This series introduces alias definitions for QAPI object types (structs
and unions).

This allows using the same QAPI type and visitor even when the syntax
has some variations between different external interfaces such as QMP
and the command line.

It also provides a new tool for evolving the schema while maintaining
backwards compatibility (possibly during a deprecation period).

The first user is intended to be a QAPIfied -chardev command line
option, for which I'll send a separate series. A git tag is available
that contains both this series and the chardev changes that make use of
it:

    https://repo.or.cz/qemu/kevin.git qapi-alias-chardev-v2

v2:
- Renamed 'alias' to 'name' in all data structures describing aliases
- Tons of new or changed comments and other documentation
- Be more explicit that empty 'source' is invalid and assert it
- Fixed full_name_so() for lists (added a parameter to tell the function
  whether the name of a list member or the list itself is meant)
- Changed some QAPI generator error messages
- Assert the type of parameters in QAPISchemaAlias.__init__()

Kevin Wolf (6):
  qapi: Add interfaces for alias support to Visitor
  qapi: Remember alias definitions in qobject-input-visitor
  qapi: Simplify full_name_nth() in qobject-input-visitor
  qapi: Apply aliases in qobject-input-visitor
  qapi: Add support for aliases
  tests/qapi-schema: Test cases for aliases

 docs/devel/qapi-code-gen.txt                  | 105 ++++-
 docs/sphinx/qapidoc.py                        |   2 +-
 include/qapi/visitor-impl.h                   |  12 +
 include/qapi/visitor.h                        |  44 ++
 qapi/qapi-visit-core.c                        |  22 +
 qapi/qobject-input-visitor.c                  | 402 ++++++++++++++++--
 scripts/qapi/expr.py                          |  36 +-
 scripts/qapi/schema.py                        |  30 +-
 scripts/qapi/types.py                         |   4 +-
 scripts/qapi/visit.py                         |  34 +-
 tests/qapi-schema/test-qapi.py                |   7 +-
 tests/qapi-schema/alias-bad-type.err          |   2 +
 tests/qapi-schema/alias-bad-type.json         |   3 +
 tests/qapi-schema/alias-bad-type.out          |   0
 tests/qapi-schema/alias-missing-source.err    |   2 +
 tests/qapi-schema/alias-missing-source.json   |   3 +
 tests/qapi-schema/alias-missing-source.out    |   0
 tests/qapi-schema/alias-name-bad-type.err     |   2 +
 tests/qapi-schema/alias-name-bad-type.json    |   3 +
 tests/qapi-schema/alias-name-bad-type.out     |   0
 tests/qapi-schema/alias-source-bad-type.err   |   2 +
 tests/qapi-schema/alias-source-bad-type.json  |   3 +
 tests/qapi-schema/alias-source-bad-type.out   |   0
 .../alias-source-elem-bad-type.err            |   2 +
 .../alias-source-elem-bad-type.json           |   3 +
 .../alias-source-elem-bad-type.out            |   0
 tests/qapi-schema/alias-source-empty.err      |   2 +
 tests/qapi-schema/alias-source-empty.json     |   3 +
 tests/qapi-schema/alias-source-empty.out      |   0
 tests/qapi-schema/alias-unknown-key.err       |   3 +
 tests/qapi-schema/alias-unknown-key.json      |   3 +
 tests/qapi-schema/alias-unknown-key.out       |   0
 tests/qapi-schema/aliases-bad-type.err        |   2 +
 tests/qapi-schema/aliases-bad-type.json       |   3 +
 tests/qapi-schema/aliases-bad-type.out        |   0
 tests/qapi-schema/double-type.err             |   2 +-
 tests/qapi-schema/meson.build                 |   8 +
 tests/qapi-schema/qapi-schema-test.json       |  24 ++
 tests/qapi-schema/qapi-schema-test.out        |  29 ++
 tests/qapi-schema/unknown-expr-key.err        |   2 +-
 40 files changed, 757 insertions(+), 47 deletions(-)
 create mode 100644 tests/qapi-schema/alias-bad-type.err
 create mode 100644 tests/qapi-schema/alias-bad-type.json
 create mode 100644 tests/qapi-schema/alias-bad-type.out
 create mode 100644 tests/qapi-schema/alias-missing-source.err
 create mode 100644 tests/qapi-schema/alias-missing-source.json
 create mode 100644 tests/qapi-schema/alias-missing-source.out
 create mode 100644 tests/qapi-schema/alias-name-bad-type.err
 create mode 100644 tests/qapi-schema/alias-name-bad-type.json
 create mode 100644 tests/qapi-schema/alias-name-bad-type.out
 create mode 100644 tests/qapi-schema/alias-source-bad-type.err
 create mode 100644 tests/qapi-schema/alias-source-bad-type.json
 create mode 100644 tests/qapi-schema/alias-source-bad-type.out
 create mode 100644 tests/qapi-schema/alias-source-elem-bad-type.err
 create mode 100644 tests/qapi-schema/alias-source-elem-bad-type.json
 create mode 100644 tests/qapi-schema/alias-source-elem-bad-type.out
 create mode 100644 tests/qapi-schema/alias-source-empty.err
 create mode 100644 tests/qapi-schema/alias-source-empty.json
 create mode 100644 tests/qapi-schema/alias-source-empty.out
 create mode 100644 tests/qapi-schema/alias-unknown-key.err
 create mode 100644 tests/qapi-schema/alias-unknown-key.json
 create mode 100644 tests/qapi-schema/alias-unknown-key.out
 create mode 100644 tests/qapi-schema/aliases-bad-type.err
 create mode 100644 tests/qapi-schema/aliases-bad-type.json
 create mode 100644 tests/qapi-schema/aliases-bad-type.out

-- 
2.29.2

Kevin Wolf <kwolf@redhat.com> writes:

> This series introduces alias definitions for QAPI object types (structs
> and unions).
>
> This allows using the same QAPI type and visitor even when the syntax
> has some variations between different external interfaces such as QMP
> and the command line.
>
> It also provides a new tool for evolving the schema while maintaining
> backwards compatibility (possibly during a deprecation period).
>
> The first user is intended to be a QAPIfied -chardev command line
> option, for which I'll send a separate series. A git tag is available
> that contains both this series and the chardev changes that make use of
> it:
>
>     https://repo.or.cz/qemu/kevin.git qapi-alias-chardev-v2

I'm done.  Summary:

PATCH 1: Update to the big comment is still missing, but we can do that
last.  I also flagged a possible contract clarification.

PATCH 2: Nits.

PATCH 3: Commit message questions.

PATCH 4: This one gave me trouble, and I feel unable to summarize.  I'm
afraid you have to wade through my review to answer questions and
address issues as far as practical.  And then we try again with v3.

PATCH 5: Documentation tweaks.

PATCH 6: Please consider adding more positive tests, as discussed in
review of PATCH 5.