def mixin_exists(namespace, name):
expect_type(name, String)
# TODO invasive, but there's no other way to ask for this at the moment
for fname, arity in namespace._mixins.keys():
if name.value == fname:
return Boolean(True)
return Boolean(False)
def mixin_exists(namespace, name):
expect_type(name, String)
# TODO invasive, but there's no other way to ask for this at the moment
for fname, arity in namespace._mixins.keys():
if name.value == fname:
return Boolean(True)
return Boolean(False)
def change_color(color, red=None, green=None, blue=None, hue=None, saturation=None, lightness=None, alpha=None):
do_rgb = red or green or blue
do_hsl = hue or saturation or lightness
if do_rgb and do_hsl:
raise ValueError("Can't change both RGB and HSL channels at the same time")
if alpha is None:
alpha = color.alpha
else:
alpha = alpha.value
if do_rgb:
channels = list(color.rgba[:3])
if red:
channels[0] = _interpret_percentage(red, relto=255)
if green:
channels[1] = _interpret_percentage(green, relto=255)
if blue:
channels[2] = _interpret_percentage(blue, relto=255)
return Color.from_rgb(*channels, alpha=alpha)
else:
channels = list(color.hsl)
if hue:
expect_type(hue, Number, unit=None)
channels[0] = (hue.value / 360) % 1
# Ruby sass treats plain numbers for saturation and lightness as though
# they were percentages, just without the %
if saturation:
channels[1] = _interpret_percentage(saturation, relto=100)
if lightness:
channels[2] = _interpret_percentage(lightness, relto=100)
return Color.from_hsl(*channels, alpha=alpha)
def change_color(color, red=None, green=None, blue=None, hue=None, saturation=None, lightness=None, alpha=None):
do_rgb = red or green or blue
do_hsl = hue or saturation or lightness
if do_rgb and do_hsl:
raise ValueError("Can't change both RGB and HSL channels at the same time")
if alpha is None:
alpha = color.alpha
else:
alpha = alpha.value
if do_rgb:
channels = list(color.rgba[:3])
if red:
channels[0] = _interpret_percentage(red, relto=255)
if green:
channels[1] = _interpret_percentage(green, relto=255)
if blue:
channels[2] = _interpret_percentage(blue, relto=255)
return Color.from_rgb(*channels, alpha=alpha)
else:
channels = list(color.hsl)
if hue:
expect_type(hue, Number, unit=None)
channels[0] = (hue.value / 360) % 1
# Ruby sass treats plain numbers for saturation and lightness as though
# they were percentages, just without the %
if saturation:
channels[1] = _interpret_percentage(saturation, relto=100)
if lightness:
channels[2] = _interpret_percentage(lightness, relto=100)
return Color.from_hsl(*channels, alpha=alpha)
def set_nth(list, n, value):
expect_type(n, Number, unit=None)
py_n = n.to_python_index(len(list))
return List(
tuple(list[:py_n]) + (value,) + tuple(list[py_n + 1:]),
use_comma=list.use_comma)
def join(lst1, lst2, separator=String.unquoted('auto')):
expect_type(separator, String)
ret = []
ret.extend(List.from_maybe(lst1))
ret.extend(List.from_maybe(lst2))
if separator.value == 'comma':
use_comma = True
elif separator.value == 'space':
use_comma = False
elif separator.value == 'auto':
# The Sass docs are slightly misleading here, but the algorithm is: use
# the delimiter from the first list that has at least 2 items, or
# default to spaces.
if len(lst1) > 1:
use_comma = lst1.use_comma
elif len(lst2) > 1:
use_comma = lst2.use_comma
else:
use_comma = False
else:
raise ValueError("separator for join() must be comma, space, or auto")
return List(ret, use_comma=use_comma)
def set_nth(list, n, value):
expect_type(n, Number, unit=None)
py_n = n.to_python_index(len(list))
return List(
tuple(list[:py_n]) + (value,) + tuple(list[py_n + 1:]),
use_comma=list.use_comma)
def join(lst1, lst2, separator=String.unquoted('auto')):
expect_type(separator, String)
ret = []
ret.extend(List.from_maybe(lst1))
ret.extend(List.from_maybe(lst2))
if separator.value == 'comma':
use_comma = True
elif separator.value == 'space':
use_comma = False
elif separator.value == 'auto':
# The Sass docs are slightly misleading here, but the algorithm is: use
# the delimiter from the first list that has at least 2 items, or
# default to spaces.
if len(lst1) > 1:
use_comma = lst1.use_comma
elif len(lst2) > 1:
use_comma = lst2.use_comma
else:
use_comma = False
else:
raise ValueError("separator for join() must be comma, space, or auto")
return List(ret, use_comma=use_comma)
def absolute_path(relative_path):
"""Return an absolute path for the given relative path, relative to the
calling file.
