Touch up type inference for boolean operators

Also try to infer its subexpressions and set type expectations
whenever possible.

3 files changed, 26 insertions, 26 deletions

diff --git a/crates/ra_syntax/src/ast.rs b/crates/ra_syntax/src/ast.rs
index 1bce6fa40..9df8ec663 100644
--- a/crates/ra_syntax/src/ast.rs
+++ b/crates/ra_syntax/src/ast.rs
@@ -511,20 +511,33 @@ impl<'a> BinExpr<'a> {
     pub fn op(&self) -> Option<BinOp> {
         self.syntax()
             .children()
-            .filter_map(|c| {
-                match c.kind() {
-                    PIPEPIPE => Some(BinOp::BooleanOr),
-                    AMPAMP => Some(BinOp::BooleanAnd),
-                    EQEQ => Some(BinOp::EqualityTest),
-                    LTEQ => Some(BinOp::LesserEqualTest),
-                    GTEQ => Some(BinOp::GreaterEqualTest),
-                    L_ANGLE => Some(BinOp::LesserTest),
-                    R_ANGLE => Some(BinOp::GreaterTest),
-                    _ => None,
-                }
+            .filter_map(|c| match c.kind() {
+                PIPEPIPE => Some(BinOp::BooleanOr),
+                AMPAMP => Some(BinOp::BooleanAnd),
+                EQEQ => Some(BinOp::EqualityTest),
+                LTEQ => Some(BinOp::LesserEqualTest),
+                GTEQ => Some(BinOp::GreaterEqualTest),
+                L_ANGLE => Some(BinOp::LesserTest),
+                R_ANGLE => Some(BinOp::GreaterTest),
+                _ => None,
             })
             .next()
     }
+
+    pub fn lhs(self) -> Option<Expr<'a>> {
+        children(self).nth(0)
+    }
+
+    pub fn rhs(self) -> Option<Expr<'a>> {
+        children(self).nth(1)
+    }
+
+    pub fn sub_exprs(self) -> (Option<Expr<'a>>, Option<Expr<'a>>) {
+        let mut children = children(self);
+        let first = children.next();
+        let second = children.next();
+        (first, second)
+    }
 }
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
diff --git a/crates/ra_syntax/src/ast/generated.rs b/crates/ra_syntax/src/ast/generated.rs
index ac320606d..7df6a9c46 100644
--- a/crates/ra_syntax/src/ast/generated.rs
+++ b/crates/ra_syntax/src/ast/generated.rs
@@ -217,15 +217,7 @@ impl<R: TreeRoot<RaTypes>> BinExprNode<R> {
 }
 
 
-impl<'a> BinExpr<'a> {
-    pub fn lhs(self) -> Option<Expr<'a>> {
-        super::child_opt(self)
-    }
-
-    pub fn rhs(self) -> Option<Expr<'a>> {
-        super::child_opt(self)
-    }
-}
+impl<'a> BinExpr<'a> {}
 
 // BindPat
 #[derive(Debug, Clone, Copy,)]
diff --git a/crates/ra_syntax/src/grammar.ron b/crates/ra_syntax/src/grammar.ron
index e59961da3..c55e9e07a 100644
--- a/crates/ra_syntax/src/grammar.ron
+++ b/crates/ra_syntax/src/grammar.ron
@@ -422,12 +422,7 @@ Grammar(
         "RefExpr": (options: ["Expr"]),
         "PrefixExpr": (options: ["Expr"]),
         "RangeExpr": (),
-        "BinExpr": (
-            options: [
-                ["lhs", "Expr"],
-                ["rhs", "Expr"]
-            ]
-        ),
+        "BinExpr": (),
         "String": (),
         "Byte": (),
         "ByteString": (),