Implementation half of the Phase 3.1 cadence step.
`lowerForeignStaticCall` for `#objc_class` / `#objc_protocol` runtimes
no longer bails; it routes through a new `lowerObjcStaticCall` helper
that loads the class object from a module-scoped cached slot (populated
once per module via `objc_getClass`) and dispatches `objc_msg_send`
with the same selector-mangling as Phase 3.0's instance dispatch.
Three pieces:
1. `Module.objc_class_cache` — parallel to `objc_selector_cache`,
insertion-ordered list of (class_name, slot_GlobalId) so the
constructor that calls `objc_getClass` per slot at module load
is deterministic. `lookupObjcClass` / `appendObjcClass` accessors.
2. `internObjcClassObject` in lower.zig — get-or-create a
`OBJC_CLASSLIST_REFERENCES_<Cls>` global pointer; matches clang's
naming convention. `lowerObjcStaticCall` reuses
`deriveObjcSelector` from 3.0 for the selector, loads the class
slot, and emits `objc_msg_send(class_obj, sel, args)`.
3. `emitObjcClassInit` in emit_llvm.zig — companion to
`emitObjcSelectorInit`. Walks `objc_class_cache`, synthesizes a
constructor `__sx_objc_class_init` that calls `objc_getClass(name)`
per slot, registers in `@llvm.global_ctors` for AOT (extending the
existing array if the selector init already created it), and
injects a direct call into main's prelude after any prior init
calls so the ORC JIT path runs it too.
Surface form is `.` (`NSObject.class()`) matching JNI's `Alias.new(...)`
convention rather than the plan's notional `::` — avoids extending the
parser for a new postfix operator with no other use case.
Test `examples/ffi-objc-dsl-05-static.sx` exercises NSObject's
`+class` and `+description` class methods via the new syntax, asserts
both return non-null. NSObject is always available at module-load,
unlike runtime-created test classes that wouldn't exist yet when
the class-init constructor runs.
164/164 tests; chess builds + runs clean on all three platforms.
Implementation half of the cadence step started in the previous commit.
`lowerForeignMethodCall` for `#objc_class` / `#objc_protocol` runtimes
no longer bails; it routes through a new `lowerObjcMethodCall` helper
that derives the Obj-C selector from the sx method name and lowers to
`objc_msg_send` against the cached SEL slot (same intern path as
explicit `#objc_call`).
Default selector mangling (matches clang's keyword-method convention):
- Niladic (arity 0 excluding self): name verbatim. `length()` → "length".
- Arity ≥ 1: split the sx method name on `_`; each piece becomes a
keyword with a trailing `:`. `addObject(o)` → "addObject:";
`combine_and(a, b)` → "combine:and:";
`initWithFrame_options(f, o)` → "initWithFrame:options:".
Arity validation: keyword count (pieces from the `_`-split) must equal
call-site arity excluding self. Mismatch diagnoses at the call site
with a hint pointing at the forthcoming `#selector("...")` override
(Phase 3.2) for selectors that don't fit the underscore-split rule.
Mangling helper `deriveObjcSelector` and dispatch helper
`lowerObjcMethodCall` sit alongside `lowerForeignMethodCall`. The
existing fall-through diagnostic for non-JNI/non-Obj-C runtimes
remains for Swift (Phase 4 territory).
Tests `examples/ffi-objc-dsl-{01-niladic,02-one-arg,03-multi-keyword,
04-mismatch}.sx` snapshots flip from the pre-3.0 bail diagnostic
(exit=1) to working output (exit=0 for cases 01-03) and the specific
keyword-count mismatch diagnostic for case 04. Each test follows the
established pattern from `ffi-objc-call-08-multi-keyword.sx`:
synthesize a class at runtime via `objc_allocateClassPair` /
`class_addMethod`, declare a matching `#objc_class`, invoke the DSL
form. 163/163 tests; chess unaffected (JNI dispatch path untouched).
The previous FFI checkpoint claimed Phase 3 step 3.0 ("`inst.method(args)`
on #objc_class receivers") had landed. It hadn't — `lowerForeignMethodCall`
in lower.zig:4353 still bails for any non-JNI runtime with the generic
"method calls on '{runtime}' runtime not yet supported (Phase 3/4)"
diagnostic, no commit introduced an Obj-C DSL dispatch path, and the
planned regression files weren't on disk.
This commit is the xfail half of the proper cadence (test-add then
make-green in separate commits):
- examples/ffi-objc-dsl-01-niladic.sx — `length()` → selector "length".
- examples/ffi-objc-dsl-02-one-arg.sx — `addObject(o)` → "addObject:".
- examples/ffi-objc-dsl-03-multi-keyword.sx — `combine_and(a, b)` →
"combine:and:" (sx name split on `_`, each piece becomes a keyword
with a trailing `:`).
- examples/ffi-objc-dsl-04-mismatch.sx — `something_extra(x)` —
keyword count (2) ≠ arity (1); must diagnose at the call site.
Each test follows the same pattern as `ffi-objc-call-08-multi-keyword.sx`:
synthesize a class at runtime via `objc_allocateClassPair` /
`class_addMethod`, declare the sx-side `#objc_class` against the same
name, then invoke the DSL form. Skips with a "(not macos)" line on
non-macOS hosts. Snapshots currently lock in the bail diagnostic with
exit=1; the next commit implements the dispatch and the snapshots
flip to the working output (and exit=0).
Checkpoint corrected to flag the prior false claim and reposition 3.0
back at the top of the open list.
