# Changelog ## 2026-04-10 - **P0-ZIG-CREXC-S4 complete**: Zig / Rust exception / try / with / raise handling fully shared via CommonRenderer hooks. Most language-specific duplication removed from emitters. - **Zig toolchain_ dependency removed**: `toolchain_.frontends.runtime_symbol_index` dependency eliminated. All toolchain_ dependencies now gone (Dart / Swift / Julia / Zig). - **Zig new fixture parity verified**: with_statement / with_context_manager and other new fixtures pass on Zig. - **Nim parity complete**: P1-NIM-EMITTER-S5/S6 done. Compile/run parity established; fixed index errors in new fixtures. - **Go type-id helper dependency removed**: P0-GO-TYPEID-CLN-S1~S3. Legacy type-id helper gone from Go emitter. - **Lua emitter guide violations fixed**: P0-LUA-EMITGUIDE-S1~S3. Hardcode removal, mapping-driven lowering. - **Lua full fixture parity complete**: P1-LUA-EMITTER-S5 done. - **P3-COPY-ELISION-S4 Lua implementation complete**: `bytes(bytearray)` copy elision in Lua runtime. Readonly proof extended across modules. png/gif copy elision path finished. ## 2026-04-09 - **P0-ZIG-CREXC-S4 continued**: Shared Zig / Rust handler binding, bound exception value builder, slot accessor, with fallback protocol calls via hooks. Rust with helpers (entry/exit target, exit action, bind cloning, close fallback, protocol call builder, hoist collection, enter/exit metadata helpers) migrated to CommonRenderer. - **Rust panic hooks**: `panic_any`, panic capture wrapper, panic raise rendering routed through hooks. - **Zig block expression helper sharing**: Compare block, comprehension block, guarded inline exception block, simple block expr helpers consolidated in CommonRenderer. ## 2026-04-08 - **All languages lint clear (0 violations)**: Down from 697 on Apr 4. 18 languages at 10/10 PASS. - **C# / Go / Nim parity + stdlib parity restoration**: Migration to metadata-driven lowering, runtime metadata alignment. - **Import binding unified**: std / helper symbol imports resolved via mapping.json. - **Fixture gaps closed**: PS1 / Go / Nim fixture parity gaps filled. - **Zig fixture parity restored**: Aligned with semantics. - **P0-ZIG-CREXC S1-S3 started**: Plan to push Zig / Rust exception handling (raise / try / with) into CommonRenderer. Rs/zig user-context with, raise/try shape classification, try handling shared. - **P0-ZIG-CREXC-S4 started**: Rs/zig exception style declared in emit profiles. Handler type/body/name access, handler dispatch loop, try match wrapper, string/user handler chain routed through hooks. - **Nim emitter string-split workaround removed**: `"po" + "p"`, `"o" + "s"` etc. lint-avoidance tricks eliminated. Migrated to mapping-driven method lowering. - **PowerShell emitter guide alignment**: Aligned with with-metadata and runtime mapping. - **Rust emitter literal coupling removed**: String hardcode removed from emitter. - **Lint: non-emitter false positive exclusion**: Lint now excludes false positives from non-emitter files. ## 2026-04-07 - **Lint down to 149 / 14 languages at 10/10 PASS**: C++, JS, TS, Dart, Swift, Julia, Zig, Java, Scala, Kotlin, Ruby, Lua, PHP, Nim (Nim 9/10). Down from 697 on Apr 4. - **PyFile abolished**: Replaced fake `PyFile` type with Python's `io` module hierarchy: `IOBase` / `TextIOWrapper` / `BufferedWriter` / `BufferedReader`. Defined in `src/pytra/built_in/io.py` as `@extern class`. - **Emitter guide §12.7 file I/O type mapping**: Documented mode-based resolved_type, io.py hierarchy, naming conventions. Emitters must not branch on type name strings. Runtime implementations must match built_in/io.py names. - **Lint: PyFile detection**: `class_name` category detects `"PyFile"` in emitters. `rt:type_id` detects deprecated `PyFile` key in mapping.json types. - **Cross-language PyFile coupling removal**: Removed PyFile references from Java, Swift, Ruby, Lua, C++, TS, Julia emitters. - **Go / Rust / C# / PHP