from numpy.testing import assert_equal, assert_array_equal, assert_allclose
from nose.tools import assert_true, assert_raises, assert_not_equal
from copy import deepcopy
import os.path as op
import numpy as np
from scipy import sparse
import os
import warnings

from mne import read_evokeds
from mne.datasets import testing
from mne.externals.six.moves import StringIO
from mne.io import show_fiff, read_raw_fif
from mne.epochs import _segment_raw
from mne.time_frequency import tfr_morlet
from mne.utils import (set_log_level, set_log_file, _TempDir,
                       get_config, set_config, deprecated, _fetch_file,
                       sum_squared, estimate_rank,
                       _url_to_local_path, sizeof_fmt, _check_subject,
                       _check_type_picks, object_hash, object_diff,
                       requires_good_network, run_tests_if_main, md5sum,
                       ArgvSetter, _memory_usage, check_random_state,
                       _check_mayavi_version, requires_mayavi,
                       set_memmap_min_size, _get_stim_channel, _check_fname,
                       create_slices, _time_mask, random_permutation,
                       _get_call_line, compute_corr, sys_info, verbose,
                       check_fname, requires_ftp, get_config_path,
                       object_size, buggy_mkl_svd, _get_inst_data,
                       copy_doc, copy_function_doc_to_method_doc)


warnings.simplefilter('always')  # enable b/c these tests throw warnings

base_dir = op.join(op.dirname(__file__), '..', 'io', 'tests', 'data')
fname_evoked = op.join(base_dir, 'test-ave.fif')
fname_raw = op.join(base_dir, 'test_raw.fif')
fname_log = op.join(base_dir, 'test-ave.log')
fname_log_2 = op.join(base_dir, 'test-ave-2.log')

data_path = testing.data_path(download=False)
fname_fsaverage_trans = op.join(data_path, 'subjects', 'fsaverage', 'bem',
                                'fsaverage-trans.fif')


def clean_lines(lines=[]):
    # Function to scrub filenames for checking logging output (in test_logging)
    return [l if 'Reading ' not in l else 'Reading test file' for l in lines]


def test_buggy_mkl():
    """Test decorator for buggy MKL issues"""
    from nose.plugins.skip import SkipTest

    @buggy_mkl_svd
    def foo(a, b):
        raise np.linalg.LinAlgError('SVD did not converge')
    with warnings.catch_warnings(record=True) as w:
        assert_raises(SkipTest, foo, 1, 2)
    assert_true(all('convergence error' in str(ww.message) for ww in w))

    @buggy_mkl_svd
    def bar(c, d, e):
        raise RuntimeError('SVD did not converge')
    assert_raises(RuntimeError, bar, 1, 2, 3)


def test_sys_info():
    """Test info-showing utility
    """
    out = StringIO()
    sys_info(fid=out)
    out = out.getvalue()
    assert_true('numpy:' in out)


def test_get_call_line():
    """Test getting a call line
    """
    @verbose
    def foo(verbose=None):
        return _get_call_line(in_verbose=True)

    for v in (None, True):
        my_line = foo(verbose=v)  # testing
        assert_equal(my_line, 'my_line = foo(verbose=v)  # testing')

    def bar():
        return _get_call_line(in_verbose=False)

    my_line = bar()  # testing more
    assert_equal(my_line, 'my_line = bar()  # testing more')


def test_object_size():
    """Test object size estimation"""
    assert_true(object_size(np.ones(10, np.float32)) <
                object_size(np.ones(10, np.float64)))
    for lower, upper, obj in ((0, 60, ''),
                              (0, 30, 1),
                              (0, 30, 1.),
                              (0, 60, 'foo'),
                              (0, 150, np.ones(0)),
                              (0, 150, np.int32(1)),
                              (150, 500, np.ones(20)),
                              (100, 400, dict()),
                              (400, 1000, dict(a=np.ones(50))),
                              (200, 900, sparse.eye(20, format='csc')),
                              (200, 900, sparse.eye(20, format='csr'))):
        size = object_size(obj)
        assert_true(lower < size < upper,
                    msg='%s < %s < %s:\n%s' % (lower, size, upper, obj))


