Lifetimes UI test cleanup
* Removes an unneeded `#![warn(clippy::extra_unused_lifetimes)]` from
the `needless_lifetimes` test - the tests for those are in a different
file.
* Renames `unused_lt.{rs,stderr}` to `extra_unused_lifetimes.{rs,stderr}`
* Renames `lifetimes.{rs,stderr}` to `needless_lifetimes.{rs,stderr}`
* Removes an unneeded `#![warn(clippy::extra_unused_lifetimes)]` from
the `needless_lifetimes` test - the tests for those are in a different
file.
* Renames `unused_lt.{rs,stderr}` to `extra_unused_lifetimes.{rs,stderr}`
* Renames `lifetimes.{rs,stderr}` to `needless_lifetimes.{rs,stderr}`
Added lint for TryFrom for checked integer conversion.
works towards #3947
Added lint for try_from for checked integer conversion.
Should recognize simple & straight-forward checked integer conversions.
Fix compile-test from forcing a rebuild.
If the `compile-test` test was run, then running a cargo build command immediately after caused everything to be rebuilt. This is because the `compile-test` test was deleting all `.rmeta` files in the target directory. Cargo recently switched to always generating `.rmeta` files (https://github.com/rust-lang/cargo/pull/6883), and when the files are deleted, it thinks it needs to be rebuilt.
I am not very familiar with compiletest or clippy, so please take a close look and test this out (with the most recent nightly). In particular, make sure it doesn't revert the fixes from #3380 (it seems to work for me). Also @oli-obk mentioned something related in https://github.com/rust-lang/rust/pull/60190#issuecomment-493617188, and I want to make sure that is addressed as well.
Fixes#4114
Merge backport branches into master
Attempt 2 at https://github.com/rust-lang/rust-clippy/pull/4103
This does nothing to the code, however it keeps the backport branches in master history, so that deleting a branch won't accidentally break old rustc builds
Add a stderr file length check to clippy_dev
This adds a check to `clippy_dev` that enforces a maximum line count for
`stderr` files. CI will fail if the line count is exceeded. It's
currently set to `320` lines.
Ideally this would be implemented in `compiletest-rs` but there are
plans to move Rust's `compiletest` into the `compiletest-rs` repository
and I don't want to do the work in `compiletest` twice. However, I also
don't want to wait until the move is done, so I added the check to
`clippy_dev` until it makes sense to add it to compiletest-rs.
cc #2038
