Merge #370

370: Self params & type r=matklad a=flodiebold

This implements type inference for `self`, so field completion for methods taking `self` works now.

 - rename `IMPL_ITEM` to `IMPL_BLOCK` -- rustc calls the methods etc. inside an impl `ImplItem`s, and the impl itself doesn't define an item, so I thought this name was clearer.
 - add HIR for impl blocks -- we collect all impls in a crate at once, so we can go from methods to containing impls, and since we will later also need to find all impls for a certain type (which may be anywhere in the crate, I think?). We could be more lazy here, but I don't know if it's worth the complexity.
 - resolve `self` and `Self` during type inference
 - refactor a bit in ty.rs as well

Co-authored-by: Florian Diebold <[email protected]>

1 files changed, 13 insertions, 1 deletions

diff --git a/crates/ra_hir/src/ids.rs b/crates/ra_hir/src/ids.rs
index 66adacc7d..4d6378e02 100644
--- a/crates/ra_hir/src/ids.rs
+++ b/crates/ra_hir/src/ids.rs
@@ -2,7 +2,7 @@ use ra_db::{SourceRootId, LocationIntener, Cancelable, FileId};
 use ra_syntax::{SourceFileNode, SyntaxKind, SyntaxNode, SyntaxNodeRef, SourceFile, AstNode, ast};
 use ra_arena::{Arena, RawId, impl_arena_id};
 
-use crate::{HirDatabase, PerNs, ModuleId, Module, Def, Function, Struct, Enum};
+use crate::{HirDatabase, PerNs, ModuleId, Module, Def, Function, Struct, Enum, ImplBlock, Crate};
 
 /// hir makes a heavy use of ids: integer (u32) handlers to various things. You
 /// can think of id as a pointer (but without a lifetime) or a file descriptor
@@ -177,6 +177,18 @@ impl DefId {
         let loc = self.loc(db);
         Module::new(db, loc.source_root_id, loc.module_id)
     }
+
+    /// Returns the containing crate.
+    pub fn krate(&self, db: &impl HirDatabase) -> Cancelable<Option<Crate>> {
+        Ok(self.module(db)?.krate(db))
+    }
+
+    /// Returns the containing impl block, if this is an impl item.
+    pub fn impl_block(self, db: &impl HirDatabase) -> Cancelable<Option<ImplBlock>> {
+        let loc = self.loc(db);
+        let module_impls = db.impls_in_module(loc.source_root_id, loc.module_id)?;
+        Ok(ImplBlock::containing(module_impls, self))
+    }
 }
 
 impl DefLoc {