From daaa2063bb8755249d61bd3f5617336983bf4193 Mon Sep 17 00:00:00 2001
From: Jayen Ashar <jayenashar@users.noreply.github.com>
Date: Thu, 2 Jan 2020 01:36:20 +1100
Subject: [PATCH] Override toString in case this function is printed (#10949)

* Override toString in case this function is printed

Related to https://stackoverflow.com/questions/59543968/unexpected-return-value-from-visitor-method

* Don't override `toString` if `wrapper` is true

Override `toString` immediately before returning a newFn, otherwise it will be overridden if wrapper is true

https://github.com/babel/babel/pull/10949#discussion_r362302625

* prettier
---
 packages/babel-traverse/src/visitors.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/packages/babel-traverse/src/visitors.js b/packages/babel-traverse/src/visitors.js
index 77c1488d5d55..eb8516a451fa 100644
--- a/packages/babel-traverse/src/visitors.js
+++ b/packages/babel-traverse/src/visitors.js
@@ -227,6 +227,11 @@ function wrapWithStateOrWrapper(oldVisitor, state, wrapper: ?Function) {
         newFn = wrapper(state.key, key, newFn);
       }
 
+      // Override toString in case this function is printed, we want to print the wrapped function, same as we do in `wrapCheck`
+      if (newFn !== fn) {
+        newFn.toString = () => fn.toString();
+      }
+
       return newFn;
     });