A starter `lib.rs` for rust libraries that enables lots of clippy lints and provides some macros to make simple unit tests faster to write.

lib.rs

#![warn(
    clippy::all,
    clippy::pedantic,
    // clippy::cargo,
    // TODO: uncomment above

    // Restriction lints
    clippy::as_conversions,
    clippy::dbg_macro,
    clippy::decimal_literal_representation,
    clippy::else_if_without_else,
    clippy::exit,
    clippy::expect_used,
    clippy::filetype_is_file,
    clippy::float_cmp_const,
    clippy::get_unwrap,
    clippy::lossy_float_literal,
    clippy::mem_forget,
    clippy::multiple_inherent_impl,
    clippy::rest_pat_in_fully_bound_structs,
    clippy::unneeded_field_pattern,
    clippy::unreachable,
    clippy::unwrap_in_result,
    clippy::use_debug,
    clippy::verbose_file_reads,
    clippy::wrong_pub_self_convention,

    // TODO: uncomment below
    /*
    // These lints are useful to enable in your final code, but can be annoyingly noisy during
    // development. Just make sure to turn them on when you're done!
    clippy::missing_docs_in_private_items,
    clippy::panic_in_result_fn,
    clippy::todo,
    clippy::unimplemented,
    */
)]
// Tagging everything with #[must_use] can be a little annoying
#![allow(clippy::must_use_candidate)]
// Behavior that triggers this lint can actually be useful to enable better forward compatibility
#![allow(clippy::match_wildcard_for_single_variants)]

/* Example:
_test_eq {
    addition: (1 + 1, 2),
    trimming: ("hello, world".trim_start_matches("hello,"), " world"),
}
*/
#[macro_use]
macro_rules! _test_eq {
    ($($name:ident: $value:expr,)*) => {
        $(
            #[test]
            fn $name() {
                let (input, expected) = $value;
                assert_eq!(input, expected);
            }
        )*
    }
}

/* Example:
let x: Option<&str> = None;

_test_err {
    just_an_error: (Err("a basic error")),
    option_none_ok_or: (x.ok_or(0))
}
*/
#[macro_use]
macro_rules! _test_err {
    ($($name:ident: $value:expr,)*) => {
        $(
            #[test]
            fn $name() {
                assert!($value.is_err());
            }
        )*
    }
}

// This contains all possible derives included in the standard library
// #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
// This is a basic starter that will work for the vast majority of cases
// #[derive(Clone, Debug)]

/*** Submodules ***/
// mod foo;
// pub mod bar;

/*** Re-imports ***/
// use foo::Foo;
// pub use bar::Bar;

/*** Top-level implementations ***/
// use std::fs::File
// type Baz = File;