fix(color): implement ManimColor.gradient via color_gradient

manim/utils/color/core.py

@@ -958,11 +958,28 @@ def is_sequence(
     def gradient(
         colors: list[ManimColor], length: int
     ) -> ManimColor | list[ManimColor]:
-        """This method is currently not implemented. Refer to :func:`color_gradient` for
-        a working implementation for now.
+        """Create a gradient of colors interpolated between the given colors.
+
+        Parameters
+        ----------
+        colors
+            Reference colors to interpolate between.
+        length
+            Number of colors in the output gradient.
+
+        Returns
+        -------
+        ManimColor or list[ManimColor]
+            A single color if ``length == 1``, otherwise a list of colors.
+
+        See Also
+        --------
+        :func:`color_gradient`
         """
-        # TODO: implement proper gradient, research good implementation for this or look at 3b1b implementation
-        raise NotImplementedError
+        gradient = color_gradient(colors, length)
+        if length == 1:
+            return gradient[0]
+        return gradient
 
     def __repr__(self) -> str:
         return f"{self.__class__.__name__}('{self.to_hex()}')"

tests/module/utils/test_color_helpers.py

@@ -236,6 +236,21 @@ def test_color_gradient_passes_through_each_of_four_reference_colors() -> None:
     assert gradient[3] == WHITE
 
 
+def test_manim_color_gradient_matches_color_gradient() -> None:
+    gradient = ManimColor.gradient([BLACK, WHITE], 5)
+    assert gradient == color_gradient([BLACK, WHITE], 5)
+
+
+def test_manim_color_gradient_length_one_returns_single_color() -> None:
+    color = ManimColor.gradient([RED], 1)
+    assert isinstance(color, ManimColor)
+    assert color == RED
+
+
+def test_manim_color_gradient_zero_length_returns_empty_list() -> None:
+    assert ManimColor.gradient([RED], 0) == []
+
+
 # ---------------------------------------------------------------------------
 # Random color machinery
 # ---------------------------------------------------------------------------