def test_get_inst_data():
    """Test _get_inst_data"""
    raw = read_raw_fif(fname_raw, add_eeg_ref=False)
    raw.crop(tmax=1.)
    assert_equal(_get_inst_data(raw), raw._data)
    raw.pick_channels(raw.ch_names[:2])

    epochs = _segment_raw(raw, 0.5)
    assert_equal(_get_inst_data(epochs), epochs._data)

    evoked = epochs.average()
    assert_equal(_get_inst_data(evoked), evoked.data)

    evoked.crop(tmax=0.1)
    picks = list(range(2))
    freqs = np.array([50., 55.])
    n_cycles = 3
    tfr = tfr_morlet(evoked, freqs, n_cycles, return_itc=False, picks=picks)
    assert_equal(_get_inst_data(tfr), tfr.data)

    assert_raises(TypeError, _get_inst_data, 'foo')


def test_misc():
    """Test misc utilities"""
    assert_equal(_memory_usage(-1)[0], -1)
    assert_equal(_memory_usage((clean_lines, [], {}))[0], -1)
    assert_equal(_memory_usage(clean_lines)[0], -1)
    assert_raises(ValueError, check_random_state, 'foo')
    assert_raises(ValueError, set_memmap_min_size, 1)
    assert_raises(ValueError, set_memmap_min_size, 'foo')
    assert_raises(TypeError, get_config, 1)
    assert_raises(TypeError, set_config, 1)
    assert_raises(TypeError, set_config, 'foo', 1)
    assert_raises(TypeError, _get_stim_channel, 1, None)
    assert_raises(TypeError, _get_stim_channel, [1], None)
    assert_raises(TypeError, _check_fname, 1)
    assert_raises(IOError, check_fname, 'foo', 'tets-dip.x', (), ('.fif',))
    assert_raises(ValueError, _check_subject, None, None)
    assert_raises(ValueError, _check_subject, None, 1)
    assert_raises(ValueError, _check_subject, 1, None)


@requires_mayavi
def test_check_mayavi():
    """Test mayavi version check"""
    assert_raises(RuntimeError, _check_mayavi_version, '100.0.0')


def test_run_tests_if_main():
    """Test run_tests_if_main functionality"""
    x = []

    def test_a():
        x.append(True)

    @np.testing.dec.skipif(True)
    def test_b():
        return

    try:
        __name__ = '__main__'
        run_tests_if_main(measure_mem=False)  # dual meas causes problems

        def test_c():
            raise RuntimeError

        try:
            __name__ = '__main__'
            run_tests_if_main(measure_mem=False)  # dual meas causes problems
        except RuntimeError:
            pass
        else:
            raise RuntimeError('Error not raised')
    finally:
        del __name__
    assert_true(len(x) == 2)
    assert_true(x[0] and x[1])


def test_hash():
    """Test dictionary hashing and comparison functions"""
    # does hashing all of these types work:
    # {dict, list, tuple, ndarray, str, float, int, None}
    d0 = dict(a=dict(a=0.1, b='fo', c=1), b=[1, 'b'], c=(), d=np.ones(3),
              e=None)
    d0[1] = None
    d0[2.] = b'123'

    d1 = deepcopy(d0)
    assert_true(len(object_diff(d0, d1)) == 0)
    assert_true(len(object_diff(d1, d0)) == 0)
    assert_equal(object_hash(d0), object_hash(d1))

