hakorune/docs/development/current/main/phase74-checklist.md

Phase 74: BindingId Infrastructure - Completion Checklist

Implementation Checklist ✅

Core Files

• src/mir/binding_id.rs created

  • BindingId(u32) struct with overflow protection
  • new(), next(), raw() methods
  • Display trait implementation
  • 5 unit tests (creation, next, display, ordering, overflow)

• src/mir/mod.rs updated

  • Added pub mod binding_id;
  • Re-exported pub use binding_id::BindingId;

• src/mir/builder.rs extended

  • next_binding_id: u32 field added
  • binding_map: BTreeMap<String, BindingId> field added
  • allocate_binding_id() method implemented
  • Initialization in MirBuilder::new()
  • 4 unit tests added (initialization, sequential, shadowing, parallel)

• src/mir/builder/vars/lexical_scope.rs updated

  • restore_binding: BTreeMap<String, Option<BindingId>> field added to LexicalScopeFrame
  • pop_lexical_scope() restores binding_map
  • declare_local_in_current_scope() allocates BindingIds

Documentation

• docs/development/current/main/phase74-bindingid-infrastructure.md

  • Architecture (ValueId vs BindingId)
  • Implementation details
  • Test strategy
  • Next steps (Phase 75-77)

• docs/development/current/main/PHASE_74_SUMMARY.md

  • Implementation summary
  • Test results
  • Key design decisions

• docs/development/current/main/phase74-checklist.md (this file)

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Test Results ✅

Unit Tests (9 total)

$ cargo test --lib binding_id
test mir::binding_id::tests::test_binding_id_creation ... ok
test mir::binding_id::tests::test_binding_id_next ... ok
test mir::binding_id::tests::test_binding_id_display ... ok
test mir::binding_id::tests::test_binding_id_ordering ... ok
test mir::binding_id::tests::test_binding_id_overflow - should panic ... ok
test mir::builder::binding_id_tests::test_binding_map_initialization ... ok
test mir::builder::binding_id_tests::test_binding_allocation_sequential ... ok
test mir::builder::binding_id_tests::test_shadowing_binding_restore ... ok
test mir::builder::binding_id_tests::test_valueid_binding_parallel_allocation ... ok

test result: ok. 9 passed; 0 failed; 0 ignored

Regression Tests

$ cargo test --release --lib
test result: ok. 958 passed; 0 failed; 56 ignored

$ cargo test --features normalized_dev --test normalized_joinir_min
test result: ok. 54 passed; 0 failed; 0 ignored

Build Success

$ cargo build --lib
Finished `dev` profile [unoptimized + debuginfo] target(s) in 12.76s

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Acceptance Criteria ✅

Criterion	Status	Evidence
cargo build --lib succeeds	✅	Compiled without errors
cargo test --release --lib passes	✅	958 tests passed
cargo test --features normalized_dev --test normalized_joinir_min passes	✅	54 tests passed
New tests all pass	✅	9/9 BindingId tests passed
No production impact	✅	Infrastructure-only, no behavior changes
Phase 73 PoC structure replicated	✅	Same design as PoC, integrated into main

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Design Validation ✅

Architecture Principles

• Parallel Allocation: ValueId and BindingId independent
• Determinism: BTreeMap used (Phase 25.1 consistency)
• Symmetric Restoration: Both maps restored on scope exit
• Overflow Protection: debug_assert! checks in critical paths

Phase 73 Compatibility

• BindingId type matches PoC design
• allocate_binding_id() API matches PoC
• Lexical scope integration matches PoC
• Test strategy follows PoC validation

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Code Quality ✅

Documentation

• All public APIs documented
• Architecture overview written
• Examples provided
• Migration roadmap defined

Testing

• Unit tests for BindingId type
• Integration tests for MirBuilder
• Shadowing edge cases tested
• Parallel allocation verified

Code Style

• Follows existing MirBuilder patterns
• Consistent with Phase 25.1 BTreeMap usage
• Clear variable names
• Proper error messages

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Next Steps (Phase 75)

Pilot Integration Planning

• Identify 1-2 candidate files for pilot usage
• Design logging strategy (e.g., NYASH_BINDING_TRACE=1)
• Create pilot smoke tests
• Document pilot integration approach

Suggested Pilot Components

1. src/mir/builder/vars/ - Local variable tracking (high shadowing frequency)
2. src/mir/builder/stmts.rs - Statement lowering (control flow + shadowing)

Pilot Success Criteria

• BindingId used in 1-2 isolated components
• Logging shows correct BindingId allocation/restoration
• Smoke tests pass with pilot integration
• No behavior changes observed

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Commit Message Template

feat(mir): Phase 74 - BindingId infrastructure

Establish parallel BindingId allocation system alongside ValueId to support
future ScopeManager migration (Phase 75+).

Changes:
- Add src/mir/binding_id.rs (BindingId type + 5 tests)
- Extend MirBuilder with binding_map and allocate_binding_id()
- Update lexical_scope.rs for parallel restoration
- Add 4 integration tests in builder.rs
- Document architecture and migration roadmap

Test results:
- 9 new unit tests (all pass)
- 958 lib tests (no regressions)
- 54 normalized JoinIR tests (no regressions)

Phase 74 complete ✅ - Ready for Phase 75 pilot integration

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Sign-off

Phase 74 Implementation: ✅ Complete Test Coverage: ✅ Full (9 unit + existing smoke) Documentation: ✅ Comprehensive (~500 lines) Production Impact: ✅ Zero (infrastructure-only) Ready for Phase 75: ✅ Yes

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Date: 2025-12-13 Reviewer: (awaiting review) Status: Ready for integration