"""
expect_type(relative_path, String)
# TODO i can't get the calling file until "rule" or something else helpful
# is actually passed in!
return String(os.path.abspath(relative_path.value))
def variable_exists(namespace, name):
expect_type(name, String)
try:
namespace.variable('$' + name.value)
except KeyError:
return Boolean(False)
else:
return Boolean(True)
def absolute_path(relative_path):
"""Return an absolute path for the given relative path, relative to the
calling file.
"""
expect_type(relative_path, String)
# TODO i can't get the calling file until "rule" or something else helpful
# is actually passed in!
return String(os.path.abspath(relative_path.value))
def variable_exists(namespace, name):
expect_type(name, String)
try:
namespace.variable('$' + name.value)
except KeyError:
return Boolean(False)
else:
return Boolean(True)
def invert(color):
"""Returns the inverse (negative) of a color. The red, green, and blue
values are inverted, while the opacity is left alone.
"""
if isinstance(color, Number):
# invert(n) and invert(n%) are CSS3 filters and should be left
# intact
return String.unquoted("invert(%s)" % (color.render(), ))
expect_type(color, Color)
r, g, b, a = color.rgba
return Color.from_rgb(1 - r, 1 - g, 1 - b, alpha=a)
def invert(color):
"""Returns the inverse (negative) of a color. The red, green, and blue
values are inverted, while the opacity is left alone.
"""
if isinstance(color, Number):
# invert(n) and invert(n%) are CSS3 filters and should be left
# intact
return String.unquoted("invert(%s)" % (color.render(),))
expect_type(color, Color)
r, g, b, a = color.rgba
return Color.from_rgb(1 - r, 1 - g, 1 - b, alpha=a)
def join_file_segments(*segments):
"""Join path parts into a single path, using the appropriate OS-specific
delimiter.
"""
parts = []
for segment in segments:
expect_type(segment, String)
parts.append(segment.value)
if parts:
return String(os.path.join(*parts))
else:
return String('')
def join_file_segments(*segments):
"""Join path parts into a single path, using the appropriate OS-specific
delimiter.
"""
parts = []
for segment in segments:
expect_type(segment, String)
parts.append(segment.value)
if parts:
return String(os.path.join(*parts))
else:
return String('')
def global_variable_exists(namespace, name):
expect_type(name, String)
# TODO this is... imperfect and invasive, but should be a good
# approximation
scope = namespace._variables
while len(scope.maps) > 1:
scope = scope.maps[-1]
try:
scope['$' + name.value]
except KeyError:
return Boolean(False)
else:
return Boolean(True)
def global_variable_exists(namespace, name):
expect_type(name, String)
# TODO this is... imperfect and invasive, but should be a good
# approximation
scope = namespace._variables
while len(scope.maps) > 1:
scope = scope.maps[-1]
try:
scope['$' + name.value]
except KeyError:
return Boolean(False)
else:
return Boolean(True)
def _interpret_percentage(n, relto=1., clamp=True):
expect_type(n, Number, unit='%')
if n.is_unitless:
ret = n.value / relto
else:
ret = n.value / 100
if clamp:
if ret < 0:
return 0
elif ret > 1:
return 1
return ret
def _interpret_percentage(n, relto=1., clamp=True):
expect_type(n, Number, unit='%')
if n.is_unitless:
ret = n.value / relto
else:
ret = n.value / 100
if clamp:
if ret < 0:
return 0
elif ret > 1:
return 1
return ret
def nth(lst, n):
"""Return the nth item in the list."""
expect_type(n, (String, Number), unit=None)
if isinstance(n, String):
if n.value.lower() == 'first':
i = 0
elif n.value.lower() == 'last':
i = -1
else:
raise ValueError("Invalid index %r" % (n,))
else:
# DEVIATION: nth treats lists as circular lists
i = n.to_python_index(len(lst), circular=True)
return lst[i]
def _scale_channel(channel, scaleby):
if scaleby is None:
return channel
expect_type(scaleby, Number)
if not scaleby.is_simple_unit('%'):
raise ValueError("Expected percentage, got %r" % (scaleby,))
factor = scaleby.value / 100
if factor > 0:
# Add x% of the remaining range, up to 1
return channel + (1 - channel) * factor
else:
# Subtract x% of the existing channel. We add here because the factor
# is already negative
return channel * (1 + factor)
def _scale_channel(channel, scaleby):
if scaleby is None:
return channel
expect_type(scaleby, Number)
if not scaleby.is_simple_unit('%'):
raise ValueError("Expected percentage, got %r" % (scaleby,))
factor = scaleby.value / 100
if factor > 0:
# Add x% of the remaining range, up to 1
return channel + (1 - channel) * factor
else:
# Subtract x% of the existing channel. We add here because the factor
# is already negative
return channel * (1 + factor)
def nth(lst, n):
"""Return the nth item in the list."""
