This commit makes `cargo clippy` output the build artifacts to a
separate directory if the `CLIPPY_DOGFOOD` env var is set. This should
prevent dogfood builds from interfering with regular builds.
This should help with issue #2595.
From the clippy side it's difficult to detect empty lines between
an attributes and the following item because empty lines and comments
are not part of the AST. The parsing currently works for basic cases
but is not perfect and can cause false positives.
Maybe libsyntax 2.0 will fix some of the problems around attributes but
comments will probably be never part of the AST so we would still have
to do some manual parsing.
Before, when you had a block comment between an attribute and the
following item like this:
```rust
\#[crate_type = "lib"]
/*
*/
pub struct Rust;
```
It would cause a false positive on the lint, because there is an empty
line inside the block comment.
This makes sure that basic block comments are detected and removed from
the snippet that was created before.
Now that we're using cargo check, we can stop needing to find out the
manifest path ourselves. Instead, we can delegate to cargo check, which
is perfectly capable of working out for itself what needs to be built.
This fixes#1707 and #2518.
Note that this PR will change the output. We will no longer output `bin:
foo` before each crate. This a bit unfortunate. However, given that
we're now going to be building in parallel (which is *much* faster), I
think this is acceptable - we'll be no worse than cargo itself.
Closes#2397.
This checks the def of the `ItemUse` path instead of checking the
capitalization of the path segements. It was noted that this def would
sometimes be `Def::Mod` instead of `Def::Enum` but it seems correct now.
`empty_line_after_outer_attribute` produced a false positive warning when
deriving `Copy` and/or `Clone` for an item.
It looks like the second point in [this comment][that_comment] is related,
as the attribute that causes the false positive has a path of
`rustc_copy_clone_marker`.
Fixes#2475
[that_comment]: https://github.com/rust-lang/rust/issues/35900#issuecomment-245978831
