validate.yml

name: validate

on:
  pull_request:
    # mcpp.toml and index.toml carry the workspace member list, the inherited
    # [indices] redirect and the client version floor — a change to any of them
    # can break every member, so they gate the run like the descriptors do.
    paths: ["pkgs/**/*.lua", "tests/**", "README.md", "README.zh-CN.md", "mcpp.toml", "index.toml", ".github/workflows/validate.yml"]
  push:
    branches: [main]
  schedule:
    # nightly full regression — exercises every workspace member regardless of diff
    - cron: "0 6 * * *"
  workflow_dispatch:
    inputs:
      cache:
        description: "Package build cache — 'local' rebuilds every dependency per member, which is what the timing table should be read against when comparing"
        type: choice
        options: [global, local]
        default: global

env:
  # 2026.8.5.4 carries two things this workflow depends on:
  #   .5.1  `tools = [...]` — how a consumer asks for a dependency's
  #         `kind = "bin"` target, which tests/examples/protobuf-protoc is built
  #         on. Before it: "tools must be a string, inline dep table, or nested
  #         table".
  #   .5.4  windows links with lld. link.exe caps a response-file LINE at
  #         128 KiB and opencv-module / opencv-module-dnn went past it —
  #             fatal error LNK1170: line in command file contains 135135 or
  #             more characters
  #         after 795s / 1166s of compiling. .5.3 newline-separated OUR response
  #         file, which was necessary but not sufficient: clang, acting as the
  #         driver, writes a SECOND one for the linker that we do not control.
  #         lld's response-file parser has no per-line limit at all.
  #         Together with re-enabling the global package cache below, this is
  #         what makes a green FULL run possible again: .5.3 removes the
  #         windows link failure, the cache removes the 150-minute timeout.
  #
  # Neither of them moves index.toml's min_mcpp: exposing compat.protobuf's `protoc`
  # target is additive, and 2026.8.3.3 still parses that descriptor with an
  # empty unknown_keys. The floor an index publishes decides whether older
  # clients keep working at all (mcpp#349), so it moves only when a descriptor
  # genuinely stops being readable — which is not the case here.
  # 2026.8.3.1: on macOS, a global object that touches std::cout during static
  # init crashes on sight (mcpp#336). Mach-O has no priority-ordered init
  # section and libc++'s <iostream> carries no ios_base::Init guard of its own,
  # so the streams are still all-zero when an archive member's initializer
  # runs. mcpp now links a generated object FIRST whose constructor brings them
  # up. It is not fixable package-side — std::ios_base::Init is only
  # forward-declared in libc++'s <ios> — so boost-ext.ut genuinely requires
  # this floor on macOS, and min_mcpp/latest_mcpp move with the pin as they
  # always have (a consumer below the floor would get a segfault with no
  # diagnostic, which is worse than E0006).
  # 2026.8.3.3 is the pin rather than .3.1: .3.2/.3.3 are cross-compilation
  # fixes (PE artifact naming, -static host-vs-target) that no leg of this
  # matrix exercises, so taking the newest of the train costs nothing.
  # 0.0.109: a bare dependency's wire address takes BOTH halves from the
  # descriptor the identity gate accepted (mcpp#286). This is the client-side
  # other half of the SPEC-001 migration below: mcpp used to take the NAME from
  # the descriptor and the NAMESPACE from the request, so a bare `gtest =
  # "1.15.2"` addressed `mcpplibs:gtest` — a key no index has. It only ever
  # worked because the pre-migration literal `package.name` read
  # "compat.gtest", which the hardcoded `compat.<short>` retry then caught.
  # Short names removed that coincidence and left every bare request against
  # this index broken on 0.0.108, which is why min_mcpp moves to 0.0.109.
  # Note this index cannot cover that spelling itself: the `[indices]` redirect
  # is keyed by the REQUEST's namespace, so a bare dependency resolves from the
  # published remote index rather than the checkout under test. Bare-name
  # resolution against a short-name index is upstream's e2e 165; what moving
  # the floor buys here is that consumers of THIS index get a client that can
  # address it.
  # 0.0.106: SPEC-001 package identity (mcpp#280). `package.name` is a SINGLE
  # ATOMIC SEGMENT — all hierarchy lives in `package.namespace` — and mcpp
  # addresses a package by the LITERAL name it read, so descriptors no longer
  # repeat their namespace inside `name`. This index is migrated to the short
  # form, which is why min_mcpp/latest_mcpp move in lock-step: an older client
  # re-derives `<ns>.<short>`, misses, and reports a bare E_NOT_FOUND. Bundles
  # xlings 0.4.69, which keys its index by (namespace, name) so two packages
  # sharing a short name in one index are both addressable (xlings#381) — this
  # index now has three such pairs (imgui / ffmpeg / lua under compat vs the
  # default namespace).
  # 0.0.102: windows command-line ceiling (mcpp#261 — the clang scan rule got
  # its P1689 JSON through shell redirection, which forced a `cmd /c` wrapper
  # and with it cmd.exe's 8191-char limit; clang-scan-deps -o removes both, and
  # $local_includes-carrying rules now fall back to response files). The pin
  # matters here because a package consumed FROM the registry sits under a
  # ~124-char xpkgs path instead of its own ~23-char checkout, which is what
  # pushed the vendored-opencv scan command over the line. Also: purview-include
  # depfile tracking extended to Clang (#257 — stale BMI reuse), OS-conditional
  # `[build].flags` (#258), and per-OS splices keyed on the resolved target
  # rather than the host (#254).
  # 0.0.101: per-feature per-glob flags + per-OS features (mcpp#253) — what
  # lets opencv select its dnn gemm backend per platform.
  # 0.0.99: feature dep/feat forwarding (mcpp#243 — a feature can open a
  # feature OF a dependency, e.g. opencv `dnn` forwarding compat.opencv/dnn);
  # vendored xlings 0.4.67 for the >=2 index_repo install fix (mcpp#238 /
  # openxlings/xlings#374); build.mcpp compiled program named `.exe` on
  # Windows (mcpp#230 secondary surface, after the 0.0.96 scanner crash fix).
  # 0.0.98: closes the obj-path disambiguation follow-ups that gated the
  # source-build compat.opencv unification — #240 (link inputs now follow
  # the disambiguated object names, so a dependency + consumer sharing a
  # source basename like `src/main.cpp` no longer 'obj/main.o missing') and
  # #239 (absolute/`..` dep-generated source paths sanitized component-wise
  # so objects stay under obj/). Also: `MCPP_DEP_<NAME>_DIR` build.mcpp
  # contract (#241), consumer-side `default-features = false` (#242), and a
  # loud unknown-mcpp-key warning with did-you-mean (#237, replaces the
  # silent-ignore at build time). Carried from 0.0.97: default-namespace
  # index redirect (`[indices] default = { path }`), which turned the public
  # module packages (imgui/ffmpeg/opencv/tinyhttps) into ordinary workspace
  # members and retired the per-package reseeding smoke shells + their
  # dedicated jobs; synchronous nasm bootstrap (mcpp#232 — the `mcpp index
  # update` pre-step is gone), obj-path disambiguation (#233), spacey-defines
  # quoting (#234), purview-include depfile tracking (#235). Older floors of
  # note: 0.0.96 fixed the windows scanner symlink-escape crash (mcpp#230);
  # 0.0.94 fixed feature-gated `sources` under `mcpp test` (mcpp#218); 0.0.91
  # added standard = "c++fly" to the resolver grammar, so c++fly descriptors
  # get the lint WARN below, not a hard grammar-parse rejection.
  # 2026.8.6.1 是本次身份迁移的**前置**,不是顺手升级。
  #
  # `Fetcher::install_path(ns, shortName, version)` 的 legacy 扫描此前匹配任何以
  # `-x-<shortName>` 结尾的目录、不看命名空间,于是查 `ocornut:imgui@1.92.8` 会拿到
  # `compat-x-imgui/1.92.8` —— 另一个仅仅短名相同的包。它一直够不到,是因为 module
  # 层用打包计数(imgui@0.0.6)而 compat 用上游版本(compat.imgui@1.92.8),版本永远
  # 不撞;本次把 module 层对齐到上游之后它们重合了。mcpp#364 修掉了它。
  #
  # index.toml 的 min_mcpp **不动**。两个会撞的 compat 邻居都是 Form B,所以旧客户端
  # 撞上时是响亮报错而不是静默用错包;下限是一道让整个索引对旧客户端失效的闸门
  # (mcpp#349),只该在描述符真的读不动时抬。这里读得动,差的是解析得对。
  MCPP_VERSION: "2026.8.6.2"