emitter guide alignment**: Mapping-driven method lowering, stale mapping cleanup, parity restoration. - **Ruby / Lua hardcode removal + parity restoration**: Emitter hardcode cleanup and stale mapping entries removed. - **JVM backend continued**: Java stdlib/sample parity restored. Kotlin emitter complete (sample 18/18 PASS). - **TODO cleanup**: Archived completed tasks for C++, Swift, Julia, TS, Dart, JVM. ## 2026-04-06 - **With statement via __enter__ / __exit__ protocol**: CommonRenderer default try/finally + hoist. C++ parity PASS. Plan in `p0-with-context-manager.md`. - **With fixtures**: `with_statement` (file I/O) and `with_context_manager` (user-defined __enter__/__exit__ call order + exception safety). - **Parity check: keep work dir on FAIL**: Failed cases now print `[INFO] work dir kept for inspection: ` and preserve generated files. - **Progress summary regeneration fix**: Changed marker from `backend-progress-fixture.md` mtime to dedicated `.parity-results/.progress_generated`. - **pathlib_extended joinpath**: Added Path.joinpath() tests. Resolved Julia mapping-to-east coverage warning. - **.east* removed from git**: Untracked 12 files in test/include/east1/ and 1 in src/runtime/east/. Added to .gitignore. - **TS/JS shim cleanup complete**: Removed Python builtin shims (`int=Number` etc.) from py_runtime.ts/js. Emitter uses mapping.json. - **Dart emitter guide compliance**: Removed toolchain_ dependency. Module-prefix hardcode removal, metadata-based method lowering/ctor/With support. - **JVM backend major progress**: Java/Scala/Kotlin mapping.json canonicalization, fixture parity restoration. Scala/Kotlin emitters implemented. Stdlib/sample parity restored. - **C++ / Swift / Julia / Dart with fixture support**: Each language passes with_statement fixture. - **P2-*-LINT policy unified**: All languages' lint tasks now focus on emitter guide compliance, not just zero violations. ## 2026-04-05 - **containers.py mut[T] annotations**: Defined container method signatures as source of truth in `src/pytra/built_in/containers.py`. Resolve derives `meta.mutates_receiver: true` from `mut[T]`. - **C++ method name hardcode removed**: Replaced mutable method name lists in emitter.py/header_gen.py with `meta.mutates_receiver`. Lint runtime_symbol 0. - **C++ mapping.json cleanup**: Classified and removed 14 dead entries. rt:call_coverage 0. - **C++ new fixture parity**: bytes_copy_semantics, negative_index_comprehensive, callable_optional_none, str_find_index, eo_extern_opaque_basic, math_extended, os_glob_extended all PASS. - **mapping.json FQCN key unification**: All languages' mapping.json calls keys unified to fully qualified names. - **Toolchain rename complete**: toolchain → toolchain_, toolchain2 → toolchain. toolchain_ gitignored. - **New fixtures**: str_count, sorted_basic, exception_types, float_constructor. ## 2026-04-04 - **Lint: Python method name hardcode detection**: Added 23 patterns ("append", "extend", "pop", "clear" etc.) to runtime_symbol category. - **Parity check: all-skip now FAIL**: Cases where all targets skip (missing toolchain) now report FAIL, not false PASS. Fixes Kotlin/Scala/PowerShell. - **pytra-cli.py default output → work/tmp/**: No more stray .east files in source directories when -o is omitted. - **Removed auto-lint from parity check**: Lint runs manually or via run_local_ci only. - **Lint always 10 categories**: --include-runtime default ON, replaced with --skip-runtime. Cache mechanism removed. - **callable_optional_none fixture**: Tests callable|None is-None guard + invoke. C++/Rust optional callable unwrap fixed. - **Emitter guide §12.6 callable mapping**: All languages' callable type mapping and callable|None representation documented. - **Emitter guide §14.1 lint docs**: All 10 categories explained, execution instructions added. - **mapping.json FQCN key plan**: Bare symbols ("sin") risk collision with user functions. Plan to use "pytra.std.math.sin" (P0-MAPPING-FQCN-KEY). - **Stray east file cleanup**: Removed from out/, src/include/, test/fixture/source/, test/stdlib/source/. - **Nim PyObj boxing rejected**: Must use object variants per spec-adt.md §3.1. - **Zig old toolchain edit reverted**: src/toolchain/emit/zig/ is read-only. - **Zig fixture/stdlib**: fixture 146/146 PASS, stdlib in progress. - **Julia fixture**: 116→145 (+29). PowerShell stdlib: 0→6 (+6). ## 2026-04-03 - **Unified emitter call structure**: New common runner `cli_runner.py`. 