Split needless_borrow into two lints

[Jarcho]

Splits off the case where the borrow is used as a generic argument to a function. I think the two cases are different enough to warrant a separate lint.

The tests for the new lint have been reordered to group related parts together. Two warning have been dropped, one looked like it was testing the generic argument form, but it ends up triggering the auto-deref variant. The second was just a redundant test that didn't do anything interesting.

An issue with cycle detection is also included. The old version was checking if a cycle was reachable from a block when it should have been checking if the block is part or a cycle.

As a side note, I'm liking the style of just jamming all the tests into separate scopes in main.

changelog: Split off needless_borrows_for_generic_args from needless_borrow

[rustbot]

r? @llogiq

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[llogiq]

The code looks good, but I wonder if we shouldn't name the new lint needless_generic_arg_borrow (without the s) to be more alike the needless_borrow lint. Alternative (but longer) would be needless_borrow_by_generic_arg.

[Jarcho]

needless_borrow really should plural according to the lint naming guidelines. needless_borrows_for_generic_args would work.

[llogiq]

Thank you!

@bors r+

[bors]

📌 Commit 79247d9 has been approved by llogiq

It is now in the queue for this repository.

[bors]

⌛ Testing commit 79247d9 with merge 251a475...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: llogiq
Pushing 251a475 to master...