# Changelog

All notable changes to cargoxx will be documented in this file.

## [Unreleased]

### Added
- M0 repo skeleton: hand-written `CMakeLists.txt`, bootstrap `flake.nix`,
  empty C++23 module units for every component listed in `TECH_SPEC.md` §1
  (`util`, `exec`, `manifest`, `lockfile`, `layout`, `linkdb`, `resolver`,
  `codegen`, `cli`), root module `cargoxx`, and a stub `main.cpp` that
  builds an empty `cargoxx` binary.
- `.clang-format` (LLVM, 100-column) and `.gitignore`.
- `SPEC.md`, `TECH_SPEC.md`.
- M1 foundation in `cargoxx.util`: `ErrorCode` (numbers per `TECH_SPEC.md` §4),
  `Error`, `Result<T> = std::expected<T, Error>`, and `format(Error)` rendering
  `error[Ennnn]: ...` with optional `--> path:line:col` and `hint:` lines.
  `format` lives in `src/util/error.cpp` as a module implementation unit.
- `Catch2 v3` wired through `flake.nix` (libc++-built override) and registered
  in CMake; `tests/util_error.cpp` covers six format cases via
  `catch_discover_tests`.
- `cargoxx.manifest` public types (`Package`, `Dependency`, `BuildSettings`,
  `Edition`, `Manifest`) and `parse(path)` returning `Result<Manifest>`,
  backed by toml++ vendored as `third_party/toml.hpp`. Unknown keys in
  `[package]` / `[build]` and unknown top-level keys are rejected; reserved
  fields (`description`, `repository`, `[dev-dependencies]`, `[features]`,
  `[workspace]`) are accepted. `tests/manifest_parse.cpp` covers 17 cases.
- `manifest::write(m, path)` serializes a `Manifest` as TOML using toml++.
  Dependencies are emitted alphabetically (matches Cargo). Round-trip
  property is exercised by `tests/manifest_write.cpp` (9 cases).
  Defaulted `operator==` on the manifest structs supports comparison.
- `cargoxx.layout` public types (`Target`, `TargetKind`, `DiscoveredLayout`)
  and `discover(project_root, package_name)`. Walks `src/` recursively
  for the library (excluding the `src/bin/` subtree), enumerates
  `src/main.cpp`, `src/bin/*.cpp`, `tests/*.cpp`, `examples/*.cpp` flat,
  sorts results for deterministic output, and returns `LayoutNoTarget`
  when neither a library nor any binary is present.
  `tests/layout_discovery.cpp` covers 12 cases.
- `cargoxx new <name>` and `cargoxx new --lib <name>` scaffold a project
  directory with `Cargoxx.toml`, `src/main.cpp` or `src/lib.cppm`, and a
  minimal `.gitignore`. Hyphens in the package name are mapped to
  underscores when generating the module/namespace identifier.
  Codegen of `flake.nix` / `CMakeLists.txt` is intentionally deferred to M3.
  CLI11 v2.6.2 vendored at `third_party/CLI11.hpp`; entry point is now
  `cargoxx::cli::run(argc, argv)`. `tests/cmd_new.cpp` covers 9 cases.
- `util::satisfies(version, range)` — minimal semver range matcher
  supporting `*`, `==/>=/<=/>/<` operators, and comma-separated AND
  clauses. Versions are zero-padded to three components.
  `tests/semver_satisfies.cpp` covers 7 cases.
- `cargoxx.linkdb`: `Recipe`, `Database::open()`, `Database::resolve(...)`
  for curated lookups. The curated database ships at `data/linkdb.json`
  with all 25 packages from `SPEC.md` §11. Component-substitution helpers
  expand `{{components}}` (space-joined) in `find_package` and fan out
  `{{component}}` per-target. Path is injected via the
  `CARGOXX_LINKDB_DEFAULT_PATH` compile definition. nlohmann/json 3.12.0
  vendored at `third_party/json.hpp`. SQLite overlay and `add_manual`
  are deferred to the M2 follow-up commit.
