ace} -0.7 -0.5 -0.3 / 0)`);
        test_valid_value(`color`, `color(from color(${colorSpace} -0.7 -0.5 -0.3 / -40%) ${colorSpace} r g b / alpha)`,            `color(${colorSpace} -0.7 -0.5 -0.3 / 0)`);

        // Testing with calc().
        test_valid_value(`color`, `color(from color(${colorSpace} 0.7 0.5 0.3) ${colorSpace} calc(r) calc(g) calc(b))`,                        `color(${colorSpace} 0.7 0.5 0.3)`);
        test_valid_value(`color`, `color(from color(${colorSpace} 0.7 0.5 0.3 / 40%) ${colorSpac