From b0533fe33cbbd2c07f11bf3a1e97494a73698016 Mon Sep 17 00:00:00 2001
From: Fred Vollmer <fredric.vollmer@gmail.com>
Date: Tue, 30 Jun 2020 07:14:00 -0400
Subject: [PATCH] fix(eslint-plugin-react-hooks): Support optional chaining
 when accessing prototype method inside useCallback and useMemo #19061
 (#19062)

* fix(eslint-plugin-react-hooks): Support optional chaining when accessing prototype method #19061

* run prettier

* Add fix for #19043
---
 .../ESLintRuleExhaustiveDeps-test.js          | 47 +++++++++++++++++++
 .../src/ExhaustiveDeps.js                     |  7 ++-
 2 files changed, 52 insertions(+), 2 deletions(-)

diff --git a/packages/eslint-plugin-react-hooks/__tests__/ESLintRuleExhaustiveDeps-test.js b/packages/eslint-plugin-react-hooks/__tests__/ESLintRuleExhaustiveDeps-test.js
index 9322952fa4..68a3bd6b77 100644
--- a/packages/eslint-plugin-react-hooks/__tests__/ESLintRuleExhaustiveDeps-test.js
+++ b/packages/eslint-plugin-react-hooks/__tests__/ESLintRuleExhaustiveDeps-test.js
@@ -289,6 +289,24 @@ const tests = {
         }
       `,
     },
+    {
+      code: normalizeIndent`
+        function MyComponent(props) {
+          useMemo(() => {
+            console.log(props.foo?.toString());
+          }, [props.foo]);
+        }
+      `,
+    },
+    {
+      code: normalizeIndent`
+        function MyComponent(props) {
+          useCallback(() => {
+            console.log(props.foo?.toString());
+          }, [props.foo]);
+        }
+      `,
+    },
     {
       code: normalizeIndent`
         function MyComponent() {
@@ -1235,6 +1253,35 @@ const tests = {
     },
   ],
   invalid: [
+    {
+      code: normalizeIndent`
+        function MyComponent(props) {
+          useCallback(() => {
+            console.log(props.foo?.toString());
+          }, []);
+        }
+      `,
+      errors: [
+        {
+          message:
+            "React Hook useCallback has a missing dependency: 'props.foo?.toString'. " +
+            'Either include it or remove the dependency array.',
+          suggestions: [
+            {
+              desc:
+                'Update the dependencies array to be: [props.foo?.toString]',
+              output: normalizeIndent`
+                function MyComponent(props) {
+                  useCallback(() => {
+                    console.log(props.foo?.toString());
+                  }, [props.foo?.toString]);
+                }
+              `,
+            },
+          ],
+        },
+      ],
+    },
     {
       code: normalizeIndent`
         function MyComponent() {
diff --git a/packages/eslint-plugin-react-hooks/src/ExhaustiveDeps.js b/packages/eslint-plugin-react-hooks/src/ExhaustiveDeps.js
index 33ff43a663..8a23c88cec 100644
--- a/packages/eslint-plugin-react-hooks/src/ExhaustiveDeps.js
+++ b/packages/eslint-plugin-react-hooks/src/ExhaustiveDeps.js
@@ -1287,10 +1287,13 @@ function collectRecommendations({
   function scanTreeRecursively(node, missingPaths, satisfyingPaths, keyToPath) {
     node.children.forEach((child, key) => {
       const path = keyToPath(key);
+      // For analyzing dependencies, we want the "normalized" path, without any optional chaining ("?.") operator
+      // foo?.bar -> foo.bar
+      const normalizedPath = path.replace(/\?$/, '');
       if (child.isSatisfiedRecursively) {
         if (child.hasRequiredNodesBelow) {
           // Remember this dep actually satisfied something.
-          satisfyingPaths.add(path);
+          satisfyingPaths.add(normalizedPath);
         }
         // It doesn't matter if there's something deeper.
         // It would be transitively satisfied since we assume immutability.
@@ -1299,7 +1302,7 @@ function collectRecommendations({
       }
       if (child.isRequired) {
         // Remember that no declared deps satisfied this node.
-        missingPaths.add(path);
+        missingPaths.add(normalizedPath);
         // If we got here, nothing in its subtree was satisfied.
         // No need to search further.
         return;