  `tests/linkdb_lookup.cpp` covers 13 cases including a smoke test that
  resolves all 25 curated packages.
- `cargoxx.lockfile`: `Lockfile`, `LockfilePackage` types and `parse(path)` /
  `write(lock, path)` matching the format in `SPEC.md` §5. Also
  `Lockfile::nixpkgs_rev()` returns the shared revision (codegen will
  consume this in M3). `tests/lockfile_round_trip.cpp` covers 9 cases.
- `cargoxx.codegen`: `GenerateInputs` plus the pure function
  `flake_nix(in) -> std::string`. Substitutes the package name, the
  resolved nixpkgs revision (defaulting to `nixos-unstable` when the
  lockfile pins none), and a deduplicated list of dep `nixpkgs_attr`
  entries into `buildInputs`. Output is byte-deterministic.
  `tests/codegen_flake.cpp` covers 7 cases. Note: SPEC §7's template did
  not show `buildInputs`; we add one between `nativeBuildInputs` and the
  `env.NIX_CFLAGS_COMPILE` block as the natural slot for the deps that
  TECH_SPEC §10 says we splice in.
- `codegen::cmake_lists(in) -> std::string` per `SPEC.md` §8 and
  `TECH_SPEC.md` §9: `find_package` per dep, optional library target
  with module units + private impl sources, primary binary
  `<pkg>_bin` linked against the library, additional binaries from
  `src/bin/`, tests with `enable_testing()` + `add_test`, examples,
  and `[build]` honoring `warnings_as_errors` and `sanitizers`. Source
  paths emitted relative to `build/` (i.e. prefixed with `../`).
  Output is deterministic. `tests/codegen_cmake.cpp` covers 11 cases.
- `cargoxx.linkdb::Database::insert_provisional`,
  `confirm_provisional`, and `abort_provisional` — three-step lifecycle
  for non-`manual` overlay rows: insert with `verified_at = 0`, run a
  build, then either bump `verified_at = now` on success or `DELETE`
  the row on failure.
- `cargoxx.resolver::verify_link(req, build_fn)` — scaffolds a tiny
  `Cargoxx.toml` + `int main() {}` project under a scratch dir, writes
  a provisional overlay row pointing at the candidate `Recipe`, runs
  the caller-supplied `BuildFn` (typically `cli::cmd_build` injected
  to avoid a resolver-on-cli dep cycle), and on success/failure
  confirms or aborts the provisional row. Cleans the scratch project
  via RAII regardless of outcome. `tests/verify_link_unit.cpp` exercises
  both success and failure paths against a mock `BuildFn`, verifying
  that the overlay row's lifecycle matches the build outcome.
- `cargoxx.resolver::vcpkg_probe(name)` — fetches
  `https://raw.githubusercontent.com/microsoft/vcpkg/master/ports/<name>/usage`
  and feeds it through `parse_vcpkg_usage`. The pure parser extracts
  the first `find_package(...)` arg block, adds `REQUIRED` if absent,
  and gathers `target_link_libraries` targets that contain `::` (skips
  generator expressions and bare names). `tests/vcpkg_probe_parse.cpp`
  covers 6 cases; `tests/vcpkg_probe_live.cpp` (gated by
  `CARGOXX_NETWORK_TESTS=1`) verifies fmt + a 404 path against real
  microsoft/vcpkg ports.
- `cargoxx.resolver::conan_probe(name)` — fetches
  `https://raw.githubusercontent.com/conan-io/conan-center-index/master/recipes/<name>/all/conanfile.py`
  via `curl` (text-only — never executes Python, per `SPEC.md` §14)
  and feeds it through `parse_conanfile`. Pure parser handles both the
  modern `set_property("cmake_target_name", "...")` form and the legacy
  `names["cmake_find_package"] = "..."` form, derives the missing field
  from the other when only one is set, normalizes bare names into the
  canonical `<file>::<target>` shape, and substitutes Python f-string
  `{...}` placeholders with the cmake_file_name so recipes like fmt's
  `f"fmt::{target}"` parse correctly. `tests/conan_probe_parse.cpp`
  covers 6 cases; `tests/conan_probe_live.cpp` (gated by
  `CARGOXX_NETWORK_TESTS=1`) verifies fmt and a 404 path against the
  real conan-center-index.
