2 Commits
Author SHA1 Message Date
Dario LipicarandClaude Opus 5 198f0317ca feat(optional): ?T is two-state, and the generators finally read it (#125)
* feat(optional): ?T is two-state, and the generators finally read it

No generator in any language read the optional flag — it had never been
implemented. `?T` was a HARD REJECT on the cdylib backend ("module not
cdylib-eligible"), `std::optional<T>` in an impl header fell through to the
opaque `any` with no diagnostic, and a `? name: T` field was emitted as a
required `T`. Three real contracts in the workspace already declare optionals
and were silently getting one of those three answers.

`?T` is TWO-state: a value of T, or empty. Never three — "one LIDL type <-> one
type per language" leaves nowhere for a third state, because every target has
exactly one empty inhabitant.

ONE MEANING, TWO SPELLINGS. `? name: T` (the field flag) and `name: ?T` (the
type kind) are the same declaration. Backends no longer answer that themselves:
logos-lidl's fieldIsOptional/fieldValueType are re-exported from lidl_compat.h
and every site THIS COMMIT TOUCHES reads them, so the two spellings emit
byte-identical code on the cdylib and client backends. That
caught a live drift on the way in — lidlRecordCollidesWithBytesTag read `f.type`
and so refused `? _bytes: tstr` while letting `_bytes: ?tstr` straight through,
one declaration with two answers.

THE WIRE RULE DEPENDS ON THE SLOT. Absent and explicit null are the SAME state
on decode and DIFFERENT on encode:
  - decode is liberal, by exactly one inhabitant: in an optional slot absent and
    null both mean empty; in a required slot both stay errors. A present value
    goes through the decoder a required T would get, so a wrong type still fails
    at the same path — optional widens the domain, it does not switch checking
    off. `?bstr` therefore keeps the LENIENT bytes decode a bare `bstr` gets,
    rather than silently becoming stricter in the optional slot.
  - encode has one canonical form: empty OMITS the key where the slot is NAMED
    (a record field) and is spelled null where it is POSITIONAL (an argument, a
    return, an event parameter — no key to omit, and arity must not change). Key
    omission lives in the record emitter because a Codec only ever sees a value,
    never the slot it sits in. A round trip therefore canonicalises.
  - `?any` collapses onto `any`: nlohmann::json already carries null, so
    std::optional<LogosMap> would give the slot two spellings of empty.

The dispatch gate now admits a missing trailing optional argument and
materialises it as null, exactly the way a missing record field already was. A
method with no optional parameter emits the byte-identical gate it always did.

Header-first: `std::optional<T>` <-> `?T`, composing with records and
containers. `std::optional<std::optional<T>>` has NO LIDL type (three C++ states
over a two-state wire), so it maps down to `?T` — which makes the author's own
declaration stop compiling against the generated codec, deliberately — and says
so at derivation time instead of leaving a conversion error in generated code.

The Qt/Lp consumer surface is NOT fixed and does not pretend to be. The wrappers
real modules get come from legacy/main.cpp, where the AST is flattened to a
single Qt type-name string per slot before optionality could be seen; Qt has no
optional metatype, so `?T` lands on QVariant — the right shape (an invalid
QVariant is Qt's empty inhabitant) with no type. The generator now prints a Note
naming every flattened slot so an affected build is never silent, and
docs/project.md records exactly what a Qt consumer will still do with an
optional field.

Verified by output equivalence, not by a green build: the generator was built
before and after and run over every .lidl in the workspace plus the impl-header
fixtures, in cdylib, consumer-qt, consumer-lp, client and header-first modes.
428 of 465 artefacts are byte-identical; all 37 that differ belong to one of the
four contracts that declare an optional (the 38th path is the manifest). The
harness's sensitivity is pinned by a negative control: qt vs lp output differs
in 45 files. The emitted codec was additionally compiled under -Wall -Wextra and
run against the rules above — omission, absent==null, required-still-rejects,
present-but-wrong-still-fails, and canonicalising round trip.

Tests: 199 pass, 0 fail (180 before, 19 new).

Requires logos-lidl's optionality accessors and logos-protocol's
Codec<std::optional<T>>.

NOT FIXED, AND IT IS THE PATH THAT MATTERS MOST. The legacy interface-wrapper
path is untouched, and it is the one every real module builds through
(buildPlugin.nix:145 -> logos-cpp-generator --general-only). There the two
spellings still diverge:

  ? maybe: tstr   ->  QString maybe{};   __m.value("maybe").toString()
  maybe: ?tstr    ->  QVariant maybe{};  __m.value("maybe")

and --api-style lp diverges too, neither side being std::optional. So R3 holds
on the backends below and NOT on the Qt consumer a shipping module actually
gets. logos-chat-module -- the contract that prompted this work -- uses the
field-flag spelling, so it lands on the branch that silently defaults.