17 languages migrated (Rust only exception). `pytra-cli.py` calls cli.py via subprocess, no direct emitter imports. - **Parity check emit unification**: Replaced 18-language if/elif chain with importlib dynamic import + common loop. - **`resolved_type: "object"` banned globally**: EAST3 validator fail-fast. Trait `cls: object` → `@template T`, dict.get() type inference bug fixed. - **IsInstance PYTRA_TID_* removed**: Migrated to `expected_type_name`. C++ reverse lookup table deleted. - **`--east3-opt-level` → `--opt-level` rename**: Integrated negative_index/bounds_check preset. - **@extern class opaque type**: spec finalized, class_storage_hint:"opaque" + meta.opaque_v1. New `eo_` prefix for emit-only fixtures. - **builtin_name removed**: Deleted from EAST3 compile/resolve. mapping.json keys unified to runtime_call. - **runtime_call coverage lint**: New `rt: call_cov` category in emitter-hardcode-lint.md. - **Lint always 10 categories**: `--include-runtime` default ON. Removed auto-lint from parity check. - **All-skip now FAIL**: Parity check reports FAIL when all targets skip (missing toolchain). - **tools/unregistered/ deleted**: 110 retired scripts removed. - **check_todo_priority.py deleted**: Impractical priority checker removed. - **Julia / Zig / PowerShell / Swift / Dart backend TODOs**: Toolchain2 emitter tasks created for each. - **Kotlin / Scala merged into JVM backend TODO**: Managed in java.md. ## 2026-04-02 - **C++ monostate → optional\**: `T1 | T2 | None` mapping changed from `std::variant<..., std::monostate>` to `std::optional>`. Aligned with Rust `Option`. - **C++ bounds check / negative index → EAST optimizer**: Migrated to `subscript_access_v1` metadata. Sample 01 mandelbrot 12.8s → 0.82s. - **png.py / gif.py extend optimization**: Replaced append loops with extend. Speeds up PNG/GIF for all languages. - **bytes_copy_semantics fixture**: Verifies bytes(bytearray) makes independent copy. - **negative_index fixtures**: comprehensive + out_of_range. - **emitter guide §12.4-12.6**: Optional/union type mapping, callable type mapping for all languages. - **Emitter lint improvements**: runtime cache, total_cats denominator fix. - **Fixture rename**: any_* → union_*/optional_none. - **Java / C# tasks archived**. Badge order unified (JVM grouped). ## 2026-04-01 - **Emitter lint runtime cache**: --include-runtime results cached and restored on normal runs. - **Source-of-truth modification prohibition**: src/pytra/utils/*.py and src/pytra/std/*.py may not be modified by backend agents. - **EAST3 copy elision plan**: Planned copy_elision_safe_v1 metadata for bytes(bytearray) optimization. - **C++ prefix_match lint fix**: Removed pytra.std. fallback from runtime_paths.py. ## 2026-03-31 - **Ruby / Lua / PHP / Nim backend teams added**: TODO and plans created for each language. - **C# emitter pre-selfhost complete**: fixture 131/131 + sample 18/18 + stdlib 16/16 PASS. Lint all categories 0. Added dotnet fallback to parity check. - **C# / Java emitter progress**: Java S1/S2 complete. - **spec-python-compat: bool is NOT a subtype of int**: isinstance(True, int) returns False in Pytra. - **spec-emitter-guide §15 FAQ expanded**: unsigned right shift, package manager prohibition, type check skip prohibition, yields_dynamic cast guidance. - **spec-emitter-guide §13 selfhost parity**: Added `run_selfhost_parity.py` as canonical tool. Defined selfhost completion criteria (emit → build → golden → fixture parity → sample parity). - **spec-emitter-guide §1.1 new prohibition**: Banned per-arity tuple `in` specialization. Must use iterable generic contains. - **EAST3 narrowing Cast node**: Rust team implemented Cast node insertion after isinstance narrowing. - **EAST tuple unpack bugfix**: Fixed 3 patterns — parenthesized LHS `(x,y,z)=`, bracket LHS `[x,y,z]=`, comprehension + unpack. - **spec-east.md §4.1 Python → EAST node conversion table**: Comprehensive table for all categories (assignment/unpack, loops, functions/closures, control flow, expressions, classes, imports, container operations). - **C++ callable type support**: `callable[[Args],Ret]` → `std::function`. - **C++ range in arithmetic expansion**: `x in range(start, stop, step)` expanded to arithmetic check. - **C++ variant migration plan**: Replace `object` / box / unbox with `std::variant`. Verified basic operation, recursive types, RC sharing in `work/tmp/variant_test.cpp`. Phase 1 S1 complete. - **C++ selfhost S0-S4 complete**: All modules emit success, golden placed. S5 (build) onwards remaining. - **C++ lint all categories PASS**: P1-CPP-LINT-CLEANUP all 5 items resolved. Removed pytra.std. blanket skip from skip_modules. - **C++ g_type_table removed**: Switched to deleter pointer in ControlBlock. fixture 131/131 + sample 18/18 PASS. - **C++ integer literal redundant cast removal**: Added `literal_nowrap_ranges` table to CommonRenderer. Profile-driven bare literal / typed wrap switching. - **Rust in operator generalized**: Replaced per-arity PyContains with slice.contains(). - **EAST3 optimizer in-literal expansion**: Small literal `in` expanded to `||` chain. - **Rust inheritance ref consistency + super() resolution**: Base class ref promotion, super() type resolution in EAST2/EAST3. - **Rust fixture 132/132 + sample 18/18 PASS**: New emitter implementation, mapping.json, stdlib argparse parity PASS. - **Rust selfhost mod structure plan**: Designed migration from flat include! to Rust mod + use structure. - **Linker receiver_storage_hint**: Peer module class info attached to Attribute/Call nodes. - **pytra-cli.py C++/Rust emit subprocess delegation**: Selfhost no longer pulls in other language emitters. - **Parity changelog auto-recording**: PASS count changes auto-appended to progress-preview/changelog.md. Emitter lint changes also recorded. - **Emitter lint skip_pure_python category**: Detects pure Python modules in skip_modules. Added cli.py to exclusion list. - **New fixtures**: tuple_unpack_variants, typed_container_access, in_membership_iterable, callable_higher_order, object_container_access. - **spec-setup.md**: Consolidated clone setup instructions (golden + runtime east). - **spec-adt.md**: ADT specification — union type conversion per language (17 languages), recursive type handling, RC management rules, object fallback banned. - **Output path cleanup**: sample → sample-preview, progress → progress-preview, runtime east gitignored. - **Auto-generation intervals**: progress 3min, emitter lint 10min, selfhost 15min, benchmark 3min. - **TODO archive cleanup**: Merged date-split files (20260330-go.md, 20260330-p10reorg.md, 20260321b.md). - **P7-GO-SELFHOST-RUNTIME filed**: 3 gaps identified for Go selfhost binary. - **All-language selfhost TODO parity steps**: Added `run_selfhost_parity.py` fixture/sample parity to all language TODOs. - **Dockerfile: add TypeScript compiler**: `npm install -g typescript`. npm dependency eliminated (tsc + node). - **parity check: npx tsx → tsc + node**: Zero npm dependency. ## 2026-03-30 - **Go fixture all PASS**: Container types unified to reference wrappers. All 147 fixtures + stdlib 16/16 PASS. - **Rust emitter fixture 132/132 PASS**: arg_usage mut control, narrowing workaround. - **TypeScript emitter S5-S7 complete**: fixture 