jobs:
  lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: Install lua
        run: sudo apt-get install -y --no-install-recommends lua5.4
      - name: Lint package descriptors
        run: |
          fail=0
          for f in pkgs/*/*.lua; do
            # 1. Lua syntax check — load (= compile) without executing.
            #    `loadfile(name, 't')` rejects bytecode and parses text only.
            if ! lua5.4 -e "assert(loadfile('$f', 't'))" >/dev/null 2>&1; then
              echo "::error file=$f::lua syntax error"
              fail=1
            fi
            # 2. xpkg V1 baseline: the file has to populate `package = { ... }`
            #    with at least `spec`, `name`, and an `xpm` table. Form A vs
            #    Form B (mcpp = "<path>" / mcpp = { ... }) is descriptor-author
            #    choice and not enforced here.
            for needle in 'spec *=' 'name *=' 'xpm *='; do
              if ! grep -q "$needle" "$f"; then
                echo "::error file=$f::missing required field ($needle)"
                fail=1
              fi
            done
            # 3. Package version identifiers and dependency versions should be
            #    bare versions ("1.2.3"), not upstream tag names ("v1.2.3").
            #    Download URLs may still contain refs/tags/v* when upstream
            #    uses that tag spelling.
            if grep -nE '\["v[0-9]+|\["[^"]+"\][[:space:]]*=[[:space:]]*"v[0-9]+' "$f"; then
              echo "::error file=$f::version identifiers must not use a leading v"
              fail=1
            fi
            # 4. Mirror table sanity: when a download `url` is written as a
            #    { GLOBAL=..., CN=... } table, both regions must be present and
            #    the CN entry must point at the gitcode mcpp-res mirror.
            if ! lua5.4 tests/check_mirror_urls.lua "$f"; then
              fail=1
            fi
            # 5. `name` must be a SINGLE ATOMIC SEGMENT; hierarchy belongs in
            #    `namespace` (mcpp SPEC-001 §3.2). The legacy fully-qualified
            #    spelling stays accepted. Cheap second gate: it runs before the
            #    pinned mcpp is even downloaded, and mcpp >= 0.0.106 enforces
            #    the same rule inside `mcpp xpkg parse`.
            if ! lua5.4 tests/check_package_name.lua "$f"; then
              fail=1
            fi
            # 6. c++fly admission policy (mcpp design 2026-07-14 §11-Q2, v1):
            #    c++fly means "toolchain's latest level + every experimental
            #    gate" — deliberately toolchain-dependent, so a published
            #    package built with it is not reproducible for consumers.
            #    Policy: WARN (never fail) and observe ecosystem usage before
            #    deciding whether to tighten. Two spellings: `language = ` is
            #    the descriptor's inline mcpp-segment key; `standard = ` covers
            #    mcpp.toml content embedded in heredoc/generated_files blocks.
            if grep -nE '\b(language|standard)[[:space:]]*=[[:space:]]*"c\+\+fly"' "$f" >/dev/null; then
              echo "::warning file=$f::declares C++ standard \"c++fly\" (experimental playground mode) — toolchain-dependent and non-reproducible for consumers; published packages should pin a concrete standard (c++23/c++26)"
            fi
          done
          [ $fail -eq 0 ] && echo "All package files valid."
          exit $fail
      # ── Whole-repository check (needs every descriptor at once) ──────
      # An install() hook addressing a sibling package does so by
      # `<namespace>:<literal package.name>`, and a miss returns nil rather
      # than raising — so a stale spelling surfaces far downstream (a broken
      # libxcb showed up as a libX11 link error). Verified across the repo
      # because it needs the full set of declared identities.
      - name: Lint cross-package references
        run: lua5.4 tests/check_cross_package_refs.lua pkgs/*/*.lua
      # ── Partial version bumps ────────────────────────────────────────
      # A bump is a one-line-looking edit that has to land in N platform
      # sections. Editing `xpm.linux` and reading the file back gives a file
      # that CONTAINS the new version, so the author -- and any whole-file
      # grep -- sees success, while the other platforms are left behind. The
      # failure then surfaces as `<pkg>@<ver> not found` on a platform,
      # against a file that literally contains that version string.
      #
      # Measured 2026-08-06: xpkg 0.0.52 and 0.0.53 were both added to
      # `xpm.linux` alone; linux CI went green twice while macOS and Windows
      # failed, and eight checks made from the outside all came back correct
      # because each asked "is it in the index?" instead of "is it in THIS
      # platform's section?". Whole-repo, because a partial bump is only
      # visible by comparing sections against each other.
      - name: Lint platform version parity
        run: lua5.4 tests/check_platform_version_parity.lua pkgs/*/*.lua
      # ── Single-source-of-truth grammar check ─────────────────────────
      # `mcpp xpkg parse` uses EXACTLY the resolver's parser, so what
      # passes here is what builds for users of the pinned MCPP_VERSION.
      # Strict by default: unknown mcpp-segment keys fail (they would be
      # silently ignored at build time). This also mechanically enforces
      # the rollout rule "floor first, new grammar after": descriptors
      # needing a newer grammar cannot pass a lint pinned to an older mcpp.
      - name: Download pinned mcpp
        run: |
          curl -L -fsS -o mcpp.tar.gz \
            "https://github.com/mcpp-community/mcpp/releases/download/v${MCPP_VERSION}/mcpp-${MCPP_VERSION}-linux-x86_64.tar.gz"
          tar -xzf mcpp.tar.gz
          echo "MCPP=$PWD/mcpp-${MCPP_VERSION}-linux-x86_64/bin/mcpp" >> "$GITHUB_ENV"
      - name: Parse descriptors with the resolver grammar (mcpp xpkg parse)
        run: |
          fail=0
          for f in pkgs/*/*.lua; do
            if ! "$MCPP" xpkg parse "$f" > /dev/null; then
              echo "::error file=$f::mcpp xpkg parse failed (resolver grammar)"
              fail=1
            fi
          done
          [ $fail -eq 0 ] && echo "All descriptors parse with mcpp ${MCPP_VERSION}."
          exit $fail

