`await circuitReady` freezes execution in `quantum-register.js`

[louislefevre]

Bug Description

When executing a quantum register for the first time in a fresh Node-RED session, the await circuitReady code will freeze execution. If the circuit is re-run a second time during the same session, it will run just fine. Essentially, this bug only occurs when the circuit is being run for the first time in a given session. After that, it runs fine.

Steps to Reproduce Bug

• Start a fresh Node-RED session.
• Run the following simple circuit (as an example).
• Execution will stop at await circuitReady in quantum-register.js.
• Run the circuit again.
• The flow will execute again, but this time it won't get stuck at await circuitReady.

Additional Information

https://github.com/louislefevre/node-red-contrib-quantum/blob/46a8320cb304cc4b58438429b398bc780ad7d832/quantum/nodes/quantum-register/quantum-register.js#L105

System Information

• Node.js Version: 16.6.2
• Operating System: Arch Linux (5.13.10)

[bbaayezi]

The bug was caused by emitting the circuitReady event before the quantum register nodes advanced to await circuitReady() line. A slight change in execution order and use process.nextTick() to emit event solves the issue.