[botbuilder-lg] [bug] Infinite Loop in Imports

[juharris]

Versions

What package version of the SDK are you using. botbuilder-lg: 4.9.2
What nodejs version are you using v10.18.1
What browser version are you using
What os are you using WSL

Describe the bug

Having two language generation files that import each other causes an infinite loop/exception.
It's not really the loop that concerns me, I assume this means that LG is reloading templates if I import a file twice throughout my structure so I'm concerned about the impact to loading time.

To Reproduce

In this example, I get an exception but I can't even see the whole trace because it's so long. With my templates that I actually use where the circular imports might not be so direct, parseFile just hangs.
a.lg:

> Import b.lg
[b](./b.lg)
# a
- a

b.lg:

> Import a.lg
[a](./a.lg)
# b
- b

code.ts:

import { Templates } from 'botbuilder-lg'
Templates.parseFile('a.lg')

Expected behavior

Should not cause an infinite loop/exception.

[bug]

[joshgummersall]

@luhan2017 @chon219 is this still an issue? If so please prioritize and categorize with labels. Thanks!

[chon219]

@luhan2017 @chon219 is this still an issue? If so please prioritize and categorize with labels. Thanks!

@boydc2014 @Danieladu could you please help verify it?

[Danieladu]

yes. We have discussed this issue in another thread. Personal think it can be marked as backlog.