PR: Add font properties handling

.github/workflows/ci.yml

@@ -30,6 +30,10 @@ jobs:
  runs-on: ubuntu-latest
  steps:
  - uses: actions/checkout@v1
+ - name: Copy Ahem font
+ run: |
+ mkdir -p ~/.local/share/fonts/
+ cp tests/fonts/ahem.ttf ~/.local/share/fonts/ahem.ttf
  - name: Set up Python 3.7
  uses: actions/setup-python@v1
  with:
@@ -52,6 +56,10 @@ jobs:
  python-version: [3.5, 3.6]
  steps:
  - uses: actions/checkout@v1
+ - name: Copy Ahem font
+ run: |
+ mkdir -p ~/.local/share/fonts/
+ cp tests/fonts/ahem.ttf ~/.local/share/fonts/ahem.ttf
  - name: Set up Python ${{ matrix.python-version }}
  uses: actions/setup-python@v1
  with:

colosseum/constants.py

@@ -1,5 +1,9 @@
-from .validators import (is_color, is_integer, is_length, is_number,
- is_percentage, ValidationError)
+import os
+import sys
+
+from .validators import (ValidationError, is_color, is_font_family,
+ is_integer, is_length,
+ is_number, is_percentage)
 
 
 class Choices:
@@ -34,15 +38,15 @@ def validate(self, value):
  raise ValueError()
 
  def __str__(self):
- choices = set([str(c).lower().replace('_', '-') for c in self.constants])
+ choices = [str(c).lower().replace('_', '-') for c in self.constants]
  for validator in self.validators:
- choices.add(validator.description)
+ choices += validator.description.split(', ')
 
  if self.explicit_defaulting_constants:
  for item in self.explicit_defaulting_constants:
- choices.add(item)
+ choices.append(item)
 
- return ", ".join(sorted(choices))
+ return ", ".join(sorted(set(choices)))
 
 
 ######################################################################
@@ -235,6 +239,8 @@ def __str__(self):
 # 10.8 Leading and half-leading
 ######################################################################
 # line_height
+LINE_HEIGHT_CHOICES = Choices(NORMAL, validators=[is_number, is_length, is_percentage],
+ explicit_defaulting_constants=[INHERIT])
 # vertical_align
 
 ######################################################################
@@ -317,26 +323,174 @@ def __str__(self):
 ######################################################################
 # font_family
 
+SERIF = 'serif'
+SANS_SERIF = 'sans-serif'
+CURSIVE = 'cursive'
+FANTASY = 'fantasy'
+MONOSPACE = 'monospace'
+
+GENERIC_FAMILY_FONTS = [SERIF, SANS_SERIF, CURSIVE, FANTASY, MONOSPACE]
+
+
+def available_font_families():
+ """List available font family names."""
+ if sys.platform == 'darwin':
+ return _available_font_families_mac()
+ elif sys.platform.startswith('linux'):
+ return _available_font_families_unix()
+ elif os.name == 'nt':
+ return _available_font_families_win()
+
+ return []
+
+
+def _available_font_families_mac():
+ """List available font family names on mac."""
+ from ctypes import cdll, util
+ from rubicon.objc import ObjCClass
+ appkit = cdll.LoadLibrary(util.find_library('AppKit')) # noqa
+ NSFontManager = ObjCClass("NSFontManager")
+ NSFontManager.declare_class_property('sharedFontManager')
+ NSFontManager.declare_class_property("sharedFontManager")
+ NSFontManager.declare_property("availableFontFamilies")
+ manager = NSFontManager.sharedFontManager
+ return list(sorted(str(item) for item in manager.availableFontFamilies if item))
+
+
+def _available_font_families_unix():
+ """List available font family names on unix."""
+ import subprocess
+ p = subprocess.check_output(['fc-list', ':', 'family'])
+ fonts = p.decode().split('\n')
+ return list(sorted(set(item for item in fonts if item)))
+
+
+def _available_font_families_win():
+ """List available font family names on windows."""
+ import winreg
+ key = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE,
+ r"Software\Microsoft\Windows NT\CurrentVersion\Fonts",
+ 0,
+ winreg.KEY_READ)
+ fonts = set()
+ for idx in range(0, winreg.QueryInfoKey(key)[1]):
+ font_name = winreg.EnumValue(key, idx)[0]
+ font_name = font_name.replace(' (TrueType)', '')
+ fonts.add(font_name)
+ return list(sorted(fonts))
+
+
+AVAILABLE_FONT_FAMILIES = available_font_families()
+FONT_FAMILY_CHOICES = Choices(
+ validators=[is_font_family(generic_family=GENERIC_FAMILY_FONTS, font_families=AVAILABLE_FONT_FAMILIES)],
+ explicit_defaulting_constants=[INHERIT, INITIAL],
+)
+
 ######################################################################
 # 15.4 Font Styling
 ######################################################################
 # font_style
+NORMAL = 'normal'
+ITALIC = 'italic'
+OBLIQUE = 'oblique'
+
+FONT_STYLE_CHOICES = Choices(
+ NORMAL,
+ ITALIC,
+ OBLIQUE,
+ explicit_defaulting_constants=[INHERIT],
+)
 
