WebIR / HIR split-brain inventory (2026)

WebIR / HIR split-brain inventory (2026)

This document is the baseline split-brain map for the WebIR/HIR unification compare-both ADR. It lists where semantics are duplicated, bridged, or owned by a single projection so follow-up work can remove drift without guessing.

Pipeline shape (authoritative)

Stage	Crate / module	Role
AST → HIR	vox-compiler / hir::lower	Typed module shape (HirModule), migration fields, endpoints, reactive components.
HIR → WebIR	vox-codegen / web_ir::lower	lower_hir_to_web_ir — routes, styles, behaviors, DOM arena + view_roots.
WebIR validate	vox-codegen / web_ir::validate	Structural + a11y + route contract gates (VOX_WEBIR_VALIDATE, default on).
HIR → TS (legacy compat)	vox-codegen / codegen_ts::hir_emit	emit_hir_expr / JSX string emit; must stay aligned with web_ir::emit_tsx attribute matrix (hir_emit::compat, web_ir::primitives).
HIR → TS (reactive bridge)	vox-codegen / codegen_ts::reactive	WebIR emit_component_view_tsx is canonical for view:; emit_hir_expr is parity-only; blocking WebIR issues fail fast (see ReactiveViewBridgeStats).
HIR → AppContract	vox-compiler / app_contract	HTTP + @endpoint surface (also bundle.app via projection_bundle).
HIR → RuntimeProjection	vox-compiler / runtime_projection	DB plan snapshots + task capability hints (explicitly not WebIR); also bundle.runtime.
HIR → ShellProjection	vox-compiler / shell_projection	Typed @back_button / @deep_link / @push mirror consumed as bundle.shell (e.g. mobile_emit).
HIR → RequiredRuntimeCapabilities	vox-compiler / required_capabilities	Sorted capability id set for packaging (bundle.capabilities → Tauri projection subset in vox compile).
HIR → mobile.ts	vox-codegen / codegen_ts::mobile_emit	Emits from ShellProjectionModule (not raw HirModule fields).
Tauri packaging	vox-tauri-codegen	tauri.conf.json hints under target/generated/tauri-packaging/; see packaging SSOT.

Dual-path / parity hotspots

1. Reactive view: — WebIR canonical (legacy fallback removed)

• Files: crates/vox-codegen/src/codegen_ts/reactive.rs, crates/vox-codegen/src/web_ir/emit_tsx.rs, crates/vox-codegen/src/codegen_ts/hir_emit/mod.rs.
• Mechanism: Validated WebIR view TSX is always selected for the emitted return; emit_hir_expr runs only to classify parity (WebIrViewEmitted vs WebIrViewEmittedParityMismatch). Blocking validate_web_ir diagnostics or missing Web IR view roots fail fast (placeholder return + reactive_view_emit_failures).
• Risk: Divergence in JSX attribute names, primitive kwargs (web_ir::primitives vs transform_hir_view_kwargs), or handler await threading.
• Mitigation in tree: Shared map_jsx_attr_name, expand_bind_hir_attribute / lower_jsx_attr_pair, transform_hir_view_kwargs used from web_ir::lower.
• Tests: crates/vox-compiler/tests/reactive_smoke_test.rs (reactive_codegen_uses_webir_canonical_view), web_ir_lower_emit_test.rs, integration pipeline tests.

2. Route manifest — WebIR-first

• Files: crates/vox-codegen/src/codegen_ts/route_manifest.rs (WebIrModule route trees; comment // Source: WebIR RouteTree → TS).
• Risk: Low if lower_hir_to_web_ir is the single route-tree source; HIR-only route emitters must not bypass WebIR for manifest rows.

3. Mobile / shell primitives — ShellProjection + required capabilities

• Files: crates/vox-codegen/src/codegen_ts/mobile_emit.rs, crates/vox-compiler/src/shell_projection.rs, crates/vox-compiler/src/required_capabilities.rs, crates/vox-compiler/src/hir/nodes/decl.rs (HirFieldOwnership::Shell for back_button / deep_link / push).
• Risk: Packaging permissions drifting from actual module needs.
• Mitigation: RequiredRuntimeCapabilities drives a filtered runtime-capabilities.projection.json on vox compile (full YAML mirror when no HIR is available, e.g. vox init templates).

4. Tauri Rust command path — stub only

• Files: crates/vox-codegen/src/codegen_rust/emit/tauri_stub.rs (banner only; Axum remains primary for @endpoint).
• Risk: Future #[tauri::command] emission must reuse the same capability resolution as web + mobile.

Anti–split-brain guards (tests)

Test / artifact	What it proves
crates/vox-compiler/tests/projection_parity_test.rs	Bundle + per-projection canonical bytes are deterministic; bundle fixture asserts distinct hashes and expected capability_ids; @back_button fixture guards shell + triplet stability.
web_ir_lower_emit_test.rs	Lower + validate + serde round-trip + validator edge cases.
reactive_smoke_test.rs	reactive_codegen_uses_webir_canonical_view (non-ignored) pins Path C WebIR emit + bridge stats.
vox-arch-check [[forbidden_pattern]] (projection-bundle-*-emit-boundary in layers.toml)	Bans direct lower_hir_to_web_ir / project_* in codegen_ts/** and codegen_rust/** outside projection_bundle.rs.
web_ir_environment_gates_test.rs	VOX_WEBIR_VALIDATE fail-closed behavior.

Quantitative grep anchors (maintenance signal)

Rough reference counts under crates/vox-codegen (subject to churn):

• emit_hir_expr — concentrated in hir_emit/mod.rs (compat string emitter + WebIR lowering helper).
• lower_hir_to_web_ir / validate_web_ir — web_ir/*, emitter.rs, build.rs, integration pipeline.
• Interpretation: Unification is not “delete WebIR calls” until hir_emit JSX paths are retired or folded behind a single printer; see ADR Option B recommendation.

Related

• Explanation: Compiler lowering phases
• ADR 012 — Internal web IR strategy (historical rationale; superseded pointers in ADR header)
• ADR 036 — WebIR/HIR unification compare-both
• Vox application packaging SSOT (2026)