  mirror-cn-reachable:
    # Closed-loop guard for the CN mirror: every CN url referenced by a
    # descriptor must be a live, downloadable gitcode release asset.
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: Install lua
        run: sudo apt-get install -y --no-install-recommends lua5.4
      - name: Check CN mirror assets are reachable
        run: |
          fail=0
          # collect unique CN urls across all descriptors
          : > /tmp/cn.tsv
          for f in pkgs/*/*.lua; do
            lua5.4 tests/list_cn_urls.lua "$f" >> /tmp/cn.tsv || true
          done
          sort -u /tmp/cn.tsv -o /tmp/cn.tsv
          total=$(grep -c . /tmp/cn.tsv || true)
          echo "checking $total CN mirror url(s)"
          while IFS=$'\t' read -r url sha; do
            [ -z "$url" ] && continue
            # follow redirects; gitcode release assets resolve to object storage
            code=$(curl -fsSL -o /dev/null -w '%{http_code}' --retry 2 --max-time 60 "$url" || echo "000")
            if [ "$code" != "200" ]; then
              echo "::error::CN mirror unreachable ($code): $url"
              fail=1
            else
              echo "ok: $url"
            fi
          done < /tmp/cn.tsv
          [ $fail -eq 0 ] && echo "All CN mirror urls reachable."
          exit $fail

