Catch typos like 1_32 instead of 1_i32

[scottmcm]

I missed a letter in a very subtle way that still compiled, so it might be a good candidate for linting:

let mut x = 1_32;

when I meant to type

let mut x = 1_i32;

This, of course, made it do something very different from what I wanted...

[mipli]

Just had an issue with this myself, so I wouldn't mind solving this one.

Been looking a bit into it, and thinking that it would fit to add it as another lint in the clippy_lints/src/literal_representation.rs file.

What I'm wondering though is what the name of the new lint should be. misstyped_literal, misstyped_literal_suffix?

And I'm assuming it should go into the correctness group, due to the label on this issue.

[flip1995]

Been looking a bit into it, and thinking that it would fit to add it as another lint in the clippy_lints/src/literal_representation.rs file.

Yes sounds good!

I think misstyped_literal_suffix is a good name for this.

correctness feels like the right lint group for this.

[oli-obk]

Naming conventions say it should be mistyped_literal_suffixes so allow(mistyped_literal_suffixes) sounds like an english sentence

[dtolnay]

Added in #3129.