renew-fixed 0.1.1

Fixed-point arithmetic for simulation code that must reproduce bit-for-bit
Documentation 
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# Crate-local lint configuration (a crate-local file fully replaces the

# workspace one, so the test allowances are repeated).

#

# This crate is not simulation-designated — it holds no state to reproduce —

# but it is the arithmetic every simulation is written in, so the same

# tripwires apply for the same reason: a value this type produces reaches a

# state hash, and anything non-deterministic that leaked in here would

# reach one too, one call further along.

#

# The float deny is at the crate root rather than here, where it sits beside

# the sentence explaining it.



allow-unwrap-in-tests = true

allow-expect-in-tests = true

allow-panic-in-tests = true



disallowed-methods = [

    { path = "std::time::Instant::now", reason = "arithmetic reads no clock; a number type that consulted one would make every result a function of when it ran" },

    { path = "std::time::SystemTime::now", reason = "arithmetic reads no clock; a number type that consulted one would make every result a function of when it ran" },

    { path = "std::thread::spawn", reason = "this crate has nothing to parallelise and simulation is single-threaded regardless" },

    { path = "std::thread::Builder::spawn", reason = "the named-thread spelling of the same act" },

    { path = "std::fs::read", reason = "this crate never touches the filesystem" },

    { path = "std::fs::write", reason = "this crate never touches the filesystem" },

    { path = "std::fs::File::open", reason = "this crate never touches the filesystem" },

    { path = "std::fs::File::create", reason = "this crate never touches the filesystem" },

]



disallowed-types = [

    { path = "std::hash::RandomState", reason = "it seeds itself from the operating system, and nothing behind a reproducibility contract may" },

    { path = "std::collections::hash_map::DefaultHasher", reason = "same reason as RandomState: self-seeding entropy has no place here" },

    { path = "std::collections::HashMap", reason = "the default hasher is seeded per instance, so iteration order varies between runs of the same binary" },

    { path = "std::collections::HashSet", reason = "the default hasher is seeded per instance, so iteration order varies between runs of the same binary" },

]



# The SAFETY-comment lint accepts the comment above an attribute or

# on the statement that owns the block.

accept-comment-above-statement = true

accept-comment-above-attributes = true