From c4dd9d0f4bd0794a182bbced61a03a5ec4345ada Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Nowak?= <pawel.nowak@netguru.co>
Date: Wed, 8 May 2019 21:29:41 +0200
Subject: [PATCH] Verify function expression

---
 .../no-unused-class-component-methods.js      |  7 ++++-
 .../no-unused-class-component-methods.js      | 31 +++++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/lib/rules/no-unused-class-component-methods.js b/lib/rules/no-unused-class-component-methods.js
index 3f3919fc6b..ab75920f60 100644
--- a/lib/rules/no-unused-class-component-methods.js
+++ b/lib/rules/no-unused-class-component-methods.js
@@ -58,7 +58,12 @@ module.exports = {
         node.type === 'ClassProperty' &&
         node.value.type === 'ArrowFunctionExpression'
       );
-      return isMethod || isArrowFunction;
+      const isFunctionExpression = (
+        node.type === 'ClassProperty' &&
+        node.value.type === 'FunctionExpression'
+      );
+
+      return isMethod || isArrowFunction || isFunctionExpression;
     };
     const checkMethods = node => {
       const properties = astUtil.getComponentProperties(node);
diff --git a/tests/lib/rules/no-unused-class-component-methods.js b/tests/lib/rules/no-unused-class-component-methods.js
index 9bee715f75..cb2c278b5a 100644
--- a/tests/lib/rules/no-unused-class-component-methods.js
+++ b/tests/lib/rules/no-unused-class-component-methods.js
@@ -228,6 +228,19 @@ ruleTester.run('no-unused-class-component-methods', rule, {
         }
       `,
       parser: 'babel-eslint'
+    },
+    {
+      code: `
+        class Foo extends React.Component {
+          action = function() {
+            console.log('error');
+          }
+          render() {
+            return <button onClick={() => this.action()}>Click</button>;
+          }
+        }
+      `,
+      parser: 'babel-eslint'
     }
   ],
 
@@ -352,6 +365,24 @@ ruleTester.run('no-unused-class-component-methods', rule, {
         line: 3,
         column: 11
       }]
+    },
+    {
+      code: `
+        class Foo extends React.Component {
+          action = function() {
+            console.log('error');
+          }
+          render() {
+            return null;
+          }
+        }
+      `,
+      parser: 'babel-eslint',
+      errors: [{
+        message: 'Unused method "action" of class "Foo"',
+        line: 3,
+        column: 11
+      }]
     }
   ]
 });