    # change values slightly
    d1['data'] = np.ones(3, int)
    d1['d'][0] = 0
    assert_not_equal(object_hash(d0), object_hash(d1))

    d1 = deepcopy(d0)
    assert_equal(object_hash(d0), object_hash(d1))
    d1['a']['a'] = 0.11
    assert_true(len(object_diff(d0, d1)) > 0)
    assert_true(len(object_diff(d1, d0)) > 0)
    assert_not_equal(object_hash(d0), object_hash(d1))

    d1 = deepcopy(d0)
    assert_equal(object_hash(d0), object_hash(d1))
    d1['a']['d'] = 0  # non-existent key
    assert_true(len(object_diff(d0, d1)) > 0)
    assert_true(len(object_diff(d1, d0)) > 0)
    assert_not_equal(object_hash(d0), object_hash(d1))

    d1 = deepcopy(d0)
    assert_equal(object_hash(d0), object_hash(d1))
    d1['b'].append(0)  # different-length lists
    assert_true(len(object_diff(d0, d1)) > 0)
    assert_true(len(object_diff(d1, d0)) > 0)
    assert_not_equal(object_hash(d0), object_hash(d1))

    d1 = deepcopy(d0)
    assert_equal(object_hash(d0), object_hash(d1))
    d1['e'] = 'foo'  # non-None
    assert_true(len(object_diff(d0, d1)) > 0)
    assert_true(len(object_diff(d1, d0)) > 0)
    assert_not_equal(object_hash(d0), object_hash(d1))

    d1 = deepcopy(d0)
    d2 = deepcopy(d0)
    d1['e'] = StringIO()
    d2['e'] = StringIO()
    d2['e'].write('foo')
    assert_true(len(object_diff(d0, d1)) > 0)
    assert_true(len(object_diff(d1, d0)) > 0)

    d1 = deepcopy(d0)
    d1[1] = 2
    assert_true(len(object_diff(d0, d1)) > 0)
    assert_true(len(object_diff(d1, d0)) > 0)
    assert_not_equal(object_hash(d0), object_hash(d1))

    # generators (and other types) not supported
    d1 = deepcopy(d0)
    d2 = deepcopy(d0)
    d1[1] = (x for x in d0)
    d2[1] = (x for x in d0)
    assert_raises(RuntimeError, object_diff, d1, d2)
    assert_raises(RuntimeError, object_hash, d1)

    x = sparse.eye(2, 2, format='csc')
    y = sparse.eye(2, 2, format='csr')
    assert_true('type mismatch' in object_diff(x, y))
    y = sparse.eye(2, 2, format='csc')
    assert_equal(len(object_diff(x, y)), 0)
    y[1, 1] = 2
    assert_true('elements' in object_diff(x, y))
    y = sparse.eye(3, 3, format='csc')
    assert_true('shape' in object_diff(x, y))
    y = 0
    assert_true('type mismatch' in object_diff(x, y))


def test_md5sum():
    """Test md5sum calculation
    """
    tempdir = _TempDir()
    fname1 = op.join(tempdir, 'foo')
    fname2 = op.join(tempdir, 'bar')
    with open(fname1, 'wb') as fid:
        fid.write(b'abcd')
    with open(fname2, 'wb') as fid:
        fid.write(b'efgh')
    assert_equal(md5sum(fname1), md5sum(fname1, 1))
    assert_equal(md5sum(fname2), md5sum(fname2, 1024))
    assert_true(md5sum(fname1) != md5sum(fname2))


def test_tempdir():
    """Test TempDir
    """
    tempdir2 = _TempDir()
    assert_true(op.isdir(tempdir2))
    x = str(tempdir2)
    del tempdir2
    assert_true(not op.isdir(x))


def test_estimate_rank():
    """Test rank estimation
    """
    data = np.eye(10)
    assert_array_equal(estimate_rank(data, return_singular=True)[1],
                       np.ones(10))
    data[0, 0] = 0
    assert_equal(estimate_rank(data), 9)
    assert_raises(ValueError, estimate_rank, data, 'foo')


def test_logging():
    """Test logging (to file)
    """
    assert_raises(ValueError, set_log_level, 'foo')
    tempdir = _TempDir()
    test_name = op.join(tempdir, 'test.log')
    with open(fname_log, 'r') as old_log_file:
        old_lines = clean_lines(old_log_file.readlines())
    with open(fname_log_2, 'r') as old_log_file_2:
        old_lines_2 = clean_lines(old_log_file_2.readlines())

    if op.isfile(test_name):
        os.remove(test_name)
    # test it one way (printing default off)
    set_log_file(test_name)
    set_log_level('WARNING')
    # should NOT print
    evoked = read_evokeds(fname_evoked, condition=1)
    with open(test_name) as fid:
        assert_true(fid.readlines() == [])
    # should NOT print
    evoked = read_evokeds(fname_evoked, condition=1, verbose=False)
    with open(test_name) as fid:
        assert_true(fid.readlines() == [])
    # should NOT print
    evoked = read_evokeds(fname_evoked, condition=1, verbose='WARNING')
    with open(test_name) as fid:
        assert_true(fid.readlines() == [])
    # SHOULD print
    evoked = read_evokeds(fname_evoked, condition=1, verbose=True)
    with open(test_name, 'r') as new_log_file:
        new_lines = clean_lines(new_log_file.readlines())
    assert_equal(new_lines, old_lines)
    set_log_file(None)  # Need to do this to close the old file
    os.remove(test_name)

    # now go the other way (printing default on)
    set_log_file(test_name)
    set_log_level('INFO')
    # should NOT print
    evoked = read_evokeds(fname_evoked, condition=1, verbose='WARNING')
    with open(test_name) as fid:
        assert_true(fid.readlines() == [])
    # should NOT print
    evoked = read_evokeds(fname_evoked, condition=1, verbose=False)
    with open(test_name) as fid:
        assert_true(fid.readlines() == [])
    # SHOULD print
    evoked = read_evokeds(fname_evoked, condition=1)
    with open(test_name, 'r') as new_log_file:
        new_lines = clean_lines(new_log_file.readlines())
    assert_equal(new_lines, old_lines)
    # check to make sure appending works (and as default, raises a warning)
    with warnings.catch_warnings(record=True) as w:
        warnings.simplefilter('always')
        set_log_file(test_name, overwrite=False)
        assert_equal(len(w), 0)
        set_log_file(test_name)
    assert_equal(len(w), 1)
    assert_true('test_utils.py' in w[0].filename)
    evoked = read_evokeds(fname_evoked, condition=1)
    with open(test_name, 'r') as new_log_file:
        new_lines = clean_lines(new_log_file.readlines())
    assert_equal(new_lines, old_lines_2)

    # make sure overwriting works
    set_log_file(test_name, overwrite=True)
    # this line needs to be called to actually do some logging
    evoked = read_evokeds(fname_evoked, condition=1)
    del evoked
    with open(test_name, 'r') as new_log_file:
        new_lines = clean_lines(new_log_file.readlines())
    assert_equal(new_lines, old_lines)


