Merge pull request #241184 from SuperSandro2000/matrix-no-test-parallel

  doCheck = !stdenv.isDarwin;

  checkPhase = let testFlags = lib.optionalString (!stdenv.isAarch64) "-j $NIX_BUILD_CORES"; in ''

  checkPhase = ''

    runHook preCheck

    # remove src module, so tests use the installed module instead

    rm -rf ./synapse

    PYTHONPATH=".:$PYTHONPATH" ${python3.interpreter} -m twisted.trial ${testFlags} tests

    # high parallelisem makes test suite unstable

    # upstream uses 2 cores but 4 seems to be also stable

    # https://github.com/matrix-org/synapse/blob/develop/.github/workflows/latest_deps.yml#L103

    if (( $NIX_BUILD_CORES > 4)); then

      NIX_BUILD_CORES=4

    fi

    PYTHONPATH=".:$PYTHONPATH" ${python3.interpreter} -m twisted.trial -j $NIX_BUILD_CORES tests

    runHook postCheck

  '';

  passthru.tests = { inherit (nixosTests) matrix-synapse; };

  passthru.plugins = plugins;

  passthru.tools = tools;

  passthru.python = python3;

  passthru = {

    tests = { inherit (nixosTests) matrix-synapse; };

    inherit plugins tools;

    python = python3;

  };

  meta = with lib; {

    homepage = "https://matrix.org";