fix: arrow-body-style crash with single-token body (#19379)

mdjermanovic · web-flow · commit 8bcd820f37f2 · 2025-01-28T12:22:33.000-05:00
diff --git a/lib/rules/arrow-body-style.js b/lib/rules/arrow-body-style.js
@@ -143,7 +143,7 @@ module.exports = {
 
                     if (blockBody.length === 0) {
                         messageId = "unexpectedEmptyBlock";
-                    } else if (blockBody.length > 1) {
+                    } else if (blockBody.length > 1 || blockBody[0].type !== "ReturnStatement") {
                         messageId = "unexpectedOtherBlock";
                     } else if (blockBody[0].argument === null) {
                         messageId = "unexpectedSingleBlock";
diff --git a/tests/lib/rules/arrow-body-style.js b/tests/lib/rules/arrow-body-style.js
@@ -534,6 +534,14 @@ ruleTester.run("arrow-body-style", rule, {
                 { line: 1, column: 27, type: "ArrowFunctionExpression", messageId: "unexpectedOtherBlock" }
             ]
         },
+        {
+            code: "var foo = () => { bar };",
+            output: null, // not fixed
+            options: ["never"],
+            errors: [
+                { line: 1, column: 17, type: "ArrowFunctionExpression", messageId: "unexpectedOtherBlock" }
+            ]
+        },
         {
             code: "var foo = () => { return 0; };",
             output: "var foo = () => 0;",
