[PATCH v2 0/5] qapi: Add feature flags to enum members

[Markus Armbruster <armbru@redhat.com>]

PATCH 1+2 add feature flags to enum members.  Awkward due to an
introspection design mistake; see PATCH 1 for details.

PATCH 3+4 implement policy deprecated-input={reject,crash} for enum
values.

Policy deprecated-output=hide is not implemented, because we can't
hide a value without hiding the entire member, which is almost
certainly more than the requester of this policy bargained for.
Perhaps we want a new policy deprecated-output=hide-or-else-crash to
help us catch unwanted use of deprecated enum values.  Perhaps we want
deprecated-output=hide to behave that way together with
deprecated-input=crash.  Or even always.  Thoughts?

PATCH 5 puts the new feature flags to use.  It's RFC because it makes
sense only on top of Vladimir's deprecation of drive-backup.  See its
commit message for a reference.

I prefer to commit new features together with a use outside tests/.
PATCH 5 adds such a use, but it's RFC, because it depends on
Vladimir's work.  Perhaps another use pops up.  I can delay this work
in the hope of a use becoming ready, but the feature flags work I have
in the pipeline will eventually force my hand.

v2:
* Rebased with straightforward conflicts.
* PATCH 1-4: No longer RFC.
* PATCH 1: "Since" information fixed [Eric].  Commit message updated
  to reflect feedback.
* PATCH 2: Commit message amended to point out special feature flag
 'deprecated' is ignored at this stage.
* PATCH 4: Documentation updated.  Commit message tweaked.

Markus Armbruster (5):
  qapi: Enable enum member introspection to show more than name
  qapi: Add feature flags to enum members
  qapi: Move compat policy from QObject to generic visitor
  qapi: Implement deprecated-input={reject,crash} for enum values
  block: Deprecate transaction type drive-backup

 docs/devel/qapi-code-gen.rst                  | 10 ++++---
 qapi/compat.json                              |  3 +++
 qapi/introspect.json                          | 24 +++++++++++++++--
 qapi/transaction.json                         |  5 +++-
 include/qapi/qobject-input-visitor.h          |  4 ---
 include/qapi/qobject-output-visitor.h         |  4 ---
 include/qapi/util.h                           |  6 ++++-
 include/qapi/visitor-impl.h                   |  3 +++
 include/qapi/visitor.h                        |  9 +++++++
 qapi/qapi-visit-core.c                        | 27 ++++++++++++++++---
 qapi/qmp-dispatch.c                           |  4 +--
 qapi/qobject-input-visitor.c                  | 14 +---------
 qapi/qobject-output-visitor.c                 | 14 +---------
 scripts/qapi/expr.py                          |  3 ++-
 scripts/qapi/introspect.py                    | 19 ++++++++++---
 scripts/qapi/schema.py                        | 22 +++++++++++++--
 scripts/qapi/types.py                         | 17 +++++++++++-
 tests/qapi-schema/doc-good.json               |  5 +++-
 tests/qapi-schema/doc-good.out                |  3 +++
 tests/qapi-schema/doc-good.txt                |  3 +++
 .../qapi-schema/enum-dict-member-unknown.err  |  2 +-
 tests/qapi-schema/qapi-schema-test.json       |  3 ++-
 tests/qapi-schema/qapi-schema-test.out        |  1 +
 tests/qapi-schema/test-qapi.py                |  1 +
 24 files changed, 149 insertions(+), 57 deletions(-)

-- 
2.31.1