============================= test session starts ==============================
platform linux -- Python 3.7.9, pytest-5.4.3, py-1.9.0, pluggy-0.13.1
rootdir: /build/rpy2-3.2.6
collected 692 items / 1 error / 691 selected                                   

==================================== ERRORS ====================================
______________ ERROR collecting rpy2/tests/ipython/test_ggplot.py ______________
rpy2/tests/ipython/test_ggplot.py:3: in <module>
    import rpy2.robjects.lib.ggplot2
rpy2/robjects/lib/ggplot2.py:57: in <module>
    lazyeval = importr('lazyeval', on_conflict='warn')
rpy2/robjects/packages.py:477: in importr
    env = _get_namespace(rname)
rpy2/rinterface_lib/conversion.py:40: in _
    cdata = function(*args, **kwargs)
rpy2/rinterface.py:789: in __call__
    raise embedded.RRuntimeError(_rinterface._geterrmessage())
E   rpy2.rinterface_lib.embedded.RRuntimeError: Error in loadNamespace(name) : there is no package called ‘lazyeval’
E   Calls: <Anonymous> ... loadNamespace -> withRestarts -> withOneRestart -> doWithOneRestart
------------------------------- Captured stderr --------------------------------
R[write to console]: Error in loadNamespace(name) : there is no package called ‘lazyeval’
Calls: <Anonymous> ... loadNamespace -> withRestarts -> withOneRestart -> doWithOneRestart

=============================== warnings summary ===============================
rpy2/robjects/pandas2ri.py:14
  /build/rpy2-3.2.6/rpy2/robjects/pandas2ri.py:14: FutureWarning: pandas.core.index is deprecated and will be removed in a future version.  The public classes are available in the top-level namespace.
    from pandas.core.index import Index as PandasIndex

rpy2/robjects/pandas2ri.py:34
  /build/rpy2-3.2.6/rpy2/robjects/pandas2ri.py:34: UserWarning: pandas >= 1.0 is not supported.
    warnings.warn('pandas >= 1.0 is not supported.')

-- Docs: https://docs.pytest.org/en/latest/warnings.html
=========================== short test summary info ============================
ERROR rpy2/tests/ipython/test_ggplot.py - rpy2.rinterface_lib.embedded.RRunti...
!!!!!!!!!!!!!!!!!!!! Interrupted: 1 error during collection !!!!!!!!!!!!!!!!!!!!
========================= 2 warnings, 1 error in 5.99s =========================
builder for '/nix/store/sp2533fydvzb3hdz414rkv3j3wvc39ri-python3.7-rpy2-3.2.6.drv' failed with exit code 2
cannot build derivation '/nix/store/p4kjkz23jj4p70wk5cmwq1576y26xkpq-python3-3.7.9-env.drv': 1 dependencies couldn't be built
error: build of '/nix/store/p4kjkz23jj4p70wk5cmwq1576y26xkpq-python3-3.7.9-env.drv' failed

with import <nixpkgs> {};
let
  envPy = python37.withPackages ( ps: with ps; [
    ipython 
    jupyterlab
    rpy2
  ]
  )
  ;
in mkShell {
  buildInputs = [
    (envPy)
    black
  ];
}

 - system: `"x86_64-linux"`
 - host os: `Linux 5.8.13, NixOS, 20.09beta992.7badbf18c45 (Nightingale)`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.3.7`
 - channels(root): `"nixos-20.09beta992.7badbf18c45"`
 - channels(user): `"nixos-20.09beta992.7badbf18c45"`
 - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos`