Use a set to represent supported character codes

tests/test_chars.py

@@ -1,6 +1,7 @@
 import unittest
 
 from vesta.chars import CHARCODES
+from vesta.chars import CHARMAP
 from vesta.chars import COLS
 from vesta.chars import ROWS
 from vesta.chars import Color
@@ -11,11 +12,11 @@
 
 class EncodeTests(unittest.TestCase):
     def test_printable_characters(self):
-        for c in CHARCODES:
+        for c in CHARMAP:
             encode(c)
 
     def test_character_codes(self):
-        for i in range(0, 70):
+        for i in CHARCODES:
             encode(f"{{{i}}}")
 
     def test_bad_characters(self):

vesta/chars.py

@@ -12,7 +12,7 @@
 ROWS = 6
 COLS = 22
 PRINTABLE = " ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890!@#$() - +&=;: '\"%,.  /? °"
-CHARCODES = {c: idx for idx, c in enumerate(PRINTABLE) if idx == 0 or c != " "}
+CHARMAP = {c: idx for idx, c in enumerate(PRINTABLE) if idx == 0 or c != " "}
 
 
 class Color(enum.IntEnum):
@@ -38,6 +38,10 @@ def __new__(cls, value: int, ansi: str):
     # fmt: on
 
 
+#: The set of all supported character codes.
+CHARCODES = frozenset(CHARMAP.values()).union(Color)
+
+
 def encode(s: str) -> List[int]:
     """Encodes a string as a list of character codes.
 
@@ -65,11 +69,11 @@ def encode(s: str) -> List[int]:
                 skip_to = i + 4
             else:
                 raise ValueError(f"{i+1}: missing }} at index {i+2} or {i+3}")
-            if not (0 <= out[-1] <= 69):
+            if out[-1] not in CHARCODES:
                 raise ValueError(f"{i+2}: unsupported character code: {out[-1]}")
         else:
             try:
-                out.append(CHARCODES[c])
+                out.append(CHARMAP[c])
             except KeyError:
                 raise ValueError(f"{i+1}: unsupported character: {c}")