Macro strict_encoding::test_encoding_enum_u8_exhaustive

macro_rules! test_encoding_enum_u8_exhaustive {
    ($enum : path ; $($item : path => $val : expr), +) => { ... };
    ($enum : path as $ty : ty ; $($item : path => $val : expr), +) => { ... };
    ($se : ident => $enum : path ; $($item : path => $val : expr), +) => { ... };
    ($se : ident => $enum : path as $ty : ty ; $($item : path => $val : expr), +) => { ... };
}

Macro testing encoding of all possible enum values, covering full range of u8 values, including enum out-of-range values.

Macro expands into an expression of Result<(), EnumEncodingTestFailure> type.

Macro extends functionality of test_encoding_enum_by_values and should be used whenever enum with assigned primitive values is represented by u8 integers.

Covered test cases

• Each enum variant must have a primitive value
• Primitive value representing enum variant must be equal to strict encoding of the same variant. If a primitive enum value occupies of several bytes (u16, u32 and other large integer types), strict encoding must match little-endian encoding of the value
• Roundtrip encoding-decoding of the enum variant must result in the original value
• Each enum variant must be equal to itself
• Each enum variant must not be equal to any other enum variant
• Enum variants must be ordered according to their primitive values
• All 8-bit integers which do not match any of enum variants must not be decoded with strict decoder into a valid enum and their decoding must result in Error::EnumValueNotKnown error.

Example

#[derive(Copy, Clone, Ord, PartialOrd, Eq, PartialEq, Debug)]
#[repr(u8)]
#[derive(StrictEncode, StrictDecode)]
#[strict_encoding(repr = u8, by_value)]
enum Bits {
    Bit8 = 8,
    Bit16 = 16,
}

test_encoding_enum_u8_exhaustive!(
    Bits as u8;
    Bits::Bit8 => 8_u8, Bits::Bit16 => 16_u8
).unwrap();