  # ── The whole test surface, as a mcpp workspace ───────────────────────
  # mcpp-index is a mcpp [workspace]; every per-library test project under
  # tests/examples/ is a member. `mcpp test --workspace` builds + runs each
  # member's tests/ (behavioral assertions) on each OS — members self-gate by
  # `[target.'cfg(...)']` (e.g. the X11/glfw stack is linux-only, openblas is
  # windows-only), so one command covers the matrix with no shell driver.
  # The ~/.mcpp/registry cache carries the built compat packages (xpkgs) across
  # runs, so repeat builds are fast.
  #
  # timeout-minutes is sized for the COLD build, not the cached path. The opencv
  # module package carries a from-source OpenCV 5 build, and each feature variant
  # re-keys the store into a full recompile, so a full run (forced whenever this
  # workflow file changes — e.g. a version bump) serially builds three OpenCV
  # variants on one runner: the opencv-module base member plus the `unifont` and
  # `dnn` feature members. The registry cache (restore-keys prefix below)
  # amortizes those across subsequent runs. 150 covers the one-time cold full
  # build with headroom; it is a ceiling, not a target.
  # ── The plan, computed ONCE ───────────────────────────────────────────
  # Was inlined in every workspace job — three runners each re-deriving the
  # same answer. It now also has to be decided BEFORE the matrix exists,
  # because the matrix's shard dimension depends on it: a full run fans out,
  # a selective one does not.
  select:
    runs-on: ubuntu-latest
    outputs:
      members: ${{ steps.fanout.outputs.members }}
      matrix:  ${{ steps.fanout.outputs.matrix }}
      plan:    ${{ steps.plan_shards.outputs.plan }}
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      - name: Install lua
        run: sudo apt-get install -y --no-install-recommends lua5.4
      # ── Selective member testing ──────────────────────────────────────
      # `mcpp test --workspace` builds every member (opencv, ffmpeg, …) and
      # dominates CI wall-clock, while a PR almost always touches one
      # package. Map changed files → affected members and test only those:
      #   pkgs/<x>/<lib>.lua    → members whose mcpp.toml references <lib>
      #   tests/examples/<m>/** → member <m>
      # Run the FULL workspace when the change can affect everything:
      # non-PR events (push to main, the nightly cron, dispatch), this
      # workflow file (it carries the mcpp version pins, so a version bump
      # always re-validates every package), a non-member edit to the
      # workspace manifest, or shared test scripts. Docs-only and tools/-only
      # changes select nothing.
      # Note: bash 3.2 on macOS runners — no associative arrays here.
      - name: Select affected workspace members
        id: plan
        shell: bash
        run: |
          full() { echo "MEMBERS=__ALL__" >> "$GITHUB_ENV"; echo "full run: $1"; exit 0; }
          [ "${{ github.event_name }}" = "pull_request" ] || full "event=${{ github.event_name }}"
          base="origin/${{ github.base_ref }}"
          changed=$(git diff --name-only "$base"...HEAD)
          printf 'changed files vs %s:\n%s\n' "$base" "$changed"
          sel=""
          add() { case " $sel " in *" $1 "*) ;; *) sel="$sel $1" ;; esac; }
          while IFS= read -r f; do
            [ -n "$f" ] || continue
            case "$f" in
              .github/workflows/validate.yml|tests/*.sh) full "$f" ;;
              mcpp.toml)
                # Workspace manifest. Every new-package PR appends to the
                # members list, so that alone must NOT force a full run:
                # select the added members; anything else in this file
                # (indices, settings) affects everyone → full.
                if ! diff -q <(git show "$base:mcpp.toml" | grep -v 'tests/examples/') \
                             <(grep -v 'tests/examples/' mcpp.toml) >/dev/null; then
                  full "mcpp.toml non-member change"
                fi
                for p in $(comm -13 <(git show "$base:mcpp.toml" | grep -o 'tests/examples/[A-Za-z0-9._-]*' | sort -u) \
                                    <(grep -o 'tests/examples/[A-Za-z0-9._-]*' mcpp.toml | sort -u)); do
                  add "${p#tests/examples/}"
                done ;;
              tests/examples/*)
                m=${f#tests/examples/}; m=${m%%/*}
                # A deleted/renamed member dir implies a mcpp.toml edit,
                # which already forces a full run above.
                [ -d "tests/examples/$m" ] && add "$m" ;;
              pkgs/*.lua|pkgs/*/*.lua)
                lib=$(basename "$f" .lua); lib=${lib#compat.}
                hit=0
                for mt in tests/examples/*/mcpp.toml; do
                  if grep -q "$lib" "$mt"; then add "$(basename "$(dirname "$mt")")"; hit=1; fi
                done
                [ "$hit" = 1 ] || echo "note: no workspace member exercises $f" ;;
              # tools/ holds OFFLINE descriptor-generation and publishing
              # helpers (tools/compat-*/, tools/gtc/, publish_mcpp_index.sh).
              # Nothing under it is consumed by a package build: when one of
              # them actually changes a package, the generated pkgs/*.lua
              # changes with it and the rule above selects the right members.
              # So a tools/ edit alone selects nothing rather than forcing a
              # full workspace rebuild.
              *.md|docs/*|.agents/*|.github/*|tools/*) : ;;
              *) full "unclassified change: $f" ;;
            esac
          done <<EOF
          $changed
          EOF
          sel=${sel# }
          echo "MEMBERS=$sel" >> "$GITHUB_ENV"
          echo "selected members: ${sel:-<none>}"
      # Sharding is for the FULL run only, and the shard count per platform is
      # that platform's RUNNER CONCURRENCY — not a round number.
      #
      # Measured on this repo (24 jobs queued, 6 running):
      #     macos 1 · linux 3 · windows 2
      #
      # That measurement is what makes over-sharding a real cost rather than a
      # theoretical one: at concurrency 1, eight macOS shards run BACK TO BACK
      # and each pays its own checkout + mcpp download + cache restore, so the
      # split is strictly slower than not splitting. Wall-clock is
      # ceil(shards / concurrency) x slowest-shard; shards beyond the
      # concurrency only add fixed cost.
      #
      # Re-measure with:
      #   gh api repos/<owner>/<repo>/actions/runs/<id>/jobs --paginate \
      #     --jq '[.jobs[]|select(.status=="in_progress")]|length'
      - name: Decide the fan-out
        id: fanout
        shell: bash
        run: |
          full=0; [ "$MEMBERS" = "__ALL__" ] && full=1
          emit() {   # platform os suffix ext mcpp xlings shards
            for i in $(seq 0 $(( $7 - 1 ))); do
              printf '{"platform":"%s","os":"%s","suffix":"%s","ext":"%s","mcpp":"%s","xlings":"%s","shard":%d,"shards":%d},' \
                     "$1" "$2" "$3" "$4" "$5" "$6" "$i" "$7"
            done
          }
          if [ "$full" = 1 ]; then ln=3; mn=1; wn=2; else ln=1; mn=1; wn=1; fi
          {
            printf '{"include":['
            emit linux   ubuntu-latest  linux-x86_64   tar.gz bin/mcpp     registry/bin/xlings     "$ln"
            emit macos   macos-15       macosx-arm64   tar.gz bin/mcpp     registry/bin/xlings     "$mn"
            emit windows windows-latest windows-x86_64 zip    bin/mcpp.exe registry/bin/xlings.exe "$wn"
            printf ']}'
          } | sed 's/,]}/]}/' > /tmp/matrix.json
          echo "matrix=$(cat /tmp/matrix.json)" >> "$GITHUB_OUTPUT"
          echo "members=$MEMBERS" >> "$GITHUB_OUTPUT"
          cat /tmp/matrix.json