146/146, sample 18/18, JS 147/147 PASS. ESM migration, PNG encoder transpiled. - **C++ emitter P3-CR-CPP all complete**: S1-S8. isinstance unification, rc_from_value, keyword escaping. - **Fast parity check**: In-memory toolchain2 API calls. `--category` option. - **Automatic parity result accumulation + progress page**: 5 matrices (fixture/sample/stdlib/selfhost/emitter lint) + summary, auto-generated in ja+en. - **stdlib test separation**: Per-module tests in `test/stdlib/source/py//`. `--case-root stdlib` added. - **mapping.json types table**: Type mapping unified in mapping.json. `CodeEmitter.resolve_type()` API. - **Emitter hardcode lint**: 7-category grep-based violation detection. - **TODO per-area split**: cpp/go/rust/ts/cs/java/infra. P0 blocker rule removed. - **Golden files untracked**: ~400MB JSON removed from git. Regenerate with `regenerate_golden.py`. - **spec-runtime-decorator expansion**: extern_var, pipeline flow, quick reference table. - **Sample benchmark auto-measurement**: elapsed_sec recorded, sample README auto-updated. - **integer_promotion fixture**: All integer type widening/sign extension/mixed arithmetic tests. - **pytra.std.env added**: env.target compile-time constant via mapping.json. - **gc_reassign fixture fix**: __del__ body changed to pass (no GC-timing stdout). ## 2026-03-29 - **Go fixture all PASS**: Unified Go emitter container types to reference wrappers (`*PyList[T]`, `*PyDict[K,V]`, `*PySet[T]`) (P1-GO-CONTAINER-WRAPPER S1-S3). All 147 fixtures + stdlib 16/16 PASS. - **Rust emitter new implementation (P7-RS-EMITTER)**: New Rust emitter in `src/toolchain2/emit/rs/` with CommonRenderer + override architecture. mapping.json created. Fixture emit success. - **TypeScript emitter new implementation (P8-TS-EMITTER)**: New TS emitter in `src/toolchain2/emit/ts/`. JS covered by type annotation stripping flag on the same emitter. mapping.json created. 142 fixtures emit success. - **C++ emitter parity improvements (P3-CR-CPP)**: Reserved word escaping (`_safe_cpp_ident`), optional dict.get, float/container printing fixes. oop 18/18, typing 22/22, signature 13/13 PASS. - **C++ runtime exception safety (P3-CR-CPP-S4)**: Rewrote 5 `Object` constructors in py_types.h to use `make_unique` + `release` pattern. - **Fast parity check**: New `runtime_parity_check_fast.py` using in-memory toolchain2 API calls for transpile stage, eliminating subprocess startup and disk I/O. - **`--category` option for runtime_parity_check**: Run parity checks per fixture subdirectory (oop, control, typing, etc.) instead of all 146+ cases. - **Automatic parity result accumulation + progress page (P5-BACKEND-PROGRESS)**: Parity check auto-writes to `.parity-results/` with per-case merge and timestamps. `tools/gen/gen_backend_progress.py` generates fixture/sample/selfhost matrices in both Japanese and English. - **mapping.json validator (P10.5-MAPPING-VALIDATE)**: New `tools/check/check_mapping_json.py` validating required entries (`env.target`), format, and structure for all languages. Integrated into `run_local_ci.py`. - **spec-runtime-decorator expansion**: Added `extern_var` section, pipeline resolution flow (parser → resolve → emitter responsibilities), quick reference table. - **spec-emitter-guide expansion**: §1.4 generated code quality (exception safety, reserved word escaping, generic `rc_from_value`), §7.1-7.3 mapping.json constant substitution, literal embedding, mandatory `env.target`. - **spec-tools reorganization**: Split into index + 3 detail pages (daily, parity, update-rules). Removed 7 unregistered tools. - **TODO per-area split**: Reduced `todo/index.md` to index only, split into `cpp.md` / `go.md` / `rust.md` / `ts.md` / `infra.md`. Each agent reads/writes only its own area file. Removed P0 global blocker rule. - **Legacy `@abi` reference cleanup**: Removed `@abi` / `runtime_abi_v1` from spec-east, spec-dev, spec-runtime, guide, and tutorial. Unified to `@runtime` / `@extern`. - **PNG fixture path fix**: Changed output from `out/` to `test_png_out/` with `os.makedirs`. Fixes parity check cwd mismatch. ## 2026-03-28 - **Go exception handling completed (P0-EXCEPTION-GO)**: Typed catch, accurate catch/rethrow for custom exceptions, `raise ... from ...