Move color type aliases into wv_colors.py to avoid circular imports

src/wireviz/DataClasses.py

@@ -6,7 +6,7 @@
 from pathlib import Path
 
 from wireviz.wv_helper import int2tuple, aspect_ratio
-from wireviz import wv_colors
+from wireviz.wv_colors import Color, Colors, ColorMode, ColorScheme, COLOR_CODES
 
 
 # Each type alias have their legal values described in comments - validation might be implemented in the future
@@ -19,12 +19,8 @@
 ConnectorMultiplier = PlainText # = Literal['pincount', 'populated']
 CableMultiplier = PlainText # = Literal['wirecount', 'terminations', 'length', 'total_length']
 ImageScale = PlainText # = Literal['false', 'true', 'width', 'height', 'both']
-Color = PlainText # Two-letter color name = Literal[wv_colors._color_hex.keys()]
-ColorMode = PlainText # = Literal['full', 'FULL', 'hex', 'HEX', 'short', 'SHORT', 'ger', 'GER']
-ColorScheme = PlainText # Color scheme name = Literal[wv_colors.COLOR_CODES.keys()]
 
 # Type combinations
-Colors = PlainText # One or more two-letter color names (Color) concatenated into one string
 Pin = Union[int, PlainText] # Pin identifier
 PinIndex = int # Zero-based pin index
 Wire = Union[int, PlainText] # Wire number or Literal['s'] for shield
@@ -284,9 +280,9 @@ def __post_init__(self) -> None:
             if self.colors:  # use custom color palette (partly or looped if needed)
                 pass
             elif self.color_code:  # use standard color palette (partly or looped if needed)
-                if self.color_code not in wv_colors.COLOR_CODES:
+                if self.color_code not in COLOR_CODES:
                     raise Exception('Unknown color code')
-                self.colors = wv_colors.COLOR_CODES[self.color_code]
+                self.colors = COLOR_CODES[self.color_code]
             else:  # no colors defined, add dummy colors
                 self.colors = [''] * self.wirecount
 

src/wireviz/wv_colors.py

@@ -3,8 +3,6 @@
 
 from typing import Dict, List
 
-from wireviz.DataClasses import Color, Colors
-
 COLOR_CODES = {
     'DIN': ['WH', 'BN', 'GN', 'YE', 'GY', 'PK', 'BU', 'RD', 'BK', 'VT', 'GYPK', 'RDBU', 'WHGN', 'BNGN', 'WHYE', 'YEBN',
             'WHGY', 'GYBN', 'WHPK', 'PKBN', 'WHBU', 'BNBU', 'WHRD', 'BNRD', 'WHBK', 'BNBK', 'GYGN', 'YEGY', 'PKGN',
@@ -112,7 +110,14 @@
 _hex_digits = set('0123456789abcdefABCDEF')
 
 
-def get_color_hex(input, pad=False):
+# Literal type aliases below are commented to avoid requiring python 3.8
+Color = str  # Two-letter color name = Literal[_color_hex.keys()]
+Colors = str  # One or more two-letter color names (Color) concatenated into one string
+ColorMode = str  # = Literal['full', 'FULL', 'hex', 'HEX', 'short', 'SHORT', 'ger', 'GER']
+ColorScheme = str  # Color scheme name = Literal[COLOR_CODES.keys()]
+
+
+def get_color_hex(input: Colors, pad: bool = False) -> List[str]:
     """Return list of hex colors from either a string of color names or :-separated hex colors."""
     if input is None or input == '':
         return [color_default]
@@ -156,7 +161,7 @@ def from_hex(hex_input: str) -> str:
            [translate.get(input[i:i+2], '??') for i in range(0, len(input), 2)]
 
 
-def translate_color(input, color_mode):
+def translate_color(input: Colors, color_mode: ColorMode) -> str:
     if input == '' or input is None:
         return ''
     upper = color_mode.isupper()