Merge #1928

1928: Support `#[cfg(..)]` r=matklad a=oxalica

This PR implement `#[cfg(..)]` conditional compilation. It read default cfg options from `rustc --print cfg` with also hard-coded `test` and `debug_assertion` enabled.
Front-end settings are **not** included in this PR.

There is also a known issue that inner control attributes are totally ignored. I think it is **not** a part of `cfg` and create a separated issue for it. #1949

Fixes #1920 

Related: #1073 


Co-authored-by: uHOOCCOOHu <[email protected]>
Co-authored-by: oxalica <[email protected]>

1 files changed, 1 insertions, 0 deletions

diff --git a/crates/ra_hir/src/lib.rs b/crates/ra_hir/src/lib.rs
index 00031deba..4340e9d34 100644
--- a/crates/ra_hir/src/lib.rs
+++ b/crates/ra_hir/src/lib.rs
@@ -44,6 +44,7 @@ mod traits;
 mod type_alias;
 mod type_ref;
 mod ty;
+mod attr;
 mod impl_block;
 mod expr;
 mod lang_item;