      # The split is computed ONCE, here, and shipped to the runners as data.
      # It used to run on each runner, which needed lua5.4 on all three
      # platforms — windows has no apt or brew, and macOS's brew installs
      # `lua`, not `lua5.4`, so every non-linux shard died with
      # `lua5.4: command not found` after 16 seconds. Deciding once is also
      # simply correct: one plan, not three runners each re-deriving it.
      - name: Plan the shards
        id: plan_shards
        shell: bash
        run: |
          plan='${{ steps.fanout.outputs.members }}'
          [ "$plan" = "__ALL__" ] && plan=""
          {
            printf '{'
            first=1
            for spec in linux:$(jq -r '[.include[]|select(.platform=="linux")]|length' /tmp/matrix.json) \
                        macos:$(jq -r '[.include[]|select(.platform=="macos")]|length' /tmp/matrix.json) \
                        windows:$(jq -r '[.include[]|select(.platform=="windows")]|length' /tmp/matrix.json); do
              p=${spec%%:*}; n=${spec##*:}
              [ "$first" = 1 ] || printf ','
              first=0
              printf '"%s":{' "$p"
              for i in $(seq 0 $((n - 1))); do
                [ "$i" = 0 ] || printf ','
                m=$(lua5.4 tests/plan_shards.lua "$p" "$i" "$n" $plan)
                printf '"%s":"%s"' "$i" "$m"
              done
              printf '}'
            done
            printf '}'
          } > /tmp/plan.json
          echo "plan=$(cat /tmp/plan.json)" >> "$GITHUB_OUTPUT"
          jq . /tmp/plan.json