- `cargoxx.resolver::nix_cmake_scan(store_path, package_name)` — walks
  `<store_path>/lib/cmake/**` for `*Config.cmake` / `*-config.cmake`
  files, scans them and their sibling `.cmake` files (e.g. the
  `<pkg>-targets.cmake` that real packages like fmt put their
  `add_library(... IMPORTED)` calls in) for IMPORTED + ALIAS targets,
  and returns the `NixCmakeCandidate` whose derived stem best matches
  `package_name` (case-insensitive equality > prefix > first non-empty).
  Pure helpers `scan_imported_targets(text)` and
  `config_stem_to_package(filename)` are exported for unit testing.
  `tests/nix_cmake_scan_parse.cpp` covers 11 cases including a fixture
  that mirrors fmt's `<pkg>-config.cmake → <pkg>-targets.cmake`
  layout. `tests/nix_cmake_scan_live.cpp` (gated by
  `CARGOXX_NETWORK_TESTS=1`) realizes `nixpkgs#fmt.dev` via
  `nix build` and verifies `fmt::fmt` is discovered end-to-end.
- `cargoxx.resolver::nixpkgs_probe(attr)` — runs
  `nix eval nixpkgs#<attr> --json --apply 'p: { version, path }'` via
  `exec::run` and returns a `NixpkgsInfo { attr, version, out_path }`.
  Distinguishes missing attributes (`ResolutionUnknownPackage`) from
  evaluator/network errors (`ResolutionNetworkError`). The `path` field
  name avoids nix's `outPath`-driven derivation coercion in `--json`
  mode (which would otherwise serialize the result as a bare path
  string instead of a JSON object). Pure parser
  `parse_nix_eval_json(attr, text)` exposed for unit tests; live tests
  in `tests/nixpkgs_probe_live.cpp` are gated behind
  `CARGOXX_NETWORK_TESTS=1` (verified locally against `hello`).
- `cargoxx add <pkg>[@<version>] [--components a,b]` edits `Cargoxx.toml`,
  validates the new dep against the curated linkdb (so unknown packages
  and missing components fail before any disk write), and rejects
  already-declared deps. Version is now optional; an omitted version
  is stored as `"*"` and resolves against the linkdb's first matching
  recipe. Generated `flake.nix` continues to track the `nixos-unstable`
  branch when the lockfile carries no rev.
- `util::satisfies` treats `version == "*"` as a match against any
  range, mirroring the existing `range == "*"` shortcut.
- `scripts/verify-curated-db.sh` plus per-package using-snippets at
  `scripts/curated-snippets/<pkg>.cpp`. For each curated package the
  script scaffolds a fresh project, `cargoxx add`s the dep, drops in a
  snippet that exercises the library's API, and runs `cargoxx build`,
  asserting the binary is produced. 21/25 packages pass against
  `nixos-unstable`; the remaining 4 are documented as skipped:
  `catch2`/`gtest` (their default linkdb targets ship their own
  `main()` which collides with the snippet), `grpc` (needs `protobuf`
  declared as a transitive dep — cross-package transitives are out of
  v0.1 scope), `abseil-cpp` (nixpkgs builds it against libstdc++ while
  our flake uses libc++ → ABI mismatch on the linker step).
- `data/linkdb.json`: `boost` recipe is now header-only —
  `find_package(Boost REQUIRED)` + `Boost::headers`. Boost 1.89's
  `BoostConfig.cmake` searches for separately-installed
  `boost_<comp>Config.cmake` files that nixpkgs doesn't ship, so
  the previous `COMPONENTS` form failed at configure time.
  Linkdb-component tests now use `abseil-cpp` for component coverage.
- `cargoxx remove <pkg>` drops a declared dep from `Cargoxx.toml`,
  errors when the dep is not declared. Other deps are preserved.