The cause is upstream of codegen: legacy/main.cpp's moduleRecordsToJson and
moduleMethodsToJson flatten every TypeExpr to a single Qt TYPE-NAME STRING, so
optionality (along with nesting, map key types and descriptions) is gone before
generator_lib.cpp sees it. Widening that interface is a larger change and is
deliberately not attempted here. The only R3 test on a Qt surface covers
lidl_gen_client.cpp, which is on no live build path.

* chore: re-pin logos-lidl to master for the optionality accessors

lidl_compat.h re-exports typeIsOptional / optionalValueType / fieldIsOptional /
fieldValueType / paramIsOptional / paramValueType, which landed in
logos-lidl#7. The pinned lidl predated it, so CI failed to compile.

logos-lidl 8c95d4f -> 35f33d8. Tests: 199 pass, 0 fail.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

* chore: re-pin logos-protocol to master for Codec<std::optional<T>>

The generated record codecs emit Codec<std::optional<T>> for an optional
field; that specialisation landed in logos-protocol#37 and the pinned
protocol predated it.

Note this repo's own tests would NOT have caught the omission -- the
generator tests string-assert emitted text rather than compiling it, so a
missing codec specialisation only surfaces when a real module compiles
generated optional code (logos-test-modules' ext provider).

logos-protocol 4359557 -> 72754ab. Tests: 199 pass, 0 fail.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

* test(doctests): override logos-lidl alongside every logos-cpp-sdk override

The doc-tests build downstream repos (logoscore-cli, capability_module,
accounts_module) with --override-input logos-cpp-sdk. Nix does not carry the
overridden input's OWN lock, so those builds got this branch's cpp-sdk source
while still resolving logos-lidl from their own, older locks. The shipped
share/lidl-frontend/lidl_compat.h then calls accessors that lidl does not
have:

  lidl_compat.h:46: error: 'paramValueType' has not been declared in 'lidl'
  lidl_compat.h:92: error: 'fieldValueType' was not declared in this scope

Every --override-input logos-cpp-sdk now has a matching
--override-input <same-path>/logos-cpp-sdk/logos-lidl.

This is specific to the override path. A normal consumer running
'nix flake update logos-cpp-sdk' inherits cpp-sdk's own lock, which pins the
lidl carrying these accessors, and is unaffected.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

* test(doctests): move logos-lidl at the qt-sdk nodes, not under logos-cpp-sdk

The doc-tests failed to build logos-qt-generator:

  share/lidl-frontend/lidl_compat.h:46: error: 'paramValueType' has not been
  declared in 'lidl'

MECHANISM. This SDK installs cpp-generator/experimental/lidl_compat.h into
$out/share/lidl-frontend/, and logos-qt-sdk's logos-qt-generator *compiles*
that installed header against qt-sdk's OWN logos-lidl input. Under
logos-qt-sdk, logos-lidl is a SIBLING of logos-cpp-sdk, not a descendant:

  logos-qt-sdk
  |-- logos-cpp-sdk   <- --override-input moves this to the commit under test
  `-- logos-lidl      <- stays on qt-sdk's lock (8c95d4f), lacks the accessors

logos-logoscore-cli and logos-module-builder both declare
`logos-qt-sdk.inputs.logos-cpp-sdk.follows = "logos-cpp-sdk"` but no lidl
follows, so overriding the SDK hands qt-sdk a new lidl_compat.h next to its
old lidl. The failing derivation is logos-qt-generator — not anything in
logos-cpp-sdk, which is why the previous attempt aimed at the wrong node.

THE FIX is one `<path-to-logos-qt-sdk>/logos-lidl` override per qt-sdk node
that ends up on the SDK under test. A tree-walk over the resolved lock found
four in logoscore-cli's closure and two per module build; with the overrides
applied the walk reports zero remaining.

