Added type hints to ImageColor

src/PIL/ImageColor.py

@@ -25,7 +25,7 @@
 
 
 @lru_cache
-def getrgb(color):
+def getrgb(color: str) -> tuple[int, int, int] | tuple[int, int, int, int]:
     """
      Convert a color string to an RGB or RGBA tuple. If the string cannot be
      parsed, this function raises a :py:exc:`ValueError` exception.
@@ -44,8 +44,10 @@ def getrgb(color):
     if rgb:
         if isinstance(rgb, tuple):
             return rgb
-        colormap[color] = rgb = getrgb(rgb)
-        return rgb
+        rgb_tuple = getrgb(rgb)
+        assert len(rgb_tuple) == 3
+        colormap[color] = rgb_tuple
+        return rgb_tuple
 
     # check for known string formats
     if re.match("#[a-f0-9]{3}$", color):
@@ -88,15 +90,15 @@ def getrgb(color):
     if m:
         from colorsys import hls_to_rgb
 
-        rgb = hls_to_rgb(
+        rgb_floats = hls_to_rgb(
             float(m.group(1)) / 360.0,
             float(m.group(3)) / 100.0,
             float(m.group(2)) / 100.0,
         )
         return (
-            int(rgb[0] * 255 + 0.5),
-            int(rgb[1] * 255 + 0.5),
-            int(rgb[2] * 255 + 0.5),
+            int(rgb_floats[0] * 255 + 0.5),
+            int(rgb_floats[1] * 255 + 0.5),
+            int(rgb_floats[2] * 255 + 0.5),
         )
 
     m = re.match(
@@ -105,15 +107,15 @@ def getrgb(color):
     if m:
         from colorsys import hsv_to_rgb
 
-        rgb = hsv_to_rgb(
+        rgb_floats = hsv_to_rgb(
             float(m.group(1)) / 360.0,
             float(m.group(2)) / 100.0,
             float(m.group(3)) / 100.0,
         )
         return (
-            int(rgb[0] * 255 + 0.5),
-            int(rgb[1] * 255 + 0.5),
-            int(rgb[2] * 255 + 0.5),
+            int(rgb_floats[0] * 255 + 0.5),
+            int(rgb_floats[1] * 255 + 0.5),
+            int(rgb_floats[2] * 255 + 0.5),
         )
 
     m = re.match(r"rgba\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$", color)
@@ -124,7 +126,7 @@ def getrgb(color):
 
 
 @lru_cache
-def getcolor(color, mode: str) -> tuple[int, ...]:
+def getcolor(color: str, mode: str) -> int | tuple[int, ...]:
     """
     Same as :py:func:`~PIL.ImageColor.getrgb` for most modes. However, if
     ``mode`` is HSV, converts the RGB value to a HSV value, or if ``mode`` is
@@ -136,33 +138,34 @@ def getcolor(color, mode: str) -> tuple[int, ...]:
 
     :param color: A color string
     :param mode: Convert result to this mode
-    :return: ``(graylevel[, alpha]) or (red, green, blue[, alpha])``
+    :return: ``graylevel, (graylevel, alpha) or (red, green, blue[, alpha])``
     """
     # same as getrgb, but converts the result to the given mode
-    color, alpha = getrgb(color), 255
-    if len(color) == 4:
-        color, alpha = color[:3], color[3]
+    rgb, alpha = getrgb(color), 255
+    if len(rgb) == 4:
+        alpha = rgb[3]
+        rgb = rgb[:3]
 
     if mode == "HSV":
         from colorsys import rgb_to_hsv
 
-        r, g, b = color
+        r, g, b = rgb
         h, s, v = rgb_to_hsv(r / 255, g / 255, b / 255)
         return int(h * 255), int(s * 255), int(v * 255)
     elif Image.getmodebase(mode) == "L":
-        r, g, b = color
+        r, g, b = rgb
         # ITU-R Recommendation 601-2 for nonlinear RGB
         # scaled to 24 bits to match the convert's implementation.
-        color = (r * 19595 + g * 38470 + b * 7471 + 0x8000) >> 16
+        graylevel = (r * 19595 + g * 38470 + b * 7471 + 0x8000) >> 16
         if mode[-1] == "A":
-            return color, alpha
-    else:
-        if mode[-1] == "A":
-            return color + (alpha,)
-    return color
+            return graylevel, alpha
+        return graylevel
+    elif mode[-1] == "A":
+        return rgb + (alpha,)
+    return rgb
 
 
-colormap = {
+colormap: dict[str, str | tuple[int, int, int]] = {
     # X11 colour table from https://drafts.csswg.org/css-color-4/, with
     # gray/grey spelling issues fixed.  This is a superset of HTML 4.0
     # colour names used in CSS 1.