`integer_arithmetic` triggers in derive macro code

[michaelsproul]

Summary

The integer_arithmetic lint triggers in code generated by derive macros.

It seems this is a slightly broader issue affecting multiple lints, e.g. #9657, #7845.

If the right solution is to check any_parent_is_automatically_derived or in_external_macro I would be happy to do the implementation for integer_arithmetic.

Reproducer

I tried this code with arbitrary@1.2.2:

#![deny(clippy::integer_arithmetic)]

use arbitrary::Arbitrary;

#[derive(Arbitrary)]
pub struct Thing {
    pub x: u64,
}

The error is:

error: integer arithmetic detected
 --> src/lib.rs:5:10
  |
5 | #[derive(Arbitrary)]
  |          ^^^^^^^^^
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#integer_arithmetic
note: the lint level is defined here
 --> src/lib.rs:1:9
  |
1 | #![deny(clippy::integer_arithmetic)]
  |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
  = note: this error originates in the derive macro `Arbitrary` (in Nightly builds, run with -Z macro-backtrace for more info)

Version

rustc 1.66.0 (69f9c33d7 2022-12-12)
binary: rustc
commit-hash: 69f9c33d71c871fc16ac445211281c6e7a340943
commit-date: 2022-12-12
host: x86_64-unknown-linux-gnu
release: 1.66.0
LLVM version: 15.0.2

Additional Labels

No response

[Jarcho]

This needs is_from_proc_macro. any_parent_is_automatically_derived would work if the proc macro adds the #[automatically_derived] attribute, but quite a few of them don't. The other issues have the same fix.