Auto merge of #12054 - y21:issue12037, r=Jarcho

add external macro checks to `iter_without_into_iter` and `into_iter_without_iter`

Fixes #12037

I think it's useful to still lint on local macros, since the user should still be able to add another impl with the `IntoIterator` or `iter` method. I think it's also fairly common to write a macro for generating many impls (e.g. for many similar types), so it'd be nice if we can continue linting in those cases.
For that reason I went with `in_external_macro`.

I also added a test for `#[allow]`ing the lint while I was at it.

changelog: [`iter_without_into_iter`]: don't lint if the `iter` method is defined in an external macro
changelog: [`into_iter_without_iter`]: don't lint if the `IntoIterator` impl is defined in an external macro

0 files changed, 0 insertions, 0 deletions