test(rosetta): Extend submodule import test case for nested structs in submodules

[ansgarm]

Hi! I created this (failing) test case for a jsii-rosetta problem we are seeing in cdktf convert (bullet point # 2 in this comment).

Originally we uncovered that this code was invalid for Python but upon writing this test case, I think it is also producing invalid code for C# and Go. I'm not entirely sure whether I've adjusted the expected results in the right way, though. I'll add comments to those places including what Rosetta currently returns to make it easier to see how these tests currently fail.

I'd be open to contribute to a solution but I'm having a hard time even describing the problem in the right terms 😅

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[ansgarm]

This currently fails as the result from Rosetta is missing the Submodule.Child. for AnotherStruct

[ansgarm]

While looking at this once more, I noticed that the original test already seems to have a small error, too:

Suggested change

	var myClass = new Submodule.MyClass(new SomeStruct { Prop = Submodule.Child.SomeEnum.SOME, NestedStruct = new Submodule.Child.AnotherStruct { StringProperty = "hello" } });
	var myClass = new Submodule.MyClass(new Submodule.Child.SomeStruct { Prop = Submodule.Child.SomeEnum.SOME, NestedStruct = new Submodule.Child.AnotherStruct { StringProperty = "hello" } });

[ansgarm]

This currently fails as the result from Rosetta is returning anotherStruct instead of AnotherStruct

[ansgarm]

This currently fails as the result from Rosetta is missing the calc.submodule.child. for AnotherStruct

[ansgarm]

@DanielMSchmidt just pointed me at https://github.com/aws/jsii-compiler which is where JSII 5.0 lives – I'll create a new PR over there as we're on JSII 5.0 now 😄

Edit: I'll create it in https://github.com/aws/jsii-rosetta of course 😄

[ansgarm]

Hm, I could use some help there – it seems like jsii-calc still needs to be updated in this repo, right?
In that case, I won't create that other PR just yet, as it won't really work (= fail successfully) anyway yet 😅

[RomainMuller]

@ansgarm the jsii compiler 5.0.x lives in aws/jsii-compiler, and the jsii-rosetta 5.0.x lives in aws/jsii-rosetta.

The jsii-calc package (and dependencies) are "copied" in aws/jsii-compiler (under the fixtures directory), and have been slightly edited there to improve the v5.0 coverage... Unfortunately, since they need to assess some backwards-compatibility behavior, the code there had to be updated to include TypeScript 3.9-incompatible syntax... So it's not just a matter of copying the code over.

If jsii-calc here is lacking some APIs you need for your tests, you could just add the necessary changes into this PR...