Merge #327

327: Beginnings of type inference r=flodiebold a=flodiebold

I was a bit bored, so I thought I'd try to start implementing the type system and see how far I come :wink:  This is obviously still extremely WIP, only very basic stuff working, but I thought I'd post this now to get some feedback as to whether this approach makes sense at all.

There's no user-visible effect yet, but the type inference has tests similar to the ones for the parser. My next step will probably be to implement struct types, after which this could probably be used to complete fields.

I realize this may all get thrown away when/if the compiler query system gets usable, but I feel like there are lots of IDE features that could be implemented with somewhat working type inference in the meantime :smile: 

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

1 files changed, 16 insertions, 2 deletions

diff --git a/crates/ra_hir/src/function.rs b/crates/ra_hir/src/function.rs
index 2925beb16..d36477b48 100644
--- a/crates/ra_hir/src/function.rs
+++ b/crates/ra_hir/src/function.rs
@@ -5,12 +5,13 @@ use std::{
     sync::Arc,
 };
 
+use ra_db::Cancelable;
 use ra_syntax::{
     TextRange, TextUnit,
     ast::{self, AstNode, DocCommentsOwner, NameOwner},
 };
 
-use crate::{ DefId, HirDatabase };
+use crate::{ DefId, HirDatabase, ty::InferenceResult, Module };
 
 pub use self::scope::FnScopes;
 
@@ -18,7 +19,7 @@ pub use self::scope::FnScopes;
 pub struct FnId(pub(crate) DefId);
 
 pub struct Function {
-    fn_id: FnId,
+    pub(crate) fn_id: FnId,
 }
 
 impl Function {
@@ -27,6 +28,10 @@ impl Function {
         Function { fn_id }
     }
 
+    pub fn syntax(&self, db: &impl HirDatabase) -> ast::FnDefNode {
+        db.fn_syntax(self.fn_id)
+    }
+
     pub fn scopes(&self, db: &impl HirDatabase) -> Arc<FnScopes> {
         db.fn_scopes(self.fn_id)
     }
@@ -35,6 +40,15 @@ impl Function {
         let syntax = db.fn_syntax(self.fn_id);
         FnSignatureInfo::new(syntax.borrowed())
     }
+
+    pub fn infer(&self, db: &impl HirDatabase) -> Cancelable<Arc<InferenceResult>> {
+        db.infer(self.fn_id)
+    }
+
+    pub fn module(&self, db: &impl HirDatabase) -> Cancelable<Module> {
+        let loc = self.fn_id.0.loc(db);
+        Module::new(db, loc.source_root_id, loc.module_id)
+    }
 }
 
 #[derive(Debug, Clone)]