7 -20.5 100 / 40%) ${colorSpace} calc(x) calc(y) calc(z) / calc(alpha))`,    `color(${resultColorSpace} 7 -20.5 100 / 0.4)`);

        // Testing with 'none'.
        test_valid_value(`color`, `color(from color(${colorSpace} 7 -20.5 100) ${colorSpace} none none none)`,                     `color(${resultColorSpace} none none none)`);
        test_valid_value(`color`, `color(from color(${colorSpace} 7 -20.5 100) ${colorSpace} none none none / none)`,              `color(${resultColorSpace} none none none / n