WHAT WAS REMOVED, and why it was doing nothing:

  * The `.../logos-cpp-sdk/logos-lidl` overrides added in bef3ef5 were no-ops.
    With only `--override-input logos-cpp-sdk <sha>`, that node's logos-lidl
    already resolves to 35f33d87 out of cpp-sdk's own lock — nix >= 2.26
    carries an overridden input's lock, and CI runs Determinate Nix. Verified
    by resolving the lock with and without them: byte-identical.
  * The `logos-module-client/...` overrides never matched anything. Nix says so
    out loud ("does not match any input"): logoscore-cli has no such root
    input; module-client only appears under logos-test-modules/, outside the
    runtime closure. The prose claiming it pins the SDK is corrected too.

cpp-sdk-concurrent-dispatch is fixed here as well — it failed the same way and
carried no lidl overrides at all.

VERIFIED locally against bef3ef5, the exact commit CI failed on:

  * accounts .lgx  -> exit 0, logos-accounts_module-module-lib.lgx (5,939,898 B)
  * logoscore CLI  -> exit 0, ./logos/bin/logoscore reports
                      "logos-cpp-sdk bef3ef57d3f489073672e70a786c550df7edd003"
  * negative control (same command minus the single qt-sdk lidl flag) fails
    with CI's exact derivation,
    /nix/store/pf96n2ldvhy6sq39ygkh5zdqx7dcn4df-logos-qt-generator-0.1.0.drv
  * no "does not match any input" warnings remain on any command

The durable fix is a one-line bump of logos-qt-sdk's own flake.lock logos-lidl
to master (logos-lidl#7 is purely additive: six new inline helpers, nothing
removed or renamed). Once qt-sdk carries it, every override added here can go.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
2026-07-31 07:19:47 -03:00
Dario LipicarandClaude Opus 4.8 aea29d3797 Per-module concurrent dispatch: C++ module async export (#93)
* feat: emit logos_module_dispatch_async for concurrency:multi C++ modules

The cdylib C-ABI exports gain an async dispatch entry (each call run on a worker
thread, reply on completion) for universal + cdylib C++ modules. --concurrency
multi flag in logos-cpp-generator.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* docs: cpp-sdk concurrent-dispatch doctest (concurrency:"multi" showcase)

A concurrency:multi C++ worker + a single driver firing concurrent calls, showing
the multi worker overlaps them. The C++ cdylib generator needs NO change — its
logos_module_dispatch is already safe to call concurrently; the worker pool lives
in the Qt glue and the result is deferred via a sentinel + completion event.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* fix: wire universal-cdylib modules() independent of the context latch

A C++ interface:"universal" cdylib that calls another module via
modules().<dep>... segfaulted on its FIRST cross-module call: the typed
dependency surface (LogosModules) was wired inside lidlTryFireContext, which
returns early when no persistence context was stored (g_ctxStored == false).
When the daemon never delivers a context (observed: zero set_context calls for
a context-less module), maybeSetLogosModules never ran, m_logosModulesPtr
stayed null, and LogosModuleContext::modules() dereferenced null.

modules() does not need the context — each dependency client bakes its
target+origin at codegen time and creates its lp client lazily on first call.
So wire it in its own context-independent once-latch (lidlEnsureModulesWired),
called at the top of lidlTryFireContext before the context-gated early return,
i.e. on the first dispatch / set_context / set_emit_callback. A module with
deps but no stored context now has modules() wired before any handler runs.
(Bump the concurrent-dispatch doctest's post-daemon-start sleep 3 -> 6 to match
the rust spec's cold-start margin.)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* test: green the universal-cdylib concurrent-dispatch doctest + wire into CI

The driver/worker split a declarations-only impl header (so the cpp-generator's
--header-to-lidl doesn't choke on inline std calls) from the impl body. That
body was never compiled — metadata's nix.cmake.extra_sources is parsed but not
consumed by the LogosModule.cmake the build actually uses — so the impl symbols
(FanoutDriverModuleImpl::fanOut / ::peak) were UNDEFINED in the dylib and the
plugin null-jumped (bl -> 0x0) on the first cross-module call. Pass the impl
.cpp via logos_module()'s existing SOURCES argument so it's compiled and linked.

With this the cpp universal-cdylib reaches worker peak overlap 4 end-to-end (a
single-threaded driver fans out 4 async calls into a concurrency:"multi" worker
and all four overlap), matching the Rust half. Wire the spec into doctests.yml
so the workspace pipeline runs it.

(Auto-wiring metadata.extra_sources — so the split pattern works without listing
SOURCES by hand — needs the consumer added to the backend LogosModule.cmake
copies in logos-plugin-core / logos-plugin-qt; tracked separately.)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* chore: bump logos-protocol to merged master (protocol#5)

  logos-protocol  9de4165 → 4ea32a3  (concurrent-dispatch handshake coalescing, now on master)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-19 16:31:45 -03:00