pre-commit-hooks-test-case.sh

checkGitFile() {
    git ls-files --error-unmatch $1 > /dev/null 2>&1
}

# checking for test existence of files using react hooks
filesUsingHooks=$(git diff --cached --name-only --diff-filter=ACR | grep -l -E '^import.+\<use(State|Effect|Context|Reducer|Callback|Memo|Ref|ImperativeHandle|LayoutEffect|DebugValue)' --include \*.js --exclude \*.\*.js)

if [ -n "$filesUsingHooks" ]; then
    headline "Checking if your react hooks have tests"
    for fileUsingHooks in "$filesUsingHooks"
    do
        unitTestName=$(basename $(sed 's|\.js|\.spec\.js|' <<< "$fileUsingHooks"))
        checkGitFile "*/$unitTestName"
        if [[ $? != 0 ]]; then
            echo "No test found for $fileUsingHooks"
            echo "Please add a unit test named $unitTestName"
            exit 1
        fi
    done
fi

This is a git pre-commit hook preventing a new .js file from being added without a matching .spec.js file with a test case. Useful to introduce React hooks while increasing your test coverage.