def test_config():
    """Test mne-python config file support"""
    tempdir = _TempDir()
    key = '_MNE_PYTHON_CONFIG_TESTING'
    value = '123456'
    old_val = os.getenv(key, None)
    os.environ[key] = value
    assert_true(get_config(key) == value)
    del os.environ[key]
    # catch the warning about it being a non-standard config key
    assert_true(len(set_config(None, None)) > 10)  # tuple of valid keys
    with warnings.catch_warnings(record=True) as w:
        warnings.simplefilter('always')
        set_config(key, None, home_dir=tempdir, set_env=False)
    assert_true(len(w) == 1)
    assert_true(get_config(key, home_dir=tempdir) is None)
    assert_raises(KeyError, get_config, key, raise_error=True)
    with warnings.catch_warnings(record=True):
        warnings.simplefilter('always')
        assert_true(key not in os.environ)
        set_config(key, value, home_dir=tempdir, set_env=True)
        assert_true(key in os.environ)
        assert_true(get_config(key, home_dir=tempdir) == value)
        set_config(key, None, home_dir=tempdir, set_env=True)
        assert_true(key not in os.environ)
        set_config(key, None, home_dir=tempdir, set_env=True)
        assert_true(key not in os.environ)
    if old_val is not None:
        os.environ[key] = old_val
    # Check if get_config with no input returns all config
    key = 'MNE_PYTHON_TESTING_KEY'
    config = {key: value}
    with warnings.catch_warnings(record=True):  # non-standard key
        warnings.simplefilter('always')
        set_config(key, value, home_dir=tempdir)
    assert_equal(get_config(home_dir=tempdir), config)
    # Check what happens when we use a corrupted file
    json_fname = get_config_path(home_dir=tempdir)
    with open(json_fname, 'w') as fid:
        fid.write('foo{}')
    with warnings.catch_warnings(record=True) as w:
        assert_equal(get_config(home_dir=tempdir), dict())
    assert_true(any('not a valid JSON' in str(ww.message) for ww in w))
    with warnings.catch_warnings(record=True) as w:  # non-standard key
        assert_raises(RuntimeError, set_config, key, 'true', home_dir=tempdir)


@testing.requires_testing_data
def test_show_fiff():
    """Test show_fiff
    """
    # this is not exhaustive, but hopefully bugs will be found in use
    info = show_fiff(fname_evoked)
    keys = ['FIFF_EPOCH', 'FIFFB_HPI_COIL', 'FIFFB_PROJ_ITEM',
            'FIFFB_PROCESSED_DATA', 'FIFFB_EVOKED', 'FIFF_NAVE',
            'FIFF_EPOCH']
    assert_true(all(key in info for key in keys))
    info = show_fiff(fname_raw, read_limit=1024)
    assert_true('COORD_TRANS' in show_fiff(fname_fsaverage_trans))


@deprecated('message')
def deprecated_func():
    pass


@deprecated('message')
class deprecated_class(object):

    def __init__(self):
        pass


def test_deprecated():
    """Test deprecated function
    """
    with warnings.catch_warnings(record=True) as w:
        warnings.simplefilter('always')
        deprecated_func()
    assert_true(len(w) == 1)
    with warnings.catch_warnings(record=True) as w:
        warnings.simplefilter('always')
        deprecated_class()
    assert_true(len(w) == 1)


def _test_fetch(url):
    """Helper to test URL retrieval"""
    tempdir = _TempDir()
    with ArgvSetter(disable_stderr=False):  # to capture stdout
        archive_name = op.join(tempdir, "download_test")
        _fetch_file(url, archive_name, timeout=30., verbose=False,
                    resume=False)
        assert_raises(Exception, _fetch_file, 'NOT_AN_ADDRESS',
                      op.join(tempdir, 'test'), verbose=False)
        resume_name = op.join(tempdir, "download_resume")
        # touch file
        with open(resume_name + '.part', 'w'):
            os.utime(resume_name + '.part', None)
        _fetch_file(url, resume_name, resume=True, timeout=30.,
                    verbose=False)
        assert_raises(ValueError, _fetch_file, url, archive_name,
                      hash_='a', verbose=False)
        assert_raises(RuntimeError, _fetch_file, url, archive_name,
                      hash_='a' * 32, verbose=False)


@requires_good_network
def test_fetch_file_html():
    """Test file downloading over http"""
    _test_fetch('http://google.com')


@requires_ftp
@requires_good_network
def test_fetch_file_ftp():
    """Test file downloading over ftp"""
    _test_fetch('ftp://speedtest.tele2.net/1KB.zip')


def test_sum_squared():
    """Test optimized sum of squares
    """
    X = np.random.RandomState(0).randint(0, 50, (3, 3))
    assert_equal(np.sum(X ** 2), sum_squared(X))


def test_sizeof_fmt():
    """Test sizeof_fmt
    """
    assert_equal(sizeof_fmt(0), '0 bytes')
    assert_equal(sizeof_fmt(1), '1 byte')
    assert_equal(sizeof_fmt(1000), '1000 bytes')