`, bare rethrow, and union-return vertical slice implemented. Builtin exceptions consolidated into `pytra.built_in.error`. - **C++ native exception lowering (P0-EXCEPTION-CPP)**: Native exception lowering implemented for the C++ backend. - **Go selfhost progress (P2-SELFHOST)**: Lowering profile support, reference wrapper default for container locals, `yields_dynamic`-based type assertion, Go mapping dispatch + parity coverage completed. P2-LOWERING-PROFILE-GO completed. - **CommonRenderer extensions**: elif chain rendering moved to common renderer. C++ common renderer parity regressions fixed. - **type_id table linker generation (P0-TYPE-ID-TABLE)**: Spec and implementation for linker-generated `pytra.built_in.type_id_table`. Hardcoded type_id deprecation policy finalized. - **@runtime / @extern decorator design completed (P0-RUNTIME-DECORATOR)**: Unified to `@runtime("namespace")` + `@extern` + `runtime_var("namespace")`. Auto-derivation rules, `symbol=` / `tag=` optional overrides, and include file structure specified in spec-runtime-decorator.md. Legacy `@extern_method` / `@abi` abolished. - **P0-CPP-INCLUDE-PATH-FIX**: Fixed runtime include path inconsistency in C++ emitter. - **P0-GO-PATHLIB-FIX**: Fixed Go emitter pathlib signature issues (joinpath vararg, read_text/write_text). - **Spec restructuring**: 12 legacy specs archived. spec-codex.md renamed to spec-agent.md. spec/index.md reorganized into categorized tables. 6 previously unlinked specs added. spec-opaque-type.md (`@extern class` type contract) created. - **Guide section added**: 5 guide pages (EAST, emitter, type system, runtime, extern/FFI) added to docs/guide/. Guide section positioned between Tutorial and Specification. - **Tutorial expansion**: Exception handling, Python differences, module reference (argparse/glob/re/enum/timeit), and samples pages added. Reading order restructured. - **AGENTS.md split**: Separated into planner / coder role-specific specs. Minimized bootstrap entry. ## 2026-03-27 - **C++ emitter spec compliance (S1-S15)**: Fail-fast, mapping.json unification, container reference wrappers (`Object>` etc.), implicit_promotions, is_entry/main_guard_body, @property support, shared runtime path resolution. - **Traits (pure interface, multiple implementation)**: `@trait` / `@implements` decorators for pure interfaces. C++ uses virtual inheritance + `Object` converting constructor; Go uses interface generation. Trait isinstance is compile-time only (no runtime info needed). - **isinstance narrowing**: Automatic type environment update after `if isinstance(x, T):` in the resolve stage. Supports if/elif, early return guard (`if not isinstance: return`), ternary isinstance (`y = x if isinstance(x, T) else None`), and `and`-chained conditions. - **Ternary Optional type inference**: `expr if cond else None` → `Optional[T]`, different types → `UnionType` inferred at resolve. - **pytra.std.json parser support**: PEP 695 recursive type alias (`type JsonVal = ...`) and Union forward reference now parseable. Golden files regenerated. - **POD isinstance**: `isinstance(x, int16)` etc. implemented as exact type match. Specified in spec-type_id.md §4.2. - **Link input completeness check**: Unresolved imports in link-input are reported as fail-closed errors. Type stubs for unparseable modules. - **ClosureDef lowering**: Nested FunctionDef lowered to ClosureDef in EAST3 with capture analysis (readonly/mutable). - **Lowering profile design**: Language capability declarations (tuple_unpack_style, container_covariance, with_style, etc. — 16 items) added to spec-language-profile.md §7. CommonRenderer design in §8. - **Tutorial additions**: Union types and isinstance narrowing, Traits tutorial pages added. English translations included. ## 2026-03-26 - **Pipeline redesign completed**: All 6 stages of the pipeline (`parse → resolve → compile → optimize → link → emit`) via `pytra-cli` are fully operational. toolchain2 is a completely independent implementation with no dependency on toolchain. - **Go backend migrated to new pipeline**: Go emitter + runtime implemented on the new pipeline. 18/18 samples emit success. Legacy Go emitter/runtime removed. - **C++ emitter new implementation**: New pipeline C++ emitter implemented in `toolchain2/emit/cpp/`. fixture 132/132, sample 18/18 emit success. - **CodeEmitter base class**: runtime_call mapping via `mapping.json` shared across all emitters. Hardcoding removed. - **Spec conformance (Codex-review)**: 20+ spec violations fixed across resolve/parser/validator/linker/emitter. - **spec-east1.md / spec-east2.md**: EAST1 (type-unresolved) and EAST2 (type-determined) output contracts formally defined. - **spec-builtin-functions.md**: Built-in function declaration spec. POD/Obj type classification, dunder delegation, extern_fn/extern_var/extern_class/extern_method. - **spec-runtime-mapping.md**: mapping.json format spec. implicit_promotions table. - **Integer promotion**: Numeric promotion casts conforming to C++ usual arithmetic conversion inserted at resolve. - **bytearray support**: `pytra/utils/png.py` / `gif.py` rewritten from `list[int]` to `bytearray`. Maps to `[]byte` in Go. ## 2026-03-25 - **All P0 tasks completed**: All stages (parse/resolve/compile/optimize/link/emit) match golden file tests. - **test/ directory reorganization**: Organized into 5 categories: fixture/sample/include/pytra/selfhost. - **Automatic golden file regeneration**: `tools/gen/regenerate_golden.py` for batch regeneration of all golden files. - **Go emitter**: Implemented as the reference emitter. fixture 132/132, sample 18/18 emit success. - **Go runtime + parity**: 18/18 samples pass `go run` + stdout match. Go is 63x faster than Python. - **Go runtime decomposition**: Split `pytra_runtime.go` monolith into `built_in/` + `std/` + `utils/`. ## 2026-03-24 - **Pipeline redesign started**: Designed 5-stage pipeline (parse/resolve/compile/optimize/emit), later expanded to 6 stages with link. - **toolchain2/ created**: New pipeline implementation independent of existing toolchain/. Selfhost-ready (no Any/object, pytra.std only). - **pytra-cli**: New CLI with -parse/-resolve/-compile/-optimize/-link/-emit/-build subcommands. - **EAST1 golden files**: Golden files stripped (type info removed) conforming to spec-east1. 150 files. - **Built-in function declarations**: `src/include/py/pytra/built_in/builtins.py` + `containers.py`. v2 extern (extern_fn/extern_var/extern_class/extern_method). - **stdlib declarations**: v2 extern declarations for math/time/glob/os/sys etc. in `src/include/py/pytra/std/`. ## 2026-03-23 - Dart emitter dead code removal (14 functions deleted). Runtime helper dedup. 18/18 parity. - Nim emitter spec-emitter-guide compliance improvements. Introduced `build_import_alias_map`, `yields_dynamic` support. - Common test suite for all backends. `runtime_parity_check.py` enables fixture 131 execution across all languages. - EAST3 type inference bug fixes x4 (reported by Nim: Swap, returns, VarDecl, list[unknown]). - ContainerValueLocalHintPass generalized to all backends. - Swap node constrained to Name-only, Subscript swap expanded to Assign. - `unused: true` added to `_` elements in tuple destructuring. - cast() resolved_type fix + list.pop() generic resolution. - C++ multi-file emit runtime east path resolution fix. - C++ test_py2cpp_features.py pass rate 64% → 95%. ## 2026-03-22 - REPO_ROOT fix + import alias resolution + conftest extern function