import pytest

import matplotlib.colors as mcolors

from matplotlib.lines import _get_dash_pattern

from matplotlib._style_helpers import style_generator

@pytest.mark.parametrize('key, value', [('facecolor', ["b", "g", "r"]),

('edgecolor', ["b", "g", "r"]),

('hatch', ["/", "\\", "."]),

('linestyle', ["-", "--", ":"]),

('linewidth', [1, 1.5, 2])])

def test_style_generator_list(key, value):

"""Test that style parameter lists are distributed to the generator."""

kw = {'foo': 12, key: value}

new_kw, gen = style_generator(kw)

assert new_kw == {'foo': 12}

for v in value * 2: # Result should repeat

style_dict = next(gen)

assert len(style_dict) == 1

if key.endswith('color'):

assert mcolors.same_color(v, style_dict[key])

elif key == 'linestyle':

assert _get_dash_pattern(v) == style_dict[key]

else:

assert v == style_dict[key]

@pytest.mark.parametrize('key, value', [('facecolor', "b"),

('edgecolor', "b"),

('hatch', "/"),

('linestyle', "-"),

('linewidth', 1)])

def test_style_generator_single(key, value):

"""Test that single-value style parameters are distributed to the generator."""

kw = {'foo': 12, key: value}

new_kw, gen = style_generator(kw)

assert new_kw == {'foo': 12}

for _ in range(2): # Result should repeat

style_dict = next(gen)

if key.endswith('color'):

assert mcolors.same_color(value, style_dict[key])

elif key == 'linestyle':

assert _get_dash_pattern(value) == style_dict[key]

else:

assert value == style_dict[key]

@pytest.mark.parametrize('key', ['facecolor', 'hatch', 'linestyle'])

def test_style_generator_raises_on_empty_style_parameter_list(key):

kw = {key: []}

with pytest.raises(TypeError, match=f'{key} must not be an empty sequence'):

style_generator(kw)

def test_style_generator_sequence_type_styles():

"""

Test that sequence type style values are detected as single value

and passed to all elements of the generator.

"""

kw = {'facecolor': ('r', 0.5),

'edgecolor': [0.5, 0.5, 0.5],

'linestyle': (0, (1, 1))}

_, gen = style_generator(kw)

for _ in range(2): # Result should repeat

style_dict = next(gen)

mcolors.same_color(kw['facecolor'], style_dict['facecolor'])

mcolors.same_color(kw['edgecolor'], style_dict['edgecolor'])

kw['linestyle'] == style_dict['linestyle']

def test_style_generator_none():

kw = {'facecolor': 'none',

'edgecolor': 'none'}

_, gen = style_generator(kw)

for _ in range(2): # Result should repeat

style_dict = next(gen)

assert style_dict['facecolor'] == 'none'

assert style_dict['edgecolor'] == 'none'