Script to generate html report for Bazel C/C++ projects on Linux

BUILD

package(default_visibility = ["//visibility:public"])

sh_binary(
    name = "coverage_linux",
    srcs = ["coverage_linux.sh"],
    exec_compatible_with = ["@platforms//os:linux"],
    tags = [
        "block-network",
        "local",
        "no-cache",
    ],
    target_compatible_with = ["@platforms//os:linux"],
)

coverage_linux.sh

#!/bin/bash -e

# parse args
usage() {
    echo "Usage: $0 [-g genhtml] [-l lcov] [-o coverage]" 1>&2;
    echo "   -g  Path to genhtml tool" 1>&2;
    echo "   -l  Path to lcov tool" 1>&2;
    echo "   -o  Output coverage folder" 1>&2;
    exit 1;
}
while getopts ":g:l:o:" o; do
    case "${o}" in
        g)
            GENHTML_PATH=${OPTARG}
            ;;
        p)
            LCOV_PATH=${OPTARG}
            ;;
        o)
            COVERAGE_DIR=${OPTARG}
            ;;
        *)
            usage
            ;;
    esac
done
shift $((OPTIND-1))

# if variable is not set, hope tool is available in PATH
# https://stackoverflow.com/a/28085062/1953079
: "${GENHTML_PATH:=genhtml}"
: "${LCOV_PATH:=lcov}"
: "${COVERAGE_DIR:=coverage}"

if [ -z "$BUILD_WORKSPACE_DIRECTORY" ]; then
    echo "BUILD_WORKSPACE_DIRECTORY is not defined. "
    echo "You can run this tool only under `bazel run`"
    exit 1
fi

cd $BUILD_WORKSPACE_DIRECTORY

# check if `bazel test` was executed
DATFILES=$(find bazel-testlogs/ -type f -name "coverage.dat" -size +0 | wc -l)
if (($DATFILES == 0 )); then
    echo "#####################################"
    echo "#      NO COVERAGE DATA FOUND       #"
    echo "#####################################"
    echo "Cannot find \"coverage.dat\" under bazel-testlogs dir."
    echo "Did you run \"bazel test\"?"
    exit 1
fi

TMP=tmp.merged.lcov.info
# always cleanup tmp file
trap "rm ${TMP}" EXIT

# merge all coverage.dat files (one per test)
echo "#####################################"
echo "#   MERGE COVERAGE FROM ALL TESTS   #"
echo "#####################################"
LCOV_INPUT_FILES=""
while read FILENAME; do
    LCOV_INPUT_FILES="$LCOV_INPUT_FILES -a \"$FILENAME\""
done < <( find bazel-testlogs/ -type f -name "coverage.dat" -size +0 )
eval "${LCOV_PATH}" "${LCOV_INPUT_FILES}" -o ${TMP}

# generate html report
echo "####################################"
echo "#       GENERATE HTML REPORT       #"
echo "####################################"
eval "${GENHTML_PATH}" -o ${COVERAGE_DIR} ${TMP}

usage.txt

bazel run //:coverage_linux
bazel run //:coverage_linux -- -o outputdir -g $genhtml_path -l $lcov_path