From cb40c32ac6af748d5afa79838a6807dd0a8d6bb0 Mon Sep 17 00:00:00 2001
From: Chiawen Chen <golopot@gmail.com>
Date: Sun, 8 Mar 2020 18:39:06 +0800
Subject: [PATCH] [Fix] `no-unused-state`: handle optional chaining

Fixes #2515
---
 lib/rules/no-unused-state.js       |  2 +-
 tests/lib/rules/no-unused-state.js | 22 ++++++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/lib/rules/no-unused-state.js b/lib/rules/no-unused-state.js
index 05bc08b29a..e05ef73cd4 100644
--- a/lib/rules/no-unused-state.js
+++ b/lib/rules/no-unused-state.js
@@ -415,7 +415,7 @@ module.exports = {
         handleAssignment(node.id, node.init);
       },
 
-      MemberExpression(node) {
+      'MemberExpression, OptionalMemberExpression'(node) {
         if (!classInfo) {
           return;
         }
diff --git a/tests/lib/rules/no-unused-state.js b/tests/lib/rules/no-unused-state.js
index f6ded949bd..2ad25901a3 100644
--- a/tests/lib/rules/no-unused-state.js
+++ b/tests/lib/rules/no-unused-state.js
@@ -231,6 +231,28 @@ eslintTester.run('no-unused-state', rule, {
           }
         }`,
       parser: parsers.BABEL_ESLINT
+    }, {
+      code: `
+        class OptionalChaining extends React.Component {
+          constructor() {
+            this.state = { foo: 0 };
+          }
+          render() {
+            return <SomeComponent foo={this.state?.foo} />;
+          }
+        }`,
+      parser: parsers['@TYPESCRIPT_ESLINT']
+    }, {
+      code: `
+        class OptionalChaining extends React.Component {
+          constructor() {
+            this.state = { foo: 0 };
+          }
+          render() {
+            return <SomeComponent foo={this.state?.foo} />;
+          }
+        }`,
+      parser: parsers.BABEL_ESLINT
     },
     `class VariableDeclarationTest extends React.Component {
         constructor() {