Additional flatc compatibility: bit flags, arrays of scalars in structs, and file identifiers. #366
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kraln wants to merge 5 commits into
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Additional flatc compatibility: bit flags, arrays of scalars in structs, and file identifiers. #366kraln wants to merge 5 commits into
kraln wants to merge 5 commits into
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Accept the (bit_flags) attribute on enums (unsigned underlying type, member value = 1 << position) and generate a dependency-free #[repr(transparent)] newtype with flag constants, bitwise operators and a decomposing Debug. Reads are infallible, so bit_flags enums flow through codegen like their underlying integer. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Struct fields may now be fixed-size arrays of scalars (e.g. [uint8:16]), generated as [T; N] with inline Primitive/WriteAsPrimitive impls so the elements are written contiguously inside the struct. Non-scalar element types are rejected with an error. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
A schema's file_identifier is attached to its root_type table and exposed as an IDENTIFIER associated constant, alongside a new planus::buffer_has_identifier helper. Builder::finish is also fixed to write the identifier into bytes 4..8 after the root offset (the two were previously swapped, on an untested path) so identifier-bearing buffers match the official implementation. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Fixed-size array struct fields are shown as an array whose children are the individual elements, and bit_flags values are decomposed into their set flags (e.g. Fault::A | Fault::C) instead of a single-variant lookup. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Update README.md, remove (now incorrect) "we don't support currently" - `file_extension`, `file_identifier` and `root_type` - Fixed-size arrays
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Howdy!
I have a system which makes extensive use of flatbuffers as an internal API surface for IPC (over NATS), and many of those services are transitioning to Rust. The official libraries are... not the best developer experience, and there were only a few features the system relies on that planus didn't support.
This MR implements those features (that were missing for my usecase), potentially it'd be useful for everyone else, too :-)
file_identifier/root_type: generate aIDENTIFIERassociated constant forthe root table and add a
planus::buffer_has_identifierruntime helperby
Builder::finish(.., Some(id))are byte-compatible with the official implementationAddresses #141 and #55.
[uint8:16])This was not currently tracked as an issue that I could find, but highlighted in the README.md (which is now updated to remove it, along with the file identifiers/root type)
(bit_flags)enums, generated as a dependency-free flags newtypeI guess this counts as an "exotic" type, which is now supported. The official rust library implements this with a crate dependency, but it seemed like that wouldn't be in-line with planus's goals.