fix: Fix ast::IfExpr child accessors

Author: Veykril

crates/syntax/src/ast/expr_ext.rs

@@ -49,22 +49,24 @@ impl From<ast::IfExpr> for ElseBranch {
 
 impl ast::IfExpr {
     pub fn then_branch(&self) -> Option<ast::BlockExpr> {
-        self.children_after_condition().next()
+        let mut exprs = support::children(self.syntax());
+        let first = exprs.next();
+        let second = exprs.next();
+        second.or(first)
     }
 
     pub fn else_branch(&self) -> Option<ElseBranch> {
-        let res = match self.children_after_condition().nth(1) {
-            Some(block) => ElseBranch::Block(block),
-            None => {
-                let elif = self.children_after_condition().next()?;
-                ElseBranch::IfExpr(elif)
-            }
-        };
-        Some(res)
+        let mut exprs = support::children(self.syntax()).nth(2)?;
+
+        match support::children(self.syntax()).nth(2)? {
+            ast::Expr::BlockExpr(block) => Some(ElseBranch::Block(block)),
+            ast::Expr::IfExpr(elif) => Some(ElseBranch::IfExpr(elif)),
+            _ => None,
+        }
     }
 
     fn children_after_condition<N: AstNode>(&self) -> impl Iterator<Item = N> {
-        self.syntax().children().skip(1).filter_map(N::cast)
+        self.syntax().children().filter_map(N::cast).skip(1)
     }
 }
 

crates/syntax/src/ast/node_ext.rs

@@ -939,7 +939,14 @@ impl From<ast::Adt> for ast::Item {
 
 impl ast::IfExpr {
     pub fn condition(&self) -> Option<ast::Expr> {
-        support::child(&self.syntax)
+        // If the condition is a BlockExpr, check if the then body is missing.
+        // If it is assume the condition is the expression that is missing instead.
+        let mut exprs = support::children(self.syntax());
+        let first = exprs.next();
+        match first {
+            Some(ast::Expr::BlockExpr(_)) => exprs.next().and(first),
+            first => first,
+        }
     }
 }