def test_url_to_local_path():
    """Test URL to local path
    """
    assert_equal(_url_to_local_path('http://google.com/home/why.html', '.'),
                 op.join('.', 'home', 'why.html'))


def test_check_type_picks():
    """Test checking type integrity checks of picks
    """
    picks = np.arange(12)
    assert_array_equal(picks, _check_type_picks(picks))
    picks = list(range(12))
    assert_array_equal(np.array(picks), _check_type_picks(picks))
    picks = None
    assert_array_equal(None, _check_type_picks(picks))
    picks = ['a', 'b']
    assert_raises(ValueError, _check_type_picks, picks)
    picks = 'b'
    assert_raises(ValueError, _check_type_picks, picks)


def test_compute_corr():
    """Test Anscombe's Quartett
    """
    x = np.array([10, 8, 13, 9, 11, 14, 6, 4, 12, 7, 5])
    y = np.array([[8.04, 6.95, 7.58, 8.81, 8.33, 9.96,
                   7.24, 4.26, 10.84, 4.82, 5.68],
                  [9.14, 8.14, 8.74, 8.77, 9.26, 8.10,
                   6.13, 3.10, 9.13, 7.26, 4.74],
                  [7.46, 6.77, 12.74, 7.11, 7.81, 8.84,
                   6.08, 5.39, 8.15, 6.42, 5.73],
                  [8, 8, 8, 8, 8, 8, 8, 19, 8, 8, 8],
                  [6.58, 5.76, 7.71, 8.84, 8.47, 7.04,
                   5.25, 12.50, 5.56, 7.91, 6.89]])

    r = compute_corr(x, y.T)
    r2 = np.array([np.corrcoef(x, y[i])[0, 1]
                   for i in range(len(y))])
    assert_allclose(r, r2)
    assert_raises(ValueError, compute_corr, [1, 2], [])


def test_create_slices():
    """Test checking the create of time create_slices
    """
    # Test that create_slices default provide an empty list
    assert_true(create_slices(0, 0) == [])
    # Test that create_slice return correct number of slices
    assert_true(len(create_slices(0, 100)) == 100)
    # Test with non-zero start parameters
    assert_true(len(create_slices(50, 100)) == 50)
    # Test slices' length with non-zero start and window_width=2
    assert_true(len(create_slices(0, 100, length=2)) == 50)
    # Test slices' length with manual slice separation
    assert_true(len(create_slices(0, 100, step=10)) == 10)
    # Test slices' within length for non-consecutive samples
    assert_true(len(create_slices(0, 500, length=50, step=10)) == 46)
    # Test that slices elements start, stop and step correctly
    slices = create_slices(0, 10)
    assert_true(slices[0].start == 0)
    assert_true(slices[0].step == 1)
    assert_true(slices[0].stop == 1)
    assert_true(slices[-1].stop == 10)
    # Same with larger window width
    slices = create_slices(0, 9, length=3)
    assert_true(slices[0].start == 0)
    assert_true(slices[0].step == 1)
    assert_true(slices[0].stop == 3)
    assert_true(slices[-1].stop == 9)
    # Same with manual slices' separation
    slices = create_slices(0, 9, length=3, step=1)
    assert_true(len(slices) == 7)
    assert_true(slices[0].step == 1)
    assert_true(slices[0].stop == 3)
    assert_true(slices[-1].start == 6)
    assert_true(slices[-1].stop == 9)


