Error extensions cause stack overflow

[neslinesli93]

Expected Behavior

When using error extensions, I should be able to implement the ErrorExtensions trait for my errors and then call error.extend() inside resolvers. When querying a field that returns an error, I should be able to see the error along with the code and other custom fields I may add

Actual Behavior

The program crashes when calling the graphql endpoint. Here is the stacktrace

thread 'actix-rt|system:0|arbiter:0' has overflowed its stack
fatal runtime error: stack overflow

Steps to Reproduce the Problem

1. Run the error-extensions example contained in the examples folder
2. Call the extend query on the schema
3. The server crashes

Basically the code goes in a loop on this line, and then ultimately crashes

Specifications

• Version: Reproduced with the branches actix-web-v4-beta and master
• Platform:
• Subsystem:

[sunli829]

Fixed in v3.0.7 😁