fn test_simple_write_bits()

in src/cpuid/src/bit_helper.rs [422:555]

• 130 lines of code
• 1 McCabe index (conditional complexity)

    fn test_simple_write_bits() {
        let mut val: u32 = 0;

        // Test a couple of successive ranges
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 3,
                    lsb_index: 2
                },
                0b00
            ) == &0b0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 4,
                    lsb_index: 2
                },
                0b100
            ) == &0b10000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 5,
                    lsb_index: 2
                },
                0b0100
            ) == &0b01_0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 6,
                    lsb_index: 2
                },
                0b0_0100
            ) == &0b001_0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 7,
                    lsb_index: 2
                },
                0b00_0100
            ) == &0b0001_0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 8,
                    lsb_index: 2
                },
                0b100_0100
            ) == &0b1_0001_0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 9,
                    lsb_index: 2
                },
                0b0100_0100
            ) == &0b01_0001_0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 10,
                    lsb_index: 2
                },
                0b1_0100_0100
            ) == &0b101_0001_0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 11,
                    lsb_index: 2
                },
                0b01_0100_0100
            ) == &0b0101_0001_0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 12,
                    lsb_index: 2
                },
                0b101_0100_0100
            ) == &0b1_0101_0001_0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 13,
                    lsb_index: 2
                },
                0b1101_0100_0100
            ) == &0b11_0101_0001_0000
        );

        // Test max left and max right
        val = 0;
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 31,
                    lsb_index: 15
                },
                0b1_0000_0000_0000_0000
            ) == &0b1000_0000_0000_0000_0000_0000_0000_0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 14,
                    lsb_index: 0
                },
                0b011_0101_0001_0000
            ) == &0b1000_0000_0000_0000_0011_0101_0001_0000
        );
        assert!(
            val.write_bits_in_range(
                &BitRange {
                    msb_index: 31,
                    lsb_index: 0
                },
                0b1000_0000_0000_0000_0011_0101_0001_0000
            ) == &0b1000_0000_0000_0000_0011_0101_0001_0000
        );
    }