Implement tuple inference

2 files changed, 20 insertions, 1 deletions

diff --git a/crates/ra_hir/src/expr.rs b/crates/ra_hir/src/expr.rs
index 593fe1598..f0936e9f3 100644
--- a/crates/ra_hir/src/expr.rs
+++ b/crates/ra_hir/src/expr.rs
@@ -183,6 +183,9 @@ pub enum Expr {
         arg_types: Vec<Option<TypeRef>>,
         body: ExprId,
     },
+    Tuple {
+        exprs: Vec<ExprId>,
+    },
 }
 
 pub use ra_syntax::ast::PrefixOp as UnaryOp;
@@ -297,6 +300,11 @@ impl Expr {
             | Expr::UnaryOp { expr, .. } => {
                 f(*expr);
             }
+            Expr::Tuple { exprs } => {
+                for expr in exprs {
+                    f(*expr);
+                }
+            }
         }
     }
 }
@@ -621,11 +629,14 @@ impl ExprCollector {
                 let op = e.op();
                 self.alloc_expr(Expr::BinaryOp { lhs, rhs, op }, syntax_ptr)
             }
+            ast::ExprKind::TupleExpr(e) => {
+                let exprs = e.exprs().map(|expr| self.collect_expr(expr)).collect();
+                self.alloc_expr(Expr::Tuple { exprs }, syntax_ptr)
+            }
 
             // TODO implement HIR for these:
             ast::ExprKind::Label(_e) => self.alloc_expr(Expr::Missing, syntax_ptr),
             ast::ExprKind::IndexExpr(_e) => self.alloc_expr(Expr::Missing, syntax_ptr),
-            ast::ExprKind::TupleExpr(_e) => self.alloc_expr(Expr::Missing, syntax_ptr),
             ast::ExprKind::ArrayExpr(_e) => self.alloc_expr(Expr::Missing, syntax_ptr),
             ast::ExprKind::RangeExpr(_e) => self.alloc_expr(Expr::Missing, syntax_ptr),
             ast::ExprKind::Literal(_e) => self.alloc_expr(Expr::Missing, syntax_ptr),
diff --git a/crates/ra_hir/src/ty.rs b/crates/ra_hir/src/ty.rs
index 5d5568d69..0692d3b2a 100644
--- a/crates/ra_hir/src/ty.rs
+++ b/crates/ra_hir/src/ty.rs
@@ -1040,6 +1040,14 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
                 }
                 _ => Ty::Unknown,
             },
+            Expr::Tuple { exprs } => {
+                let mut ty_vec = Vec::with_capacity(exprs.len());
+                for arg in exprs.iter() {
+                    ty_vec.push(self.infer_expr(*arg, &Expectation::none())?);
+                }
+
+                Ty::Tuple(Arc::from(ty_vec))
+            }
         };
         // use a new type variable if we got Ty::Unknown here
         let ty = self.insert_type_vars_shallow(ty);