    `color(${colorSpace} 0.7 0.5 0.3 / 0)`);
    }

    for (const colorSpace of [ "xyz", "xyz-d50", "xyz-d65" ]) {
        const resultColorSpace = colorSpace == "xyz" ? "xyz-d65" : colorSpace;

        // Testing no modifications.
        test_valid_value(`color`, `color(from color(${colorSpace} 7 -20.5 100) ${colorSpace} x y z)`,                              `color(${resultColorSpace} 7 -20.5 100)`);
        test_valid_value(`color`, `color(from color(${colorSpace} 7 -20.5 100) ${colorSpace} x y z / alph