Crate weird_data

Generate random data in such a way as to make rare edge-cases very likely.

Disclaimer: the random number generators used in this crate are NOT CRYPTOGRAPHICALLY SECURE. Only use these generators for generating testing inputs, do not rely on them for cryptographic purposes in production code! For instance, you may test a cryptographic tool with these generators, but you may not deploy code that relies on these generators for security in production.

For instance, if generating a random f32 by uniformly sampling 32 bits of data, certain values will rarely appear, such as NAN and INFINITY. When doing randomized testing, like fuzzing, it isn’t very useful to repeatedly generate well-behaved data. It is much more useful if we can artificially increase the likelihood of these special values, so that we test with them more often.

Additionally, some random number crates will never generate certain problematic bit-patterns, such as NAN.

This crate is based on the fastrand crate.

This crate can work with no_std, if you disable the std feature. You cannot use the global functions when in a no_std environment. In that case, you can explicitly instantiate Wdg and call the methods on it. They are equivalent.

If using std, it’s more ergonomic to use the global functions in the [global_functions] module.

Structs

Wdg

A weird data generator

Functions

f32

Generate a random f32, such that special or problematic values are much more common than normal.

f64

Generate a random f64, such that special or problematic values are much more common than normal.

get_seed

Gives back the current seed that is being held by the thread-local generator.

i8

Generate a random i8 , such that special or problematic values are much more common than normal.

i16

Generate a random i16 , such that special or problematic values are much more common than normal.

i32

Generate a random i32 , such that special or problematic values are much more common than normal.

i64

Generate a random i64 , such that special or problematic values are much more common than normal.

i128

Generate a random i128 , such that special or problematic values are much more common than normal.

isize

Generate a random isize , such that special or problematic values are much more common than normal.

nan_f32

There are multiple bit patterns that are equivalent to a NAN. This generator covers all possible NAN values as specified in IEEE-754, even ones that Rust would normally not generate.

nan_f64

Generates a random f64 NAN value.

normal_f32

Generate a random f32 normal value

normal_f64

Generate a random f64 normal value

seed

Initialize the thread-local generator with the given seed.

special_f32

Generate a random f32 “special” value

special_f64

Generate a random f64 “special” value

special_i8

Generate a random i8 “special” value

special_i16

Generate a random i16 “special” value

special_i32

Generate a random i32 “special” value

special_i64

Generate a random i64 “special” value

special_i128

Generate a random i128 “special” value

special_isize

Generate a random isize “special” value

special_u8

Generate a random u8 “special” value

special_u16

Generate a random u16 “special” value

special_u32

Generate a random u32 “special” value

special_u64

Generate a random u64 “special” value

special_u128

Generate a random u128 “special” value

special_usize

Generate a random usize “special” value

subnormal_f32

Generates a random f32 denormal value.

subnormal_f64

Generates a random f64 denormal value.

u8

Generate a random u8 , such that special or problematic values are much more common than normal.

u16

Generate a random u16 , such that special or problematic values are much more common than normal.

u32

Generate a random u32 , such that special or problematic values are much more common than normal.

u64

Generate a random u64 , such that special or problematic values are much more common than normal.

u128

Generate a random u128 , such that special or problematic values are much more common than normal.

usize

Generate a random usize , such that special or problematic values are much more common than normal.