 ######################################################################
 # 15.5 Small-caps
 ######################################################################
 # font_variant
+SMALL_CAPS = 'small-caps'
+FONT_VARIANT_CHOICES = Choices(
+ NORMAL,
+ SMALL_CAPS,
+ explicit_defaulting_constants=[INHERIT],
+)
 
 ######################################################################
 # 15.6 Font boldness
 ######################################################################
 # font_weight
+BOLD = 'bold'
+BOLDER = 'bolder'
+LIGHTER = 'lighter'
+
+FONT_WEIGHT_CHOICES = Choices(
+ NORMAL,
+ BOLD,
+ BOLDER,
+ LIGHTER,
+ 100,
+ 200,
+ 300,
+ 400,
+ 500,
+ 600,
+ 700,
+ 800,
+ 900,
+ explicit_defaulting_constants=[INHERIT],
+)
 
 ######################################################################
 # 15.7 Font size
 ######################################################################
 # font_size
 
+# <absolute-size>
+XX_SMALL = 'xx-small'
+X_SMALL = 'x-small'
+SMALL = 'small'
+MEDIUM = 'medium'
+LARGE = 'large'
+X_LARGE = 'x-large'
+XX_LARGE = 'xx-large'
+
+# <relative-size>
+LARGER = 'larger'
+SMALLER = 'smaller'
+
+FONT_SIZE_CHOICES = Choices(
+ XX_SMALL,
+ X_SMALL,
+ SMALL,
+ MEDIUM,
+ LARGE,
+ X_LARGE,
+ XX_LARGE,
+ LARGER,
+ SMALLER,
+ validators=[is_length, is_percentage],
+ explicit_defaulting_constants=[INHERIT],
+)
+
+######################################################################
+# 15.8 Font shorthand
+######################################################################
+
+ICON = 'icon'
+CAPTION = 'caption'
+MENU = 'menu'
+MESSAGE_BOX = 'message-box'
+SMALL_CAPTION = 'small-caption'
+STATUS_BAR = 'status-bar'
+
+SYSTEM_FONT_KEYWORDS = [ICON, CAPTION, MENU, MESSAGE_BOX, SMALL_CAPTION, STATUS_BAR]
+
+INITIAL_FONT_VALUES = {
+ 'font_style': NORMAL,
+ 'font_variant': NORMAL,
+ 'font_weight': NORMAL,
+ 'font_size': MEDIUM,
+ 'line_height': NORMAL,
+ 'font_family': [INITIAL], # TODO: Depends on user agent. What to use?
+}
+
 ######################################################################
 # 16. Text ###########################################################
 ######################################################################

colosseum/declaration.py

@@ -12,22 +12,80 @@
  MIN_SIZE_CHOICES, NORMAL, NOWRAP, ORDER_CHOICES, PADDING_CHOICES,
  POSITION_CHOICES, ROW, SIZE_CHOICES, STATIC, STRETCH,
  TRANSPARENT, UNICODE_BIDI_CHOICES, VISIBILITY_CHOICES, VISIBLE,
- Z_INDEX_CHOICES, default,
+ Z_INDEX_CHOICES, default, FONT_STYLE_CHOICES, FONT_VARIANT_CHOICES,
+ FONT_WEIGHT_CHOICES, FONT_SIZE_CHOICES, MEDIUM, FONT_FAMILY_CHOICES, INITIAL,
+ INITIAL_FONT_VALUES, LINE_HEIGHT_CHOICES,
 )
+from .fonts import construct_font_property, parse_font_property
+
 
 _CSS_PROPERTIES = set()
 