expect_type(n, (String, Number), unit=None)
if isinstance(n, String):
if n.value.lower() == 'first':
i = 0
elif n.value.lower() == 'last':
i = -1
else:
raise ValueError("Invalid index %r" % (n,))
else:
# DEVIATION: nth treats lists as circular lists
i = n.to_python_index(len(lst), circular=True)
return lst[i]
def nth(lst, n):
"""
Return the Nth item in the string
"""
expect_type(n, (String, Number), unit=None)
if isinstance(n, String):
if n.value.lower() == "first":
i = 0
elif n.value.lower() == "last":
i = -1
else:
raise ValueError("Invalid index %r" % (n,))
else:
i = (int(n.value) - 1) % len(lst)
return lst[i]
def append(lst, val, separator=String.unquoted('auto')):
expect_type(separator, String)
ret = []
ret.extend(List.from_maybe(lst))
ret.append(val)
separator = separator.value
if separator == 'comma':
use_comma = True
elif separator == 'space':
use_comma = False
elif separator == 'auto':
if len(lst) < 2:
use_comma = False
else:
use_comma = lst.use_comma
else:
raise ValueError('Separator must be auto, comma, or space')
return List(ret, use_comma=use_comma)
def append(lst, val, separator=String.unquoted('auto')):
expect_type(separator, String)
ret = []
ret.extend(List.from_maybe(lst))
ret.append(val)
separator = separator.value
if separator == 'comma':
use_comma = True
elif separator == 'space':
use_comma = False
elif separator == 'auto':
if len(lst) < 2:
use_comma = False
else:
use_comma = lst.use_comma
else:
raise ValueError('Separator must be auto, comma, or space')
return List(ret, use_comma=use_comma)
def str_insert(string, insert, index):
expect_type(string, String)
expect_type(insert, String)
expect_type(index, Number, unit=None)
py_index = index.to_python_index(len(string.value), check_bounds=False)
return String(string.value[:py_index] + insert.value + string.value[py_index:], quotes=string.quotes)
def str_insert(string, insert, index):
expect_type(string, String)
expect_type(insert, String)
expect_type(index, Number, unit=None)
py_index = index.to_python_index(len(string.value), check_bounds=False)
return String(
string.value[:py_index] + insert.value + string.value[py_index:],
quotes=string.quotes)
def str_slice(string, start_at, end_at=None):
expect_type(string, String)
expect_type(start_at, Number, unit=None)
py_start_at = start_at.to_python_index(len(string.value))
if end_at is None:
py_end_at = None
else:
expect_type(end_at, Number, unit=None)
# Endpoint is inclusive, unlike Python
py_end_at = end_at.to_python_index(len(string.value)) + 1
return String(string.value[py_start_at:py_end_at], quotes=string.quotes)
def str_slice(string, start_at, end_at=None):
expect_type(string, String)
expect_type(start_at, Number, unit=None)
py_start_at = start_at.to_python_index(len(string.value))
if end_at is None:
py_end_at = None
else:
expect_type(end_at, Number, unit=None)
# Endpoint is inclusive, unlike Python
py_end_at = end_at.to_python_index(len(string.value)) + 1
return String(
string.value[py_start_at:py_end_at],
quotes=string.quotes)
def str_length(string):
expect_type(string, String)
# nb: can't use `len(string)`, because that gives the Sass list length,
# which is 1
return Number(len(string.value))
def keywords(value):
"""Extract named arguments, as a map, from an argument list."""
expect_type(value, Arglist)
return value.extract_keywords()
def split_filename(path):
expect_type(path, String)
dir_, file_ = os.path.split(path.value)
base, ext = os.path.splitext(file_)
return List([String(dir_), String(base), String(ext)], use_comma=False)
def split_filename(path):
expect_type(path, String)
dir_, file_ = os.path.split(path.value)
base, ext = os.path.splitext(file_)
return List([String(dir_), String(base), String(ext)], use_comma=False)
def str_index(string, substring):
expect_type(string, String)
expect_type(substring, String)
# 1-based indexing, with 0 for failure
return Number(string.value.find(substring.value) + 1)
def percentage(value):
expect_type(value, Number, unit=None)
return value * Number(100, unit='%')
def to_lower_case(string):
expect_type(string, String)
return String(string.value.lower(), quotes=string.quotes)
def str_index(string, substring):
expect_type(string, String)
expect_type(substring, String)
# 1-based indexing, with 0 for failure
return Number(string.value.find(substring.value) + 1)
def str_length(string):
expect_type(string, String)
# nb: can't use `len(string)`, because that gives the Sass list length,
# which is 1
return Number(len(string.value))
def to_lower_case(string):
expect_type(string, String)
return String(string.value.lower(), quotes=string.quotes)
def percentage(value):
expect_type(value, Number, unit=None)
return value * Number(100, unit='%')
def keywords(value):
"""Extract named arguments, as a map, from an argument list."""
expect_type(value, Arglist)
return value.extract_keywords()
