`std::variant` is the last archetypal container missing in TreeBuilder-v2. The
code for it isn't hugely complicated and relies on pack expansion.
This change introduces a new field to the container specification:
`scoped_extra`. This field allows you to write extra code that will be included
within the TypeHandler in CodeGen. This means it will not have collisions with
other containers, unlike the existing `extra` field. It's used here to write
the recursive `getSizeType` function for `std::variant`.
Tech debt is introduced here by comparing the container name to `std::variant`
in CodeGen to conditionally generate some code. We've worked hard to remove
references to containers in code and move them to `.toml` files. On balance,
this is worth having to include the example of `std::variant`. It should be
moved into a container spec field at some point, the design of which is still
to be determined.
Test plan:
- Activated the OIL `std::variant` tests.
- CI
Summary:
Currently there are two features between CodeGen v2 (TypeGraph) and TreeBuilder
v2. These are TypedDataSegment and TreeBuilderTypeChecking. Each of these
features currently has a full set of tests run in the CI and each have specific
exclusions.
Collapse these features into TreeBuilder v2. This allows for significantly
simplified testing as any OIL tests run under TreeBuilder v2 and any OID tests
run under TreeBuilder v1.
The reasoning behind this is I no longer intend to partially roll out this
feature. Full TreeBuilder v2 applies different conditions to containers than
the intermediate states, and writing these only to have them never deployed is
a waste of time.
Test Plan:
- it builds
- CI
Summary:
Adds the option for required features to container definitions. These cause the container not to be passed to `DrgnParser` if that feature is not enabled during code generation. The thrift isset type does not currently work with `tree-builder-v2` and only provides benefit with `capture-thrift-isset`. This change makes sure the container is ignored if it won't be useful, allowing code generation under `tree-builder-v2`.
Test Plan: - CI
Differential Revision: D49960512
Pulled By: JakeHillion
This change is fully backwards compatible with the old ContainerInfo
parser, as it is just adding new fields.
The old fields will continue to be used by legacy OICodeGen until that
is removed.
Also add a README to document the format.