- End-to-end verified on a freshly-scaffolded project. `tests/cmd_add.cpp`
  and `tests/cmd_remove.cpp` cover 9 cases. Known cosmetic issue:
  toml++ writes top-level sections alphabetically, so `[package]` may
  end up after `[dependencies]` post-mutation; logged for M6 polish.
- `cargoxx run [--release] [--bin <name>] [-- <args>...]`,
  `cargoxx test [--release]`, and `cargoxx clean`. `run` builds first,
  picks the binary (errors with the available list when the project
  has multiple bins and `--bin` is omitted), and execs it with the
  process exit code propagated. `test` invokes
  `nix develop -c ctest --test-dir build/<profile> --output-on-failure`.
  `clean` removes `build/` while leaving `Cargoxx.lock` and `flake.lock`
  intact. End-to-end verified against a freshly-scaffolded project.
  `tests/cmd_run.cpp` and `tests/cmd_clean.cpp` cover 6 cases.
- `cargoxx build` (without `--no-build`) now drives the full build:
  `nix develop -c cmake -B build/<profile> -S build -G Ninja
  -DCMAKE_BUILD_TYPE=<Profile>` then `nix develop -c cmake --build`
  with optional `--target`, both with `inherit_stdio = true` so the
  user sees compilation output live. Non-zero cmake exit returns
  `BuildCmakeFailed`. End-to-end verified: `cargoxx new myapp &&
  cargoxx build` produces a working `build/debug/myapp` that prints
  `Hello from myapp!`.
- Generated `build/CMakeLists.txt` now opts into the experimental
  `import std;` UUID + `CMAKE_CXX_MODULE_STD ON`, and sets
  `CMAKE_CXX_EXTENSIONS ON` (deviation from SPEC §8 — required for
  libc++'s std module to load without `module-file-config-mismatch`
  on clang 21). Without these the templates from `cargoxx new` fail
  to compile.
- `cargoxx.exec`: `ExecResult`, `ExecOptions`, and
  `run(program, args, opts)` — argv-only subprocess wrapper around
  reproc 14.2.4. Captures stdout/stderr (or inherits stdio when
  `opts.inherit_stdio` is set), supports `cwd`, `env_overrides`, and a
  `timeout` (enforced via `reproc_options.deadline` so drains return
  `REPROC_ETIMEDOUT` instead of blocking on long-lived streams). On
  destruction reproc terminates and then kills any still-running child.
  Returns `ExecToolNotFound` for `ENOENT` and `ExecCommandFailed` for
  other failures including timeouts. `tests/exec_run.cpp` covers 9 cases.
- `cargoxx build --no-build` end-to-end. Reads `Cargoxx.toml`,
  discovers the layout, opens the curated linkdb, resolves a `Recipe`
  per manifest dep, synthesizes a fresh `Cargoxx.lock`, and writes
  `flake.nix`, `build/CMakeLists.txt`, and `Cargoxx.lock`. With no
  resolver yet (M5), `nixpkgs_rev` is left null and the generated flake
  falls back to the `nixos-unstable` branch. Without `--no-build`, the
  command still generates files but returns a `NotImplemented` error
  pointing at M4. `tests/cmd_build.cpp` covers 8 cases.
- SQLite overlay: `Database::open(overlay_path)` now opens (and creates,
  if missing) a per-user `linkdb.sqlite` cache, applying the schema from
  `SPEC.md` §9 idempotently. Default path is
  `$XDG_CACHE_HOME/cargoxx/linkdb.sqlite` (falling back to
  `$HOME/.cache/cargoxx/...`); tests pass an explicit temp path so they
  never touch the user cache. `Database::add_manual(pkg, range, recipe)`
  inserts a row with `source = 'manual'` and `verified_at = now()`;
  `resolve()` consults the overlay first and falls back to curated when
  no overlay row matches the requested version range. Manual entries
  never expire; `nix-probe` (v0.2) entries respect a 30-day freshness
  window. `tests/linkdb_overlay.cpp` covers 7 cases (insert/persist,
  override-curated, version-range gating, components rejection,
  move semantics).