 
-def unvalidated_property(name, choices, initial):
- "Define a simple CSS property attribute."
- initial = choices.validate(initial)
+def validated_font_property(name, initial):
+ """Define the shorthand CSS font property."""
+ assert isinstance(initial, dict)
+ initial = initial.copy()
 
  def getter(self):
- return getattr(self, '_%s' % name, initial)
+ font = initial
+ for property_name in font:
+ font[property_name] = getattr(self, property_name)
+ return getattr(self, '_%s' % name, construct_font_property(font))
 
  def setter(self, value):
- if value != getattr(self, '_%s' % name, initial):
- setattr(self, '_%s' % name, value)
+ font = parse_font_property(value)
+ for property_name, property_value in font.items():
+ setattr(self, property_name, property_value)
+ self.dirty = True
+ setattr(self, '_%s' % name, value)
+
+ def deleter(self):
+ try:
+ delattr(self, '_%s' % name)
+ self.dirty = True
+ except AttributeError:
+ # Attribute doesn't exist
+ pass
+
+ for property_name in INITIAL_FONT_VALUES:
+ try:
+ delattr(self, property_name)
+ self.dirty = True
+ except AttributeError:
+ # Attribute doesn't exist
+ pass
+
+ _CSS_PROPERTIES.add(name)
+ return property(getter, setter, deleter)
+
+
+def validated_list_property(name, choices, initial, separator=','):
+ """Define a property holding a list values."""
+ if not isinstance(initial, list):
+ raise ValueError('Initial value must be a list!')
+
+ def getter(self):
+ # TODO: A copy is returned so if the user mutates it,
+ # it will not affect the stored value
+ return getattr(self, '_%s' % name, initial)[:]
+
+ def setter(self, value):
+ try:
+ if not isinstance(value, str):
+ value = separator.join(value)
+
+ # This should be a list of values
+ values = choices.validate(value)
+ if not isinstance(values, list):
+ values.split(separator)
+ except ValueError:
+ raise ValueError("Invalid value '%s' for CSS property '%s'; Valid values are: %s" % (
+ value, name, choices
+ ))
+
+ if values != getattr(self, '_%s' % name, initial):
+ setattr(self, '_%s' % name, values[:])
  self.dirty = True
 
  def deleter(self):
@@ -127,6 +185,30 @@ def deleter(self):
  return property(getter, setter, deleter)
 
 
+def unvalidated_property(name, choices, initial):
+ "Define a simple CSS property attribute."
+ initial = choices.validate(initial)
+
+ def getter(self):
+ return getattr(self, '_%s' % name, initial)
+
+ def setter(self, value):
+ if value != getattr(self, '_%s' % name, initial):
+ setattr(self, '_%s' % name, value)
+ self.dirty = True
+
+ def deleter(self):
+ try:
+ delattr(self, '_%s' % name)
+ self.dirty = True
+ except AttributeError:
+ # Attribute doesn't exist
+ pass
+
+ _CSS_PROPERTIES.add(name)
+ return property(getter, setter, deleter)
+
+
 class CSS:
  def __init__(self, **style):
  self._node = None
@@ -222,7 +304,7 @@ def __init__(self, **style):
  max_height = validated_property('max_height', choices=MAX_SIZE_CHOICES, initial=None)
 
  # 10.8 Leading and half-leading
- # line_height
+ line_height = validated_property('line_height', choices=LINE_HEIGHT_CHOICES, initial=NORMAL)
  # vertical_align
 
  # 11. Visual effects #################################################
@@ -276,22 +358,22 @@ def __init__(self, **style):
 
  # 15. Fonts ##########################################################
  # 15.3 Font family
- # font_family
+ font_family = validated_list_property('font_family', choices=FONT_FAMILY_CHOICES, initial=[INITIAL])
 
  # 15.4 Font Styling
- # font_style
+ font_style = validated_property('font_style', choices=FONT_STYLE_CHOICES, initial=NORMAL)
 
  # 15.5 Small-caps
- # font_variant
+ font_variant = validated_property('font_variant', choices=FONT_VARIANT_CHOICES, initial=NORMAL)
 
  # 15.6 Font boldness
- # font_weight
+ font_weight = validated_property('font_weight', choices=FONT_WEIGHT_CHOICES, initial=NORMAL)
 
  # 15.7 Font size
- # font_size
+ font_size = validated_property('font_size', choices=FONT_SIZE_CHOICES, initial=MEDIUM)
 
  # 15.8 Shorthand font property
- # font
+ font = validated_font_property('font', initial=INITIAL_FONT_VALUES)
 
  # 16. Text ###########################################################
  # 16.1 Indentation