  workspace:
    # The shard suffix appears only when the platform is actually split.
    name: workspace (${{ matrix.platform }}${{ matrix.shards == 1 && '' || format(' {0}/{1}', matrix.shard, matrix.shards) }})
    needs: select
    if: needs.select.outputs.members != ''
    runs-on: ${{ matrix.os }}
    # One shard is a fraction of the work, so this is a real ceiling rather
    # than the thing that decides whether the job finishes (a full linux run
    # used to hit 150 exactly and get cancelled).
    timeout-minutes: 90
    strategy:
      fail-fast: false
      # Whole matrix from `select`: the shard count is per-platform, because it
      # tracks that platform's runner concurrency.
      matrix: ${{ fromJSON(needs.select.outputs.matrix) }}
    steps:
      # Full history: the member-selection step below diffs against the PR
      # base to decide which workspace members to test.
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      # The cache key is computed ONCE, here, instead of inline in the cache
      # step. `hashFiles()` globs the WORKING TREE, and actions/cache
      # re-evaluates its `key` in the post (save) step — i.e. AFTER the build,
      # when `tests/**` no longer matches 80-odd tracked sources but tens of
      # thousands of build-output files under tests/examples/*/target and
      # .mcpp (multi-GB; .gitignore does not apply to hashFiles). Hashing that
      # tree blew past the runner's 120s template-evaluation cap on windows
      # and failed an otherwise all-green job:
      #   "hashFiles('pkgs/**/*.lua, tests/**, .github/workflows/validate.yml')
      #    couldn't finish within 120 seconds"
      # `git ls-files -s` reads the INDEX, so it sees exactly the tracked
      # inputs, never build output, and reports blob SHAs git already has —
      # no file content is read at all. Freezing the result in the job env
      # also guarantees the save step keys on the same string the restore
      # step used, no matter what the build left behind.
      - name: Compute registry cache key
        shell: bash
        run: |
          # git hash-object rather than sha256sum/cut: git is already a hard
          # requirement here (checkout ran), coreutils on the windows leg is
          # only a Git-Bash convenience.
          h=$(git ls-files -s -- 'pkgs/**/*.lua' 'tests/**' '.github/workflows/validate.yml' \
              | git hash-object --stdin)
          echo "REGISTRY_CACHE_KEY=mcpp-registry-${{ runner.os }}-${{ env.MCPP_VERSION }}-$h" >> "$GITHUB_ENV"
      - name: Restore mcpp registry cache
        uses: actions/cache@v4
        with:
          # Holds toolchains AND the built compat packages (data/xpkgs), so a
          # repeat `mcpp test` rebuilds little.
          path: ~/.mcpp/registry
          key: ${{ env.REGISTRY_CACHE_KEY }}
          restore-keys: |
            mcpp-registry-${{ runner.os }}-${{ env.MCPP_VERSION }}-
      - name: Download mcpp
        shell: bash
        env:
          MCPP_ARCHIVE: mcpp-${{ env.MCPP_VERSION }}-${{ matrix.suffix }}.${{ matrix.ext }}
          MCPP_ROOT: mcpp-${{ env.MCPP_VERSION }}-${{ matrix.suffix }}
        run: |
          curl -L -fsS -o "$MCPP_ARCHIVE" \
            "https://github.com/mcpp-community/mcpp/releases/download/v${MCPP_VERSION}/${MCPP_ARCHIVE}"
          case "$MCPP_ARCHIVE" in
            *.zip) powershell -NoProfile -Command "Expand-Archive -Force -Path '${MCPP_ARCHIVE}' -DestinationPath '.'" ;;
            *)     tar -xzf "$MCPP_ARCHIVE" ;;
          esac
          root="$PWD/$MCPP_ROOT"
          mkdir -p "$HOME/.mcpp/registry"
          cp -a "$root/registry/." "$HOME/.mcpp/registry/"
          if [[ "$RUNNER_OS" == "Windows" ]]; then
            echo "MCPP=$(cygpath -m "$root/${{ matrix.mcpp }}")" >> "$GITHUB_ENV"
            echo "MCPP_VENDORED_XLINGS=$(cygpath -m "$root/${{ matrix.xlings }}")" >> "$GITHUB_ENV"
            echo "$(cygpath -m "$root/bin")" >> "$GITHUB_PATH"
          else
            echo "MCPP=$root/${{ matrix.mcpp }}" >> "$GITHUB_ENV"
            echo "MCPP_VENDORED_XLINGS=$root/${{ matrix.xlings }}" >> "$GITHUB_ENV"
            echo "$root/bin" >> "$GITHUB_PATH"
          fi
      # compat.ffmpeg / compat.opencv5 carry NASM .asm sources. No host
      # install and no index-refresh pre-step needed: mcpp >= 0.0.97
      # resolves nasm itself through the same synchronous gate as the
      # toolchain (index refresh + install + payload check BEFORE the build
      # plans, mcpp#232). The sandbox copy lands in ~/.mcpp/registry, so
      # the cache carries it across runs.

