pre-push-coverage

#!/bin/sh
#
# Pre-push hook: checks that a fresh coverage report exists
# when pushing coprocessor changes. Non-blocking (always exits 0).
#

# Preserve Git LFS functionality
command -v git-lfs >/dev/null 2>&1 && git lfs pre-push "$@"

# Get the repo root
REPO_ROOT=$(git rev-parse --show-toplevel)
REPORT_FILE="$REPO_ROOT/coprocessor/fhevm-engine/coverage-report.txt"
COPROCESSOR_DIR="coprocessor/fhevm-engine/"

# Fetch latest remote to ensure accurate comparison
git fetch origin main --quiet 2>/dev/null || true

# Get changed files on this branch vs origin/main, filtered to actual crate directories only
# (ignores root-level config: Makefile, scripts/, Cargo.toml, etc.)
CRATE_CHANGES=$(git diff --name-only "origin/main"...HEAD -- "$COPROCESSOR_DIR" 2>/dev/null | \
    while read -r f; do
        rel=$(echo "$f" | sed "s|^$COPROCESSOR_DIR||")
        crate_name=$(echo "$rel" | cut -d/ -f1)
        if [ -f "$REPO_ROOT/$COPROCESSOR_DIR$crate_name/Cargo.toml" ]; then
            echo "$crate_name"
        fi
    done | sort -u)

if [ -z "$CRATE_CHANGES" ]; then
    exit 0
fi

# Check if coverage report exists
if [ ! -f "$REPORT_FILE" ]; then
    echo ""
    echo "WARNING: No coverage report found for coprocessor."
    echo "  Run 'make coverage-changed' in coprocessor/fhevm-engine/ to generate it."
    echo ""
    exit 0
fi

# Check report freshness via embedded commit hash
REPORT_COMMIT=$(grep "^# commit:" "$REPORT_FILE" 2>/dev/null | awk '{print $3}')
if [ -z "$REPORT_COMMIT" ]; then
    echo ""
    echo "WARNING: Coverage report has no commit metadata (regenerate with latest tooling)."
    echo "  Run 'make coverage-changed' in coprocessor/fhevm-engine/ to regenerate."
    echo ""
    exit 0
fi

# Get the latest crate-related commit on this branch
LATEST_CRATE_COMMIT=""
for crate in $CRATE_CHANGES; do
    c=$(git log -1 --format=%H "origin/main"..HEAD -- "$COPROCESSOR_DIR$crate/" 2>/dev/null)
    if [ -n "$c" ]; then
        if [ -z "$LATEST_CRATE_COMMIT" ] || [ "$(git log -1 --format=%ct "$c")" -gt "$(git log -1 --format=%ct "$LATEST_CRATE_COMMIT")" ]; then
            LATEST_CRATE_COMMIT="$c"
        fi
    fi
done

if [ -z "$LATEST_CRATE_COMMIT" ]; then
    exit 0
fi

# Check if the report was generated at or after the latest crate commit
if ! git merge-base --is-ancestor "$LATEST_CRATE_COMMIT" "$REPORT_COMMIT" 2>/dev/null; then
    echo ""
    echo "WARNING: Coverage report is stale (generated before latest coprocessor commit)."
    echo "  Run 'make coverage-changed' in coprocessor/fhevm-engine/ to regenerate."
    echo ""
    exit 0
fi

# Report is fresh — print summary
TOTAL_LINE=$(grep "^TOTAL" "$REPORT_FILE" 2>/dev/null)
if [ -n "$TOTAL_LINE" ]; then
    REGION_PCT=$(echo "$TOTAL_LINE" | awk '{print $4}')
    FUNC_PCT=$(echo "$TOTAL_LINE" | awk '{print $7}')
    LINE_PCT=$(echo "$TOTAL_LINE" | awk '{print $10}')
    echo ""
    echo "Coverage: Lines: $LINE_PCT | Functions: $FUNC_PCT | Regions: $REGION_PCT"
    echo ""
fi

exit 0