From 4a05fa2bd677ecdaf1fe836fefcd11e66adab16f Mon Sep 17 00:00:00 2001
From: Ben Scott <ben@reload.me.uk>
Date: Mon, 2 Sep 2019 19:24:01 -0700
Subject: [PATCH] [fix] `display-name`: Fix false positives

Wrapping a named function declaration with a React.memo or
React.forwardRef will no longer throw an false positive error

Fixes #2324. Fixes #2269.
---
 lib/rules/display-name.js       |  29 ++++++++-
 tests/lib/rules/display-name.js | 104 ++++++++++++++++++++++++++++++++
 2 files changed, 131 insertions(+), 2 deletions(-)

diff --git a/lib/rules/display-name.js b/lib/rules/display-name.js
index ecfeaa7b4f..3c5c847110 100644
--- a/lib/rules/display-name.js
+++ b/lib/rules/display-name.js
@@ -90,13 +90,13 @@ module.exports = {
       const namedClass = (
         (node.type === 'ClassDeclaration' || node.type === 'ClassExpression') &&
         node.id &&
-        node.id.name
+        !!node.id.name
       );
 
       const namedFunctionDeclaration = (
         (node.type === 'FunctionDeclaration' || node.type === 'FunctionExpression') &&
         node.id &&
-        node.id.name
+        !!node.id.name
       );
 
       const namedFunctionExpression = (
@@ -202,6 +202,31 @@ module.exports = {
         markDisplayNameAsDeclared(node);
       },
 
+      CallExpression(node) {
+        if (!utils.isPragmaComponentWrapper(node)) {
+          return;
+        }
+
+        if (node.arguments.length > 0 && astUtil.isFunctionLikeExpression(node.arguments[0])) {
+          // Skip over React.forwardRef declarations that are embeded within
+          // a React.memo i.e. React.memo(React.forwardRef(/* ... */))
+          // This means that we raise a single error for the call to React.memo
+          // instead of one for React.memo and one for React.forwardRef
+          const isWrappedInAnotherPragma = utils.getPragmaComponentWrapper(node);
+
+          if (
+            !isWrappedInAnotherPragma &&
+            (ignoreTranspilerName || !hasTranspilerName(node.arguments[0]))
+          ) {
+            return;
+          }
+
+          if (components.get(node)) {
+            markDisplayNameAsDeclared(node);
+          }
+        }
+      },
+
       'Program:exit': function () {
         const list = components.list();
         // Report missing display name for all components
diff --git a/tests/lib/rules/display-name.js b/tests/lib/rules/display-name.js
index 0064bc4bc0..9f01354be5 100644
--- a/tests/lib/rules/display-name.js
+++ b/tests/lib/rules/display-name.js
@@ -455,6 +455,22 @@ ruleTester.run('display-name', rule, {
 
       export default React.memo(Component)
     `
+  }, {
+    code: `
+      import React from 'react'
+
+      const ComponentWithMemo = React.memo(function Component({ world }) {
+        return <div>Hello {world}</div>
+      })
+    `
+  }, {
+    code: `
+      import React from 'react'
+
+      const ForwardRefComponentLike = React.forwardRef(function ComponentLike({ world }, ref) {
+        return <div ref={ref}>Hello {world}</div>
+      })
+    `
   }, {
     code: `
       function F() {
@@ -684,6 +700,94 @@ ruleTester.run('display-name', rule, {
     errors: [{
       message: 'Component definition is missing display name'
     }]
+  }, {
+    code: `
+      import React from 'react'
+
+      const ComponentWithMemo = React.memo(({ world }) => {
+        return <div>Hello {world}</div>
+      })
+    `,
+    errors: [{
+      message: 'Component definition is missing display name'
+    }]
+  }, {
+    code: `
+      import React from 'react'
+
+      const ComponentWithMemo = React.memo(function() {
+        return <div>Hello {world}</div>
+      })
+    `,
+    errors: [{
+      message: 'Component definition is missing display name'
+    }]
+  }, {
+    code: `
+      import React from 'react'
+
+      const ForwardRefComponentLike = React.forwardRef(({ world }, ref) => {
+        return <div ref={ref}>Hello {world}</div>
+      })
+    `,
+    errors: [{
+      message: 'Component definition is missing display name'
+    }]
+  }, {
+    code: `
+      import React from 'react'
+
+      const ForwardRefComponentLike = React.forwardRef(function({ world }, ref) {
+        return <div ref={ref}>Hello {world}</div>
+      })
+    `,
+    errors: [{
+      message: 'Component definition is missing display name'
+    }]
+  }, {
+    // Only trigger an error for the outer React.memo
+    code: `
+      import React from 'react'
+
+      const MemoizedForwardRefComponentLike = React.memo(
+        React.forwardRef(({ world }, ref) => {
+          return <div ref={ref}>Hello {world}</div>
+        })
+      )
+    `,
+    errors: [{
+      message: 'Component definition is missing display name'
+    }]
+  }, {
+    // Only trigger an error for the outer React.memo
+    code: `
+      import React from 'react'
+
+      const MemoizedForwardRefComponentLike = React.memo(
+        React.forwardRef(function({ world }, ref) {
+          return <div ref={ref}>Hello {world}</div>
+       })
+      )
+    `,
+    errors: [{
+      message: 'Component definition is missing display name'
+    }]
+  }, {
+    // React does not handle the result of forwardRef being passed into memo
+    // ComponentWithMemoAndForwardRef gets shown as Memo(Anonymous)
+    // See https://github.com/facebook/react/issues/16722
+    code: `
+      import React from 'react'
+
+      const MemoizedForwardRefComponentLike = React.memo(
+        React.forwardRef(function ComponentLike({ world }, ref) {
+          return <div ref={ref}>Hello {world}</div>
+        })
+      )
+    `,
+    errors: [{
+      message: 'Component definition is missing display name'
+    }]
   }, {
     code: `
       import React from "react";