      # ── This shard's slice of the plan ────────────────────────────────
      # `select` decided WHAT runs; this decides which part of it runs HERE.
      # Round-robin by position, which is what spreads the expensive members:
      # opencv-module / -dnn / -unifont are adjacent in the list, so `% N`
      # necessarily puts them on three different runners. A single job that
      # builds all three spends 45+ minutes on opencv alone.
      # ── This shard's slice ────────────────────────────────────────────
      # Already decided by `select` (measured-time bin packing, see
      # tests/plan_shards.lua). Arrives as data, so a runner needs no lua.
      - name: Take this shard's members
        shell: bash
        run: |
          mine='${{ fromJSON(needs.select.outputs.plan)[matrix.platform][format('{0}', matrix.shard)] }}'
          echo "MEMBERS=$mine" >> "$GITHUB_ENV"
          echo "shard ${{ matrix.shard }}/${{ matrix.shards }}: ${mine:-<none>}"

      # ── Refresh the PUBLISHED index before testing ────────────────────
      # Most members resolve everything from this checkout, but a member that
      # redirects a namespace other than `compat` gets the REST from the
      # published index — and nothing here ever refreshed it. The snapshot in
      # play is whatever the pinned mcpp release vendored (the Download step
      # `cp -a`s the release's registry/ over ~/.mcpp/registry, on top of the
      # restored cache), so it is by construction older than main, and it
      # never moves: the cache is saved with that same stale copy inside it.
      #
      # mcpp does refresh on a miss for a DIRECT dependency, which is why this
      # went unnoticed — the gap is a Form-A package's TRANSITIVE dependency.
      # tests/examples/godot-cpp-module hit it head-on: the module package's
      # own compat.godot-cpp dep resolved against a snapshot predating the
      # commit that added it, and failed with `index: local index <sha> (never
      # refreshed)` even though the artifact had already been republished.
      # (Older members never noticed: their compat packages have been in the
      # index far longer than any snapshot.)
      - name: Refresh the published package index
        shell: bash
        env:
          MCPP_INDEX_MIRROR: GLOBAL
        run: |
          "$MCPP" index update

      - name: mcpp test (workspace or affected members)
        shell: bash
        env:
          MCPP_INDEX_MIRROR: GLOBAL
          # The GLOBAL package build cache is on (mcpp >= 2026.7.30.2), which
          # is the default — this step used to set `MCPP_BUILD_CACHE: local`
          # and no longer does.
          #
          # That bypass existed for mcpp#344: object-path disambiguation fires
          # on basename collisions across the WHOLE build dir — i.e. on what
          # the CONSUMER pulls in — while the cache key covered only the
          # dependency, so one entry could hold two layouts and ninja died at
          # graph time with "missing and no known rule to make it". #344
          # landed in 2026.8.3.4 with per-package Merkle keys that cover the
          # consumer-dependent layout, so the reason is gone.
          #
          # Keeping it cost real time, and the full run is where it showed:
          # with `local`, EVERY member recompiles EVERY dependency from
          # scratch. 59 members that mostly share abseil / protobuf / opencv
          # meant the same sources were built over and over —
          #
          #   linux    2h30m -> cancelled at the 150-minute timeout
          #   windows  2h20m
          #   macos    1h26m
          #
          # — and a workspace cannot be validated by a job that cannot finish.
          # With the cache on, a given (package, version, features, toolchain)
          # is built once per run and every later member hits it.
        run: |
          "$MCPP" --version
          # No `timeout` wrapper: absent on macOS runners; job-level timeout-minutes bounds it.
          # One code path: the shard step above already expanded `__ALL__`
          # into this runner's actual member names, so `mcpp test --workspace`
          # — which would ignore the sharding and rebuild everything here — is
          # gone.
          #
          # tests/run_members.sh is the SAME script you run locally. A timing
          # table that only exists in CI cannot be used while deciding what to
          # optimise, and a local harness that differs from CI measures
          # something else.
          if [ -z "$MEMBERS" ]; then
            echo "No workspace member affected by this change — nothing to test."
          else
            MCPP_TIMINGS="$PWD/timings.tsv" bash tests/run_members.sh $MEMBERS
          fi

