ci.yml

name: CI

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  count-checks:
    name: Sorry / axiom count
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Count sorries against docs/SORRY_CATALOG.md
        run: |
          # Tightened regex: match only standalone `sorry` (line is exactly
          # whitespace-then-sorry-then-whitespace), `by sorry`, `:= sorry`.
          # Excludes docstring text like "sorry'd" or "left as sorry".
          ACTUAL=$(grep -rnE "^[[:space:]]*sorry[[:space:]]*$|by sorry|:= sorry" \
            --include="*.lean" \
            OpenGALib \
            2>/dev/null | wc -l | tr -d ' ')
          EXPECTED=36
          if [ "$ACTUAL" -ne "$EXPECTED" ]; then
            echo "::error::Sorry count drift: expected $EXPECTED, found $ACTUAL"
            echo "If the change is intentional, update docs/SORRY_CATALOG.md (and the EXPECTED constant in this workflow)."
            echo "If unintentional, close the new sorry or revert the regression."
            exit 1
          fi
          echo "Sorry count: $ACTUAL (matches docs/SORRY_CATALOG.md)"

      - name: Count axioms (expect zero)
        run: |
          # Match only true axiom declarations: `axiom <ident>` at start of line,
          # nothing trailing. Excludes docstring text where 'axiom' may begin a
          # wrapped sentence (e.g., `axiom about CovariantDerivative wrapping`).
          ACTUAL=$(grep -rnE "^axiom[[:space:]]+[a-zA-Z_][a-zA-Z0-9_']*[[:space:]]*$" \
            --include="*.lean" \
            OpenGALib \
            2>/dev/null | wc -l | tr -d ' ')
          EXPECTED=0
          if [ "$ACTUAL" -ne "$EXPECTED" ]; then
            echo "::error::Axiom count drift: expected $EXPECTED, found $ACTUAL"
            echo "If the change is intentional, document the axiom in module docstrings (and update the EXPECTED constant in this workflow)."
            echo "If unintentional, close the new axiom or revert the regression."
            exit 1
          fi
          echo "Axiom count: $ACTUAL"

  build:
    name: Lake build
    runs-on: ubuntu-latest
    timeout-minutes: 60
    steps:
      - uses: actions/checkout@v4

      - name: Install elan (Lean toolchain manager)
        run: |
          curl https://raw.githubusercontent.com/leanprover/elan/master/elan-init.sh -sSf | sh -s -- -y --default-toolchain none
          echo "$HOME/.elan/bin" >> "$GITHUB_PATH"

      - name: Print Lean version
        run: lean --version

      # Cache the FULL Lake build: Mathlib oleans (via `lake exe cache get`),
      # OpenGALib oleans (incremental — Lake re-elaborates only changed
      # files + transitive deps), plus packages.  Key on
      # lake-manifest + toolchain so a Mathlib/toolchain bump invalidates.
      # Branch prefix in restore-keys allows in-PR cache reuse across pushes.
      - name: Cache .lake build artifacts
        uses: actions/cache@v4
        with:
          path: |
            .lake/build
            .lake/packages
          key: lake-${{ runner.os }}-${{ hashFiles('lake-manifest.json', 'lean-toolchain') }}-${{ github.sha }}
          restore-keys: |
            lake-${{ runner.os }}-${{ hashFiles('lake-manifest.json', 'lean-toolchain') }}-
            lake-${{ runner.os }}-

      # `lake exe cache get` pulls Mathlib oleans from Mathlib's own artifact
      # cache.  Safe no-op on cache hit; fast (~10 s) on cache miss.
      - name: Get Mathlib build cache
        run: lake exe cache get
        continue-on-error: true

      # Incremental build: Lake re-elaborates only the files that changed in
      # this PR plus their transitive downstream consumers.  Linter warnings
      # only fire for files that re-elaborate, but since all linter baselines
      # are 0 (no untouched-file false-positive risk), this is the right
      # trade-off — fast PR feedback (~30 s on warm cache) while still
      # catching every new violation.
      - name: Build OpenGALib (capture linter output)
        run: |
          set -o pipefail
          lake build 2>&1 | tee /tmp/build.log

      - name: Enforce linter baselines
        run: |
          # Each Lean linter emits a distinct warning prefix; grep + count.
          # Only re-elaborated files emit warnings, but the EXPECTED
          # constants are all 0, so any new violation in changed files
          # (or their transitive consumers) fails CI.
          MATH_TAG=$(grep -c "docstring should start with" /tmp/build.log 2>/dev/null || echo 0)
          ANCHOR_PURITY=$(grep -c "in an anchor file" /tmp/build.log 2>/dev/null || echo 0)
          NAMING=$(grep -c "forbidden initialism" /tmp/build.log 2>/dev/null || echo 0)

