
			`{ 'struct': 'Sub',`
			`'base': 'Mid',`
			`'data': { '*name': 'str' } }`