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, 31 insertions, 0 deletions

diff --git a/crates/ra_syntax/src/ast.rs b/crates/ra_syntax/src/ast.rs
index 7f986d322..2a3bd27e2 100644
--- a/crates/ra_syntax/src/ast.rs
+++ b/crates/ra_syntax/src/ast.rs
@@ -482,6 +482,37 @@ impl<'a> PrefixExpr<'a> {
     }
 }
 
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum SelfParamFlavor {
+    /// self
+    Owned,
+    /// &self
+    Ref,
+    /// &mut self
+    MutRef,
+}
+
+impl<'a> SelfParam<'a> {
+    pub fn flavor(&self) -> SelfParamFlavor {
+        let borrowed = self.syntax().children().any(|n| n.kind() == AMP);
+        if borrowed {
+            // check for a `mut` coming after the & -- `mut &self` != `&mut self`
+            if self
+                .syntax()
+                .children()
+                .skip_while(|n| n.kind() != AMP)
+                .any(|n| n.kind() == MUT_KW)
+            {
+                SelfParamFlavor::MutRef
+            } else {
+                SelfParamFlavor::Ref
+            }
+        } else {
+            SelfParamFlavor::Owned
+        }
+    }
+}
+
 #[test]
 fn test_doc_comment_of_items() {
     let file = SourceFileNode::parse(