          EXPECTED_MATH_TAG=0
          EXPECTED_ANCHOR_PURITY=0
          EXPECTED_NAMING=0

          echo "Linter baselines (re-elaborated files only):"
          echo "  MathTag:        $MATH_TAG (expected $EXPECTED_MATH_TAG)"
          echo "  AnchorPurity:   $ANCHOR_PURITY (expected ≤ $EXPECTED_ANCHOR_PURITY; gradually reduce)"
          echo "  Naming:         $NAMING (expected $EXPECTED_NAMING)"

          FAIL=0
          if [ "$MATH_TAG" -gt "$EXPECTED_MATH_TAG" ]; then
            echo "::error::MathTag linter regression: $MATH_TAG > $EXPECTED_MATH_TAG"
            echo "Every declaration with a docstring must begin with **Math.**, **Eng.**, or **Mixed.**"
            FAIL=1
          fi
          if [ "$ANCHOR_PURITY" -gt "$EXPECTED_ANCHOR_PURITY" ]; then
            echo "::error::AnchorPurity linter regression: $ANCHOR_PURITY > $EXPECTED_ANCHOR_PURITY"
            echo "Move the new Eng/Mixed declaration into the layer's Util/ sub-module,"
            echo "or update EXPECTED_ANCHOR_PURITY only when intentionally reducing the count."
            FAIL=1
          fi
          if [ "$NAMING" -gt "$EXPECTED_NAMING" ]; then
            echo "::error::Naming linter regression: $NAMING > $EXPECTED_NAMING"
            echo "Expand the initialism in the declaration name (CLM → ContinuousLinearMap, etc.)."
            FAIL=1
          fi
          exit $FAIL

      - name: Shake — unused-import baseline
        run: |
          # `lake exe shake` flags files with unused imports (and missing
          # transitive-relied-on imports). Baseline is current debt; CI
          # fails on growth, mirrors Mathlib's `noshake.json` discipline.
          ACTUAL=$(lake exe shake OpenGALib --no-downstream 2>&1 | grep -c "^/.*\.lean:$" || echo 0)
          EXPECTED_SHAKE=38
          echo "Shake suggestions: $ACTUAL (expected ≤ $EXPECTED_SHAKE; gradually reduce)"
          if [ "$ACTUAL" -gt "$EXPECTED_SHAKE" ]; then
            echo "::error::Shake regression: $ACTUAL > $EXPECTED_SHAKE"
            echo "Add the missing import to the consumer file, or update EXPECTED_SHAKE only when reducing."
            echo "Run \`lake exe shake OpenGALib --no-downstream\` locally to see the suggestions."
            exit 1
          fi

  # On main push, do a full-fresh elaboration to catch any linter regressions
  # that the incremental build missed (e.g., a regression hiding behind a
  # cached olean).  This is the safety net; PRs use incremental for speed.
  full-lint-on-main:
    name: Full lint baseline (main push only)
    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
    runs-on: ubuntu-latest
    timeout-minutes: 60
    steps:
      - uses: actions/checkout@v4

      - name: Install elan
        run: |
          curl https://raw.githubusercontent.com/leanprover/elan/master/elan-init.sh -sSf | sh -s -- -y --default-toolchain none
          echo "$HOME/.elan/bin" >> "$GITHUB_PATH"

      - name: Print Lean version
        run: lean --version

      # Restore cache so Mathlib doesn't re-download
      - name: Cache .lake build artifacts (Mathlib only)
        uses: actions/cache@v4
        with:
          path: |
            .lake/packages
          key: lake-mathlib-${{ runner.os }}-${{ hashFiles('lake-manifest.json', 'lean-toolchain') }}
          restore-keys: |
            lake-mathlib-${{ runner.os }}-

      - name: Get Mathlib build cache
        run: lake exe cache get
        continue-on-error: true

      # Force fresh OpenGALib elaboration to catch every linter warning
      - name: Build OpenGALib from scratch
        run: |
          set -o pipefail
          lake build 2>&1 | tee /tmp/build.log

      - name: Enforce linter baselines (fresh elaboration — authoritative)
        run: |
          MATH_TAG=$(grep -c "docstring should start with" /tmp/build.log 2>/dev/null || echo 0)
          ANCHOR_PURITY=$(grep -c "in an anchor file" /tmp/build.log 2>/dev/null || echo 0)
          NAMING=$(grep -c "forbidden initialism" /tmp/build.log 2>/dev/null || echo 0)

          echo "Linter baselines (fresh elaboration):"
          echo "  MathTag:        $MATH_TAG"
          echo "  AnchorPurity:   $ANCHOR_PURITY"
          echo "  Naming:         $NAMING"

          FAIL=0
          if [ "$MATH_TAG" -gt 0 ]; then echo "::error::MathTag regression: $MATH_TAG"; FAIL=1; fi
          if [ "$ANCHOR_PURITY" -gt 0 ]; then echo "::error::AnchorPurity regression: $ANCHOR_PURITY"; FAIL=1; fi
          if [ "$NAMING" -gt 0 ]; then echo "::error::Naming regression: $NAMING"; FAIL=1; fi
          exit $FAIL