addressing pr comments

Author: ymc9

packages/language/src/validators/expression-validator.ts

@@ -108,20 +108,21 @@ export default class ExpressionValidator implements AstValidator<Expression> {
                     supportedShapes = ['Boolean', 'Any'];
                 }
 
+                const leftResolvedDecl = expr.left.$resolvedType?.decl;
+                const rightResolvedDecl = expr.right.$resolvedType?.decl;
+
                 if (
-                    expr.left.$resolvedType &&
-                    (typeof expr.left.$resolvedType?.decl !== 'string' ||
-                        !supportedShapes.includes(expr.left.$resolvedType.decl))
+                    leftResolvedDecl &&
+                    (typeof leftResolvedDecl !== 'string' || !supportedShapes.includes(leftResolvedDecl))
                 ) {
                     accept('error', `invalid operand type for "${expr.operator}" operator`, {
                         node: expr.left,
                     });
                     return;
                 }
                 if (
-                    expr.right.$resolvedType &&
-                    (typeof expr.right.$resolvedType?.decl !== 'string' ||
-                        !supportedShapes.includes(expr.right.$resolvedType.decl))
+                    rightResolvedDecl &&
+                    (typeof rightResolvedDecl !== 'string' || !supportedShapes.includes(rightResolvedDecl))
                 ) {
                     accept('error', `invalid operand type for "${expr.operator}" operator`, {
                         node: expr.right,
@@ -130,14 +131,11 @@ export default class ExpressionValidator implements AstValidator<Expression> {
                 }
 
                 // DateTime comparison is only allowed between two DateTime values
-                if (expr.left.$resolvedType?.decl === 'DateTime' && expr.right.$resolvedType?.decl !== 'DateTime') {
+                if (leftResolvedDecl === 'DateTime' && rightResolvedDecl && rightResolvedDecl !== 'DateTime') {
                     accept('error', 'incompatible operand types', {
                         node: expr,
                     });
-                } else if (
-                    expr.right.$resolvedType?.decl === 'DateTime' &&
-                    expr.left.$resolvedType?.decl !== 'DateTime'
-                ) {
+                } else if (rightResolvedDecl === 'DateTime' && leftResolvedDecl && leftResolvedDecl !== 'DateTime') {
                     accept('error', 'incompatible operand types', {
                         node: expr,
                     });