def test_time_mask():
    """Test safe time masking
    """
    N = 10
    x = np.arange(N).astype(float)
    assert_equal(_time_mask(x, 0, N - 1).sum(), N)
    assert_equal(_time_mask(x - 1e-10, 0, N - 1, sfreq=1000.).sum(), N)
    assert_equal(_time_mask(x - 1e-10, None, N - 1, sfreq=1000.).sum(), N)
    assert_equal(_time_mask(x - 1e-10, None, None, sfreq=1000.).sum(), N)
    assert_equal(_time_mask(x - 1e-10, -np.inf, None, sfreq=1000.).sum(), N)
    assert_equal(_time_mask(x - 1e-10, None, np.inf, sfreq=1000.).sum(), N)
    # non-uniformly spaced inputs
    x = np.array([4, 10])
    assert_equal(_time_mask(x[:1], tmin=10, sfreq=1,
                            raise_error=False).sum(), 0)
    assert_equal(_time_mask(x[:1], tmin=11, tmax=12, sfreq=1,
                            raise_error=False).sum(), 0)
    assert_equal(_time_mask(x, tmin=10, sfreq=1).sum(), 1)
    assert_equal(_time_mask(x, tmin=6, sfreq=1).sum(), 1)
    assert_equal(_time_mask(x, tmin=5, sfreq=1).sum(), 1)
    assert_equal(_time_mask(x, tmin=4.5001, sfreq=1).sum(), 1)
    assert_equal(_time_mask(x, tmin=4.4999, sfreq=1).sum(), 2)
    assert_equal(_time_mask(x, tmin=4, sfreq=1).sum(), 2)
    # degenerate cases
    assert_raises(ValueError, _time_mask, x[:1], tmin=11, tmax=12)
    assert_raises(ValueError, _time_mask, x[:1], tmin=10, sfreq=1)


def test_random_permutation():
    """Test random permutation function
    """
    n_samples = 10
    random_state = 42
    python_randperm = random_permutation(n_samples, random_state)

    # matlab output when we execute rng(42), randperm(10)
    matlab_randperm = np.array([7, 6, 5, 1, 4, 9, 10, 3, 8, 2])

    assert_array_equal(python_randperm, matlab_randperm - 1)


def test_copy_doc():
    '''Test decorator for copying docstrings'''
    class A:
        def m1():
            """Docstring for m1"""
            pass

    class B:
        def m1():
            pass

    class C (A):
        @copy_doc(A.m1)
        def m1():
            pass

    assert_equal(C.m1.__doc__, 'Docstring for m1')
    assert_raises(ValueError, copy_doc(B.m1), C.m1)


def test_copy_function_doc_to_method_doc():
    '''Test decorator for re-using function docstring as method docstrings'''
    def f1(object, a, b, c):
        """Docstring for f1

        Parameters
        ----------
        object : object
            Some object. This description also has

            blank lines in it.
        a : int
            Parameter a
        b : int
            Parameter b
        """
        pass

    def f2(object):
        """Docstring for f2

        Parameters
        ----------
        object : object
            Only one parameter

        Returns
        -------
        nothing.
        """
        pass

    def f3(object):
        """Docstring for f3

        Parameters
        ----------
        object : object
            Only one parameter
        """
        pass

    def f4(object):
        """Docstring for f4"""
        pass

    def f5(object):
        """Docstring for f5

        Parameters
        ----------
        Returns
        -------
        nothing.
        """
        pass

    class A:
        @copy_function_doc_to_method_doc(f1)
        def method_f1(self, a, b, c):
            pass

        @copy_function_doc_to_method_doc(f2)
        def method_f2(self):
            "method_f3 own docstring"
            pass

        @copy_function_doc_to_method_doc(f3)
        def method_f3(self):
            pass

    assert_equal(
        A.method_f1.__doc__,
        """Docstring for f1

        Parameters
        ----------
        a : int
            Parameter a
        b : int
            Parameter b
        """
    )

    assert_equal(
        A.method_f2.__doc__,
        """Docstring for f2

        Returns
        -------
        nothing.
        method_f3 own docstring"""
    )

    assert_equal(A.method_f3.__doc__, 'Docstring for f3\n\n        ')
    assert_raises(ValueError, copy_function_doc_to_method_doc(f4), A.method_f1)
    assert_raises(ValueError, copy_function_doc_to_method_doc(f5), A.method_f1)

run_tests_if_main()