      # Per-shard timings, merged by the `timings` job below. `always()`: a
      # run that failed is exactly when knowing where the time went matters.
      - name: Upload this shard's timings
        if: always() && hashFiles('timings.tsv') != ''
        uses: actions/upload-artifact@v4
        with:
          name: timings-${{ matrix.platform }}-${{ matrix.shard }}
          path: timings.tsv
          retention-days: 14

      # install()-driven packages (openssl, openblas) build through their own
      # Make/Configure system, whose output xim's interface mode swallows; a
      # failed hook surfaces only as `E_INTERNAL: [<pkg>] failed:`. Each writes
      # a log into its install prefix, so on failure surface those — otherwise
      # diagnosing a platform-specific build break costs a full CI round-trip
      # per guess.
      - name: Dump install() build logs on failure
        if: failure()
        shell: bash
        run: |
          found=0
          while IFS= read -r log; do
            found=1
            echo "::group::$log"
            tail -80 "$log"
            echo "::endgroup::"
          done < <(find tests/examples "$HOME/.mcpp/registry" -name 'mcpp_*_build.log' 2>/dev/null)
          [ "$found" = 1 ] || echo "no install() build logs found"

  # ── Where the time went ───────────────────────────────────────────────
  # Sharding hides the cost: eight runners each report their own slice, and
  # nobody can see which members actually dominate. This merges them into one
  # ranking per platform, in the run summary, so the next optimisation starts
  # from measurement instead of a guess.
  #
  # `always()` — a failed run is exactly when this is worth reading.
  timings:
    needs: [select, workspace]
    if: always() && needs.select.outputs.members != ''
    runs-on: ubuntu-latest
    steps:
      - uses: actions/download-artifact@v4
        with:
          pattern: timings-*
          path: timings
        continue-on-error: true
      - name: Rank members by wall-clock
        shell: bash
        run: |
          shopt -s nullglob
          files=(timings/*/timings.tsv)
          if [ ${#files[@]} -eq 0 ]; then
            echo "no timing data (every shard skipped or failed before testing)" \
              >> "$GITHUB_STEP_SUMMARY"
            exit 0
          fi

          # Artifact name carries the platform: timings-<platform>-<shard>.
          for plat in linux macos windows; do
            rows=$(mktemp)
            for f in timings/timings-$plat-*/timings.tsv; do
              [ -f "$f" ] && cat "$f" >> "$rows"
            done
            [ -s "$rows" ] || { rm -f "$rows"; continue; }

            total=$(awk -F'\t' '{s += $1} END {print s+0}' "$rows")
            count=$(wc -l < "$rows")
            {
              echo "### $plat — ${count} member(s), ${total}s of member wall-clock"
              echo
              echo "| rank | seconds | share | member | result |"
              echo "|---:|---:|---:|---|---|"
              sort -rn "$rows" | awk -F'\t' -v tot="$total" '
                { pct = tot > 0 ? ($1 * 100 / tot) : 0
                  printf "| %d | %s | %.1f%% | `%s` | %s |\n", NR, $1, pct, $2, $3 }'
              echo
            } >> "$GITHUB_STEP_SUMMARY"
            rm -f "$rows"
          done

          echo "_Total is the SUM across shards; wall-clock is the slowest shard._" \
            >> "$GITHUB_STEP_SUMMARY"

          # The table that feeds the NEXT run's sharding. Emitted as an
          # artifact rather than committed automatically: a number that
          # rewrites itself on every run would make every diff noisy and would
          # silently absorb a one-off slow runner. Refresh it deliberately —
          # download this artifact and replace tests/member-timings.tsv when
          # the numbers have actually moved.
          {
            echo "# <platform>\t<member>\t<seconds> — from run ${{ github.run_id }}"
            echo "# refresh: download the member-timings artifact and replace this file"
            for plat in linux macos windows; do
              for f in timings/timings-$plat-*/timings.tsv; do
                [ -f "$f" ] || continue
                awk -F'\t' -v p="$plat" '{ printf "%s\t%s\t%s\n", p, $2, $1 }' "$f"
              done
            done
          } | sort -u > member-timings.tsv
          echo "wrote member-timings.tsv ($(grep -vc '^#' member-timings.tsv) rows)"

      - name: Upload the timing table for the next run's sharding
        if: always() && hashFiles('member-timings.tsv') != ''
        uses: actions/upload-artifact@v4
        with:
          name: member-timings
          path: member-timings.tsv
          retention-days: 90