fix(eslint-plugin): [dot-notation] false positive with optional chain…

…ing (#3711) closes #3510
typescript-eslint · Aug 30, 2021 · c19fc6e · c19fc6e
1 parent 71dd273
commit c19fc6e
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Showing 2 changed files with 22 additions and 4 deletions.
diff --git a/packages/eslint-plugin/src/rules/dot-notation.ts b/packages/eslint-plugin/src/rules/dot-notation.ts
@@ -110,10 +110,9 @@ export default createRule<Options, MessageIds>({
             const objectType = typeChecker.getTypeAtLocation(
               esTreeNodeToTSNodeMap.get(node.object),
             );
-            const indexType = typeChecker.getIndexTypeOfType(
-              objectType,
-              ts.IndexKind.String,
-            );
+            const indexType = objectType
+              .getNonNullableType()
+              .getStringIndexType();
             if (indexType != undefined) {
               return;
             }

diff --git a/packages/eslint-plugin/tests/rules/dot-notation.test.ts b/packages/eslint-plugin/tests/rules/dot-notation.test.ts
@@ -99,6 +99,25 @@ x['hello'] = 3;
       `,
       options: [{ allowIndexSignaturePropertyAccess: true }],
     },
+    {
+      code: `
+interface Nested {
+  property: string;
+  [key: string]: number | string;
+}
+
+class Dingus {
+  nested: Nested;
+}
+
+let dingus: Dingus | undefined;
+
+dingus?.nested.property;
+dingus?.nested['hello'];
+      `,
+      options: [{ allowIndexSignaturePropertyAccess: true }],
+      parserOptions: { ecmaVersion: 2020 },
+    },
   ],
   invalid: [
     {