More efficient memory layout for Line

kitty_tests/__init__.py

@@ -13,8 +13,7 @@ class BaseTest(TestCase):
 def set_text_in_line(line, text, offset=0):
     pos = offset
     for ch in text:
-        line.char[pos] = ord(ch)
-        line.width[pos] = 1
+        line.set_char(pos, ch)
         pos += 1
         if pos >= len(line):
             break

kitty_tests/datatypes.py

@@ -61,3 +61,14 @@ class TestDataTypes(BaseTest):
         l = lo.copy()
         l.left_shift(7, 3)
         self.ae(str(l), t)
+
+        l = Line(1)
+        l.set_decoration(0, 2)
+        q = Cursor()
+        for x in 'bold italic reverse strikethrough'.split():
+            getattr(l, 'set_' + x)(0, True)
+            setattr(q, x, True)
+        q.decoration = 2
+        l.set_decoration(0, q.decoration)
+        c = l.cursor_from(0)
+        self.ae(c, q)