Added functions for converting colors

color.py

@@ -0,0 +1,63 @@
+import re
+
+
+NAME_TO_HEX = {
+        'aqua': '#0ff',
+        'black': '#000',
+        'blue': '#00f',
+        'fuchsia': '#f0f',
+        'lime': '#0f0',
+        'white': '#fff',
+        'yellow': '#ff0'
+        }
+
+
+HEX_TO_NAME = {
+        '#808080': 'gray',
+        '#008000': 'green',
+        '#800000': 'maroon',
+        '#000080': 'navy',
+        '#8080000': 'olive',
+        '#800080': 'purple',
+        '#f00': 'red',
+        '#c0c0c0': 'silver',
+        '#008080': 'teal'
+        }
+
+
+def _rgb_to_hex(rgb):
+    return '#%02x%02x%02x' % rgb
+
+
+def color_shortcut(color):
+    color = color.lower()
+
+    # 'grey' and 'gray' are synonyms im most browsers, use 'gray' for correct
+    # behaviour in IE
+    if color == 'grey':
+        color = 'gray'
+
+    # Try converting RGB to hexadecimal, which is always shorter
+    rgb = re.search(r'^rgb\((\d{1,3}), (\d{1,3}), (\d{1,3})\)$', color)
+
+    if rgb:
+        color = _rgb_to_hex(map(int, rgb.groups()))
+
+    # Check if hexadecimal code
+    hexa = re.search(r'^#([a-z0-9]{6})$', color)
+
+    if hexa:
+        code = hexa.group(1)
+
+        # Check if a 3-character variant is possible, e.g. 11ff00 -> 1f0
+        if code[0] == code[1] and code[2] == code[3] and code[4] == code[5]:
+            color = '#' + code[0] + code[2] + code[4]
+
+        # Try to replace long hexadecimals with shorter color names
+        if color in HEX_TO_NAME:
+            return HEX_TO_NAME[color]
+    elif color in NAME_TO_HEX:
+        # Long color names can be replaced with shorted hexadecimal codes
+        return NAME_TO_HEX[color]
+
+    return color

tests/test_color.py

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+from unittest import TestCase
+
+from color import _rgb_to_hex, color_shortcut
+
+
+class TestColor(TestCase):
+    def test__rgb_to_hex(self):
+        pass
+
+    def test_color_shortcut(self):
+        pass