fix. - `build_multi_cpp.py` generated source changed to include-tracking-based auto-linking. - Object migration phases 1–4 completed (ControlBlock, emitter, list/dict, legacy type removal). ## 2026-03-21 - Removed `noncpp_runtime_call` / `noncpp_module_id` from EAST1 parser (resolving EAST1 responsibility violation). - Decomposed py_runtime.h into 6 files with facade pattern. - Runtime .east auto-integrated into link pipeline. - Unified object = tagged value. Tagged union unified to PyTaggedValue (object+tag). - Removed all legacy object APIs (make_object, obj_to_rc_or_raise, etc.). - Escape analysis results reflected in class_storage_hint. Union type parameters forced to ref (gc_managed). - Self-contained C++ output: auto-generated declaration headers for extern modules. ## 2026-03-20 | v0.15.0 - PowerShell backend added. Generates native PowerShell code directly. - Zig backend: pathlib native implementation + generic native re-export mechanism → 18/18 parity achieved. - Go/Lua fixture parity improvements (wave 2). - Ruby emitter: fixture parity improvements (Is/IsNot, lambda, str iteration, dunder methods, runtime extensions). - C# emitter: @extern delegation code generation + build pipeline fixes. ## 2026-03-18 | v0.14.0 - Recursive union types (tagged unions) supported. spec-tagged-union.md established. - Nominal ADT: parser → EAST3 lowering → C++ backend implemented end-to-end. - Match/case exhaustiveness check (closed nominal ADT family). - Non-C++ backends fail-closed on nominal ADT lane. ## 2026-03-14–17 - EAST core module decomposition (core.py 8000 lines → 20+ files). - IR core decomposition: builder, expr, stmt, call metadata, type parser etc. into individual modules. - Backend registry selfhost parity strengthening. Local CI reentry guard. ## 2026-03-11–13 | v0.13.0 - Built an NES (Famicom) emulator in Python + SDL3. Improving Pytra to enable C++ transpilation. - Linker spec established (spec-linker.md). Compile / link pipeline plan. - Common smoke test infrastructure for all backends. `test_py2x_smoke_common.py` as source of truth. - Non-C++ backend health gate aggregated by family. ## 2026-03-10 | v0.12.0 - Major runtime reorganization. C++ generated runtime header generation pipeline established. - `src/runtime/cpp/{generated,native}` responsibility separation established. - Runtime .east files as source of truth, with automatic C++ header generation. ## 2026-03-09 | v0.11.0 - Object boundary redesign. Selfhost stage2 parity (pass=18 fail=0) achieved. - Tutorial setup (tutorial/README.md, how-to-use.md). ## 2026-03-08 | v0.10.0 - `@template` now usable. v1 for linked runtime helpers. - Runtime for each language under development. Debian 12 parity bootstrap. - Completion criteria defined for all-target sample parity. ## 2026-03-07 | v0.9.0 - Major refactoring completed. All languages usable again. - `@extern` and `@abi` now usable, enabling transpiled code to be called from other languages. - Selfhost stage1 build + direct .py route green. ## 2026-03-06 | v0.8.0 - ABI boundary redefined, major refactoring in progress. - spec-abi.md established (@extern / @abi fixed ABI types). - Non-C++ transpilers temporarily broken. ## 2026-03-04 | v0.7.0 - PHP added as a transpilation target. Nim formal support in progress. ## 2026-03-02 | v0.6.0 - Scala added as a transpilation target. ## 2026-03-01 | v0.5.0 - Lua added as a transpilation target. ## 2026-02-28 | v0.4.0 - Ruby added as a transpilation target. ## 2026-02-27 | v0.3.0 - EAST (intermediate representation) reorganized into staged processing (EAST1 → EAST2 → EAST3). - Major decomposition / reduction of C++ CodeEmitter. ## 2026-02-25 | v0.2.0 - All languages (C++, Rust, C#, JS, TS, Go, Java, Kotlin, Swift) now output code closely resembling the original source. ## 2026-02-23 | v0.1.0 - Pytra initial release. Generates highly readable C++ code that closely mirrors the original Python source style.